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Weather, January 2, 1991 Data: University of Illinois at Urbana-Champaign Dept. of Atmospheric Sciences Simulation of wind flow over an airfoil at Mach 0.5 Data: Dr. Mark Christon, Lawrence Livermore Labs Slice from 3D seismic survey Data: Halliburton Geophysical5ervices, Inc. Spyglass Transfocm 2.0 MacUser Eddy Award Winner for Best Science/Engineering Product, 1991 For international information contact Spyglass, Inc., at the address above, or-Australia: MacScience03 499 2(JJ7; France: Alsyd (Macintosh only) 76418430; Germany: SW Design 02408 (JJ71, Vistec06112 2037;Japan: IMI 0333653641, Sumisho Electronics0332191956; Netherlands: IVS0226353703; UK: Adept 0462480055 10 1992, Spyglass, Inc. Trademarks: SPY8'ass, Spyglass, Inc.; PostScript, Adobe Systems, Inc.; UNIX, AT&T Information Systems; Macintosll, Apple Computer, Inc.; Motif, Open Software Foundation. For More Information Circle No_ 609 for UNIX/Motif Version For More Information Circle No_ 612 for Macintosh Version SPECIAL FEATURES 12 Editorial Notebook 14 NASA Patents 16 Aerospace/Defense Technology Transfer 148 Mission Accomplished TECHNICAL SECTION 26 Electronic Components and Circuits ~ 26 Coupled-Cavity Traveling-Wave Tube Has Phase-Adjusted Taper 30 CCD With Back-Side Illumination and Charge Steering 32 Almond-Shaped Test Body 32 Faraday Cage Protects Against Lightning 37 Generating Far-Infrared Radiation by Two-Wave Mixing 40 Electronic Systems -'W 40 Improved Zero-Crossing Detector 42 Open-Loop Acquisition of Frequency in BPSK 42 Aircraft Engine-Monitoring System and Display 44 Scanning System Acquires Data at Designated Coordinates 46 Atomic Clock Based on Linear Ion Trap 48 Open-Loop Acquisition of Suppressed Carrier Signals 50 Eliminating Bias in Acousto-Optical Spectrum Analysis 52 Projected-Fringe, Phase-Stepping Profilometer 54 Simplified Digital Spectrum Analyzer 55 Acquisition Performances of QPSK Carrier-Tracking Loops 56 Performance of Digital Data-Transition- Tracking Loop 56 Behavior of Costas Loop in Reception of Telemetry 57 Effect of Phase Unbalance in Product Modulator 58 Physical Sciences '61 g-~j 6 58 Multilayer Monochromator for Hard X Rays and y Rays 58 Charge-Carrier-Scattering Spectroscopy With BEEM September 1992 Volume 16 Number 9 NI\S/\ Tech Briefs Transferring Engineering Technology to Over 200,000 Qualified Readers Throughout Industry and Government 60 High-Temperature Tribometer and Data- Acquisition System 62 Measurement of Residual Stress in Ferromagnetic Materials 64 Four-Sector Cylindrical Radio-Frequency Ion Trap 65 Chamber for Microgravity Combustion Experiments 66 Measuring Spatially Varying Transmit- tance of a Filter 68 Classification of Land Cover From Airborne MSS Data 68 Adjusting Curvatures of Large Mirrors and Lenses 70 Towed Articulated Housing for Geo- physical Measurements 71 Chamber for Testing Infrared Imaging Detectors 71 Variable-Temperatu re Cryostat fo r Radiation-Damage Testing of Germanium Detectors 72 Measuring Orientation of the Earth With GPS 72 Microwave Remote Sensing of Meteorological Quantities 73 Polarimetric Radar Signatures of Frozen and Thawed Forests 74 Geodetic Precession VS. Frame Dragging 74 Study of Space-Based Optical Interferometer 76 Materials 76 Fabrication of Metal Chloride Cathodes by Sintering 77 Pd/Cr Strain Gauges for High Temperatures 77 Thermally Conductive Fluid Compatible With Hypergols 78 Biaxially Stretched Polycarbonate Film for Capacitors 80 Computer Programs -W) 80 Software for Processing Meteorological Qi!£i§$b Data ~ ~ 80 Reformatting Data From X-Ray Photoelectron Spectroscopy 81 Operating System for Numerically Controlled Milling Machine 82 Software Graphical User Interface for Analysis of Images 99 Mechanics 99 Tool Would Grip Round Electrical Connectors (Continued on page 8) NASA Tech Briefs, September 1992 Do you wish you could find a bac1..'Up system fust rransfer rates plus the abilily Lo locate and with enough capacity, speed, and sophistica- restore your files quickly - about 75 times tion to backup unattended? fuster than normal speed. Could you recreate a document from CONFIGURATION FlIXIBlUTY. scratch in the time it takes you to restore it? The state-of-the-art llquid crystal display FAST BAOWp, FAST RESTORE. gives you complete drive status information. Introducing the CY-8500, the 8mm tape Command under execution, transfer rate, drive that gives you up to TRUE "PWG.AND.PLAY" tape remaining, and ECC 25 GB on a smgle tape. COMPATIBIUTY WITH: are presented in a clear And with o'ansfer rates Alllant HP PC 386111 easy-to-read format By of up to 90 MB per min- :::a Micro ::: AS/4OO ~ :I~S offering such features as ute, backup takes less Apollo Mainframe UniI data compression - for Altl IBM RtSC/lOOO Pettee fi time, frees resources, and AlIT IBM RT Plexus ve times the storage makes frequent backup :':~t :~ S/38 =Id capacity per tape - and imple and convenient ~ ~=h =nt data encryption - giving And that's not all. DEC 31tIOI5OOO MlclniOlh Graptllcs you data access control- The CY-8500 offers fust g:~ ~~':' ~::'I :m the CY-8500 adapts to file search capability. So g:~~:~ r:"ments your company's growing you get the advantages g~~ ~~: ~:II :.s: needs. We'll adapt to of high capacity and GouldlEncore PS/2 ."dlllllte your site requirements tOO, with rack mounnng opoons and cable lengths of up to 80 feet. PROVEN lKHNOLOGY. Best of all, the CY-8500 offers peace of mind. 8mm helical scan technology, designed for data recording, gives you demonstrated performance and reliability. ot an adapta- tion of an audio recording format. The CY-8500 is part of a complete family of tape backup products that range in capacity from the 250 MB \4" cartridge streamer to the 3 TB cartridge handling system. All backed up by our in-house technical support group and 12-month warranty. For more informa- tion on how you can enjoy the best value in tape backup, call today at 804/873-9000. For More Information Circle No. 322 Rock Landing Corporate Center' 11846 Rock Landing, Newport ews, VA 23606 . 804/873-9000 . FAX 804/873-8836 Contents (continued) 99 Joystick With Cable Springs Offers Better Feel 100 Systematic Disturbance of Optimal Rotational Trajectory 101 Self-Aligning Cranked Latch 103 Modular Heat Exchanger With Integral Heat Pipe 104 Power-Tool Adapter for T-handle Screws 105 Natural-Flow Wing 108 Fixture for Testing Ball Bearings Under Radial Loads 109 Water-Cooled Total-Temperature Probe 110 Absorption of Crushing Energy in Square Composite Tubes 110 Schlieren Photographic Studies of Dynamic Stall 111 Developing a Navier-Stokes Algorithm for Supercomputers 114 Machinery O 114 Direct-Interface, Fusible Heat Sink 115 Robot Control Based on Spatial-Operator Algebra 116 Sorbent-Bed Crop-Drying System 117 Manual Override for Electromechanical Latch 118 Fabrication Technology !!!!I 118 Cheaper Custom Shielding Cups for Arc E! Welding 118 Compact Througb-the-Torch Vision System 120 Curing a Large CompOSite Cylinder Without an Autoclave 121 Long-Wearing Wire Guide for Welding Torch 121 Preformed Superconductive Devices 122 Floating Ring-Groove Lapper 123 Guide for Assembly of Electrical Connector 124 Electroforming Repair of Adjacent Unconnected Layers 125 Ambient-Temperature Sputtering of Composite Oxide Films 126 Templates Aid Removal of Defects From Castings 126 Coating of Molded Battery Substrates 127 Shrink-Fit Solderable Inserts Seal Hermetically 127 Spectrum-Imaging Detector Array With Integrated Filter 128 Precise Countersinking Tool 129 Mathematics and Information Sciences tj 129 Iterative Bayesian Classification in Polarimetric SAR 1 29 Synchronization of Parallel Discrete Event Simulations 134 Life Sciences ~ '13345 Shape-Memory Probe Grasps Small Objects Apparatus Induces and Fixes Small Aquatic Organisms 136 Gravity, Calcium, and Bone: Update, 1989 136 Effects of Exercise During Prolonged Bed Rest J\6P W BPA DEPARTMENTS New Product Ideas .............................. 20 NASA TU Services .............................. 24 New on the Market ............................ 138 New Literature ................................... 140 Subject Index ..................................... 142 Advertisers Index .............................. 147 on the cover: With the Cold War over and aerospace budgets shrinking rapidly, U.S. defense/aerospace contractors are moving into new commercial markets. The cover photo shows an aero- space-based technique for laser deposition of superconduct- ing thin films that its developer, TRW Inc., is transferring to such industries as medicine and computing. Turn to our special report on page 16. Photo courtesy TRW Space & T echnotogy Group This document was prepared under the sponsorship of the National Aeronautics and Space Administration. Neither Associated Business Publications Co., Ltd. nor anyone acting on behalf of Associated Business Publications Co., Ltd. nor the United States Government nor any person acting on behalf of the United States Government assumes any liability resulting from the use of the information contained in this document, or warrants that such use will be free from privately owned rights. The U.S. Government does not endorse any commercial product, process, or activity identified in this publication. PermiSSions: Authorization to photocopy ~ems for Intemal or personal use, or the Intemal or personal use of specific clients, is granted by Associated Business Publlcahons. prOVided that the the flat fee of $3.00 per copy is paid directly to the Copyright Clearance Center (21 Congress St., Salem, MA 01970). For those organizallons that have been granted a photocopy license by CCC, a separate sy£tem of payment has been arranged The fee code for users of the Transactional Repor1lng ServICe IS; ISSN 0145·319X192 $3.00+ .00 NASA Tech Briefs, ISSN 0145·319X, USPS 750·070, copynght C 1992 In U.S .. is published monthly by ASSOCiated BUSiness Publications Co., Ltd .. 41 E. 42nd SI, New York, NY 10017-5391 . The copynghted Informahon does not include the (U. S. nghts to) Individual tech bnefs which are supplied by NASA. Editorial, sales, production and circulation offices at 41 East 42nd Street. New York, NY 10017-5391 . Subscription for non-qualified subscribers In the U.S. , Panama Canal Zone, and Puerto RICO, $75.00 for 1 year: $125.00 for 2 years: $200.00 for 3 years. Single copies $1 0.00. Foreign subSCriptions one-year U.S. Funds $150.00. Remit by check, draft, postal, express orders or VISA, MasterCard, and American Express. Other reminances at sende~s risk. Address all communications for subscriptions or circulation to NASA Tech Briefs, 41 East 42nd Street, New York, NY 10017·5391 Second-class postage paid at New York, NY and additional mailing offices. POSTMASTER: please send address changes to NASA Tech Briefs, 41 E. 42nd Street, Suite 921 , New York, NY 10017-5391 . 8 NASA Tech Briefs, September 1992 SCIENCE/ SCOPE® Managing masses of information on globaL environmental change - a major goal of NASA' s Earth Observing System (EOS) - is one of the world's most formidable information management ystem cballenges. The Hughes Aircraft Company solution for the EOS Data and Information System (EOSDIS) will electronically interconnect NASA and other government agencies with researchers worldwide - facilitating research collaboration through a distributed federation of heterogeneous computer systems . Hi torically , global change data has been awkward to access, tough to translate and difficult to distribute. However, with EOSDIS, scientists in faraway places can easily work closely together, analyzing our fragile planet and recommending ways to preserve its environment and natural resources. Now in its third cycle of mapping the surface of Venus, the spacecraft Magellan is close to its goal of producing a complete map of the planet. The key to gathering data is the Hughes-built synthetic aperture radar, the sole scientific instrument aboard Magellan. Even before the first cycle ended, in mid-1991, Magellan had mapped 84% of Venus ' surface, returning more digital data than all previous U .S. planetary missions combined, with re olutions 10 times better than those provided by earlier missions. To optimize radar performance, Hughes also designed a computer software program capable of handling the nearly 950 commands required per cycle. Each cycle takes one Venusian "day," the equivalent of 243 Earth-days. In what is likely the most intricate satellite replacement scenario ever, Hughes will soon launch its first pair of dual-payload satellites, Galaxy IV and Galaxy VII. They will replace Hughes' existing Ku-band and C-band satellites at the orbital positions of 99 degrees and 91 degrees, respecti vel y. What makes this especially complicated is that they will be launched within four months of one another, requiring an unprecedented feat of choreography that includes backup satellites both in orbit and on the ground. This will enable Hughes to maintain ongoing, uninterrupted service to existing customers, who collectively have more than 25 ,000 satellite di hes - mostly in fixed positions - pointed at their existing fleet. GM' prototype electric car. called Impact, will have Hughes-built electronics powering the motor and controlling the recharging. This all solid-state ystem requireu no scheduled maintenance and will appear in the showrooms well ahead of the 1998 date when California will require auto manufacturers to begin selling zero pollution cars. Recharge points will be installed at buyers' homes and will also appear in other locations, including employee parking lots, downtown parking facilities , malls, and restaurant. With its Hughes-built "Inverter," the Impact will be a model for cars that help protect our environment. Hughes is now producing the world ' s first interactive entertainment simulator which offer the excitement of a true simulation environment through integrated real-time control of vi ion, motion, and CD quality sound. These simulators use many of the same technologies Hughes developed for sophisticated flight simulators used in training pilot of Boeing 747-400s and military aircraft. The Commander simulator capsules are hydraulically operated as you steer through the computer image-generated screen experience. Becau e the graphics are generated as the adventure is experienced, you can go wherever you want in the scenario. The Commander includes a variety of safety features and will be located at arcades, shopping malls , bowling alleys , leisure center • amusement/theme parks, as well as airports and museums. For more information write to: P.O. Box 80032, Los Angeles, CA 9OO8()'OO32 HUGHES Ii) 1992 Hughes Aircraft Company Subsidiary of GM Hughes Electronics 10 For More Information Circle No. 467 NJ\S/\ Tech Briefs Official Publication of National Aeronautics and Space Administration ARP WBPA NASA Tech Briefs: Published by ......... ............. . ........... Associated Business Publica tions Edrtor·in·ChieflPublisher ............................. Bill Schnirring ASSOCIate PublisherlEditor ................. Joseph T. Pram berger Managing Editor ...................... R,J. laer Associate Editor ........................... . ............ Sarah l . Gall Technical Advisor ................... . ... .......... Dr. Robert E. Waterman Production Manager ... . ................................... Rita Nothaft Traffic Manager .................. ........ ......................... James E, Cobb Art Director ........................... . ........................ ........... Pierre Granier Marketing Director .. . .................. ............... Wayne Pierce Advertising Coordinator ..... . .......... Nipa Joshi Telecommunications Specialist .... . ........ Evelyn Mars Reader Service Manager ...... .... ...... . ..... Scott Floman Briefs & Supporting literature: Provided to National Aeronautics and Space Administration by International Computers & Telecommunications, Inc., NY, NY with assistance from logical Technical Services, NY, NY Technical/Managing Editor ... . .. ..... ................ Ted Selinsky Art Director .............. ....... .. ........... . .. luis Martinez Administrator ........... . ............... Elizabeth Texeira Chief Copy Editor ... .................................................. .. ......... lorne Bullen Staff Writers/Editors ........ Dr. James Boyd, Dr. larry Grunberger, Dr. Theron Cole, Jordan Randjefovich, George Watson, Oden Browne Graphics .. . ....... ....... ... ..... ....... . Zinaida Glmpeleva, Vernald Gillman, Pamela Baynham, Charles Sammartano Editorial & Production .... . ................ Bill l ittle, Ivonne Valdes, Susan Kyu Oh, Frank Ponce NASA: NASA Tech Briefs are provided by the National Aeronautics and Space Administration, Technology Transfer Division, Washington , DC: Administrator ............................ ..... .. .... Daniel S. Goldin Assistant Administrator for Commercial Programs ........... John G. Mannix Deputy Assistant Administrator(Programs) ................ Frank E, Penaranda Deputy Director Technology Transfer Division (Publications Manager) . .... ................ .. .. ........ leonard A. Ault Manager, Technology Transfer Office, NASA Center For AeroSpace Information ........................................... Walter M. Heiland Associated Business Publications 41 East 42nd Street, Suite 921 , New York, NY 10017·5391 (212) 490·3999 FAX (212) 986·7864 President ..................................... .. .. ............ Bill Schnirrlng Executive Vice President .............. ..................... .. ...... Frank Nothaft Vice President/Chief Operating Officer .. Domenic A. Mucchettl Operations Manager .................... Rita Nothaft Controller . .. .. Feleeia lahey Trade Show Director ... .. .... ........... Wendy S. Janiel Systems Analyst ............................. .. .................. Patrick Wolfert Advertising: New York Ottiee : (212) 490-3999 FAX (212) 986·7864 Account Executives : NY, NJ, OH, MI NJ (Area Codes 201 and 908) PA, DE, NJ (Area Code 609) VA, DC, MD, WV ... Brian Clerkin at (201) 366·2751 ..................................... .. Debby Crane at (201) 967·9838 .. ....... Tara Morie at (215) 640·3118 ......... John D. Floyd, CBC at (215) 399·3265 Eastern MA, NH, ME, RI .... .. ......................... Paul Gillespie at (508) 429·8907; Bill Doucette at (508) 429·9861 Western MA, CT, VT ............................ .. .... George Watts West Central, Southeast, Southwest Midwest-IL, WI, MN ..... MN .................................. . Northwest-WA, OR ........ at (413) 253·9881 ........... Douglas Shaller at (212) 490·3999 .. .......... Paul lesher, cec at (31 2) 296·2040 .. .... David Haggett at (708) 934·9123 .. ......... Bill Hague at (206) 858·7575 West Coast-CA, AZ, NV, NM, UT .................................. Stillman Group at (310) 372·2744 for Area Codes 60217021505/818/805: Paul Sanacore for 310/619n14 : Robert D'Alexander __ ~ 408/41519161209n 07/801 : Tom Sti llman NTBM·Research Center Account Supervisor .............. .. .. . .. ..................... lourdes Del Valle NASA Tech Briefs, September 1992 Only Sony g'v •• you hAr'e ......... nchw ...... 'n h .. N ........ . For More Information Circle No. 632 ea L,I-L.cal:J~ PUMPHEADS QUICK, EASY & COST EFFICIENT Easy-Load~ pump heads are EASY! EASY to maintain ••• Change tubing for fast pump cleanup. Chemical resistant housings/rotors. EASY to change flow rates •.• Each pump head accepts several sizes of tubing. Flow ranges from 0.06 ml/min to 13 LPM. EASY to stack for multichannel pumping .•. Change tubing without dismantling pump. EASY on your budget •.. Affordably priced with a 2 year warranty. Enjoy the benefits of a high value, 10woCost Masterflex system! Get the complete story in the 12S·page Masterflex Reference Book. Send for your FREE copy today. c~~ C7Pormer FREE! Cole-Parmer® Instrument Co. 7425 N. Oak Park Avenue· Niles, IL 60714 DIAL: 1·800-323·4340 or 1·708·647·7600 FAX: 1·708·647·9660 For More Informatin Circle No. 416 Editorial Notebook National Technology Transfer Week Back in January when I reported to you the phenomenal success of the Technology 2001 conference, I promised that we would do our best to make Technology 2002 even better. As optimistic as I am bent to be, little did I know then that this December Technology 2002 would be the centerpiece of National Technology Transfer Week. We have been fortunate to have two of the most prestigious organizations in the country agree to dovetail their efforts with Technology 2002 to maximize the return on our nation's investment in R&D and help U.S. industry retain its global leadership . The President's National Technology Initiative (NTI), a federal initiative supported by the Secretaries of Commerce, Energy, Transportation, and NASA's Administrator, will lead off National Technology Transfer Week on December 1 with a conference designed to foster partnerships between the government and private sector that will yield new goods and services to boost the economy. The NTI will segue into Technology 2002, with its hundreds of exhibits and sympo- sia, and all the excitement generated by the 6000+ engi- neers and executives who will attend this premier technol - ogy transfer show. Technology 2002 will flow into the MIT Enterprise Forum's Entrepreneurial Technology Transfer Conference, to be held at the Baltimore Hyatt Hotel from December 4-6, which will focus on techniques and strategies for effective tech transfer. The NTI , Technology 2002, and the MIT Enterprise Forum will jointly sponsor a press conference and reception on Monday evening , November 30, and will officially kick off the week's activities with a plenary session the next morning. All three groups will participate in this year's technology transfer awards banquet on Wednesday, December 3, at which achievement awards will be presented to federal employees and contractors who have made major strides in turning taxpayer-supported research into new products and processes that benefit daily life. We are honored to have as our dinner speaker Norman Augustine , Chairman and CEO of Martin Marietta Corporation . The convergence of these activites signals the coming of age of technology transfer. Everyone who wants to be competitive in the high-tech arena in coming years should plan to attend National Technology Transfer Week in Balti- more, November 30-December 5. For further details about th is unique opportunity, turn to the section beginning on page 83 . Cl l NASA Tech Briefs, September 1992 Tranter, inc. and Dean Products, Inc. have supplied efficient and Rexible PlATECOIL~, PANELCOIL~ and CRYOPANEL~ prime surface heat exchangers for a wide variety of space age projects- from large and small solar simulator space chambers, to components for jet and rocket engine test stands, to heat exchange surfaces for helium cryopumping, to bell jar shrouds. With the acquisition of Dean Products' assets and the addition of a large, dedicated location for production of special space-oriented heat exchangers at its Wichita Falls, TX facility, Tranter is now producing PANELCOIL and CRYOPANEL products, in addition to PlATECOIL units. These outstanding heat exchangers can be supplied with grit blasted and blackened interior surfaces for low emissivity and high absorptivity to enhance acceptance of radiation from test objects. Outside surfaces can be electropolished for high emissivity and low absorptivity, reAecting radiation to reduce cryo-liquid usage. Discover the unparalleled versatility of PlATECOIL, PANELCOIL and CRYOPANEL units, and the potential efficiency and savings they can bring For More Information Circle No. 594 to your operation. Call us at (817) 723-7125, or contact your local Tranter representative. Better still, ask your local Tranter representative about our Heat Transfer Symposiums. The heat transfer answer. ranter TRANTER, inc., Texas Division Old Burk Road • P.O. Box 2289 Wichita Falls TX 76307 . (817) 723-7125 TELEX: 73-4410· FAX: (817) 723-5131 C 1992 TRANTER. inc. - MADE IN U.SA 6501112 ........ • Analog I/O • Digital I/O • Counter/Timers • Motor/Machine Control • RS232/422, IEEE 488 • Memory • Supporting Software Backed by CONTEC's 3-year warranty, 30-day evaluation and free technical support. CALL 800·888·8884, 8·5 Pacific Time Or Contact: Free Catalog CONTEC Microelectronics U.S.A. Inc. 2188 Bering Drive, San Jose, CA 95131 (408) 434-6767 FAX (408) 434-6884 ~TENTS Over the past three decades, NASA has granted more than 1000 patent licenses in virtually every area of technology. The agency has a portfolio of 3000 patents and pending applications available now for license by businesses and individuals, in· cluding these recently patented inventions: Method of Fabricating Composite Structures (US Patent No. 5,084,219) Inventor: Wanda A . Sigur, Marshall Space Flight Center Ms. Sigur offers a way to fabricate large, lightweight, and strong laminated structures without the use of costly autoclaves. The composite structure is positioned about a high-coefficient-of-thermal-expansion mate- rial and then wrapped in a graphite fiber. Heating the assembly causes the material to expand and forcibly compress the compos- ite structure against the graphite overwrap. For More Information Circle No. 696. Optical Joint Correlator for Real-Time Image Tracking and Retinal Surgery (US Patent No. 5,029,220) Inventor: Richard D. Juday, Johnson Space Center Mr. Juday has developed a method for track- ing an object in a sequence of images, such as a sequence of television frames. Using an optical joint correlator, the object's position in a frame is correlated with its position in the previous frame to determine its relative loca- tion. The correlator can be used in laser eye surgery to track the involuntary movement of the eyeball . With knowledge of the eyeball's position, a surgical laser can be precisely pointed toward a location on the retina. For More Information Circle No. 691 . Metallic Threaded Composite Fastener (US Patent No. 5,090,857) Inventor: ThomasJ. Dunn, Johnson Space Center Suited for high-temperature applications such as thermal protection systems, Mr. Dunn's fastener has a body made of temperature- resistant composite material with a ceramic coating, a non-circular shank, and an exter- nally threaded split collar of metal alloy se- cured to the shank by a lock ring. When torque is transmitted from the body to the collar, the tapered connecting surface be- tween the collar and the shank allows the collar to apply a tensile load to the shank without damaging the ceramic coating. For More Information Circle No. 693. Rolling Friction Robot Fingers (US Patent No. 5, 120, 101) Inventor: John M. Vranish , Goddard Space Flight Center End effectors, or hands, for robotic arms have proved a limiting factor for efficient use of robot grippers. Mr. Vranish has designed an end effector that, with very low frictional forces, reliably guides, aligns, and seats an object without contaminating it. The device comprises a pair of gripper fingers that move towards each other to trap an object be- tween them. A centering roller positions and holds the object symmetrically about the X axis and clamping rollers position and hold it with respect to the Y and Z axes. For More Information Circ le No. 692. Superconductlng Bearings With Levitation Control Configurations (US Patent No. 5, 117, 139) Inventors:Yury Flom and James D. Royston , Goddard Center An innovative design and incorporation of Type II superconductors enhance the stabil- ity of radial superconducting bearings , pro- vide a means to counteract the effects of gravity on the rotating shaft, and permit levitation forces within the bearings to be varied. The bearing is designed for a shaft with magnets embedded at each end. A cylindrical hole is drilled into the supercon- ducting material and the shaft is inserted into it. The bearing exerts levitational forces on the magnets at both ends of the shaft. For More Information Circle No. 694. Solar Thermal Energy Receiver (US Patent No. 5, 113,659) Inventors: Karl W. Baker and Miles O. Dustin , Lewis Research Center A receiver designed for a solar heat man- agement system collects, stores, and dis- tributes heat to. a Stirling engine. Concen- trated solar energy is received by a collec- tion of heat pipes in a shell and stored in canisters on the pipes. Between the canis- ters and the engine heater head is a cavity through which the pipes extend to exchange heat with the heater head. The receiver provides uniform distribution of energy de- spite uneven impingement of solar energy on the heat pipes, absence of solar energy at times, or failure of one or more heat pipes. For More Information Circle No. 695. Method and System for Monitoring and Displaying Engine Performance Parameters (US Patent No. 5,050,081) Inventors: Terence S. Abbott and Lee H. Person, Jr., Langley Center Conventional aircraft instrumentation can result in cluttered control panels thai in- crease pilots' workload in reading and inter- preting the instrument output. The Langley system simultaneously monitors and dis- plays many engine performance parameters, permitting a pilot to make direct changes in thrust or power, and thereby to enhance performance. On a single display, the sys- tem calculates the differences between pre- dicted and actual parameter values, such as available thrust and thrust actually being produced, for multiple jet engines. For More Information Circle No. 690. 14 For More Information Circle No. 537 NASA Tech Briefs;- September 1992 The #1 Rated PrOject Manager Now Available For U1·ndows. Power changes people. Especially project managers. They're working smarter and faster with new CA-SuperProject® For Windows. It's the world's most advanced, efficient and reli- able project man- agement software - and now it's incredibly easy to use. Total power is yours with just a few mouse clicks. Create and edit 1 •• 2 LL Tota l Cosl projects. Specify resources, task ... Oaseline Ilrs types and durations. Define • • ro m M ary To III Cosl 60000 " tlOO O J6000 2" 000 12000 o Ilr" 00 m ... Tola l Ho urs integrated sub-projects. Build . . TOTAL S BY W (K top- .r:;" 0.19 g, 0.18 Conventional Q) ...J 0.17 Plecewise·Linear 0.16 Taper 24 22 20 C 18 Q) ~ Q) 16 Il. r§ 14 c: Q) 12 . ~ 10 W 8 6 4 2 180 176 Ordinal Number of Cavity Figure 2. The Cavity Lengths and the corresponding computed power-conversion effi- ciencies fer a traveling-wave tube with a conventional piecewise-linear velocity taper and a phase-adjusted taper. total cost of the traveling-wave tube. A pro- gram that computes the phase-adjusted taper contains a previously~eloped com- puter model of a coupled-cavity traveling- wave tube with additional code that cal- culates the gradually changing lengths needed to enhance efficiency. To represent bunching in the model, the NASA Tech Briefs, September 1992 Close links. ARIANESPACE : "Our aHachment to your business ensures you'll get our technological best". L aunching your satellite in the best environment is essential. When you select Arianespace, you select the world leader in commercial space transportation. You get a permanently available team of experts, state-of- the-art installations, an ideally-located equatorial launch site, and powerful launchers. Of course, all of this is dedicated to just one goal: the suc- cess of the last twenty minutes of our common mission. Today, all the main commercial satellites operators trust Arianespace. Confidence creates close links. For More Information Circle No. 589 Ariantspace, boulevard del'Europe, BP 177,91006 Evry Udex, Fl'1lnce, T~1. <33 I) 60 876000 luianespoce,1nc., 70013 10 Street, N.W., Sui .. 230 Washington, D.C, 20005 U.s.A. Tel. (202)628-3936 Hibiya un,raI Buildill8 1-2-9, Nishi-Shimbashl-Mina,(>-ku, Tokyo 105, Japan. Tel. (813) 35922766 electron beam is divided into a series of disks, each of which is divided further in- to four concentric rings. The trajectories of the rings and the amplitude and phase of the microwave field are determined from the calculated axial and radial electrical and magnetic forces arising from the dis- tributions and motions of charge in the rings and the interactions between these charges and circuitry as the rings pass along the sequence of cavities. The mag- nitudes and the phases of the bunches in the electron beam are taken to be those of the calculated fundamental Fourier com· ponents of current. Solutions are obtained by iteratively making integration passes of the equations of motion along the sequence of cavities until convergence of the microwave phase and amplitude is obtained. Typically, this requires about as many iterations as there are cavities. A ground-station satellite communica- tions coupled-cavity traveling-wave tube, operating in the uplink frequency band of the NASA.Advanced Communications Tech- nology Satellite (ACTS) and built according to the phase-adjusted taper design of Fig- ure 2, achieved more than twice the peak- power conversion efficiency of a baseline tube with a conventional piecewise-linear taper. The efficiency increased from 9.6 percent to 22.6 percent, a record value for a traveling-wave tube at a frequency above 20 GHz. The corresponding peak output power increased from 420 to 1,000 W. The main importance of the develop- ment of the phase-adjusted taper is that it very significantly increases the power capability of microwave transmission, thus enabling satellite-communication systems to have much higher data-transmission rates. This is especially important for the new high-frequency communications sys- tems because of the rapid increase of atmospheric attenuation with increasing frequency. The efficiency enhancement capability of the phase-adjusted taper will be especially valuable for communications coupled-cavity traveling-wave tubes used in satellites where power can cost up to $1 ,000,000 per watt. This work was done by Jeffrey 0. Wilson of Lewis Research Center. For further in- formation, Circle 33 on the TSP Request Card. Further information may also be found in NASA TP-2675 [N87-22923], "Revised NASA Axially Symmetric Ring Model for Coupled-Cavity Traveling-Wave Tubes." Copies may be purchased [prepayment required] from the National Technical In- formation Service, Springfield, Virginia 22161, Telephone No. (703) 487-4650. Rush orders may be placed for an extra fee by calling (800) 336-4700. LEW-14989 ~~CCD With Back-Side Illumination and Charge Steering Multiple frames could be recorded in rapid succession, without sacrifice of efficiency. NASA's Jet Propulsion Laboratory, Pasadena, California A proposed charge-coupled device (CCD) imaging array of photodetectors would have features of both a back-side-illuminated CCD and an interline-transfer CCD. The photoelectrons generated in each picture element of the array could be steered, by use of electrical control signals, to one of several nearby storage regions, without re- duction of the part of the back-surface area available for collection of charge. Thus, by suitable timing of the control sig- nals, charges from multiple image frames could be stored in rapid succession. Such a CCD could be particularly useful in im- aging such rapid transient phenomena as chemically reacting flows, with interframe intervals of the order of microseconds. As in a conventional back-side-illumi- nated CCD, the photoelectrons would be generated near the back surface and swept by electric fields toward the front surface into collecting potential wells, which would constitute the storage regions. As in a con- ventional interline-transfer CCD and unlike in a conventional back-side-illuminated CCD, the electric fields would include com- ponents parallel to the surfaces, so that the photoelectrons from each back-side location could be directed alternately to nearby storage regions that would not be directly opposite that location. The figure illustrates a three-phase ver- sion of the proposed CCD of the buried-n- channel type, in which the ability to steer electrons to two different storage regions in phase 2 would be imparted by the ad- dition of an internal p layer. The control sig- nals would be bias voltages applied to over- lying gate electrodes; by appropriate choice of these voltages, one could select either 30 Phase 1 Phase 28 Phase 3 Phase 1 Phase 2b Phase 3 10 Channel Stop ~ "Ii - 10 iii Bael< (Contains Implanted player) (Contains Implanted player) Oep1h of the two storage regions (2a or 2b) in phase 2. The sites without p layers in phases 1 and 3 would act as isolation re- gions that would prevent the flow of charge from selected storage regions (e.g., 2a) to the nearest nonselected storage regions (in this case, 2b). In the first frame of a typical operating cycle, phase 2a would be selected as the storage region, while phase 2b would be Channel Stop Phase 28 or 2b (WIth Implanted p Laye~ Biased To Store Charge (Selected) Front- The Implan- tation of an Additional p Layer in phase 2, com- bined with ap- propriate bias- ing, would en- able the appli- cation of elec- tric fields that would steer electrons to storage sites in phase 2a or 2b. deselected, causing photoelectrons gener- ated under six adjacent electrodes in phases 1, 2, and 3 to be collected in phase 2a. In the second frame, the biases on phases 2a and 2b would be interchanged, so that all subsequent photoelectrons would be collected in phase 2b. After integration of the second frame, the CCD would be op- erated normally, albeit with shifted biases, to transfer out the two frames of image NASA Tech Briefs, September 1992 Think of it as a mathematical playground for your mind. Open up a whole new world of scientific and engineering problem solving with Mathcad 3.1. Between the challenge of new problems and the reward of new solutions there is math. Often, a lot of math. Which is why we make Mathcad. It's the remarkable software that gives you the power to perform everything from simple arithmetic to advanced computational gymnas- tics more quickly, easily and naturally than with calculators, spreadsheets or programming alone. You use Mathcad just like a scratch with exponentials, differentials, cubic splines, FITs and more. Full symbolic calculation capabilities are available with a menu pick. So you can evaluate any integral, Taylor series or infi- nite sum just by clicking. Optional Electronic Handbooks * give you instant access to data, formulas and diagrams once found only in reference books. They're fully interactive. Just click and pa te tllem right into your document and work with them like any other text, value, table or formula. Or work with them right in the handbook itself. pad. Simply type your work anywhere in the live screen and Mathcad does the calculating. Change variables and Mathcad automatically updates the answers. It plots in 2-D -"-----S-.; ~ .,.,:,~. "~:,,,.,, . , . ; .... Plus optional Applications Packs with modifiable templates are avail- able for all major engineering and science fields. Over 200,000 satisfied '=- users. and 3-D. And prints your _""_--..:-.::"_-=---=- Each day, more engineers, scien- results, complete with text :::-'::'::==--Q5 71 tists and other technical profession- and graphics, in presentation - .~ / \ als discover that Mathcad opens up quality documents. • .. ,,,.! . r V a whole new world of freedom in Plus you see your work ::-7'_. u .'. • • t" ~ problem solving, and helps them more clearly because Mathcad . :::::=:= manage their time more efficiently. uses the same math notation \.r!'I!!!!!'l!!!""""''-"r;;:: Which is why in addition to being you would use with a pencil t the most popular math software you can buy, and. paper. it is also the most productive. It's the complete math system. • Microsott- Wmdows,TN Motif and Open Look Mathcad comes with more than 200 com- interfaces make Mathcad easy to leam and use monly used functions that let you quickly • Optional Electronic Handbooks include The CRC build even complex equations and formulas Materials Science and Engineering Handbook, Machine Design and Analysis from the StJl,ndJl,rd HJI,ndbook of Engineering CAlcullJtions(McGraw-HilI), and the Mathcad Treasury of Methods and Formulas • Optional Signal Processing Func- tion Pack contains over 60 functions including FIR and HR filter coefficients and power spectrum • Optional Applications Paw with adaptable tem- plates for Electrical. MeclJanical, c:ivil and Chemical Engineering, Statistics, Advanced Math, and Numerical Methods • PC Windows, PC DOS, UNIX- and Macintosh- versions available Free demo disk. For a free Mathcad demo disk, or upgrade informa- tion, call 1-800-628-4223, (or 617-577-1017, Fax: 617-577-8829). Or see your software dealer. 'E1caronic Handbooks rtquiK Mathctd 3.1. o 1992 M,thSofi. Inc. TM and ® signify mmufaaurcr's mdc:mm or rtgistcrtd ",demark rtSp«ti,~ly. 1-800-MATHCAD The answer is Mathcad® NTB 22 MathSoft, Inc. 201 Broadway, Cambridge, MA 02139 USA - Phone: 1-800-628-4223 - 617-577-1017 - Fax: 617-577-8829 A",1nIia: H ..... (OJ) 166 1766; IIcIpum: SClA 013/ 55 InS; Ilcnnwl.: EoSbcrJ 042·mm; FWand: Zcna 0-692-7677; Fnn«: U ....... 01-45·272061; G ...... y: Softtj", (0 71 02) 4OJ6; Italy: awu.d 02·9009InJ; ).p"': SMJ 03-5476·9816; SwaXn: AkadaniDo .. (011)2400 J5; Swhurland: _ 032 41 01 1\; UX: Adept Scientific (0462) 480055. I" ac Ioorali on. For More Information Circle No. 619 NTB992 Multiple Pages Intentionally Left Blank Thus, when the cables are struck by light- ning, the current divides among the shields and is conducted to ground along the path of lowest impedance. For example, if the strike is close to the cage and the cage is close to the ground, a major portion of the current flows along the shields of the ca- bles, through the backshell connectors, onto and over the surface of the cage, and through an arc to the nearest grounded object. Small portions of the lightning current can be carried by the inner conductors of the cables, which provide paths to ground via the equipment inside the cage. There- fore, transient-limiting devices are placed in these current paths to divert most of the remaining lightning currents to ground through the cage. The electrical require- ments for each piece of equipment to be protected determine whether the tran- sient-limiting device on the conductor con- nected to it is a gas-filled spark gap, a metal-oxide varistor, or a. hybrid consisting of a spark gap, a series impedance, and a silicon avalanche diode. This work was done by W Jafferis of Kennedy Space Center, R. r Hasbrouck of Lawrence Uvermore Laboratory, and J. P. Johnson of Sandia National Laboratory. For further information, Circle 82 on the TSP Request Card. KSC-11437 ~""'r--":::::::::::.. Shields Translent- Limiting Devices Equipment To Be Protected This Simplified Diagram of the Faraday Cage shows the essential protective and protected equipment. Metallic shields protect the conductors in the cables, and the equipment inside is protected further by transient-limiting devices. The new Elmo TSN270 Color CCO Camera is a double breakthrough ... Minimum illumination 01 2 lux and a very affordable price! Features ... Resolution is over 330 TV lines (H), selectable shutter speeds to 1110,000 sec, 46 dB SIN, CS and optional C mount lenses, buitt-in circuitry for aut(}iris lenses, aut(}white balance and N3C. The TSN270 Series is available in 24V ~, 12V DC, 120V ~ and a power to coax model for use with our acclaimed SSC-8C Too Page Quad Controller New Elmo low light CCD color camera - affordably priced. Compact in size, the 24V ~ model weighs a mere 17 oz. and measures 2%" square by 61h" long. Ask your CCN systems installer or distributor to demonstrate the superb new Elmo TSN270 Color Camera. 36 For fast action and ccmplete technical specs, call Vince Giovinco or any of our CCo/ITV experts at 1·800-654·7628. For More Information Circle No. 509 BLIW:D~~: 70 New Hyde Park Road, New Hyde Park, NY 11040 44 West Drive, Brampton, Ontario, L6T 3T6 Canada NASA Tech Briefs , September 1992 Generating Far-Infrared Radiation by Two-Wave Mixing Proposed devices would exploit the nonlinear dielectric susceptibilities of asymmetric multiple quantum wells. NASA's Jet Propulsion Laboratory, Pasadena, California Far-infrared radiation in the frequency range of about 1 to 6 GHz would be gener- ated by two-wave mixing in asymmetrically grown GaAs/AlxGa1_ xAs multiple-quan- tum-well devices, according to a proposal. Experiments in which second harmonics of the 10.6-pm-wavelength radiation from CO2 lasers were generated in such devices showed that the second·order nonlinear dielectric susceptibilities of the devices ex- ceed those of well-known nonlinear ma- terials (e.g., LiNb03) by factors of the or- der of 104. The proposal would exploit this large second·order susceptibil ity, which gives rise not only to radiation at the sum of the frequencies of two input waves (or double the frequency of one input wave as in the generation of second harmonics) but also to radiation at the difference be- tween the frequencies of two input waves. Devices of the proposed type could be used as tunable local oscillators in hetero- dyne·detection radiometers. The figure il- lustrates such an oscillator. liNo near-infra- red semiconductor diode lasers would be phase-locked, and one of them would be tunable. The outputs of these lasers would be amplified, then combined in a semi- conductor nonlinear multiple-quantum-well planar waveguide. A dichroic coupler may be necessary for efficient coupling of the two laser beams. All components would be integrated on one circuit chip. To maximize the amount of radiation gen- erated at the difference between the fre- quencies of the two lasers, it is necessary to optimize the design of the device with respect to three factors: (1) a high degree of confinement of the electromagnetic field in the nonlinear medium to maximize the power density, (2) phase matching to ex- t .55· l'm Slngle·Mode Diode laser tend the length of the zone of interaction between the two laser beams in the non- linear medium, and (3) the nonlinear sus- ceptibility. The device would be optimized with respect to the first two factors by de- signing and building it according to the techniques of integrated optics. For this purpose, the thin GaAs/AlxGa1_ xAs mul- tiple-quantum-well film would be consid- ered a nonlinear dielectric transmission line with transverse dimensions compar- able to the wavelengths of the signals to be mixed. The transmission line would sup- port transverse magnetic, transverse elec- tric, and transverse electric and magnetic modes, and the structure would control the dispersion of the various modes in such a way as to select preferentially the spe- cific sets of modes, at the related mixing frequencies, that satisfy the phase-match condition . Optimization with respect to the third fac- tor would be based on exploitation of ab- sorption resonances in the multiple-quan- tum-well structure in such a way as to obtain a large second-order dielectric susceptibili- ty. This, in turn, requires an asymmetric multiple-quantum-well medium, which can be fabricated by suitably varying such pa- rameters as the thicknesses of quantum wells and barriers and the aluminum con- tents of the barriers. This work was done by Shmuel Borenstain of Caltech for NASA's Jet Propulsion Laboratory. For further information, Cir- cle 45 on the TSP Request Card. Inquiries concerning rights for the com- mercial use of this invention should be ad· dressed to the Patent Counsel, NASA Resi· dent Office - JPL [see page 24}. Refer to NPO-18344. Sem iconductor Substrate This Integrated Optoelectric Circuit would generate far-infrared radiation at the beat frequency of the two diode lasers. PA89 Industry's Highest Voltage ±600V supply, 100nlA output 16Vhls s lew I'a te [Q= 6mA ma ' ±ttSOV MICRO·POSITIONING PA88/PA88M-High Voltage, Low Quiescent Current ±225V supply, 100nlA Oll tpUt 30 1 ~ls lew ra Le IQ = 2mA max P 88M-hi-rel military version RF PA85/PA85M-High Voltage, High Power Bandwidth ±225V lIpply, 200mA OULput ] 000 I [l s slew niLe 550kHz powe r bandwidtb PA85M- hi-r(,J military version ~--~ R INI +225V -225V DYNAMIC FOCUSING T APEX MI CROTECIINOLOGY CORPORATIO 5980 i\. han non Hoad, 1'u<80n, AZ 85i4 L Product and Applications ssis lance CaU 1-800-862-1032 or F (602) 888-3329 NASA Tech Briefs, September 1992 For More Information Circle No. 5 8 5 37 For da ... recording and ... orage sy ........ , Sony I. up 1'0 .... ndard. For More Information Circle No. 637 Electronic Systems ~~ Improved Zero-Crossing Detector Jitter is reduced substantially, and crosstalk is practically eliminated. NASA's Jet Propulsion Laboratory, Pasadena, California An improved zero-crossing-oetector cir· cuit is designed for precisely measuring the small difference (typically about 1 Hz) between the frequencies of two frequency- standard signal sources. The zero-crossing detectors of the best prior design exhibit a jitter of about 1 ps, which is large enough to impose a fundamental limitation upon the accuracy with which the frequencies of the latest ultra·high·stability sources can be characterized. Furthermore, the cross· talk between the prior zero-crossing detec· tors is so severe that the output of one such unit can induce a time offset of as much as 10-4 s in an adjacent unit. In the improved zero-crossing detector, cross· talk is eliminated for all practical purposes, and jitter is reduced to about 10 - 7 ps- the level required for state-of·the·art fre· quency·standard measurements. The two source signals to be compared are fed to a mixer, which puts out a sinus· oidal signal at the beat frequency. A zero· crossing detector transforms this sinusoid- al signal to a square wave or to a train of Sinusoid From Mixer ----. r---- " ---. Mixer rvv ! t ~ Slew Rate = 1 VIs Stage 1: Amplifier - ---. Bandwidth Mixer f\J\ = 1 Hz Gain = 20 ---. t pulses, which are sent to a conventional time-interval-measurement circuit. In a zero- crossing circuit of the older variety, shown at the top of the figure, the signal is first processed through a low·noise, low·band· width amplifier that increases its amplitude as much as possible without clipping. The signal is then sent to a broadband, limiting amplifier that "squares" the signal, pro- ducing leading and trailing edges that have short rise and fall times, respectively. The output of this amplifier is latched and sent to a driver, which feeds the final squared signal to the counter through a coaxial cable. The jitter in this circuit is caused by amplitude noise, and it depends on levels of noise, bandwidths of amplifiers, and in- stantaneous rates of change of signal volt- ages. Crosstalk is a parasitic effect of out- put ground currents. An improved zero-crossing detector, shown at the bottom of the figure, contains a low-bandwidth first-stage amplifier and three limiting amplifiers, each succeeding one of which "squares" the signal a little Stage 2: bit more. The design is optimized, with re- spect to minimization of jitter, by use of modern low-noise operational amplifiers and by suitable choice of gain and band- width for each stage. Crosstalk among zero-crossing-oetector units is eliminated by eliminating ground loops: input ground loops are eliminated by mounting each mixer in the chassis of the zero-crossing detector that it feeds; output ground loops are eliminated by replacing the output coaxial-cable feeds with fiber-optic trans- mitters. Even though the fiber-optic trans- mitter in each unit requires substantial cur- rent, these currents do not cause crosstalk because they do not flow among zero- crossing-detector units, but instead are contained within the chassis and power supply of each unit. This work was done by G. John Dick and Paul F. Kuhnle of Caltech for NASA's Jet Propulsion Laboratory. For further information, Orcle 2 on the TSP Request Card. NPO-18415 Stage 1: Limiting Amplifier Square-Wave Output Amplifier and Latch To Counter Via Coaxial Cable Bandwidth .JlJlJL = 1 Hz Operational Outpu t ~-.-- Amplifier f-o---- Driver Gain = 15 t t e-1 I Slew Rate Slew Rate = 15 VIs = Device Limit OLD Stage 2: Stage 3: Stage 4: O~\;~ Limiting Limiting Limiting Amplifier Amplifier Amplifier F; bo, .QpU, I Bandwidth Bandwidth Gain-Band- r-. = 100 Hz -+- = 20 kHz t-+ width -+- _ To Gain = 20 Gain = 100 = 80 MHz Transmitter Limits = ±5 V Limits = ±5 V Limits = ±5 V Counter t t t t Slew Rate Slew Rate Slew Rate Slew Rate Slew Rate = 1 VIs = 20 VIs = 400 VIs = 40,000 VIs = Device Limit of 107 VIs NEW These Zero·Crossing Detectors are typical of the older (above) and newer, improved (below) deSigns. The newer designs feature reduced jitter and essentially zero crosstalk. 40 NASA Tech Briefs , September 1992 Synthesized Function Generators SOMETHING NEW Every so often a powerful concept changes the way things are done. For a long time, function generators have been a jumble of analog circuits - ramp generators, YeOs, mixers, lim- iters and shapers. The new concept is Direct Digital Synthesis, and function generators will never be the same. The performance and features of these instruments is unrivaled. Each model provides synthesizer accuracy and res- olution, seamless sweeps over their en- tire frequency range, clean standard waveforms (sine, square, ramp, tri- angle), and a dirty one too (widebani gaussian noise). Distortion stays low even when driving 10 Yp-p into a 50 Q load. Seamless linear or log weeps The DS335's 3.1 MHz frequency range, I j..lHz resolution , and its clean (0.05% THD) and flat (±O.ldB) outputs, es- tablish it as an outstanding value at $995. An optional GPIB/RS-232 inter- face allows integration into automatic test applications. DS335's clean output spectra The DS340 is similar to the DS335, with a frequency range which extends to 15.1 MHz, and arbitrary waveforms. Arbs may be programmed with 12 bits of vertical resolution, record lengths to 16k points, and sample rates to 40 MHz. A linear phase filter provides smooth outputs with a 10 MHz bandwidth. DS33S DS345 offers AM, FM, PM and Burst modulation The DS345 has all of the features of the DS340 with frequencies up to 30.2 MHz, and a rich set of modulation capabilities. Any of the standard wave- forms may be amplitude, frequency, or phase modulated by sine ,squares, ramps, triangles or arbitrary modulation patterns. Several DS345's may be slaved together via an external clock in- put, and the phases between their out- puts may be adjusted with millidegree resolution. Three new synthesized function gener- ators. Outstanding performance. Unsurpassed value. DS348 DS34S Max Freq (Sine/Sq) 3.1 MHi IS.1 MHz 30.2 MHz Freq Resolution 1J.LHz Standard Timebase ±5ppm THO (fo=lO kHz) <0.05% Spurs (fo=l MHz) <-65dBc Level Accuracy ±{).IdB Modulation FSK Arbitrary Waveforms none GPIB/RS232 $395 Price $995 STANFORD RESEARCH SYSTEMS 1290 D Reamwood Avenue, Sunnyvale, CA 94089 TEL (408)744-9040 FAX 4087449049 For More Information Circle No. 445 IJ1Hz l~ ±Sppm ±5ppm <0.05% <0.10% <-65 dBc <-55dBc ±O.IdB ±O.2dB FSK AM.FM1PM, FSK,Burst 12 bits to 16k point and 40 Msamples/s $495 $495 $1595 $2195 Open-Loop Acquisition of Frequency in BPSK Precise symbol timing would not be necessary. NASA's Jet Propulsion Laboratory, Pasadena, California 2'(1) Integrate· and· Dump Filter Z(n) Estimated !11 The figure illustrates a proposed open· loop analog/digital Signal-processing sys- tem, part of which would produce an initial estimate of ("acquire") the carrier frequen- cy of a received binary-phase-shift-keyed (BPSK) Signal modulated by non-return-to- zero pulses. The system would be a Cos- tas·loop error detector that would function in a closed-loop manner overall; the term "open-loop" refers only to the frequency- acquisition function, in which neither phase feedback nor frequency feedback would be used. The initial estimate could then be used to initiate the closure of the fre· quency-control loop in that it would be used to adjust a numerically controlled os- cillator to a frequency sufficiently close to Input r(t) y)-_.... (n+l)T '!"'f ( )dt N·Point FFT Processor the true carrier frequency that it would lie within the pull-in range of the Costas loop. Initially, the numerically controlled oscil· lator would be set at a frequency offset by a specified amount from the nominal car- rier frequency. The incoming signal would be mixed with direct and OOo-phase-shifted outputs of the numerically controlled oscil- lator, yielding an in-phase signal i(t) and a quadrature signal q(t) (where t = time). Each of these signals would be passed through a one-pole low-pass filter, yielding l;(t) and lJt), respectively. l ;(t) and lq(t) would be mixed, yielding Z'(t), which would include noise plus a sinusoidal component at twice the difference between the car- rier and oscillator frequencies. The magnitude, but not the sign, of the frequency difference would be found by searching through the magnitude spec- trum of Z'(t). This would be done by use Numerically Controlled L-----i OSCillator V2 si n('do t + eO) T nT n T Closed for Tracking\ Open for Acquisi t ion) AcqUisition Frequency Corrector This Costas·Loop Error Detector, when starting to operate in the acquisition mode, would esti- mate the difference between the frequency of the input signal and that of an internal reference oscillator. The estimate could then be used to close the frequency-control loop. of aT-second integrate-and-dump filter (where T = the symbol period of the mod- ulation) followed by a fast Fourier transform (FFT). Because the amplitude of the double- frequency. 1 x 1Q4 s (where the measure of stability as used here is an upper limit on instability, as expressed in units of the root-mean-square fractional deviation of the frequency from the nominal value). In preliminary measurements, this clock has exhibited stabilities of 1.6X1Q-13/-.fi for 50 s < 7 < 800 s with an atomic resonance peak 160 mHz wide and a signal-to-noise ratio of 40 for each measurement cycle. Further analysis indicates that the sup- pression of instabilities contributed by vari- ous known sources could yield a stability measure of about 10 -16 for 7 ~ 106 s. This 'MJrk was done by John 0 Prestage and G. John Dick of Caltech for NASA's Jet Propulsion Laboratory. For further information, Circle 80 on the TSP Request Card. NPO-18382 NASA Tech Briefs, September 1992 ing modules, RTI boards can be used for the broad- est possible range of data acquisition applications. CyberResearch has now made this top-of-the-line product afford- able for every- one. By bundling an RTI 8l5A together with LABTECH NOTE- BOOKIiI software at one low price, ..... :..;:;: __ .......... iIII_ ..... CI.l:.:...iUI we've saved over Labtech Notebook $500 and made it possible for you to afford the very best. Each combination package includes: • RTI 8l5A data acquisition board configured for 32 Single-Ended or 16 Differential analog input channels with a 50KHz NO conversion rate, 2 analog output (D/A) channels , 16 Digital I/O lines, and 3 Counter/Timer I/O channels . The RTI series of data acquisition boards were de- • LABTECH NOTEBOOK menu-driven software signed by Analog Devices with industrial users in with new IconView diagramming user interface mind. With the lowest failure rate in the industry, these are the boards to choose when reliability is and drivers for controlling the RTI 815A board. critical. Designed from the outset to be compatible Order I RTl815LN RTI DAS Combination Package.$1995 Guarantee Valid Data with Signal Conditioning Modules Signal conditioning modules serve several purposes; they protect your computer, isolate your signal of interest from noise, amplify low-level signals, and provide power and eXCitation to transducers. One name is virtually synonymous with signal con- ditioning: Analog Devices. And CyberResearch is your Analog Devices distributor carrying every signal conditioning line: the versatile 3B series, the low-cost 5B series, and the new, intelligent 6B series wi~ on-board AID conversion. Call 800-4864400 to receive additional information. . W .. ith.~ .. e.fu. II. I.in.e.o.f ..... D .. ev. ic. e.s.' Ii .. I.c.o.nd. i.tion .. -.... F.o.r.~ .. o.r.e .. ln.f.o.r.m.atio~n.C~ir.c~l;e~N~o ••• 3~6~7 .. ~~~iili~;;illi~~~IiIi~iii;~ EASYEST LX Software trom Keithley I Metrabyte Easyest LX gives you an inte- grated set of tools for easy and effective implementation of a data acquisition and analysis system on any IBM-compatible PC. Each tool is represented by an icon, and the all-In-one screen puts everything in view for instant access. No other package lets you do so much, so quickly , so easily . • Acquisition & analysis combined • Control NO , D/A, Digital I/O, etc. • DMA acquisition at full speed of H/W • Analyze time & Irequency domains • All tools always displayed on screen • Call for free Demo Disk. I ASY 200 EASYEST LX Software w/1 Free DAS Board Driver .......... ........ ... . $995· • New, lower price NOW IN EFFECT. Save even more With CyberResearch! For ~ore Information Circle No. 360 Opto-Isolated RS-422 Converter Protects Your PC Your computer can be protected at the power supply. bu suffer a devastating shock from power surges picked up over long data lines The COMH 262 converter module from Telebyte Technology serves double- duty, providing both high-speed RS-232 to RS-422 conversion and optical isolation. • Optical Isolation exceeds 10,000 Volts • Earth ground conneclion • SWitch selection of DCE or DTE • LED status indicators on data lines • Wall transformer powers the unit • Data Rates to 19K baud over 2 miles • RS-232 Connector: DB-25 (select Male!Female) • RS-422 Connector' 4 screw terminals + ground t COMH 262 Isolated RS-232 to RS-422 Converter Module .... .. ...... .. .. ....... .. For ~ore Information Circle No. 370 New 19" Rack-Mount Computers & Peripherals CyberResearch offers a complete line of rack-mount computers and data acqUisition hardware. Low- cost EIA 19" rack-mount monitors. printers. surge protectors, industrial keyboards , UPS's, and other PC peripherals can seem impossible to find, but at CyberResearch. they've been a specialty of ours since 1984. Each of our new VRK rack-mount PC 's includes: built-In VGA color monitor, VGA card, pull-out industrial keyboard. floppy drive, & slide rails. I VRK 486·50 Rack-Mount 50 MHz 80486 PC wNGA Monitor, Rack-Mt. Keyboard. & 4 MB RAM .......... .. $4495 For ~ore I 48 :J The IR tic - a real infrared thermocouple ::. Noncontact temperature measu rement ::. Plug-compatible with any conventional tic measuring device :J Self-powered, smal l, and surprising ly inexpensive Call1-80G-422-3006. Find out how this unique technology can make a striking impact on your bottom line. Wdh the IR tic, excuses are hsssstory . .. 1992. heroen CorpOfal1Ol'l W. M. Berg, Inc 499 Ocean Avenue E. Rockaway , NY 11518 Tel. 516 596 1700 Fax 516599 3274 For More Informa'tion Circle No. 305 Open-Loop Acquisition of Suppressed Carrier Signals It is not necessary to synchronize with NRZ, BPSK symbols. NASA 's Jet Propulsion Laboratory, Pasadena, California Three digital techniques for the open-loop acquisition of suppressed carrier signals in the presence of binary-phase- shift-keyed (BPSK) modulation representing non-return-to- zero (NRZ) data symbols have been proposed. The tech- niques are intended mainly for use in the case of low signal- to-noise ratio , in which the offset, M, of the carrier frequency from the frequency of a numerically controlled oscillator in SIgnal From Numerically ContrOlled Oscillator Signa l From Numerically Controlled Oscillator Integrate· and-Dump Fil lers FULL-SYMBOL INTEGRATION HALF-SYMBOL INTEGRATION STAGGERED-SYM BOL INTEGRATION Three Techniques for Open-Loop Acqu isition of a suppressed carrier signal involve the use of FFT's to find a tone at twice the offset (error) frequency. NASA Tech Briefs, September 1992 LABORATORY HV SUPPLIES ••• to 60 kV and 45 W High performance and low cost DC high voltage are now available for the lab bench with the EL Series of tightly regulated , low ripple, and highly sta- ble power supplies. Voltage ranges are 0 to 3 kV through 0 to 60 kV. Oper- ating features include low stored energy for safety and an automatic crossover from constant-voltage to constant-current regulation for protec- tion from overloads, arcs, and shorts. Glassman High Voltage 100 W POWER SUPPLY TO 60 kV 3.5 in. and only 13 Ibs. The EH Series offer 100 W high volt- age power supplies of superior qual- ity in a compact and low weight package and at an affordable price. Rack panel height is only 3.5 inches and weight 13 Ibs. Standard features include local and remote control and monitoring, tight regulation , low rip- ple, and fast response. Voltage ranges are 0 to 1 kV through 0 to 60 kV. Posi- tive, negative, or reversible polarity models are available. Glassman High Voltage Call for full information on the MJ and MK Series, or other Glassman supplies,1 kV to 500 kV, 15 W to 15 kW. Innovations in high voltage poNef supply techn%g~ * ~SSL~~g~~~~ B~~~~hO~ $RUN C_tltAMPU . include . inclucM U.ncllMte deacrip ' " 1.10 .et. pAr_t.er definitions " / / " DEC1tTl r:out.ine denni-Liona "/ ' " auing deact'1pt.or ct.Hnltiona . / '0 STATUS value bit. deUnitiona 0' f Lnc 1 uda • t.ade f _In() < / . o.clara local vlIriable. - / Int. STATUS / . STATUS returned by LID routine call. 0' ,allY Id / . LIG-a .. lgned devlce ID 0' .da!;i lengl:h '" nu.ber of dat.a byte. t.o read 0/ , - ' " Declare t.he atring descript.ors tor the atrLng conat.anta " / $DESCRIPT'OfI (clew type. "AXAOI-,: , . AXVll·C device t.YJ* "' $DESCRIPTOR (.:xli atrUlCj. -lUY",: / - LGP$PLOT.ode nrin9 vdue -/ $DESCRIPTOR Ixla~l. "Time"'l / - LGP$PLOT x-axis label '/ SDESCRIPTOR Iybbel, ~Voltage"': / - LGP$PLOT y-axis label . / $DI:SCRIP'l'Oa It.it.le, "C_BXAMPLB"): /' l.oGP$PLOT quph tit.le ' / ,. Declare cUt.a buffer tor raw data in L8PSFOIlMAT TRANSLATE ADC. This is a IoOOcd (16-bit.) array containiDg 100 et ... nta . - ., ahort int raw_dat.at 1001; ,. Declare data buHer for voltage. in LSPSPOIUtAT ~SLA"E AOC .net LCP$PLOT routlne •. Thh is a .Ingle-precision, -floating-Point array containing 100 eleMnts • . , float. voltage.IIOOH ,- Proqr_ execution -/ / - Set up t.he AXVll-C -/ printtC"C_ZltAMPLE, Ita" data, convert. it, plot it.\n\n"" ,. Att.ach th. AXVl1-C and •• t up for .. pped I polled) I/O. This routine call returns an LIo-e •• i9nec! aevic. ID for the device • . , STATUS" LIO'ATTACH ,'axv {d, ideY t.ype. '1.10$1': KAPIl it(ICS,.AT1JS 'ST!SM_luca'!SI' LIBSSIGJllk{STATUS); / ' set. up the AJtVl1-C to lola. the .ynchronou. I/O interface. -J STATUS" LIOSS!'!' I "axv {d, '1.I05k SYNCS, ,Oil if (I (STATUS, STSSM_SUCCESS)) LUSSSIGNALCSTATUS); /' set up AXVll-C channel 2 for input. -/ STATUS" LtO.S" 1 I'.'" id. 'LI0Sk AD CHAN, ,t, '2,; lflltSTl1'US' SlfSSM_SUCCES1,,-LJ8UICNALCSTAroS): / ' Set up a channel gatn of 1. -/ STATUS" LIOSS!'!' t " .. v id, 'LI0SK AD CAl". 'I. 'I): if" (lTlTUS , S,"SSM_SUCClS'!II-LIBSSIGNAL(STATUS); " '!'rlQ'ier on LIOSUAD and fill bufCer •• f •• t •• po •• ibl •• - / STATUS .. 1.10$5" I (,.xv id, '1.1051(. 11tIG, 'I, 'LI05k IMM BI1R.S1'I: Hf I (STATUS , SfSllt_IucaS'!n LI8SSIGNALUT'lTUSI: DEC REALTIME INTEGRATOR MAKES IT SIMPLE. With DEC Realtime Integrator, you can be working with results in the time it takes you to wres- tle with syntax errors. Because as a complete graphical pro- gramming environment for realtime data acquisition and testing, it makes building an application as simple as draw- ing a picture. And since DEC Realtime Integrator is open , it lets you work the way you want to work. It can be used with IEEE- 488 and RS-232 instruments from any vendor - including Tektronix, Wavetek and HP and runs on any Digital VAX or RISC platform. Plus it allows you to send data to your favorite analysis and report-writing packages. For more information, includ- ing our free video " Realtime In No Time," call 1-800-DEC-RTI-1. And y ou'll see that setting up a test program doesn ' t have to be a te s t of "'D.Dn~D n.o your patience. ~ ~ U~ DIG I , A L. , H E OPEN A D V ANT AGE. @ DIGITAlEQUIPMENTCORPORATION 1992. THE DIGITAL lOGO, DEC AND VAX ARE TRADEMARKS OF DIGITAL EQUIPMENT CORPORATION. HP IS A TRADEMARK OF HEWlETI.PACKARD. TEKTRONIX IS A TRADEMARK OF TEKTRONIX, INC. WAVETEK IS A TRADEMARK OF WAVETEK CORPORATION. For More Information Circle No. 668 F2. The output from the photodetector gen- erates a signal that compensates for any drifts in phase by driving a piezoelectric cylinder around which fiber F2 is tightly wrapped. The controller steps the relative phase of the two beams in increments of 7r/2 radians by coarsely setting the phase to the desired value, alternating the polarity of the signal from the photodetector, and then locking onto the new phase. This work was done by Carolyn Mercer and Glenn Beheim of Lewis Research Center. Further information may be found in NASA TM-103252 [N90-28033], "Phase-Stepping Fiber-Optic Projected- Fringe System for Surface Topography ~~ Simplified Digital Spectrum Analyzer Measurements.' , Copies may be purchased [prepayment required] from the National Technical In- formation Service, Springfield, Virginia 22161, Telephone No. (703) 487-4650. Rush orders may be placed for an extra fee by calling (800) 336-4700. LEW-14996 Complexity and power consumed are less than those of other digital spectrum analyzers. NASA's Jet Propulsion Laboratory, Pasadena, California A spectrum analyzer (see figure) that consists mostly of digital circuitry computes approximate cross-correlations between a noisy input signal and a reference signal of known frequency, yielding a measure of the amplitude of the sinusoidal compo- nent of the input at that frequency. A se- quence of such correlations can be com- puted at different frequencies to obtain an approximate amplitude-vs.-frequency spec- rum of the input. essing stages are susceptible to aliasing of input components at 1/3 and 3 times the reference frequency). The filtered signal is fed to a zero-crossing voltage comparator, which acts as a 1-bit analog-to-digital con- verter in that it puts out a square-wave- like signal that is high if the input is positive or low if the input is negative. The squared signal is fed into two up/ down counters. One of the counters is clocked at the positive and negative sine peaks of the reference signal. It counts up if the input signal is positive at the positive peak or negative at the negative peak; it The input signal is first passed through an analog band-pass filter to reduce alias- ing (because the subsequent digital proc- Analog Zero-Croealng Input Band-Pass Voltage Filter 1---+ Comparator + Sine Peak -Sine Peak Sine and '-- Reference-Signal j----. CosIne + Cosine Peak Oscillator Generatol'a - Cosine Peak Other Up/Down Digital Counter 1---+ Processing Circuits Up/Down Counter + i This Spectrum Analyzer can be regarded variously as performing sampling, 1-bit cross- correlation, and filtering functions, all implemented by digital means. This block diagram is a simplified version: the spectrum analyzer as originally designed is more complicated and is part of an acoustic-signal processor. 54 .r: Q. "All of the C Language routines you need to write an impressive scientific graphing program of your own. Highly recommended" - PC Magazine 3114/89 m - High-resolution color output to most printers & plot- ,~ ters; PIC, GEM, EPS, HPGL, HPGU2 & TIFF files. v Source code gives you unimate control. Program- ming your own plots using GraphiC's high-level calls lets you communicate ideas, not just make pictures. Now available in Windows™ ~OS, and oOS-286 versions Scientific Endeavors 508 N. Kentucky St. , Kingston, TN 37763 (800) 998-1571 FAX: (615) 376-4146 ~ - -.:. Tim~ vibruion ft'IOCk J u -c28) Curnnt Drive EffICiency For More Information Circle No. 517 counts down if the input signal is negative at the positive peak or positive at the neg- ative peak. The other counter operates similarly, except that it is clocked at the positive and negative cosine peaks of the reference signal. If a sinusoid at the refer- ence frequency is present in the input, then a large count accumulates in one or both of the up/down counters if the sampling is continued during a large number of cy- cles of the reference signal. The magnitudes and signs of the counts indicate the approximate phase of the in- put sinusoid with respect to that of the ref- erence signal. The counts can be squared and summed to obtain an approximate measure of the power of the input sinu- soid. At the end of a sampling period, the counters are reset to zero. This digital sampling scheme can be regarded either as the accumulation of 1-bit cross correlations (the computation of which does not require multiplications, as multiple-bit correlations do) between the input and reference signals or as a digital filter. The bandwidth of the filter is inversely proportional to the number of cycles in the sampling period. In comparison with such other digital spectrum analyzers as those that compute fast Fourier transforms (FFT's), this one is simpler, consumes less power, and oper- ates faster. An FFT analyzer must perform many time-consuming complex multiplica- tions, using data from the entire spectrum to obtain any part of the spectrum. In con- trast, this spectrum analyzer performs no mulltiplications and, because it processes the data on each frequency independent- ly, can focus upon a narrow spectral range of interest without having to process data on the rest of the spectrum. This work was done by Steven W Cole of Caltech for NASA's Jet Propulsion Laboratory. For further information, Cir- cle 49 on the TSP Request Card. This invention is owned by NASA, and a patent application has been filed. In- quiries concerning nonexclusive or ex- clusive license for its commercial develop- ment should be addressed to the Patent Counsel, NASA Resident Office-JPL [see page 24}. Refer to NPO-17759. NASA Tech Briefs, September 1992 Books and Reports These reports, studies, handbooks are avail- ab le from NASA as Technical Support Pack- ages (TSP's) when a Request Card number is cited , otherwise they are available from the National Technical Information Service Acquisition Performances of QPSK Carrier· Tracking loops Times to, and probabilities of, acquisition are com- puted and compared. A report presents a comparative study of the acquisition performances of several types of carrier-signal-tracking loops for the reception of quadrature phase-shift keying (QPSK) signals. In this study, ac- quisition times and probabilities of acquisi- tion as functions of both the loop signal- ta-noise ratio and the ratio between the fre- quency offset and the bandwidth for each loop were obtained by computer simulation. The loops are classified primarily into three types: the maximum a-posteriori , (MAP) estimation loop, the Costas cross- over loop (also known as the polarity-type Costas loop), and the generalized Costas loop (sometimes denoted the conventional Costas loop). Each loop is classified fur- ther as being of type II or type III , de- pending on whether a certain parameter that appears in the z-domain transfer func- tion of a low-pass filter in the loop is or is not zero, respectively. Loops of the three primary types can be represented by a common block dia- gram, and differ in the processing of the in-phase and quadrature signals (Zc and ZS' respectively). The MAP estimation loop produces an error signal , ZO' given by Zo = Zctanh(RZs)-Zstanh(RZc) where R is the symbol signal-to-noise ratio. The MAP estimation loop requires a-priori knowl- edge of R and is best implemented with digital technology, but at the price of complexity. To reduce the complexity of the MAP estimation loop at high R, one can approx- imate tanh (Z) with sgn (Z) (where sgn(Z) = 1, 0, or -1 when Z > 0, = 0, or < 0, respectively). This yields the Costas crossover loop with error Signal given by Zo = Zcsgn (Zs)-Zssgn (Zc)' To reduce the complexity of the MAP estima- tion loop at low R, one can approximate tanh (Z) with the first two terms in its Taylor-series expansion to obtain Zo = Z~siZc 2 - Zs 2). This yields the generalized Costas loops. Both of these approximate loops can be implemented in a straight- forward manner and do not require a-priori estimation of R. However, all three loops require an estimate of the amplitude of the incoming signal to be able to operate at the desired bandwidth. NASA Tech Briefs, September 1992 In this study, a mathematical model of the signals in the various loops is devel- oped. In-phase and quadrature Signals are generated numerically and processed ac- cording to the various loop algorithms. Each simulation point is obtained by use of 5,000 runs for each combination of loop signal-to-noise ratio and frequency offset. The results of the simulation show that even though the MAP loop produces the smallest squaring loss at all signal-ta-noise ratios, the other two loops sometimes ex- hibit shorter acquisition time and greater probability of acquisition. This work was done by Sami M. Hinedi and Biren N. Shah of Caltech for NASA's Jet Propulsion Laboratory. To obtain a copy of the report, ''Acquisition Perfor- mance of Various QPSK Carrier Tracking Loops," Circle 60 on the TSP Request Card. NPO-18166 COME INTO THE NEW AID FAST LANE Announcing a new high in throughput that puts our Precision 5000 ahead of all other analog to digital conversion systems. .13 Mw/s, 12 bit words ± Y2 LSB. • 13 Mw/s, 16 bi t words ± 1 LSB. • 4 independent and concurrent sample rates. And you can drive latest technology. On-board data buffering. High-speed parallel interfaces for array processors and all popular busses. Go/no-go end- to-end calibration with diagnostics. 64 AID channels per mainframe, 1024 or more channels with multiple mainframes. Now, you can have advanced AID technology to go with our advanced anti-alias filter technology. Call, fax or write for more data on Precision 5000 and other Precision data acquisition systems. ~ PRECISION FILTERS, INC. 240 Cherry Street. Ithaca, New York 14850 60 7·m·3550 Fax: 607-277-4466 For More Information Circle No. 448 55 WOIfCItillllo ... GIld hfQh IMOUIon dIIpIayt. 1he -/VIeW CICCepIs video IignaII (NlSC or PAl) from a camera, tape recorder, vldeoclsc or built-in TV tuner. FUR Input Is also available. True color video Is displayed full screen or as a scaleable window. • Real time video under a" conditions • No impact on graphics performance • Image capture • Text and graphics overlays on video • Scale, reposition. freeze • X-Windows compatible • Cable ready tuner • Priced from $7500.00 Applications include 01, robotics, interactive videodisc training, video teleconferencing, process control, surveillance and simulation. Standalone peripheral and board level models available GSA Contract IiGS03F2032A ~.~ • SPECTRUM 950 Marina Village Parkway Alameda. CA 94501 Tel: (510) 814-7000 Fax: (510) 814-7026 For More Information Circle 469 56 Performance of Digital Data:rransition- Tracking Loop Coherent and incoherent sampling at various sampling and symbol rates are considered. A report presents a theoretical study of the performance of an all·digital data· transition·tracking loop (DTTl). DTTLs are used in those modern digital communica- tion receivers in which the modulation con- sists of nominally rectangular waves that represent binary symbols, and the changes in polarity, called "transition boundaries" between symbols, occur at the beginnings and ends of symbol periods. A DTTl is a subsystem that estimates the times of the transition boundaries in the effort to syn· chronize the functions of other subsystems of a receiver with the symbols. The DTTl can be designed to sample coherently (with its sampling clock con· trolled by the symbol·synchronization loop) or incoherently (with its sampling clock running freely at a rate that can differ from an integer multiple of the sample rate). In both cases, the DTTl can also be deSigned to sample either instantaneously or by the integrate·and·dump technique, which should be used when the number of sam- ples per symbol period is small. The theory presented in this study is valid for both instantaneous and integrate·and·dump sampling. For both coherent and incoherent sam- pling, equations are derived to analyze the effects of few samples per symbol period and of noncommensurate sampling and symbol rates. The effects of noise and the frequency response of the DTTl are taken into account. The effects upon the vari· ance of the phase error of the DTTl and on the mean time to lose lock are quan· tified through computer simulations. One of the conclusions drawn from the numerical results is that because of the phase ambiguity attributable to the period between successive samples, the digital DTTl performs poorly when the number of samples per symbol period is a small integer. This deficiency can be alleviated when the number of samples per symbol period is not an integer and the low·pass filter through which the phase-error signal in the loop is processed into a control signal for the sampling oscillator has the appropriate bandwidth. Another product of the study is a closed· form expression for the S,cuNe. This is the CUNe that shows the expectation value of the error Signal as a function of the phase error for a given signal·to-noise ratio and for a given offset of the first sample time mark in a received symbol from the tran- sition boundary. The S-cuNe is so named because it can take on any of a variety of shapes that resemble a sinusoid or the let· ter "S" lying on its side. The closed-form expression for the S,cuNe is valid for any number of samples per symbol period. Yet another product of the study is a demon· stration of the interplay between the band· width of the loop and the number of samples per symbol period in the reduc- tion of the phase ambiguity and of the self- noise, which is a component of noise that arises from the sampling process and is caused by a combination of timing and the finite number of samples. This work was done by Sami M. Hinedi and Unjeng Cheng of Caltech for NASA's Jet Propulsion Laboratory. To obtain a copy of the report, "Performance of the All-Digital Data Transition Tracking Loop," Circle 42 on the TSP Request Card. NPO-18176 Behavior of Costas Loop in Reception of Telemetry The modulation index, bit rate, subcarrier waveform, and subcarrier frequency affect performance. A report presents a study of the be- havior of a Costas loop in the reception of a binary non-return-to-zero telemetry signal phase-shift-modulated onto a sinus- oidal or square-wave subcarrier signal that is, in turn, phase-modulated onto a carrier Signal. The analysis applies to the case in which the received signal includes ad- ditive white Gaussian noise and may be Doppler-shifted and in which the carrier signal is not completely suppressed. This study extends a prior study that did not take account of phase-shift subcarrier modulation and the Doppler effect. Further- more, whereas the phase error of the Costas loop was assumed to approach zero at high signal-to-noise ratio (SNR) in the prior study, it is not assumed to do so in this study. Only the linear approxima- tion , which is valid for small errors, is in- voked in this study. Equations that describe the degradation of performance of the Costas loop in terms of phase jitter, conditions that cause loss of lock, and other effects are derived, and it is shown that the Costas loop can be used to track the telemetry signal with residual carrier in the presence of Dop- pler shift. It is found that the mean-squared tracking jitter increases when a residual carrier is present. The prinCipal parame- ters that affect the degradation of perform· ance of the Costas loop are found to be the telemetry modulation index, the telem- etry bit rate, and the waveform and fre· quency of the subcarrier. It is shown that the performance can be optimized by a suitable choice of the bit rate, the wave- form and frequency of the subcarrier, and NASA Tech Briefs , September 1992 the noise bandwidth of the filters in the arms of the Costas loop. Degradations of performance are com- puted in numerical examples that involve single-pole Butterworth arm filters and both sinusoidal and square-wave subcar- riers. For these examples, optimum values of the ratio between the noise bandwidth of the arm filters and the bit rate at a given integer ratio between the frequency of the subcarrier and the bit rate are determined. ~ (These values are optimum in the sense that they result in a specified mean-squared tracking jitter under a specified operating condition.) This work was done by Tien Manh Nguyen of Caltech for NASA's Jet Pro· pulsion Laboratory. To obtain a copy of the report, "The Behavior of a Costas Loop in the Presence of Space Telemetry Sig- nals," Circle 11 on the TSP Request Card. NPO-18290 Effect of Phase Unbalance in Product Modulator The performance of the carrier-tracking loop in a telemetry system is degraded. A paper presents a theoretical study of the effect of phase unbalance in the prod- uct modulator of the phase-modulation transmitter in a deep-space telemetry sys- tem upon the performance of the system. The purpose of the study is to determine the important parameters necessary for the design of a balanced product mod- ulator. Items of particular interest are the relationship between the undesired resid- ual carrier signal and the phase unbal- ance, the behavior of the carrier-tracking loop in the receiver under the influence of the phase unbalance of the product modulator In the transmitter, and the deg- radation of performance (in terms of the increase in the bit-error rate) caused by the phase unbalance. The product modulator is mathematical- ly modeled as two amplitude modulators excited in oppOSition, plus a subtractor, operating on a carrier signal. When the two amplitude modulators are perfectly bal- anced against each other, the output is the product of the carrier signal and the mod- ulation; the carrier is fully suppressed. In practice, perfect balance is not attainable. The phase unbalance - the inequality between the phases of the outputs of the two amplitude modulators - gives rise to a residual carrier signal in the output of the subtractor. The mathematical model of the product modulator is used in this study to derive equations for the relative strengths of the desired suppressed-carrier component and the undesired residual-carrier component of the transmitted signal. A computer sim- ulation to determine the degree of suppres- sion of the carrier is described, and its results are compared with the values given by the equations at values of phase im- balance from 1 ° to 12° in 1 ° increments. The simulation and the equations agree within 2 to 3 dB in all cases. It should be mentioned that the computer simulation gave results different from those of the equations derived in the paper for carrier suppression because the FFT algorithm employed in the simulation did not include the "zero-padding procedure for imporved frequency resolution . As a result , the loca- tion of the unsuppressed carrier compo- nent does not fall exactly on the carrier fre- quency and this gives rise to the error. Next, the study addresses the effect of the unsuppressed-carrier component on the carrier-tracking phase-locked loop in the receiver. A stochastic differential equa- tion that describes the dynamic behavior of this second-order phase-locked loop in the presence of the unsuppressed-carrier component is derived. Because this equa- tion is nonlinear and very difficult to solve, a computer simulation is performed, using representative parameters of a receiver in the Deep Space Network. It is shown that if the phase unbalance is sufficiently large, the carrier-tracking loop can lose lock on the suppressed-carrier component and lock onto the unsuppressed-carrier com- ponent. Next, the study addresses the ef- fects of the unsuppressed-carrier compo- nent on the bit detector in the receiver: equations for the bit-error rate as a func- tion of the phase unbalance are derived. The study concludes by presenting the following recommendations: • The phase unbalance should not lie out- side the range of ± 2°. • The minimum suppression of the carrier should be 35 dB. This work was done by Tien M. Nguyen of Caltech for NASA's Jet Propulsion Laboratory. To obtain a copy of the report, "The Impact of the Phase Unbalanced Product Modulator on the Performance of the Space Telemetry System," Circle 39 on the TSP Request Card. NPO-18293 APOLLO COMMEMORATIVE POSTER- Actual size: 30" x 21 " In Full Color! Printed on quality poster stock. Price only $8.95 each plus $5.00 for shipping and handling. (NY reSIdents add sales tax to total) Mail payment to NASA Tech Briefs, September 1992 NASA Tech Briefs, Dept. F, 41 East 42nd St., New York, New York 10017 For credit card orders call : (212) 490·3999 • AdJustment free auto-locking to or. workstations, Pes and Mac: lis o Interlaced and non-Interlaced Inputs o Pan, scroll and zoom o Flicker-tree output • Video overlay capability o Full 24 bit color • Genlock • RS-232 control • Broadcast quality NTSC/ PAl composite video S-Video, RGB RS-170/EBU, Y, R-Y, B-Y • RGB 31 .5 kHz tor video projection • Other models tram $10,995 GSA Contract #GS03F2032A SPECTRUM 950 Marina Village Parkway Alameda, CA 94501 Tel: (510) 814-7000 Fax: (510) 814-7026 For More Information Circle No. 479 57 Physical Sciences ~~ Multilayer Monochromator for Hard X Rays and 'Y Rays Advantages include compactness, high spectral resolution, and relatively low cost. Marshall Space Flight Center, Alabama A compact monochromator for hard x rays and 'Y rays provides high spectral resolution with high throughput. This in- strument can be fabricated with relative ease and at relatively low cost. It is easily maintained in alignment and capable of operating at any photon energy from about 8 to about 140 keV. The hard-x-raY/'Y-ray monochromator could be used in nuclear, astronomical, and biomedical research, x- ray crystallography, research on the proc- essing and properties of materials, research in x-ray lasers, and x-ray lithography. This monochromator (see figure) resem- bles the instruments described in "Com- pact X-Ray and Extreme-Ultraviolet Mono- chromator" (MF&28499), "Scanning X-Ray or Extreme-Ultraviolet Monochromator" (MFS-28492), " Ultra-High-Spectral-Reso- lution X-Ray/EUV Monochromator" (MFS- 28500), and "Four-Mirror X-Ray and Ex- treme-Ultraviolet Monochromator" (MFS- 28498), NASA Tech Briefs, Vol. 15 NO. 6 (1991), page 44. Like the monochromators of the previous articles, this one operates on the principle of the multilayer Bragg reflector. To restate the principle briefly: Alternating layers of high- and low-atomic- number material in a multilayer coat con- stitute a synthetic Bragg crystal , which reflects radiation in a narrow spectral band about a peak-reflection wavelength, x" given by NX, = 20 sin 8, where N is the order of the Bragg diffraction (usually 1), o is the effective thickness (corrected for refraction) of a high-atomic-number/low- atomic-number pair of layers, and 8 is the angle between the incident beam of radia- tion and the surface of the multilayer mirror. For operation in the spectral range from 8 to 140 keV, it is necessary to use a mul- tilayer coat with 0 "" 15 A and glancing This Reflecting Monochromator contains a multi- layer Bragg reflec- tor that acts as a wavelength-se- lective mirror for soft x rays and y rays. For opera- tion in the photon- energy range of 8 to 140 keV, multi- layer spacings are of the order of 15 A, and e typically ranges between 3° and 10 arc sec- onds. / Incident Polychromatic Beam angles, 8, ranging from 3° down to 10 arc minutes. The mirror substrate on which the multilayer coat is to be deposited must be long and flat enough for use at the low glancing angles, must be sufficiently rigid to maintain its flatness to within 1/100 wave- length of visible light, must have a low coef- ficient of thermal expansion, and must be polished smooth to a fraction of an ang- strom. For these purposes, the substrate can be made of sapphire or silicon carbide slabs, typically 1 cm wide, 12 cm long, and 4 cm thick. By use of advanced flow-polish- ing methods, it can be polished to a smooth- ness of 0.2 to 0.5 A coot mean square. A metal-foil filter is placed in the input aperture of the monochromator housing to block visible, ultraviolet, and soft x-ray Reflected Monochromatic Beam Housing photons, which may also be produced by the source of hard x-rays and 'Y rays. It is especially important to select foil ma- terials and thicknesses to block soft x rays because the small angles of incidence can be less than their critical angles, causing these rays to be reflected along with the desired hard x rays or 'Y rays. This work was done by Richard B. Hoover of Marshall Space Flight Center. For further information, Circle 13 on the TSP Request Card. Inquiries concerning rights for the com- mercial use of this invention should be ad- dressed to the Patent Counsel, Marshall Space Flight Center [see page 24]. Refer to MFS-28497. Charge-Carrier-Scattering Spectroscopy With BEEM Scattering of electrons and holes can be measured with spatial and energy resolution . NASA's Jet Propulsion Laboratory, Pasadena, California Ballistic-electron-emission microscopy (BEEM) constitutes the basis of a new spec- troscopy of the scattering of electrons and holes. This spectroscopy provides meas- urements that characterize the scattering process with both energy and spatial reso- lution. It has been used to investigate trans- port phenomena, scattering phenomena, 58 and the creation of hot charge carriers in Au/Si and Au/GaAs metal/semiconductor microstructures. In BEEM, a sharply pointed tip electrode scans near the surface of a coat of metal about 100 A thick on a semiconductor. The prinCiple of operation is similar to that of a scanning tunneling microscope, ex- cept that the metal coat acts as a third electrode. The figure shows energy diagrams for operation in the BEEM mode for both p- doped and n-doped semiconductor sub- strates coated with thin layers of metal. The tip electrode injects ballistic charge carriers into the metal via quantum-me- NASA Tech Briefs, September 1992 HI JetPro: A days work in under an hour. • • • • • • • 9:00 AM • • • • • •• A- to C-Size CAD Plots No more waiting for pen plotter check plots. HI jetPro Series V1 00 and V50 plotters create HP-GLTM/2, HP-GL and DMjPLTM CAD "review plots" at 360 dpi in under five minutes! No options needed. Includes real and protected mode ADr drivers. 9:30 AM ••• Documents • • HI jetPro Series emulates the IBM~ Proprinter™ XL24 to create high quality reports and letters from a wide range of word processing packages. - A A . . .. - • • • • • • • • • • • • • • 9:05 AM FAX Output HlJetPro V1 00 outputs FAX/modem files directly for highfesolution A- to C-size plain paper copies. Optional sheet feeder for A- and B-size output. ••• • 9:10AM • • • • Spreadsheets C-size and rollfeed capability allow you to create large, readable spreadsheets. Drivers are available for Windows™ 3.0 and 3.1 compatibility. • • • • 9:15 AM 1 .. :-... . .. .. .. '. • • • • Multiple Review Copies For meeHngs create A-size review copies in one minute; high- quality, C-size review .. copies in under five minutes. I Scanner Output HI jetPro V1 00 automatically reads and outputs high-resolution, scanned, raster images from hand-held (PCX), desktop [TIFF) and large-format scanners (RlC and CAlS). At a fraction of the cost of electrostatic plotters . • Project Schedules The rollfeed accessory allows long project management charts to be plotted from rolls of opaque or translucent bond paper. 9:50 AM •••••• Presentation Charts • • • • • • There's even time len to do large-scale charts for a 10:00 AM presentation. For information on HI jetPro Series plotters, or the nome of your local dealer, call 1-800-444-3425. New HI JetPro Series Plotters. HOU~ TNSTRUMENf® Every decision should be this easy.~ © 1992 Summagraphics Corporation. Seymour. CT 06483. All rights reserved . For More Informat ion Circle No. 550 >- Ol Q; c: w Bottom of Conduction Band Fermi Level of Tip Under Positive Tip Bias Fermi Level Under / Negative Tip Bias Fermi Level of Metal and 1---------..., ___ / Semiconductor >-e> CD c: w c: Fermi Level of Tip Under Negative Tip Bias Bottom of Conduction Band Fermi Level Z ~ of Metal and t--~:--~ __ ~ Semiconductor Top of Valence Band e I I ~ __ ..!...J 10 ° Topol w j I Valence Band ~ .. : I" W -TiP-I LMetal-l--semlconductor---_ Tip I-- Metal----1--Semiconductor- I Position - Electron o Hole I Position p-DOPED SEMICONDUCTOR n-DOPED SEMICONDUCTOR In the Usual BEEM Mode, the tip is biased positive to inject holes (in the case of a p-doped semiconductor) or negative to inject electrons (in the case of an n-doped semiconductor). In the new spectroscopic mode, the bias is reversed to obtain measurements indicative of scattering in the metal/semiconductor microstructure. chanical tunneling. Some of these carriers can propagate, without scattering, to the Schottky barrier at the interface between the metal and the semiconductor, where they can be collected as majority carriers in the semiconductor. In this respect the metal is analogous to the base of a tran- sistor. Therefore, an n-doped semiconduc- tor can serve as a collector for electrons, while a p-doped semiconductor can col- lect holes. In each case, if the polarity of the bias voltage on the tip is reversed, bal- listic current of carriers of the opposite type does not flow because the built-in Schottky-barrier potential opposes the bal- listic motion of the carriers and does not block leakage of minority carriers back into the metal. Now the principle of the new spectros- copy will be explained for the case of the p-doped semiconductor. Although ballistic electrons would not ordinarily be collected, scattering could create holes for collec- tion, even under reverse tip bias. As shown in the left half of the figure, negative bias on the tip causes the injection of hot elec- trons into the metal. While some of these electrons reach the Schottky barrier with- out scattering, others lose energy in scat- tering on conduction electrons in the con- duction energy band in the metal. The scattering excites the conduction-band elec- trons to energies above the Fermi level, creating hot holes in the metal. Some of these holes cross the Schottky barrier and are collected in the valence band of the semiconductor. When the tip is biased positive as in the usual BEEM mode, hot holes are injected into the metal directly by quantum-me- chanical tunneling. Like the hot holes creat- ed by scattering, some reach the Schottky barrier and are collected. Analogous proc- esses of injection of holes and electrons, scattering, and collection of holes occur in the case of an n-doped semiconductor. This work was done by Michael H. Hecht, Lloyd D. Bell, and William J. Kaiser of Caltech for NASA's Jet Propulsion Laboratory. For further information, Cir- cle 93 on the TSP Request card. NPO-18411 H igh.:remperature Tribometer and Data-Acquisition System Data on friction and wear can be acquired and processed quickly. LEwis Research Center, C/eve/and, Ohio A new friction-and-wear test rig (tribome- ter) at NASA lewis Research Center, Cleve- land, Ohio, tests the friction and wear prop- erties of ceramic and metal materials at temperatures up to 1,200 °C in controlled atmospheres. The tribometer was designed to help develop high-temperature lubricants and self-lubricating composite materials for such advanced applications as Stirling engines, advanced gas turbines, seals and bearings in hypersonic vehicles, and low- heat-rejection engines. The tribometer can be set up in a pin-on- disk or pin-on-ring configuration (see Fig- ure 1). It can rub materials in unidirectional sliding at speeds that range from 0.025 to 22 mls and in oscillatory sliding at frequen- cies up to 4.5 Hz at amplitudes up to ±60° (±13.3 cm). The test atmosphere is estab- lished by flow of a purge gas at a controlled rate. All components within the test cham- 60 ber are compatible with oxidizing, inert, or redUCing gases. Test loads can vary from 0.1 to 100 kg. The tribometer is connected to a data- acquisition system that uses computer pro- grams developed specifically to enhance the productivity and convenience of the testing facility. The data-acquisition system is based on a personal computer (PC) with an IEEE 488 interface. Specialized pro- grams were written in an expanded form of BASIC. The programs record average values of data that would normally be read from meters and chart recorders. The data are automatically stored in usable form and can be easily manipulated and plot- ted after each test (see Figure 2). The programs automatically compen- sate for minor run out (misalignments or geometric nonuniformities) of specimens and for thermal gradients in the test cham- ber. One program is written for unidirec- tional sliding and uses computer-gener- ated timing to trigger the acquisition of data; another program written for oscil- latory sliding uses an electronic position signal from the rig to trigger the acquisi- tion of data. The programs are easy to use. Input parameters like the duration and fre- quency of acquisition of data are selected by the user. With this new tribometer and its data- acquisition system, the friction and wear properties of many new materials and lu- bricants can be ascertained accurately and conveniently. This type of information is needed in the development of materials for advanced aerospace and terrestrial applications. This work was done by Harold E. Sliney and Christopher Dellacorte of Lewis Re- search Center. Further information may NASA Tech Briefs, September 1992 AEROSPACE KorweMi,ya in the Ex-USSR TAG lnUlInationtd ANNOUNCES PUBlICATION OF II COMPREHENSIVE GUIDE: DOING BUSINESS WITH SOVEREIGN SOVIET REPUBLICS II THE FALL OF THE USSR NOW ENHANCES - VIA MASSrvE MILITARY- INDUSTRJAL CONVERSION - ACQUlSlTlON OF AEROSPACE HARDWARE AND TECHNOLOGY FROM PRJV ATIZED SOURCES. PREPARED BY TAG'", OFFICE OF TECHNOLOGY ASSESSMENT WITH STRATEGIC INPUT BY C.LS. SPACE AND MISSILE EXPERTS, THE GUIDE OFFERS FIRST- HAND ANALYSIS OF AN EMERGING ECONOMIC ORDER, wrTH SPECIAL FOCUS ON C.LS. INTERSTATE SPACE aJUNClL ACTIONS AND RUSSIAN SPACE AGENCY ACTMTIES. TIDS aJMPREHENSlVE GUIDE EXPLAINS RULES AND REGULATIONS FOR TRADE AND TECHNOLOGY TRANSFER, DETAILS "CASE STUDIES" OF DESIGN BUREAU/WESTERN JOINT VENTURES, DECIPHERS THE AEROSPACE INDUSTRY CONVERSION PROCESS, AND DISSECTS C.LS. SPACE ARCFllTECTURE. ANALYSIS OF NEWLY FORMED AEROSPACE JOINT-STOCK COMPANIES AND C.LS. POLEMICS RESULTING FROM KorweMya OF STATE- TO PRIVATELY-QWNED ENTERPRISES IS OFFERED. E~ 0& ~ Souwe6 PRIDNEPROVSKY SPACE EXCHANGE UKRAINE MINISTRY OF SPACE INDUSTRY RUSSIAN SPACE RESEARCH INSTITUTE PATON (KIEV) INSTITUTE OF SPACE WELDING RUSSIAN MINISTRY FOR ECOLOGY & RESOURCES ENERGIA DESIGN BUREAU ZVEZDA SPACESUIT (JS) COMPANY C.I.S. COUNCil ON PRIVATIZATION KAZAKHSTAN SPACE COUNCil GAGARIN COSMONAUT TRAINING CENTER RUSSIAN COMMITTEE FOR DEFENSE CONVERSION PARTIAL TABLE OF CONTENTS OVERVIEW: MILITARY- INDUSTRIAL "FIRE SALE" FREE MARKET vs TECHNOLOGY CONTROL PROPER PERSONAL & BUS~ PROTOCOL ANALYSIS: NASA/C.I.S. 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CASE STUDIES, $$ EXCHANGE INFO, etc. PART V - CUSTOMS & BORDER CONTROLS PART VI - FRAUD & LEGAL PROTECTION To Order , Send Coupon Below to: WILLI&~ W. JOHNSON, Chief Editor TAG INT'L, CIS Business Affairs, PO Box 1808, Southlake, Texas 76099-1808 USA FOR FAX ORDERS AND ADDITONAl INFORMATION: (817) 481 - 1361 YES!! SEND THE MOST CURRENT C.I.S. SPACE and BUSINESS INFORMATION. PLEASE FORWARD __ COPY(S) OF "COMPREHENSIVE GUIDE: DOING BUSINESS WITH SOVEREIGN SOVIET REPUBLICS" AT A SPECIAL PRE- PUBLICATON PRICE OF $195 USD EACH (REG.$250 AFTER 9/23/1992) NAM[ ____________________________ __ o PAYMENT ENCLOSED CHARGE MY: 0 MASTERCARD 0 VISA 0 AMERICAN EXPRESS TiTle ____________________________ __ CARD 1# ___________________________ EXp __ _ COMPANY ________________________ ___ SIGNATURE __________________________________ _ ADDR[SS __________________________ _ PHONE ___________________ FAX ______________ __ CITY ____________________________ _ o PLEASE SEND FALL LJpD~ K4;e STATe/ZIP __________________________ _ ($55 in 11/92. AlL PRIC[S INCLUD[ SU"JPING CHARG SI For More Information Circle No. 627 I 1.0 '0 C 0.4 (1) 'u ~ 0.2 o u o Sliding Time, min Figure 2. The Computer Generated This Plot from data taken in a test of oscillatory slid- ing of carbon/carbon composite specimens at a temperature of 1,200 °C. 17811], "The Application of a Computer Data Acquisition System for a New High Tem- perature Tribometer." Figure 1. The The High-Temperature Trlbometer is shown here in the pin-on-disk Copies may be purchased [prepayment required] from the National Technical In- formation Service, Springfield, Virginia 22161, Telephone No. (703) 487-4650. Rush orders may be placed for an extra fee by calling (800) 336-4700. configuration. be found in: NNSA TM-102405 [N-ro12670], ':,4 New Test Machine for Measuring Fric- tion and Wear in Controlled Atmospheres to 1,200 °e," and NASA TM-102S08[N-ro LEW-15362 Measurement of Residual Stress in Ferromagnetic Materials MAC and MAE techniques are combined to characterize stresses completely. Langley Research Center, Hampton, Virginia Complete and accurate characterization of residual stress is one of the most trouble- some problems in the field of nondestruc- tive evaluation. A technique developed by NASA, called the " magnetoacoustic" (MAC) technique, can be used to detect residual compression in ferromagnetic materials, without having to use calibra- tion standards. The MAC technique, how- ever, does not enable the detection of re- sidual tension in a ferromagnetic material. A newer technique, called " magneto- acoustic emission" (MAE), has been clear- ly shown to provide a capability to detect residual tension. The MAE and MAC tech- niques have now been combined to pro- vide for the complete characterization of residual stresses in ferromagnetic struc- tural materials. The implementation of both techniques involves some unique instru- ments and methods developed at NASA Langley Research Center. In the MAE technique, one uses a broad- band acoustic transducer for passive de- tection of acoustic noise generated by the motions, induced by an external ac mag- netic field, of the walls of magnetic do- mains. The results of experiments have shown that this effect is sensitive to the magnitude of tensile stress. The effect of compressive stress on the generation of MAE is very small. While the insensitivity of MAE measurements to uni- axial compression is usually an advantage, 62 Differential Amplifier Power Supply Amplifier Analyzer Digitizer Preamplifier MAE Instrumentation is connected with a desk-top computer to determine the spectral characteristics of MAE. it can also be a disadvantage in that a state of high compression can be mistaken as a state of a low tension. To avoid this mis- take, it is necessary to know whether the object being tested is under residual com- pression, which condition can be detected easily by use of the MAC technique. In the MAC technique, one measures the changes in the natural speed of sound in the material as a function of net mag- netization induced in a ferromagnet. For MAC measurements, narrow-band acous- tic transducers are used. The difference between the phases of the transmitted and received acoustic waves is proportional to the transit time of the acoustic waves in the specimen, which time is directly re- lated to the speed of sound. The instrumentation developed at lang- ley Research Center (see figure), called "pulse-phase-Iocked-loop" (P2L2j, is used for automated measurements of normal- NASA Tech Briefs , September 1992 .. Vat a e ow. THE WORLD'S FIRST AND ONLY Intioducing LABTECH's True Real-Time Multitasking Software for Windows 3.1 :: Only LABTECH®'s TRUE real-time multitasking software for Microsoft® Windows'· lets you see it when and as it happens. AND IT'S AVAILABLE NOW! This allows you to do real- time acquisition and control, while simultaneously running other programs. :: YES, WE'VE DONE IT AGAIN. We've made it easy for you to collect, display and log data, while making all control decisions with TRUE real-time information. :: WE'VE GOT YOU COVERED. Offering 1 khz data acquisition in Windows enhanced mode. And compatibility with nearly all data acquisition hardware. :: NOW IT'S YOUR MOVE. To order, simply dial 1-800-TRY- LABTEC H and say, ''I've seen llili the light," and we'll send you a free large full-color TRUE real-time poster. LABTECH ~ LABORATORY TECHNOLOGIES CORPORATION 400 Research Drive, Wilmington, MA 01887 Tel: (508) 657-5400 Fax: (508) 658-9972 LA.BTEC H is a registered trademark of Laboratory Technologies Corporation. Microsoft is a registered trademark and W indow s is a trademark of Microsoft Corpo ration. For More Information Circle No. 423 ized changes in the speed of sound in the specimen. The parameters measured are the fractional changes in frequency nec- essary to maintain the constant difference between the phases of the transmitted and received waves as the speed of sound changes. The changes in frequency are measured by a frequency counter, which is connected with a desk-top computer. The combination of the MAC and MAE techniques makes it possible to character- ize residual tension and compression in structural ferromagnetic materials without being limited by surface conditions and unavailability of calibration standards. Such a development is significant in the field of characterization of materials as well as in the detection of fatigue failure. This work was done by Min Namkung and William T. Yost of Langley Research Center, Peter W Kushnick of l.JJckheed Engineering and Sciences Co., and John L. Grainger of Analytical Services and Material, Inc. No further documentation is available. This invention is owned by NASA, and a patent application has been filed. In- quiries concerning nonexclusive or ex- clusive license for its commercial develop- ment should be addressed to the Patent Counsel, Langley Research Center [see page 24]. Refer to LAR·14239. ~J Four-Sector Cylindrical Radio-Frequency Ion Trap Features would include relatively large ion-storage capacity and shielding against external fields. NASA's Jet Propulsion Laboratory, Pasadena, California A linear radio-frequency ion trap of cy- lindrical configuration has been proposed. Such radio-frequency traps are used prin- cipally in frequency-standard laboratories to confine 199Hg + ions electrodynamically in isolation from the external environment. The long confinement in isolation reduces fluctuations in frequency by suppressing perturbations of atomic energy levels. The device is similar to that described in "Linear Ion Trap for Atomic Clock" (NPO-17758), NASA Tech Briefs , Vol. 14, No. 9, (1990). The proposed trap would consist of a closed metal cylinder partitioned into four equal cylindrical-sector electrodes and two circular end electrodes (see figure). The radio· frequency voltage would be applied to each cylindrical-sector electrode with a polarity opposite that of the adjacent cylindrical-sector electrodes. In addition, dc bias voltages could be applied to vari- ous electrodes with respect to each other or to ground. When applied to the cylin- This Radio-Frequency Ion Trap would be made by dividing a hollow metal cylinder into four cylindrical electrodes with two end-electrodes. Radio-frequency voltages would be applied in alternating polarity (± v..c) to the cylindrical-sector electrodes. End Electrode -Vac Tough Environments. Tougher Recorders. 64 The DV 6000 Series helical scan recorders are built from the ground up to operate in the harshest environments. That means using MIL-Spec ICs, vibration-isolated tape transports, built-in temperature compensation, EMI/RFI shielding, and even special composition circuit boards. What all this gives you is a choice of rugged airborne or ground-based recorders that provide error-free operation, from 2.5 Mbps to 240 Mbps, with selectable playback rates, built-in test, and compatibility with MIL-Std 2179B and ANSI 10-1. The DV 6000 Series digital recorders. High-speed, error-free performance. On the ground, in the air, in any environment. For further information, please contact: Loral Data Systems, Data Recorders Division, P.O. Box 3041, Sarasota, Florida 34230; or call (813) 378-6747. LCiRAL Data Systems For More Information Circle No. 477 NASA Tech Briefs, September 1992 drical shells, the effect could be to alter the trapping-potential field (for example, a gravitational offset for macroparticles) with dc-biaed endcaps, a field would be pro- duced, which would achieve axial confine- ment of the ions. One of the principal advantages of this configuration is that the electrodes would surround the trapped ions almost com- pletely, shielding them against fields ex- ternal to the trap electric fields. Other ad- vantages can be discerned by analysis of the trapping fields under the conventional assumptions that the trappin frequency greatly exceeds the characteristic frequen- cies of the secular motions of the ions and that the micromotions at the field frequen- cy are small in comparison with the range of secular motions. If it is also assumed that the cloud of trapped ions is not dense enough to affect the electrostatic poten- tial in the trap significantly, then one can compute all radio-frequency and dc elec- trostatic fields in the trap by solving Lap- lace's equation with the applied potentials as boundary conditions. Conventional trapping-field theory yields an effective steady component of poten- tial (as a function of position) that repre- sents the time-average effect of the radio- frequency field upon the ions. Then, the dc bias potential (as a function of position) is added to obtain the total effective poten- tial field that governs the secular motions of the ions. Such calculations have been performed for a typical 199Hg + trap (radius 9.5 mm, length 108 mm, radio-frequency potentials ± 100 V) under several different dc bias conditions. The calculations lead to the following conclusions, among others: • The electric field on the electrode surface would have a minimum in the center of each cylindrical-sector electrode. Conse- quently, it should be possible to cut small viewing holes there without Significantly disturbing the electric fields inside the trap. • Near the ends of the trap, that compo- nent of the effective potential that arises from the radio-frequency field would tend to expel any ion from the trap, regardless of its charge. • If dc biases were applied to the cylindri- cal-sector electrodes, the resulting static electric fields near the ends of the trap would tend either to expel ions from the trap or to localize them near the center of the trap, depending on the polarities of the biases. In addition, the combined effect of the radio-frequency and dc bias fields would be to create a new equilib- rium poSition for ions, with a new non- zero equilibrium potential. • As in all linear traps, the effective trap- ping volume available for the storage of ions would be greater than in conven- tional hyperbolic trap configurations. This work was done by Ruthann K. Melbourne, John D Prestage, and wtfollah Maleki of Caltech for NASA's Jet Propul· sion Laboratory. For further information, Circle 96 on the TSP Request Card. NPO-18335 Chamber for Microgravity Combustion Experiments A rugged unit can be used in a drop tower. Lyndon B. Johnson Space Center, Houston, Texas Specimen Copper Isothermal Reference Block Gas Inlet - Fast-Response Thermocouple Wire Ceramic Insulator @ @ @ Instrumentation Feedthrough Igniter-Terminal Feedthrough Elongated Viewing Port @ @ @ @ Hub Top 10.5 in. A Hub Top With Gas Ports encloses the combustion chamber. Instrumentation wire is fed into the chamber through its base. Combustion is initiated by a pyrotechnic wire fuse. Oxygen is supplied to the chamber to support combustion , then argon is fed to quench it. NASA Tech Briefs, September 1992 A versatile container for microgravity com- bustion experiments can be used in outer space, in an airplane, or on Earth in a drop tower. The container can withstand repeat- ed prolonged impacts. The container is a portable test appara- tus with a data-acquisition-and-control sys- tem. It incorporates a window for viewing combustion and feeds gases to the com- bustion chamber, including oxygen fOT combustion and argon and nitrogen for quenching. A rod specimen is mounted securely from the top of a copper liner in the com- bustion chamber (see figure). Electrical wires at the bottom of the specimen ignite it on command from the control system. Wiring for instrumentation and control en- ters the combustion chamber through its base. The pressure in the chamber can be as high as 1,440 Ib/in.2 (10 MPa). At the high- pressure limit, a burst-disk valve releases the gases from the chamber. The entire combustion and quenching sequence can be viewed or filmed through an elongated window measuring 2 by 6 in. (5 by 15 cm). This work was done by Theodore A. Steinberg of Lockheed Engineering and Sciences Co. for Johnson Space Center. For further information, Circle 81 on the TSP Request Card. MSC-21777 65 Measuring Spatially Varying Transmittance of a Filter A focusing!collimating-and-scanning apparatus fits in the sample chamber of a spectrophotometer. NASA's Jet Propulsion Laboratory, Pasadena, California A focusing/collimating-and-scanning apparatus adapts a commercial spectro- photometer to the spectral transmittance of an optical filter as a function of position on the filter, at a spatial resolution as small as 25 p,m. The apparatus is mounted in the sample chamber of the spectrophotometer. Quasi·Colllmated Broa.dband Light From Source .. .. '"'-"* T ........... .... ~ ~ Collimated OUtput Beam to Spectrophotometer The FocusinglColli- mating-and-Scan- ning Apparatus en- ables a spectropho- tometerto measaure the spectral transmit- tance at many differ- ent positions on the filter. Because the apparatus includes only re- flective optics, measurements can be made in any wavelength band covered by the spectrophotometer: infrared, visible, or ultra- violet. The apparatus was used originally to measure the spatially varying spectral transmittance of a nominally linearly var- ing optical filter that had been fabricated for a thermal-infrared imaging spectrometer. .. AII'Refiecl iv~ / Microscope Objective / :"~ ~:e AII'R.flectiV. Mounted on Microscope Lens Translation Stage Objective Lens In the usual operation of the spectro- photometer used to test the filter, a col- limated beam of light that has a relatively large cross section passes through the specimen in the sample chamber and on into a scanning monochromator and de- tector for analysis. However, to measure the spatial variation of the spectral trans- mittance of a filter, it is necessary to focus the light to a small spot on the filter. Ac- cordingly, in the focusing/collimating-and- scanning apparatus, two all-reflective mi- croscope objectives are used (see figure). The first objective focuses the quasi-col- limated light from a source onto the de- sired spot. To achieve maximal resolution, one of the axes of a three-axis translation stage on which the filter is mounted pro- vides a focus adjustment to place the plane of the filter precisely at the focal point of the first microscope objective. The second microscope objective recollimates the diverging cone of light that emerges from the filter. Thus, the beam that enters the monochromator is collimated, just as in the unmodified spectrophotometer, but the transmittance measured is that of the focal spot on the filter. CUSTOM ENCLOSURES DESIGN AND FABRICATION ASSEMBLED FROM STANDARD COMPONENTS • Pre engineered construction system produces rigid frameworks using aluminum extrusions and die cast corners. • Complex enclosure shapes are achieved with over 50 different stock angled extrusions and matching castings. • Square and radius profiles in 1wo sizes. • A wide selection of additional hardware. • Stock components for in-house assembly. • Pre-cut kit assemblies. • Complete design and fabrication. CRYSTAL MARK, INC. Custom Enclosure Division NO WELDING MITERING FORMING The other two axes of the translation stage position the filter laterally with re- spect to the axis of the beam of light. By making measurements at a uniformly or otherwise suitably spaced lattice of points, one can measure the dependence of spec- tral transmittance upon position on the fil- ter. The mechanisms of the translation stage are spring-loaded, and the adjustments along each axis are all made in the same sense each time to preclude backlash . This work was done by Clayton C. LaBaw of Caltech for NASA's Jet Propul· sion Laboratory. For further information, Circle 25 on the TSP Request Card. NPO-18298 Consoles Racks Test Benches Machine Guarding Pre-cut Kit Assemblies Electro-mechanical Enclosures 1062 Fairview Drive, Carson City, NV 89701 TOLL FREE 1-800-788-7521 . FAX 702-885-2774 66 For More Information Circle No. 536 NASA Tech Briefs, September 1992 NEW FROM INCO SPP. .. EXTRA FINE NICKEL POWDER -- Inco Type 210 Nickel Powder JUST ADD YOUR IMAGINATION SEND FOR YOUR FREE SAMPLE TODAY INca spp Park 80 West-Plaza Two , Saddle Brook, NJ 07662 Shin-Muromachl Building , 4-3 Nihonbashi-Muromachi 2-Chome, Chuo-ku, Tokyo 103 Japan 1-3 Grosvenor Place , London SW1X7EA England 15/FI Wilson House, 19-27 Wyndham Street Central , Hong Kong For More Information Circle No. 652 Classification of Land Cover From Airborne MSS Data Refinements of the basic classification method increase accuracy. Ames Research Center, Moffett Field, California A method for the processing of images of rural uplands produced by an airborne multispectral scanner (MSS) semiautomat· ically classifies designated areas within each image into types of land cover (e.g ., grass, woods, and buildings). The method is based on principles similar to those of other spectral·image-classification meth- ods in that it involves the selection of wave- length bands, radiometric calibration, cor- rection for the effects of the scan angle (away from nadir) and the atmosphere, training, and assessment of accuracy. In this case, the images of each scanned area are produced simultaneously in four wavelength bands: 0.45 to 0.52 pm (green), 0.63 to 0.69 p.m (red), 0.76 to 1.05 pm (near infrared), and 2.08 to 2.35 p.m (middle in- frared). These bands were selected be- cause they are related to the biophysical characteristics of vegetation. To identify a set of training data, random numbers are used to select fields from lists of fields that are known, from previous surveys, to have land cover of the types to be studied. These data are used to train a maximum- likelihood classification algorithm. The basic version of the method involves classification of each picture element ac- cording to its spectrum. The basic method can be augmented with one or more of the following five refinements: 1. Per-field sampling, in which the samp- ling unit is a field rather than a picture element or group of picture elements within a field (a "field" could also be, say, part of a forest). The main benefits are reduced classification time and the elimination of mixed classes within fields. The main disadvantage is the need to define the boundaries of each field prior to analysis. 2. Low-pass filtering, in which the radiance of each picture element is replaced by an average over that and the neigh- boring picture elements. It has been found that low-pass filtering may increase the accuracy of classification for land covers, the images of which have high spatial frequencies. Basic Per-Picture- Element-Sampling Version D Mean Classification Accuracy, Percent REFINEMENTS .~ - II) e tOQ) co U Q)Q; £Cl. 0"2 - 0 .~ "§ -Q) to> 0;0 eo. .~ ~a. to E ~ to ~U? ~g P = Prior Probabili t ies F = Low-Pass Filtering T = Texture o = Imagery From Two Dates P-F = Per-Field Sampling e E gl ~ 30 --------- --- - ---- --- ::!!Uf e ~ .- :l ~:§ tOCl. ~ ~ 40 --------------------- eCl. The Mean Classification Accuracies were computed for 16 different versions of the classification scheme. 3. Image texture, which, the radiance of each picture element is replaced by the standard deviations of that and the neighboring picture elements. The main advantage is the ability to separate spa- tially " rough" surfaces (e.g. , forest) from spatially "smooth" surfaces (e.g., glass). 4. Prior probabilities: The proportions of types of land cover derived from prior studies are used to weight the maximum- likelihood classification algorithm. The types of land cover that occupy the largest areas have the largest weights and tend to be classified most accurately. 5. Imagery from Mo dates: Data from two dates (e.g., one in June and one in Sep- tember) yield a small increase in accura- cy of classification. The basic method with various comb i- nations of refinements was applied to air- borne airborne MSS data on eight types of land cover in upland England. The figure shows the mean accuracy of classifica- tion for each version of the method. The highest mean accuracy, 79 percent, was obtained by use of all refinements ex- cept low-pass filtering. The per-field-samp- ling refinement produced the largest single increase. This work was done by Paul J. Curran and Mike I. Pedley of the University of Sheffield while Paul J. Curran was an NRC Senior Research Associate at Ames Re· search Center. For further information, Circle 10 on the TSP Request Card. ARC-12688 Adjusting Curvatures of Large Mirrors and Lenses Actuators apply stresses to generate compensatory distortions. NASA's Jet Propulsion Laboratory, Pasadena, California In a technique for adjusting the curva- ture of a large focusing mirror or lens, ac- tuators apply stresses to generate distor- tions that counteract undesired distortions. The technique is particularly applicable to large astronomical-telescope mirrors with 68 diameters of the order of 60 cm or more. The distortions to be counteracted are typically of the order of a few microns or less; they are caused by changes in tem- perature and changes in orientation in the gravitational field. In the case of mirrors fabricated on Earth but operated in outer space, distortions are caused by removal of the gravitational field . In addition, opti- cal performance is affected by variations in the index of refraction of air with tem- perature and altitude. Although all of these NASA Tech Briefs, September 1992 Thr.ad~ShI-_aft _____ ---1 A Telescope Frame SECTION A-A Motor-and-Gear Assemblies under remote control vary the squeeze of a ring clamp and the push or pull of a hollow shaft to make fine adjustments in the curvature of a telescope mirror. effects and more are taken into account in the design and fabrication of large mirrors and lenses, it is still necessary to apply compensatory distortions as fine adjustments to real - ize the full potential of these optics to provide subarcsecond resolutions. In the version of the technique illustrated in the figure , compensatory distortions are applied by (1) a peripheral ring clamp or several clamps that are tightened or loosened by motor-and-gear drives and (2) an inner concentric threaded hollow shaft driven by another motor-and-gear assembly. Tightening or loosening the clamps affect the curvature of the mirror mostly in the outer concentric zones, while the axial force exerted by the hollow shaft affects the curvature mostly in the inner concentric zones. In another version (not shown in the figure) , many actuators could be mounted on a backing plate behind the mirror to apply a compensatory distortion indepen- dently to each of many zones. In either version , the motor-and- gear assemblies or other actuators can be adjusted remotely. To formulate an optimum design , one must consider the actuators and mounts to be an integral part of the mirror or lens system . The mirror or lens can be made more adjust- able by making it thinner. Although this makes the mirror or lens more vulnerable to some distortions, it is not necessar- ily a serious disadvantage: one could also design the optical figure to have a small initial distortion that can be eliminated by tightening a ring clamp to some nominal small tension . This work was done by Morris M. Birnbaum of Caltech for NASA's Jet Propulsion Laboratory. For further information, Circle 47 on the TSP Request Card. NPO-18345 NASA Tech Briefs, September 1992 Above and Beyond the Call of Duty Eigiloy® When you need high performance. • Resists Stress & Cracking • Corrosion Resistant • Non-Magnetic • Long Fatigue Life • Performs Consistently in Temperatures Ranging From -3000 to 8500 F Over 40 Alloys in Strip AND Eigilo~ Limited Partnership .................... 1565 Fleetwood Drive ~ ,1' ;:.JIll""" Elgin, IL 60123 .. Tel: (708) 695-1900 Wire Fax: (708) 695-0169 Pratt & Whitney and GE Approved For More Information Circle No. 312 TAKE A CLOSER LOOK • • AND SEE WHY SOUTH CAROLINA RANKS As O NE OF THE N ATION'S T op T EN L OCATIONS FOR MA UFACTURING. For a free Prospectus contact: Palmetto Economic Development Corporation Represeneing Cenrral Elecrric Power Cooperative and Saneee Cooper 1201 Main Sereer, Suire 1710 • Columbia, SC 29201-3213 Phone' (803) 254-9211 • FAX (803)771-0233 For More Information Circle No. 525 69 70 Visible Laser Diode Modules Complete system includes: o SM Laser Diode o Power Supply o Optics $200/single piece Features: o 1/2 x 2 inches o Circuit Protection o Fine Focus (60 tpi) o Adjustable Optical Output Power Power Technology Incorporated 7925 Mabelvale CutoH, Mabelvale, AR 721 03 (501) 568-1995 Fax (501 ) 568-1994 For More Information Circle No. 532 Questions about Pressure Control? Talk to the problem solvers for a wide range of pressure regulators and valves-for gas and liquid control from subatmospheric to 15,000 PSIG! Over 50 standard models + options Choices include materials, pressure ranges, port types and flow capacties (Cv =,01 to 15), Pressure redudng, back pressure, dome loaded, two-stage and electronically controlled styles do the job in high purity, hydraulic, high pressure, vacuum and vaporizing applications, C:::=::::::;--;:::::::::;:::::::J. ' 12616 Industrial Blvd, UESCOM Elk River, MN 55330 COR PO RAT' 0 N Tel. (612) 441-6330 For More Information Circle No. 628 Towed Articulated Housing for Geophysical Measurements A snakel ike string of enclosures carries instruments over a var iety of surfaces, NASA 's Jet Propulsion Laboratory, Pasadena, California A snakelike articulated string of rigid shells carries scien- tific instruments over land and sea surfaces , The "snake " can be towed by a helicopter, boat, kite , balloon , or any other suitable veh icle so that it traverses the underlying surfaces and acquires scientific data about the local environment. The shells are smooth , truncated cones, one nested within another (see figure). Each cone is connected to an internal chain by a bolt in a recess that is covered by the preceding cone . The shell thus presents a smooth , free- sliding surface. The string of shells articu lates readily to negotiate obstacles but is locally stiff to be able to lie across a narrow crevasse. In a demonstration , a prototype of the "snake " was towed across the Mojave desert by a balloon filled with helium. In other demonstrat ions, nautical vers ions of the snake were towed by power boats and kites across the surfaces of Puddingstone Lake and Los Angeles harbor. A snake could be used , for example , to map the properties of seawater along trade-wind routes or to gather weather data while traversing polar ice . This work was done by James D. Burke of Caltech and James Cantrell of Utah State University for NASA's Jet Propulsion Laboratory , For further information, Circle 9 on the TSP Request Card. NPO-1 7656 Cones Typica l ly Made of Aluminum '~rYP~,czal )~~~~~~fr---~~14~i n~' ~zY~P,czal~) ~JI Chain 6-ln. Dlameler ~yplcal) k~~~~~ The Instrument Snake consists of overlapping cones of aluminum strung on an internal chain. In addition to housing scientific instru- ments, the snake serves as ballast for the kite or balloon that tows it. NASA Tech Briefs, September 1992 Chamber for Testing Infrared Imaging Detectors The chamber encloses the cold, vacuum, low-background-radiation environment needed for testing. NASA's Jet Propulsion Laboratory, Pasadena, California The apparatus shown in the figure is a chamber designed specifically for testing and calibrat ion of planar arrays of long- wavelength infrared photodetectors. The chamber provides the cold, vacuum, low- background-radiation environment and the optical and electrical feedthroughs need- ed to test these highly sensitive detectors, which are essential to advanced remote- sensing instruments. Detectors can be test- ed in this chamber at temperatures rang- ing from about 300 K (ambient) down to about 4.2 K (liquid helium). The chamber is equipped with multiple ports for vacuum pumps, vacuum gauges, cryogenic fluids, sources of radiation , and camera heads. A radiation shield in the chamber encloses an optical table;. the table has an internal serpentine passage, and a tube is wound in a spiral around the outer surface for cooling by liquid nitrogen. The detector arrays to be tested are mounted in the camera heads. The stand- ard camera heads used with the chamber are commercial miniature vacuum test chambers that also provide the requisite fluid , optical , and electrical connections , are equipped with intemal radiation shields, and can be cooled by liquid helium, nitro- gen, or neon. These camera heads are known as 100-pin Dewars because each includes 100 triaxial 50-0 terminals to con- nect the outputs of the sensors to the ex- ternal test circuits. Because infrared-transmissive optics and infrared-reflective optics that have ac- ceptably wide passbands and acceptably low losses are difficu lt to fabricate, the pin- hole-camera method is used to form the images on the detectors. A small plate containing a pinhole is mounted on an end cap that is bolted to the lid of the internal radiation shield in a 100-pin Dewar. Pinhole plates can be interchanged to install pin- holes of different sizes as needed. In preliminary tests, the chamber was Ports for Camera Heads and/or Sources o f Radiati on Interface to ----~"'tl Vacuum Pum p Opt ical Table Camera Head (1 OO·Pi n Dewar) TOP VIEW WITH COVER REMOVED 18 in. ---/0- -,\ I I , , \ " I I " ., , Fiberglass Spacer 1-- --24 in .------ Array of Detectors Under Test in Contact With End of Cold Pedestal SI DE VIEW Th is Vacuum! Cryogenic Test Chamber accommodates a variety of infrared sources, detectors, and associated equipment for testing of the detectors at temperatures down to about 4.2 K in a low-background-radiation environment. found to consume about 6 liters of liquid nitrogen per hour during initial cooldown (which typically required about an hour). Thereafter, the chamber consumed about 2 liters per hour in maintaining the detec- tors at 77 K. Although the preliminary mea- surements of the vacuum were not com- plete, it appears that the pressure in the chamber falls to about 10 - 4 mtorr (about 10 - 5 Pal after pumpinq for a few hours. This work was done by Craig 0. Staller and Richard W Capps of Caltech and Douglas Butler, Nancy Moss, and Wynn Norwood of R. G. Hansen and Associates for NASA's Jet Propulsion Laboratory. For further information, Circle 92 on the TSP Request Card. NPO-18089 Variable~emperature Cryostat for Radiation- ~J Damage Testing of Germanium Detectors Operating and annealing temperatures can be varied over wide ranges without breaking vacuum. Goddard Space Flight Center, Greenbelt, Maryland Variable-temperature cryostats were de- veloped and used in a study of radiation damage to, and annealing of, germanium gamma-ray detectors. The cryostat design comes in two styles: one that accommo- dates a large (140-cm3) single detector and one that accommodates two medium- sized (90-cm3) detectors. Each two-detec- NASA Tech Briefs, September 1992 tor unit in the study contained a p-type and an n-type detector. The resolution of germanium detectors degrades when the detectors are exposed to the radiation environment of outer space. P-type degrctors degrade faster than n-type detectors, and the rates of degradation of both types are related to the operating tem- perature. Most of this knowledge comes from testing small planar detectors. In past studies, the refurbishment of a detector for the next test has involved removal of the detector from its cryostat and annealing at temperatu res from 125 to 150°C. Germainum detectors will be the heart of many gamma-ray-spectrometer instruments 71 on future NASA missions. Gamma-ray spec- troscopy will certainly be important for mis- sions to asteroids, comets, Mercury, and the Moon. All of these missions are longer than the useful life of a new detector. There- fore, radiation-Osed thermally conductive fluid would be used to thermally couple a tem- perature probe to a dry well. The objective is to monitor the temperature of hypergolic fluids (nitrogen tetroxide and hydrazine or unsymmetrical dimethyl hydrazine) that flow in pipes with a dry well. Because the heat-transfer fluid would not react chemi- cally with either hypergol, a leak that re- sults in contact with either hypergol would NASA Tech Briefs, September 1992 not pose a hazard. Although compatibility with hypergolic fuels is normally a consid- eration only in rocket engines, there may be terrestrial applications in some organic- chemical synthesis processes. The fluid would be more precisely de- scribable as a slurry or composite of liquid and solid parts. It would consist of a per- fluoroalkylether matrix (the vehicle fluid) containing suspended particles of copper oxides or other metallic oxides that do not react with the hypergols. Such a compos- ite fluid would have a thermal conductivity greater than that of organic derivatives of petroleum. This work was done by Gary W Kurtz of Lockheed Space Operations Co. for Ken- nedy Space Center. No further documen- tation is available. KSC-11389 77 Books and Reports These reports, studies, handbooks are avail- able from NASA as Technical Support Pack- ages (TSP's) when a Request Card number is cited, otherwise they are available from the National Technical Information Service Biaxially Stretched Polycarbonate Film for Capacitors Electrical properties at high temperatures are improved, A report describes experiments on the effects of biaxial stretching on the crystal structures, dielectric properties, and se- lected thermal and mechanical properties of biaxially stretched polycarbonate films. This study was motivated by the need to improve the polycarbonate dielectric films used in capacitors, which have been found to be unreliable at high temperatures, especially in low-voltage, high-impedance applications. A stretched film is said to be "oriented" in the sense that the stretching alters its crystal structure and properties in a man- ner related to the direction of stretch. The polycarbonate films now used in capaci- tors are cast from solution, then stretched along one direction (uniaxially oriented). To make biaxially oriented specimens for this study, polycarbonate films were first cast from solution, then heated to a tempera- ture of about 170°C and stretched in one direction to 2.27 times their original lengths followed by stretching in the perpendicular direction to various degrees (some to 2.0, some to 3.0, and some to 3.7 times their original lengths). Uniaxially and biaxially oriented film specimens were analyzed by differential scanning calorimetry and x-ray diffraction to determine the types and degrees of crystallinity in them. Other specimens were subjected to tests of their dielectric properties, including (1) electrical break- down strength, (2) insulation resistance vs. time at a temperature of 100 °C, (3) dissi- pation factor (at a frequency of 1 kHz and temperature of 25°C) after exposure to a temperature of 100°C for various times, and (4) coefficient of variation of capaci- tance with temperature (a measure of the dimensional stability of the film) after ex- posure to 100 °C for 1,000 hours. The results of the tests show that biax- ial stretching at the highest stretch ratios (2.27 and 3.7) produces the highest degree of crystallinity (about 37 percent), with a Single crystalline phase and a distribution of crystallites more nearly isotropiC than is that of uniaxially oriented film. The in- creased crystallinity, in turn, is correlated with greater breakdown voltage. This is con- sistent with the premise, stated in a pre- vious study, that the boundaries of crystal- lites are sites of electrical weakness. The life tests at 100 °C showed no signi- ficant degradation. Indeed, insulation resis- tances increased, possibly because of de- sorption of contaminants that had entered during fabrication . The dissipation factors remained constant, and the dimensional stabilities remained high. This work was done by Shaio-Ping S. Yen, Lynn E. LDwry, and Clyde P. Bankston of Caltech for NASA's Jet Propulsion Laboratory. To obtain a CO{Yf of the report, "Morphology and Dielectric Properties of Biaxially Oriented Polycarbonate Films for Capacitors," Circle 36 on the TSP Request Card. In accordance with Public Law 96-517, the contractor has elected to retain title to this invention. Inquiries concerning rights for its commercial use should be ad- dressed to Edward Ansell Director of Patents and Licensing Mail Stop 305-6 California Institute of Technology 1201 East California Boulevard Pasadena, CA 91125 Refer to NPO-18090, volume and number of this NASA Tech Briefs issue, and the page number. ANNOUNCING: A TOUGH FORMABLE INSULATION THAT CAN GO TO HELL ... PYROPEL 111 : a new concept in structural insulation. Pyropel is a new lightweight, high tempera- ture, non-woven insulation material that can be used in flat sheets or formed into a variety of shapes. It is 100% polyimide and contains no resinous binders. This, combined with its fibrous, three-dimensionally reinforced construction, gives Pyropel significant design, performance and assembly advantages over more conventional insulation materials. -300°F to +600°F. The use of polyimide permits extended performance at cryogenic temperatures as low as -300·F, and continuous use in applica- tions that reach temperatures as high as +600·F (and short-term exposure up to +800·F without losing thermal or dimensional stability). Pyropel does not melt, drip or sup- port combustion. It has a low heat release and emits almost no smoke. Rigid, lightweight, resists damage. Pyropel's three-dimensionally reinforced struc- ture provides exceptional rigidity and strength. It is extremely lightweight, with densities as low as 12 Ibs/ff and in thicknesses from 0.063 78 to 0.38 inches. Pyropel makes an excellent core material where thermal insulation and/or acoustic dampening are required. It can be bonded easily with thermoplastic adhesives and is chemically inert to acids and solvents. Reduce assembly and maintenance costs. Pyropel is available in flat sheets or custom shapes tailored to your requ irements. It can be formed into self-supporting covers, lids, housings, sidewalls and ducts---combining features that save assembly time and expense. Free test samples. Prove to yourself how well Pyropel performs under fire. Write or call today for your free literature and product sample. ..II I~ INTERNATIONAL A L International L.P. 777 West Street Mansfield, MA 02048-9114 Tel (508) 339-7300 FAX (508) 337-8550 For M ore Informat ion Circle No. 441 NASA Tech Briefs, September 1992 HOVIMET CONDUCTIVE PIGMENTS Conductive Silver Coated Nickel Flakes Conductive Nickel Flakes Conductive Silver Coated Nickel Spheres Conductive Nickel Spheres Conductive Nickel Coated Alumina Nickel Coaieu Graphite Also: Conductive Nickel Coated Glass Frit Conductive Nickel Coated Aluminum Conductive Nickel Pigment 525 Conductive Silver (0.5%) Stabilized Nickel Flakes And Custom Nickel Coating Custom Micron Separation of Nickel Powders Custom Screening of all Novamet Pigments ! NOVAMET! Novamet Specialty Products Corporation, An IN CO Company 10 Lawllns Park, Wyckoff, New Jersey 07481 . (201 ) 891-7976 For More Information Circle No. 635 FL U KE A THE T&M Introducing ScopeMeter™ Now there's only one to reach for. Imagine what you can do with a hand-held instru- ment that com- bines a 50 MHz, 25 megasamples per second, dual-chan- nel digital storage oscilloscope with a feature-packed 3000-count digital multimeter, all in a rugged, sealed industrial package with battClry operation that you can take anywhere you go. For the name of your local Fluke distributor call 1-800-87-FLUKE. C Copyright 1992, John Fluke Mfg. Co .. Inc. P.O. Box 9090, Everett WA 98206 Ad No. 00197 FLUKE ® REAL-TIME AVTS FOR MISSILE SEEKERS & FIRE CONTROl. PROPRIETARY ALGORITHMS TRACK TARGETS IN CLUTIER. OUTPERFORM EDGE, CENTROID, CORRELATION TRACKING TECHNIQUES. ULTRA MINIATURE AND VME VERSIONS AVAILABLE. ISCAN " 125 CAMBRIDGEPARK DRIVE CAMBRIDGE. MA 02140 TEL: 617·868·5353 FAX: 617·868·9231 ~: ~ Computer Programs COSMIC: Transferring NASA Software COSMIC, NASA's Computer Software Man- agement and Information Center, distributes soft- ware developed with NASA funding to Industry, other govemment agencies and academia. COSMIC's inventory is updated regularly; new programs are reported In Tech Briefs. For additional Information on any of the programs descnbed here, circle the appropriate TSP number. If you don't find a program In this Issue that meets your needs, call COSMIC directly for a free Computer Programs These programs may be obtained at a very reasonable cost from COSMIC, a facility sponsored by NASA to make computer pro- grams available to the public. For informa- tion on program price, size, and availability, circle the reference number on the TSP Request Card in this issue. Physical Sciences Software for Processing Meteorological Data Data can be interpolated, plotted, and otherwise generally processed into meteorologically useful forms, GEMPAK is a package of general mete- orological software developed at NASN Goddard Space Flight Center. It includes programs to analyze and display surface, upper-air, or gridded data, including the outputs of mathematical models. There are very general programs to list, edit, and plot data on maps, to display profiles and time series, and to draw contours, stream- lines, and cross sections in the case of gridded data. In addition, there are Barnes objective analysis programs to grid the data on surface and upper ai r. The programs include the capabilities to derive meteorological parameters from those found in the set of data, to perform vertical interpolations to different coordi- nate systems, and to compute an exten- sive set of gridded diagnostic quantities by specifying various nested combinations of scalar and vector arithmetic, algebraic, and differential operators. A graphicsltrans- formation software subsystem, GEMPLT, provides device-independent graphics and the capability to display output in a varie- ty of map projections or overlaid on satel- lite imagery. GEMPAK is written in FORTRAN 77 and has been implemented on VAX computers under VMS. A UNIX version, which has been verified on a SUNSparc workstation using SUNOS and on a Silicon Graphics review of programs In your area of interest. You can also purchase the annual COSMIC Software Cata- log, containing deSCriptions and ordering Informa- tion for available software COSMIC IS part of NASA's Technology Transfer Network. COSMIC - John A Gibson, Director, Phone (706) 542-3265 , FAX (706) 542-4807 The UniverSity of Georgia. 382 East Broad Street, Athens, Georgia 30602 computer using IRIX, is also available. The VMS version is delivered with the object code for the Transportable Applications Executive (TAE) program, which serves as the user interface, An alternate, built-in interface can be used with either the VMS or UNIX versions. To use the TAE (classic) with the UNIX version, a separate license for TAE PLUS must be obtained. This program was developed in 1985. The current version, GEMPAK 5.0, was re- leased in 1990. The package of software is delivered with source code. An exten- sive collection of subroutine libraries en- ables users to format data for use by GEM- PAK, to develop new programs, and to enhance existing ones. GEMPAK is available by license for a period of 10 years to approved licensees. The licensed program product includes the GEMPAK source code, sample data, and one set of supporting documentation. Ad- ditional documentation may be purchased separately. VAX and VMS are trademarks of Digital Equipment Corp. UNIX is a trademark of AT&T Bell Laboratories. This program was written by Mary L. desJardins of Goddard Space Flight Center. For further information, Circle 73 on the TSP Request Card. GSC-13402 Reformatting Data From X·Ray Photoelectron Spectroscopy Columns of numbers in ASCII format are converted to DEC binary format. It is otten desirable to use a central, more powerful computer to analyze data cap- tured on a local computer. ASCI TOVG, a program for use on an IBM PC-series com- puter, creates files in binary format from columns of numbers in American National Standard Code for Information Interchange (ASCII) format. The resultant files are suit- able for interactive analysis on a DEC PDP-11!73 computer under the Micro-RSX operating system running the VGS-5000 Enhanced Data Processing (EDP) software 80 For More Information Ci rc le No. 447 NASA Tech Briefs, September 1992 package. EDP analyzes the data interactive- ly with a color graphics display, speeding up the analysis considerably when com- pared with batch job processing. Its interac- tive analysis capabilities also enable the researcher to watch for spurious data that might go undetected when some form of automatic spectrum processing is used. The incompatibility between the floating- point representations of numbers of an IBM PC and a DEC computer were resolved by a FORTRAN subroutine that correctly con- verts single-precision, floating-point num- bers on the PC so that they can be read directly by such DEC computers as aVIV<. The subroutine also can convert binary DEC files (single-precision, floating-point numbers) to IBM PC format. This may prove a more efficient method of moving data from, for instance, a VIV<-ciuster down to a local IBM PC for further examination, ma- nipulation, or display. The input data file used by ASCITOVG is simply a text file in the form of a column of ASCII numbers, with each value followed by a carriage return. These can be the out- put of a data-collection routine or can even be keyed in through the use of a program editor. The data-file header required by the EDP programs for an x-ray photoelectron spectrum is also written to the file. The spectrum parameters, entered by the user when the program is run, are coded into the header format used internally by all of the VGS-5000-series EDP packages. Any file-transfer protocol that provides for binary data can be used to transmit the resulting file from the PC to the DEC computer. Each EDP data file includes at least a four-block information section ahead of the data. The header information is needed be- cause data files from a number of different experimental techniques, as well as multi- region and depth-profile data, can be ana- lyzed with the EDP software. This informa- tion includes general information about the data file, names of spectral regions, de- scriptive comments, information about the experimental technique, and information about such experimental conditions as the type of scan, the range of the scan, the source of excitation, and the analyzer mode. The files produced by ASCllDVG are in the form of a single-spectral-region, bind- ing-energy-scan, x-ray photoelectron spec- trum. Comments included in the source code should facilitate expansion of the pro- gram to some other types of data files. This FORTRAN program was imple- mented on an IBM PC XT with the MS-DOS 3.1 operating system. It has a memory re- quirement of 53K bytes and was developed in 1989. This program was written by P B. Abel of lewis Research Center. For further in- formation, Circle 52 on the TSP Request card. LEW-14993 e e ber 1992 I I Fabrication Technology Operating System for Numerically Controlled Milling Machine The user can program machining operations quickly and easily. The OPMILL computer program is an operating system for a Kearney and Trecker milling machine. It provides a fast and easy way to program the manufacture of machine parts by use of an IBM-com- patible personal computer. The program gives the machinist an "equation plotter" feature, which plots any set of equations that define movements along axes (up to three axes simultaneously) and converts those equations to a milling-machine-con- trolling program that moves a cutter along a defined path. Other functions supported by OPMILL include the following: drill with peck, bolt circle, tap, mill arc, quarter circle, circle, circle 2 pass, frame, frame 2 pass, rotary frame, pocket, loop and repeat, and copy ARE YOU SPENDING TOO MUCH TIME DRAWING FLOWCHARTS? YOU NEED FLOW CHARTING TM 3. Every day, professionals worldwide save time and money using Flow .Charting 3. It's fast, efficient, easy to use, and alway produces presentation-perfect chart and diagrams. With Flow Charting 3' built-in flexibility, you can create customized charts u ing a variety of hapes, lines, and text- placed where you want them_ Plus, Flow Charting 3 is now available in a LAN version. Making it easy to hare files and set up work group for specific projects. And it's backed with free technical support and a 90-day no-risk guarantee. So if you're pending too much time drawing charts, call for a free demo and ee for yourself what makes Flow Charting 3 the be t-selling flowcharting software_ u o See your dealer today! Or for a free interactive demo disk,call 1-800-525-0082, ext. 2909_ International : 408 -778-6557 , ext. 2909. PAl ION & PAl ION Soflware Corporal/on No\ t ll is a regislert!d lrudemurk of No\ eU, Inc. Excel/ence in chartino the f lolU of i(/eos! Patton & Patton Software Corp. 485 Cochrane Circle, Morgan Hill , CA 95037 For More Information Circle No. 499 blocks. The system includes tool-manager software that can handle up to 25 tools and automatically adjusts the program to account for the length of each tool. It displays all tool information and stops the milling machine at the appropriate time. the hard disk, save the program to the disk with comments, view directories, merge a program on the disk with one in memory, save a portion of a program in memory, and change directories. OPMILL was developed on an IBM PS/2 computer running DOS 3.3 with 1 MB of random-access memory. OPMILL was written for an IBM PC or compatible 8088 or 80286 computer connected via an RS-232 port to a Kearney and li'ecker Data Mill 700/C Control milling machine. It requires a "D:" drive (fixed-disk or vir- tual), a "browse" or "text display" utility, and an EGA or better display. Users who wish to modify and recompile the source Information for the program is entered via a series of menus and compiled to the Kearney and li'ecker format. The pro- gram can then be loaded into the mill- ing machine, the tool path graphically dis- played, and tool-change information or the program in Kearney and Trecker for- mat viewed. The program includes a com- plete file-handling utility that enables the user to load the program into memory from "'---...... Step Up to Algor More than 6.000 engineers In 50 states and over 60 countries have stepped up to Algor, the most advanced finite element analysis and design software money can buy. All FEA models on this page were designed. analyzed and visualized on a PC with Algor software. The largest contains more than 24,000 nodes and 13,000 elements. Other Algor analysis packages Include buckling, nonlinear gap/cable, specialized vibration, composite elements, kinematics/dynamics, piping and more. L....--= ______ ~ __ Algor, a PC and You .. _The Total DesigniEngineering Team Algor. the world's leading design/analysis software for PCs. is specifically designed to fully exploit their increasing level of power. Tight bridges to CAD/CAM and other software create a seamless fit into your environment. Algor design software provides parametric design and results visualization tools (see actual screen photographs on this page) that are worthy of your expertise and creativity. And the engineering is built In. Typical Algor Engineering Software Packages Price Linear Stress Analysis with VlziCad Plus $1500 Stress, Vibration and Mode Shape Analysis with ViziCad Plus $2100 C Fluid Flow Analysis with ViziCad Plus $1100 D Heat Transfer Analysis with ViziCad Plus $1600 E Accupak--3-D Nonlinear Stress & Vibration $2500 Iconnex V EAGLE, Concurrent Engineering & Design Optimization $2300 Electrostatic Analysis with ViziCad Plus $1600 Interactive Demonstrationrrutorials - $19 to $49 luid Flow ree 36-Page Product Guide Notes: 3861486 Prices, shown in U.S. $, Your current PC has more computing • RLGDR. may change at any time. 3861486 power than your last one. Your next software uses extended memory. Weltek I PC will have even more. Algor coprocessor and selected Unix workstation software is constantly updated to take 150 Beta Drive versions available. Algor software Is sub- advantage of the power of new PCs. Pittsburgh, PA 15238-2932 USA )ected to nuclear power Industry Ib,=~;.;,;;;;;;;;g~..;;.;,;~.;,;;;;,~;,;;;,;;~~ 412-967-2700 Fax: 412-967-2781 Quality Assurance standards. In California: 714-564-2541 GSA Contract. GS 00 K 89 AGS 6270 PSOI 82 For More Information Circle No. 449 code will also need Turbo BASIC, Turbo C, and Crescent Software's QuickPak for Turbo BASIC. IBM PC and IBM PS/2 are registered trademarks of International Business Machines. Turbo BASIC and Turbo Care trademarks of Borland International. This program was written by R. B. Ray of Goddard Space Flight Center. For fur- ther information, Circle 29 on the TSP Re- quest Card. GSC-13366 ~ Mathematics and ~ Information Sciences Software Graphical User Interface for Analysis of Images CAMTOOL provides an easy-to-use, mouse-driven interface. The CAMTOOL software package pro- vides a graphical user interface between a Sun Microsystems workstation and the Eikonix Model 1412 digitizing camera sys- tem (Ektron Applied Imaging, Bedford, MA). The Eikonix camera system can scan and digitize monochrome or color images, half- tones, reflectives (e.g., black and white pho- tographs), transmissives (e.g., negatives, x rays), rigid or flexible flat material, or three-dimensional objects. CAMTOOL facilitates use of the camera system through an easy-to-use, mouse- driven interface. Users can digitize images and select from three destinations: work- station display screen, magnetic-tape drive, or hard disk. These three options make im- age data portable to a wide range of de- vices and software for further processing and analysis, and for immediate viewing of the initial digitized product. The applica- tion program also enables users to modify parameters that affect the digitization proc- ess and to initiate such system support options as calibration of the camera. CAMTOOL is written in C language and has been implemented on Sun3 and Sun4 workstations running SunOS. This package runs under SunView on a color monitor. The program is available on a 0.25-in. (6.35-mm) streaming-magnetic-tape car- tridge in UNIX tar format. CAMTOOL re- quires 101K of main memory. This package was developed in 1990. Sun is a trademark of Sun Microsystems, Inc. Eikonix is a trademark of Ektron Ap- plied Imaging, Inc. This program was written by Desiree M. LEonard, Scott R. Nolf. and Elizabeth L. Avis of Computer Sciences Corp. and Kathryn Stacy of Langley Research Cen- ter. For further information, Circle 89 on the TSP Request Card. LAR-14371 NASA Tech Briefs , September 1992 Technology 2002 Exhibits: Your One-Stop Shopping Place For Innovative Ideas Here's a partial list of the more than 250 federal laboratories, universities, and high-tech companies who will be showcasing their latest inventions and products in the giant Technology 2002 exhibits hall : Advanced Technology & Research Corp. AECL Technologies Aerospatiale AGEMA Infrared Systems Air Force Materiel Command Allied-Signal Aerospace Co. Ambassador Marketing American Ceramic Society American Welding Society Ames Research Center Argonne National Laboratory Army Corp. Of Engineers Army Electronics Technology And Devices Lab Army Institute Of Environmental Medicine Army Research Laboratory Amtec Engineering Inc. Arthur D. Little Inc. Association Of American Railroads ASTM Astro-Med Inc. Aviation Week Group Bergen Cable Technologies BF Goodrich Aerospace Biophysics Research Foundation Biotronics Technologies Birch, Stewart, Kolasch, & Birch Boeing Company Brookhaven National Laboratory Caltech Supercomputer Cannon Communications Center For Aerospace Information CI Systems Inc. C. Itoh Technology Inc. Concurrent Technologies Corp. Control Systems Analysis Corning Inc. o COSMIC/University Of Georgia County Of Loudoun, Virginia CTA Inc. Cybernet Systems Inc. Daedalus Enterprises Inc. Datatape Inc. Defense Programs Technology Transfer Diamonex Inc. Digiray Corp. Digital Equipment Corporation Dual Inc. Edison Sensor Technology Center Electronic Imagery Inc. Evans & Sutherland Federal Highway Administration Federal Laboratory Consortium Fermi National Accelerator Lab Ferrofluidics Corp. FUR Systems Inc. Fluid Dynamics International General Pneumatics Corp. Goddard Space Flight Center Hemco Corp. High Technology Systems Inc. Idaho National Engineering Lab Impra Inc. Information i-!andling Services Inframetrics Inc. Infrared Information Analysis Center/ERIM INPEXIINTROMARK Institute Of Environmental Sciences Integrated Engineering Software Integrated Sensors Inc. International Computers And Telecommunications International Environmental Institute Ithaco Inc. Jet Propulsion Laboratory Johnson Space Center Kennedy Space Center Knowledge Express Data Systems Langley Research Center Lawrence Livermore National Lab Lewis Research Center Los Alamos National Lab Machida Inc. MacNeal Schwendler Corp. Marshall Space Flight Center Maryland Department Of Economic & Employment Development McClellan Air Force Base MCNC Center For Microelectronics MERP Enhanced Composites Mid-Atlantic Technology Applications Center Millitech Corporation Moltech Corporation Morgantown Energy Technology Center NASA NASA Centers For The Commercial Development Of Space NASA Regional Technology Transfer Centers NASA Scientific And Technical Information Program NASA Small Business Innovation Research Program NASA Tech Briefs National Institutes Of Health National Institute Of Standards And Technology National Renewable Energy Lab National Technology Transfer Center Naval Research Lab Naval Surface Warfare Center NERAC Inc. NOAA Satellite Applications Lab North Carolina State University Novespace NSI Technology Services Corp. Numerical Algorithms Group Nyma Inc. Oak Ridge National Laboratory Oklahoma Center For Design And Manufacturing Oneida Research Services Pacific Northwest Laboratory Photonic Systems Inc. Pittsburgh Energy Technology Center Precision Filters Inc. Princeton Plasma Physics Lab E Proto Manufacturing Ramtek Corporation Research Triangle Institute RGB Spectrum RG Hansen Ribbon Technology Sandia National Labs Satellite Data Systems Small Parts Inc. Sonic Perceptions Inc. Sonoscan Inc. Southwall Technologies Inc. Space Age Technology Products Inc. Space News Spire Corporation Statistical Sciences Inc. Stennis Space Center Stephens Analytical Inc. The Latest Robotics Inventions Strategic Defense Initiative Org. Office Of Technology Applications Technical Insights Inc. Technology Access Report Technology Transfer Business Technology Transfer Society Technology Utilization Foundation Techron, Div. Of Crown International Tennessee Technology Foundation Thiokol Corporation Tiodize Company Turbomixer Corp. United Technologies/USBI Corp. University Of Dayton Research Institute Urethane 2000 U.S. Air Force, Manufacturing Technology Directorate U.S. Army Belvoir Research, Development, & Engineering Center U.S. Bureau Of Mines U.S. Department Of Agriculture U.S. Department Of Energy/Conservation & Renewable Energy U.S. Department Of Cnergyffricdync U.S. Environmental Protection Agency U.S. Naval Academy Vector Aeromotive Corp. Vermont Research Corp. Walter, Reed AMC Wolfram Research Inc. TecllllOlogy So 1101 We Can 'I /.£vell Sh()w /I To You! • • • • • • • • • • • • • • • • Embargoed Until • • December 1992 • 1, • • • • • • • • • • • • • • • • • One Technology 2002 exhibitor (we promised we wouldn't reveal their name) will unveil a revolutionary new transportation technology at the show ... you '" have to see it to believe it! Technology 2002/NTI Program Novem r30 ';a'!'.~"!"!liiI Technology Transfer Week Opening Ceremonies & Reception Speaker: Governor William Donald Schaefer, State of Maryland (invited) The pre-show reception offers the chance to preview the exhibits and meet government and industry leaders in an informal atmosphere. Admission is free for Technology 2002 full regis- trants and exhibitors. ,D cemb r1 ,:" •• 1.8.1,1.", Conference Opening - Federal Technology Overview Keynote Address: Senator Barbara Mikulski, State of Maryland National Technology Initiative - Opening Remarks: Speakers at previous NT! opening sessions have included these dignitaries: Barbara Hackman Franklin, Secretary, U.S. Department of Commerce Daniel S. Goldin, Administrator, NASA John W. Lyons, Director, National Institute of Standards and Technology William K. Reilly, Administrator, U.S. Environmental Protection Agency James D. Watkins, Secretary, U.S. Department of Energy 10:00 - 11'00 am Plenary Theme Panels (Panelists to be announced) Expert panelists will explore three areas vital to the long-term health of U.S. businesses: Cooperative Research And Develop- ment; Investment And Financing; and Manufacturing Excellence. '11·1 •• I'Ft·,,' Government-Industry Dialogue Answers to your questions about the technology transfer process, partnering opportunities, and federal technology resources and contacts. F IB.!.M"!"!4iIi National Critical Technologies Concurrent Sessions Each presentation will last 30 minutes, including a question and answer period. Registrants may choose to attend whole sessions (four presentations) or individual presentations from a number of different sessions. Meeting rooms are situated in close proximity for easy and quick movement during sessions. Room assign- ments will be listed in the final program distributed at the show. Session A101 Material Part 1: Materials Processing INEL Spray Forming Research Kevin M. McHugh and James F. Kay, Senior Scientists, Idaho National Engineering Laboratory A novel spray forming teChnology produces near-net-shape solids and coatings of metals, polymers, composites, and other materials. Advantages: improved product quality and major cost savings. Film Fabrication Technologies Robert D. McConnell, Superconductivity Program Manager, National Renewable Energy Laboratory This presentation will spotlight an array of film fabrication techniques - including electron beam evaporation , ion beam sputtering, chemical vapor deposition, and melt coating - with commercial applications in fields ranging from superconductivity to photovoltaics. The Effect of Hydrogen on the Optical and Scratch-Resistant Properties of Diamondlike Carbon Films Michael T. Kussmaul, Research Engineer, Sverdrup Technology Inc.; Bruce A. Banks, Chief, Electro-Physics Branch, and Michael T. Mirtich, Engineer, Lewis Research Center Using an innovative dual ion beam system, Lewis researchers have created extremely hard and clear thin films with applications in the military, ophthalmology, and other industries. The Effect of Extrusion on PS-212 Self-Lubricating Materials w.J. Waters, Materials Engineer, Sverdrup Technologies Inc. ; H.E. Sliney, Materials Engineer, Lewis Research Center; and R.F. Soltis, Electrical Engineer, Cortez III The presenters have employed extrusion processing to improve the strength and density of PS-212 ceramics, opening up a wide range of commercial uses for these unique high-temperature materials. A102 chnology and Life Sciences Part 1 Measuring the M~tastatic Potential of Cancer Cells Dr. Dennis R. Morrison, Senior Biotech Scientist, Johnson Space Center; Dr. Howard Gratzner, DNA Sciences Inc.; and Dr. M.z. Atassi, Baylor College of Medicine State-of-the-art digital imaging technology is providing a powerful new tool to diagnose breast, lung, and other forms of cancer, and promises more effective treatment techniques. Immunoconjugates: Magic Bu"ets for Cancer Therapy? Daniel R. Passeri, Technology Licensing Specialist, and Jack Spiegel, Patent Advisor, Office of Technology Transfer, National Institutes of Health Discover how the exciting new technology of immunoconjugates is aiding the fight against cancer; explore current and future licensing opportunities in cancer and other therapy markets, such as arthritis, diabetes, and AIDS. Automated System for Early Breast Cancer Detection Isaac N. Bankman, Senior Research Scientist, Johns Hopkins University Applied Physics Laboratory A new computerized system promises to improve the speed and accuracy of mammogram interpretation, enabling physicians to spot tumors at an earlier stage and accelerate treatment, thereby increasing the patient's chances of survival. Design of Mechanically Compatible Fasteners for Human Mandible Reconstruction Jack C. Roberts, John A. Ecker, and Paul J . Biermann, Senior Professional Staff, Johns Hopkins University Applied Physics Laboratory The presenters will illustrate a design approach that overcomes many of the problems encountered in attaching disease- weakened sections of bone to one another, or a replacement material, during reconstructive surgery. A103 Energy and Environment Part 1: Environmental Technologies Cone Penetrometer Measures Spectral Characterist ics of Soils In Situ Philip G. Malone and Stafford S. Cooper, Geophysicists, U.S. Army Engineer Waterways Experiment Station Army researchers have invented a fiber optic device that measures contamination in soils from fuels or other hazardous wastes. In field tests, it has detected diesel fuel contamination in concentrations as low as a few hundred parts per million. Soil Reclamation and Recovery of Radionuclides and Toxic Metals Dr. A.J. Francis, Microbiologist, Brookhaven National Laboratory A new process for removing metals and radionuclides from contaminated soils, sediments, and sludges holds tremendous commercial potential because it can be applied to a variety of waste forms, generates no secondary waste streams, and causes little soil damage. Recovery of Oil and Solids from Oily Sludges Leonard A. Duval, Chief Executive Officer, RECOTECH Corporation Mr. Duval will describe an energy-efficient and environment- ally-safe process for converting large volumes of oily wastes to valuable raw materials and fuel oil. Low-Cost Dewatering Waste Siurfieli J.B. Peterson, Chemical Engineer, R.H. Church, Mining Engineer, and B.J. Scheiner, Supervisory Metallurgist, Tuscaloosa Research Center The Bureau of Mines has developed a method for dewatering waste mineral slurries that could dramatically reduce the cost of waste disposal in the U.S. G A104 n ormation and Communications Part 1: High-Performance Computing and Networking High-Performance Networks and Supercomputers for Real- Time Flight Simulation Jeff I. Cleveland, Aerospace Technologist, Langley Research Center This presentation will address commercial applications of high- speed data acquisition and computing technology in nuclear process control, power grid analysis, process monitoring, real-time simulation, radar data acquisition, and other key fields. The SPLASH II Attached Processor System Duncan A. Buell, Senior Researcher, Supercomputing Research Center Designed for Sun workstations, SPLASH II achieves supercomputer performance on problems not suited for traditional architectures, such as the filtering of digital data signals. Object-Oriented Tools for Distributed Computing Richard M. Adler, Director of Advanced Development, Symbiotics Inc. Mr. Adler will describe innovative software tools for developing heterogeneous distributed computing systems such as distributed databases and automated manufacturing control systems. The Database Query Support Processor Patrick McCabe, Computer Engineer, Rome Laboratory The Air Force has created a time- and money-saving method for seamless access to heterogeneous databases based on extensions to data dictionary technology. A105 .!If tjacturing Tf!(!hnolollY Part 1 " On Machine Tool" 3D Laser Measurement System William L. Shade, Jr. , Product Manager, Chesapeake Laser Systems Mr. Shade will report on a major boon to manufacturing: an in- process, noncontacting sensor system that rapidly and accurately measures complex, contoured production parts. Application of an On-Machine Gauge for Diameter Measurement Kevin Harding, Principal Member, Industrial Technology Institute Thil'; presentation will focus on the performance and potential commercial applications of the laser gauge described above. On-Machine Capacitance Dimensional and Surface Profile Measurement System Ralph Resnick, MetreX Division Manager, Extrude Hone Corporation The subject invention, an analog probe designed to check the dimensions of complex shapes and contours on a machine tool or in an automated inspection cell, promises an advance over current inspection methods which are expensive, time-consuming, and labor-intensive. Ultrasonic Polishing Randy Gilmore, SoneX Division Manager, Extrude Hone Corporation An ultrasonic polishing process developed for the Air Force offers many advantages in finishing complex parts: no specially shaped tools or complex fixturing are required; handworking can be eliminated; the process operates unattended; accuracy, uniformity and repeatability are outstanding; and the time savings over manual techniques are enormous. For fastest registration fax the fornr on page "P" to (212) 986·7864 A106 A icroelectronicslOptoelectronics Part 1 Two- and Three-Dimensional High-Performance, Patterned Overlay Multi-Chip Module Technology Capt. James C. Lyke, Wafer Scale Electronics Engineer, Phillips Laboratory A novel technique for reassembling bare integrated circuits dramatically improves performance while reducing component size and .weight. The process has commercial applications ranging from desktop computers and workstations to biomedical imaging equipment and telecommunications systems. Improved Performance and Safety for High-Energy Batteries Terrill Atwater, Chemical Engineer, U.S. Army Electronics Technology and Devices Laboratory A microchip-based process continuously predicts the remaining capacity in high-rate batteries and anticipates hazards - all in real time - enabling the production of reliable, safe, and efficient high-energy battery technology. Thin Rechargeable Batteries for SRAM PC Card Memory Protection Dennis N. Crouse, Senior Scientist, EIC Laboratories Development of SAAM PC cards with permanently installed rechargeable cells and electrochromatic low battery voltage indicators promises to free PC users from having to "feed" their cards with coin cells and will allow a quick visual check of stored cards for their battery voltage status. Passive Stacking for Improved Vibration Isolation David A. Noever, Marshall Space Flight Center Space Science Laboratory NASA research in space materials science has yielded a passive stacking scheme that eliminates a broad range of unwanted vibrations below 5 Hz in laser optics, atomic-force microscopy, and other Earth applications. '11 .... 1 ••• National Technology Initiative Concurrent Workshop Series #1 (panelists to be announced) Technology 2002 Tuesday symposia registrants are invited to attend these hands-on workshops, which will cover partnership opportunities in three major areas: Transportation, Aerospace, and Manufacturing. lact .• 1,"'. National Critical Technologies Concurrent Sessions Session B201 Advanced Materials Part 2: Ceramics and Composites A Novel Method for Detection and Characterization of Superconductors B.F. Kim, Physicist, Johns Hopkins University Applied Physics Laboratory Offering applications in process and quality control in supercon- ductor production, a new technique dubbed magnetically- modulated resistance is more sensitive and convenient than conventional detection methods and can characterize the superconductor's granular state. Production of Ultrafine, High-Purity Ceramic Powders Jesse L. Hoyer, Ceramic Engineer, U.S. Bureau of Mines Ms. Hoyer will describe an innovative grinding technology called turbomilling that holds tremendous potential for production of ultrafine high-temperature ceramic powders and whiskers. H Mullite Whiskers and Mullite-Whisker Felt Dr. Inna Talmy, Senior Research Ceramist, and Debbie Haught, Materials Engineer, Naval Surface Warfare Center The Navy has several patented processes for fabricating whiskers and whisker felt composed of mullite, a refractory oxide ceramic with high strengh and temperature resistance, low thermal expansion, and good dialectric properties. The loose whiskers can be used as a composite reinforcement, while the felt has applications as composite preforms and thermal insulation. Graphite/Epoxy Composite Laminates with Co-Cured Interlaminar Damping Layers J. Michael Pereira, Aerospace Engineer, Lewis Research Center Damped composite laminates, fabricated by co-curing viscoelastic damping film with graphite/epoxy prepreg plies, have strong commercial potential in such areas as vibration and sound suppression. B202 Artificial Intelligence Part 1 Expert System for UNIX System Reliability and Availability Enhancement Catherine Q. Xu, Aeronautical Radio Inc. The subject technology acts as an on-line system administrator to diagnose, report, correct, and prevent hardware and software failures in UNIX systems, which do not have any built-in intelligent fault diagnostics or correction capabilities. The Generic Spacecraft Analyst Assistant: A Tool for Developing Graphical Expert Systems Peter M. Hughes, GenSAA Project Manager, Goddard Space Flight Center First developed for spacecraft monitoring, GenSAA graphical expert software can be used to automate data monitoring or fault detection for telecommunications links, computer networks, industrial control centers, and other commercial systems. TARGET: Rapid Capture of Process Knowledge R. T. Savely, C.J. Ortiz, and B.a. Ly, Software Technology Branch, Johnson Space Center The Task Analysis/Aule Generation Tool represents a new breed of software that could profoundly reduce the time, difficulty, and cost of developing knowledge-based system5; for the performance of procedural tasks. Tree Classification Software Wray L. Buntine, Computer Scientist, Research Institute for Advanced Computer Science This presentation will spotlight the IND Tree Package, an AI software tool employing Bayesian tree algorithms that is part of a broad research effort to semi-automate the development of supervised learning algorithms. B203 Biotechnology and Life Sciences Part 2: Medical Technology Automatic Detection of Epileptic Seizures Dale E. Olsen, Project Manager, Johns Hopkins University Applied Physics Laboratory Johns Hopkins researchers have produced an algorithm for use in developing an implantable device that would give epilepsy patients early warning of oncoming seizures and could help treat the seizure with drugs or electrical stimulation. A Fiber Optic Probe for the Detection of Cataracts Dr. Rafat R. Ansari, Research SCientist, Lewis Research Center A compact fiber optic probe developed for on-orbit science experiments has been reapplied to detect the onset of cataracts, a capability that could eliminate physicians' guesswork and result in new drugs to dissolve cataracts before surgery is necessary. Heart Rate Spectral Analysis System Hasan Rahman, Supervisor, Data Systems Engineering, General Electric Government Services Mr. Rahman will report on a Macintosh-based system that performs real-time heart rate analysis during space and life sciences experiments. CALMS: Contextual ALarm Management System Karin C. Loftin, Senior Research Scientist, KRUG Life Sciences Inc. An advanced software system developed to monitor astronauts during space flight is finding new applications here on Earth, particularly to help overcome the problem of integrating mentally fragile children into a classroom environment. B204 E ergy and Environment Part 2: Energy Innovations Solid-State Isotopic Power Source for Computer Memory Chips Paul Brown, Vice President R&D, American Nuclear Society Tiny thin-film isotopic energy converters can be deposited directly onto integrated circuits to provide on-site power for computer memory chips. They are less toxic and last longer than conven- tional chemical batteries, and could run smart credit cards, cardiac pacemakers, or other electronics that don't require large amounts of power. Photovoltaic Power Without Batteries for Continuous Cathodic Protection W. W. Muehl, Sr., Department of the Navy, Coastal Systems Station Mr. Muehl will describe a major advance in the application of photovoltaics: a cathodic protection system for ships, bridges, pipelines, and other structures that doesn't require any auxiliary/ battery backup power. High-Speed Solid-State Circuit Breaker Thomas F. Podlesak, Electronics Engineer, U.S. Army Electronics Technology and Devices Laboratory The Army has developed and installed solid-state circuit breakers that can interrupt 4160V three-phase power mains at no less than 300 microseconds, two orders of magnitude faster than conven- tional mechanical circuit breakers. Variable-Speed Generators with Flux Weakening A.A. Fardoun, EF. Fuchs, and P. W. Car/in, University of Colorado at Boulder Utilization of permanent magnets together with field weakening via stator excitation yeilds lightweight designs for low-speed, high- torque electric machines useful in variable speed applications. B205 Information and Communications Part 2: Computer Simulation and Modeling Industrial Applications of Computational Fluid Dynamics Dr. R.R. Chamberlain, Chief Engineer/Senior Research Scientist, Adaptive Research Corp. This presentation will explore potential uses of CFD technology in such diverse fields as automobile design, materials processing, oil production and recovery, electronics cooling, and environmental management. Scientific Visualization Using the Flow Analysis Software Toolkit Gordon V. Bancroft, Research Scientist, Sterling Software Inc. FAST is a powerful software tool for visualizing and analyzing scientific data on high-performance graphics workstations. Its utility extends from space science to Earth ozone modeling to automotive design. Integration of Design, Thermal, Structural, and Optical Analysis, Including Animation of Thermal Mapping Ruth M. Amundsen, Aerospace Engineer, Langley Research Center Discussion will center on how concurrent engineering can improve efficiency and accuracy in analytical modeling, such as through integration of CAD design with thermal and structural analysis. Data Systems Dynamic Simulator Christopher Rouff, Computer Engineer, Goddard Space Flight Center Mr. Rouff will describe the importance and commercial potential of the DSDS, a discrete-event-based modeler that eases the simulation of complex, high-data-rate, end-to-end systems. B206 Man tjacturing Technology Part 2 A Novel OpticaVDigital ProceSSing System for Pattern Recognition Bradley G. Boone, PhYSicist, and Oodaye B. Shukla, Engineer, Johns Hopkins University Applied PhYSics Laboratory The presenters have developed algorithms that can be imple- mented optically for the extraction of features that are scale and rotation invariant. These features can then be used in conjunction with a digital neural network to perform pattern recognition on images obtained from machine vision systems and other sensors. Vision-Aided Monitoring and Control of Thermal Spray, Spray Forming, and Welding Processes John E Agapakis, Vice President, Automatix Inc., and Jon Bolstad, President, Control Vision Inc. An innovative vision senSing technique developed through the government's SBIR program incorporates intense pulse laser or strobe illumination and synchronized shuttered image sensing to produce a video image free of arc light or glare. This image can then be processed digitally to extract features for process monitoring and control. Robotic Variable Polarity Plasma Arc (VPPA) Welding War/s S. Jaffery, Senior Manufacturing Process Technology, Boeing Defense and Space Group For space station Freedom, Boeing and NASA have achieved an i~dustry first by e~tablishing a production VPPA weld cell featuring eight axes of mollon under automatic control. It produces highly reliable, porosity-free aluminum welds. Firmware Development Improves System Efficiency E James Chern, Materials Engineer, Goddard Space Flight Center, and David W. Butler, Paramax Svstems CorDoration A new eddy current imaging system designed for m~nufacturing processes such as materials dispensing, packing, and sorting improves positional accuracy and reduces wear and tear on the mechanical system. 11,·.1.1.'. NTI Concurrent Workshop Series #2 (panelists to be announced) Workshops will provide practical information in three key areas of interest to U.S. businesses: Partnerships for Technology Transfer; Protecting Intellectual Property Rights and Techni- cal Data; and Financing of Partnerships for Technology Commercialization. Wednesday, December 2 ·:pcj·.*Lii';;' Concurrent Workshops: How To Do Business With The Government (Panelists to be announced) In small working groups, tech transfer experts from leading federal agencies including NASA. the DOD, and DOE will discuss with industry attendees how they can successfully tap into that agency's R&D resources through patent licensing, partnerships, Small Business Innovation Research grants, and other proven mechanisms. They also will cover how the govemment acquires new technology from the private sector. Seating will be limited, so please plan to arrive early. 1000 am - .12.00 pm National Critical Technologies Concurrent Sessions Session C301 .(' c Materials Part 3: Plastics, Polymers, and Rubber Electro-Expulsive Separation System Leonard A. Haslim, Research Scientist, Ames Research Center A dynamic new deicer uses less power and is more compact and efficient than current systems. It can be easily retrofit to aircraft and ships to deice surfaces ranging from frost to one-inch glaze coatings, and has applications in fluid pumping lines, plastic mold releases, and robotic arms. Improved Rubber Compound for Tracked Vehicles Dawn Crawford, Materials Engineer, US Army Fort Belvoir Research, Development, and Engineering Center The Army has produced a tough, temperature-resistant compound that extends the service life of tank track pads by two to three times, saving maintenance costs and time. Commercial possibili- ties include conveyor belts, fenders and bumpers on loading docks, gaskets and seals, and even soles and heels for shoes. Dynamic Hardness Tester and Cure Meter Dr. Walter M. Madigosky, Distinguished Scientist, Naval Surface Warfare Center A prototype apparatus provides fast, accurate data on the mechanical properties of materials in an "in-situ" or manufacturing environment, and could become a standard test item in the rubber and plastics industries. Instrumentation Measures Gas Permeability of Polymeric Membranes Dr. Billy T. Upchurch, Instrument Research Division, Langley Research Center Mass spectrometry is employed to measure the permeability of virtually any gas through polymeric membranes. Practical payoffs: food packaging, contact lenses, and other commercial materials where gas permeability and permselectivity are important. C302 rtijiciallntelligence Part 2 A Software Package for Neural Network Applications Robert H. Baran, Naval Surface Warfare Center Original Backprop is an MS-DOS package of four C-Ianguage programs that enable users to develop neural network solutions to a variety of practical problems in medicine and business. Control of Complex Dynamic Systems by Neural Networks James C. Spall, Principal Professional Staff, Johns Hopkins University Applied Physics Laboratory Mr. Spall will describe how neural networks can be used to control/regulate complex systems for which it is difficult or impossible to build a reliable mathematical model, such as in manufacturing, biotechnology, and environmental control. Adaptive Process Control with Fuzzy Logic and Genetic Algorithms C.L. Karr, Mechanical Engineer, and D.A. Stanley, Supervisory Research Chemist, U.S. Bureau of Mines Using two powerful AI techniques, researchers at the Bureau of Mines have devised simple and versatile adaptive process control systems that efficiently manipulate complex problem environ- ments despite limited feedback. J A Genetic Algorithm Tool for Complex Scheduling Problems Lui Wang, Software Technology Branch, Johnson Space Center Splicer, a genetic-algorithm-based software package developed for scheduling of propellant resupply to space station Freedom, offers a relatively simple, modular, and portable tool for solving a variety of scheduling problems in manufacturing and production. C303 prgy and Environment Part 3: Environmental Technologies Development of a LlDAR Mapping Instrument Fran L. Stetina, Technical Manager, Goddard Space Flight Center NASA has developed a laser ranging device that provides timely and accurate data about Earth features such as topography, bathymetry, forestry, and wetlands. Commercial Applications of a Multispectral Sensor System R. Birk, ASDL Supervisor, Lockheed Engineering & Sciences Co. The Airborne Thermal/visible Land Applications Sensor (ATLAS) offers a versatile test bed for the development of remote sensing applications including environmental monitoring, facilities management, Geographic Information Systems, and mineral exploration. Interactive Forecasting with the National Weather Service River Forecast System George F. Smith, Donna I. Page, and Thomas E. Adams, Hydrologic Research Laboratory, National Weather Service Computational modeling techniques have been applied to create a tool for water resource forecasting, an immense and largely untapped market. One potential application: reservo.ir operators could use river flow forecasts to balance the competing needs of water supply, flood control, and hydroelectric power generation. Application of Space Life Support Technology to Terrestrial Environmental Problems Steven H. Schwartzkopf and Bill Walsh, Lockheed Missiles and Space Co. This presentation will spotlight a series of life support technologies developed to remove trace contaminants from air, purify water, and process solid wastes, and will describe how these technolo- gies can be applied to problems of environmental remediation and pollution prevention. C304 Info mation and Communications Part 3: Computer Graphics and Display Technologies Transportable Applications Environment (TAE) Plus Martha R. Szczur, T AE Project Manager, Goddard Space Flight Center TAE Plus is an advanced WYSIWYG tool for building and managing graphical user interfaces in a wide range of disciplines, including simulation, production, network management, schedul- ing, database management, image processing, and office automation. Advanced Display Object Selection Methods Glenn Osga, Scientist, Naval Command Control & Ocean Surveillance Center Mr. Osga will demonstrate a time-saving interface technology that could dramatically improve the productivity of thousands of computer users. Universal Index Management System Nick Roussoppulos, Vice President, Advanced Communications Technology R-trees software provides an easy-to-use and reliable interface to large pictorial databases; it can be used as an external add-on search capability for commercial database management systems or incorporated into other systems as a spatial access method. A Natural Language Interface for a Geographic Information System Bruce Davis, Geographer, Stennis Space Center Under an SBIR contract, Netrologic Inc. is creating a user-friendly interface for GIS technology that will enable analysts to input English language statements to request information. This will make GIS software more attractive commercially and open new markets such as process control and biomedicine. C305 a Management, Storage, and Processing Part 1 An Application Protocol for CAD to CAD Transfer of Electronic Information Charles C. Azu, Jr., Project Engineer, Naval Command Control and Ocean Surveillance Center An innovative application protocol will enable computer-aided design software developers to transfer files between dissimilar CAD systems without any data loss, negating the current need to reenter parts of the design. Methods for Programming Intelligent Searches of Technical Documents David L. Gross, Computer Engineer, Analex Space Systems The Centralized Document Database provides a common interface to an unlimited number of files of various sizes, with the capability to perform many diversified types and levels of data searches. Legal , medical , and other professionals who devote time to subject review and research would benefit greatly from this time-saving system. An Integrated Information Retrieval and Document Management System L. Stephen Coles, Group Chief Technologist, Jet Propulsion Laboratory Mr. Coles will illustrate an improved method for communicating and storing information electronically that combines scanning, optical character recognition, magneto-optical storage, and multiplatform retrieval technologies. Multispectral Lossy Data Compression Using Vector Quantization S. Jaggi, Senior Scientist, Lockheed Engineering and Science Co. This presentation will explore how a new data compression technique can benefit the handling, storage, and processing of remote sensing , medical , and industria! imaging data. C306 Manufacturing Technology Part 3: Robotics Development of a Dexterous, Redundant Manipulator for Space and Ground Robotics Applications James B. Burke, Odetics Inc. A dexterous robot with seven degrees of freedom and internal force reflection capabilities has been created to tackle jobs that are too dangerous or impractical for humans, such as handling nuclear waste materials or repairing satellites in orbit. An Eight-Degree-of-Freedom Macro-Micro Robot for Precise Force Manipulations Dr. Neville Marzwell, Jet Propulsion Laboratory The development of an automated robot that can handle delicate objects will improve the nation's manufacturing capabilities for such tasks as polishing, finishing, grinding, and cleaning. A Fault-Tolerant Intelligent Robotic Control System Dr. Neville Marzwell, Jet Propulsion Laboratory This presentation will spotlight a knowledge-based fault diagnos- tics and recovery system that can be applied in industrial robots to cope with various unexpected events occurring during the manufacturing process. K ROBOSIM: An Intelligent Simulator for Robotic Systems Kenneth R. Femandez, Marshall Space Flight Center, and George E. Cook, Vanderbilt University A NASA software package aids the design and testing of robots, robot act!on planning, on-line control of robot manipulators, telerobotlc user interface, and training and education. "., .•. ,.ew National Critical Technologies Concurrent Sessions Session 0401 B,ote hnology and Life Sciences Part 3 Three-Channel Biomedical Telemetry System Jeffery c. Lesho and Harry Eaton, Associate Engineers, Johns Hopkins University Applied Physics Laboratory An ingestible electronic pill transmits precise measurements of body temperature, heart rate, muscle strain, and internal pressures. Potential uses include critical health care monitoring, sports medicine, and animal studies. Implantable Stimulator System Restores Motor Function Dr. P. Hunter Peckham, Research Biomedical Engineer, Department of Veterans Affairs Medical Center Learn about a new technique that uses electrical stimulation to restore movement and sensation for people with central nervous system injuries such as stroke and cerebral palsy. Automated System for Analyzing the Activity of Individual Brain Neurons Isaac N. Bankman, Senior Research Scientist Johns Hopkins University Applied Physics Laboratory ~n instrument ~hat reliably records neuron behavior could bring Important new InSights about the workings of the human brain and speed advances in speech processing, computer vision, and memory storage and retrieval. Improved Inhalation Technology for Setting Safe Levels of Exposure to Workplace Chemicals Dr. Bruce O. Stuart, Program Manager, Inhalation Technology Facility, Brookhaven National Laboratory Dr. Stuart will detail an analytical tool for much more reliable risk evaluation and chemical exposure level setting for humans. 0402 E ergy and E""ironmellt Part 4: Ellvironmental Techllologies Active Hydrazine Vapor Sampler Rebecca Young, Manager, NASA Toxic Vapor Detection Laboratory NASA has produced a major advance in personnel safety monitoring: a lightweight, low-cost, easy-to-use, and intrinsically safe device that detects low-level toxic vapors in the air. COP Improvement of Refrigerator/Freezers, Air-Conditioners, and Heat Pumps Douglas G. Westra, Aerospace Engineer, Marshall Space Flight Center A unique non-azeotropic refrigerant mixture offers an efficient, environmentally-safe alternative to ozone-damaging chlorofluoro- carbon (CFC). Novel Hot Water Recirculating Technology Conserves EnergylWater Thomas J . Ingalz, Director, Water Control Products Inc. PROtherm, a home water conservation unit utilizing a state-of-the- art microcontroller and fuzzy logic technology, could obviate "waif water loss (amounting to billions of gallons annually in the U.S. alone), reduce water heating energy requirements, and yield unprecedented convenience to the morning shower and sink user. Variable-Volume Flushing Device for Toilet Water Conservation Louis J. Jasper Jr., Chief, RF Effects and Hardening Technology Branch, Harry Diamond Laboratories The subject invention is more reliable (will not leak) than current flushing devices, is simple and economical , and conserves wa~er by allowing one to choose the amount of water to use for flushing waste. 0403 ation and Communications Part 4: Com uter Software Automated Real-Time Software Development Denise R. Jones, Research Engineer, Langley Research Center, and John J. Turkovich, Section Chief, Automation Technology, Charles Stark Draper Laboratory A new computer-aided software engineering system provides an automated way to generate source code and hard copy documen- tation from application engineering specs, the goal being to reduce the cost of developing and maintaining real-time scientific and engineering sofl'ware while increasing system reliability. Constraint Checking During Error Recovery Robyn R. Lutz, Jet Propulsion Laboratory NASA has developed a technique that allows more accurate modeling of the constraints on process interactions. It can be applied to a wide range of control systems or used as an embedded extension to simulation and CASE tools. Spinoff Technology: Engineering and Scientific Computer Codes Bahman Zohuri and Robert Weinheimer, Galaxy Applied Engineering A host of government computer codes originally developed for mainframe computers have been adapted to PCs and are available for commercial use. Learn how and where you can access this wealth of software. Failure Environment Analysis Tool Applications Ginger Pack, Project Manager, Johnson Space Center, and David Wadsworth, Lockheed Engineering and Sciences Co. FEAT permits analysis of large systems with thousands of nodes so that failure modes and effects can be determined across subsystems, and has additional value as a training tool. 0404 (0 ation and Communications Part 5: Computer Simulation, Video, and Imagin Technolo y Development of Interactive Multimedia Applications Albert Leigh, McDonnell Douglas Space Systems Co., and Lui Wang, Johnson Space Center Several exciting computer-aided training, instructional, and simulation systems incorporating new media forms and technolo- gies will be presented. Visual Communication in Multimedia Cyberspaces Dr. Joseph Psotka, Chief, Smart Technology, US Army Research Institute This presentation will investigate how visual knowledge can be structured to take advantage of advanced computer environments for training, particularly hypertext and virtual reality (VR), and will discuss the development of images for a VR workstation that immerses the user in a 30 computer-generated world. Micro-Video Display with Interactive Ocular Tracking and Voice Control James E. Miller, Encapsulated HARPOON Weapon Warfare Center, Naval Undersea Warfare Center A PC-based micro-video display system incorporating interactive eye tracking and voice command control enables hands-free L computing for such applications as portable training and trouble- shooting, and could prove a valuable aid for the handicapped. Video Conferencing Made Easy D.G. Larsen and P.R. Schwieder, EG&G Idaho Oepartment of Energy engineers have designed a state-of-the-art video conferencing system that combines an array of outstanding features, among which are true multipoint conferencing, user- friendly operation with no full-time operators required, and the potential for cost-effective system expansion. 0405 an facillring Technology Pa,.,t 4: Intelligent Tools An Expert System for Superplastic Forming in Concurrent Engineering Environments Deepak Kohli, West Virginia University; Paul Gill and Suren Dwivedi, Marshall Space Flight Center An object-oriented, knowledge-based system and computer-aided technologies are being developed to enable design and manufac- turing engineers to simulate the metal sheet forming process, leading to improved design and quality. Automated Fiber Placement Composite Manufacturing John H. Vickers, Marshall Space Flight Center The subject invention is a tremendous advance in automated composite manufacturing established at the Marshall Center's Productivity Enhancement Complex, where NASA engineers work with industry and university experts to solve materials and processing problems. Expert System for Signal Validation and Equipment Surveillance . Kenny C. Gross and Ralph M. Singer, Managers, Argonne National Laboratory An artificial-intelligence-based expert system has been produced for signal validation and equipment surveillance in industrial applications that require high-reliability , high-sensitivity annuncia- tion of degraded sensors, discrepant signals, or the onset of system disturbances. Application of Space Time Neural Networks to Detect Tether Skiprope Phenomena James A. Villarreal, Johnson Space Center Numerous industrial and commercial control applications could benefit by adopting a patented neural network architecture first developed to detect and predict oscillations of tethered satellites in Earth orbit. 0406 ·C oelectronics/Oploelectronics Part 2 Wireless Infrared Communications for Space and Terrestrial Applications James W. Crimmons, President, Wilton Industries Inc. For space station Freedom, NASA sponsored development of infrared (IR) systems that provide simultaneous multi-channel, multi-user communications for both voice and data. Mr. Crimmons will explore potential- and actual- "spinoffs" of this technology, including a wireless IR telephone system and wireless personnel tracking products. Flexible High-Speed CODEC J. V. Wemlund and G.P. Segallis, Harris GCSD An advanced high-speed error correction decoding technique provides substantial coding gains with limited bandwidth expan- sion compared to the uncoded bit-error-rate performance of several common modulation methods. Commercial applications include cellular communications and high-data-rate links used to transfer video images. Ultra-Stable Low-Phase-Noise Dielectric Resonator Stabilized Oscillator (ORO) Muhammad Mizan, Electronics Engineer, u.s. Army Electronics Technology and Devices Laboratory The Army has fabricated a microwave ORO with better phase noise and temperature stability performance than current models. Applications for the small , lightweight, low-cost oscillator include cellular phone systems and built-in test equipment. Excimer Laser Processing of Backside-Illuminated CCDs Stephen D. Russell, Scientist, Naval Command Control & Ocean Surveillance Center Laser implantation of dopant atoms into the backside of backside- illuminated charge-coupled devices repairs defective pixels and improves the dark current and spectral response. This process is particularly useful for solid-state imaging detectors requiring a wide spectral response and low-light-level detection. ••• ,cui£lUl Track #1: University Tech Transfer Opportunities (panelists to be announced) In this highly interactive session, technology transfer experts from MIT, Stanford, and other top schools will tell you about specific opportunities for licenses, R&D partnerships, and technology incubators. Track #2: International Technology Forum: Foreign Inventions for U.S. Benefit (panelists to be announced) Leading technology managers from around the globe will show you their nation's portfolio of technologies available for transfer and discuss key contacts and resources for follow-up. ttl".'I'I't'U Third Annual Technology Transfer Awards Dinner - Hyatt Regency Hotel Keynote Speaker: Norman Augustine, Chairman and CEO, Martin Marietta Corporation Achievement awards will be presented to federal employees and private sector companies who have made important strides in translating innovative ideas into products and processes that benefit the national economy and daily life. Thurs ay, December 3 1;1J·.*Sii'''' Concurrent Workshops: How To DO Business With The Government (Part 2) (panelists to be announced) 1000 am - 12.00 pm National Critical Technologies Concurrent Sessions Session E501 Advaced Materials Part 4 Applications of Phase Change Polymers in Fibrous Substrates Tyrone L. Vigo and Joseph S. Bruno, US Department of Agriculture A process for insolubilizing polyethylene glycols onto a variety of fibrous substrates produces materials with improved properties and fabrics exhibiting novel thermal adaptability, reduced static charge, resistance to oily soils, and smooth drying properties. Rust TransformersJRust Compatible Primers Dario A. Emeric, Chemist, US Army Belvoir Research, Development, and Engineering Center The Army has developed a compound for use on a rusted surface before application of an organic coating that obviates the need for sandblasting or removing the adherent corrosion. M Method for Predicting Properties of and Tailoring Salt Solutions for Industrial Processes Dr. Moonis R. Ally, Oak Ridge National Laboratory This unique method can predict a wide range of thermodynamic properties of concentrated aqueous salt solutions, both single-salt and multiple-salt, to enable determination of system pressures, boiling temperatures, and heats of mixing, dilution, evaporation , and condensation. An X-Ray Scatter Approach for Nondestructive Analysis of Low Atomic Numbered Elements H. Richard Ross, Sverdrup Technology Inc. A nondestructive analysis technique based on the intensity ratio of Compton and Rayleigh scatter in x-ray fluorescence spectra is used to define light element components in alloys, plastics, and other materials. E502 . ·ciallnlelligence Part 3 An Artificial Intelligence-Based Structural Health Monitoring System for Aging Aircraft Joseph E. Grady, Aerospace Engineer, Lewis Research Center A new system monitors vibrations of in-service parts and, using a computer-based pattern recognition algorithm, estimates the damage and structural degradation of aging airframes. The Ground Processing Scheduling System Michael J. Deale, Senior Engineer, Lockheed Space Operations Co. GPSS is a general-purpose AI-based scheduling tool that aids in managing large, resource- and configuration-constrained scheduling problems. It can be applied to scheduling tasks in plant management, construction, operations , and transportation. Reactive Control and Reasoning Assistance for Laboratory Instruments David E. Thompson, Senior Scientist, Ames Research Center Interactive software developed at NASA autonomously controls scientific laboratory instruments and provides data analysis of real-time data in support of dynamic refinement of experiment control. The technology has been applied to a differential thermal analyzer and a gas chromatograph. Knowledge From Pictures Walt TruszkOWSki, Head, Automation Technology Section, Goddard Space Flight Center A new tool configures an expert system's rule base by an automated analysis of a piciure - a graphical representation of some target system to be supported by the expert system's diagnostic capabilities. This rule base could be used to automate fault detection, isolation, and repair of the target system. E503 (J hnology and Life Sciences Part 4: Comouters in Medicine Optimal Design of Composite Hip Implants D.A. Saravanos, Senior Research Associate, Lewis Research Center STAT, a structural optimization code for propulsion components, has been adapted to automate and improve the design of composite orthopedic implants. Finite Element Analysis of a Composite Artificial Ankle Leigh Ann Perkins, Aerospace Engineer, Marshall Space Flight Center, and Blaise E. Czekalski, Software Consultant, Integraph Corp. NASA conducted an ankle strength analysis to aid in the design of a composite artificial ankle. A 3D finite element model of the ankle was created from ANSYS layer shell elements and various analyses performed to ensure that the joint met spring, strength, and stiffness requirements. Design of a Portable Powered Seat Lift Bruce Weddendorf, Structural Designer, Marshall Space Flight Center A battery-powered device assists people suffering from degenera- tive hip or knee joints in sitting and rising from sitting. Though the size of a thin briefcase, the seat can lift a user weighing up to 300 pounds to nearly standing. Microcomputer-Based Software for Biodynamic Simulation N. Rangarajan, President, GESAC Inc. Mr. Rangarajan will describe DYNAMAN , user-friendly biodynamic simulation software that is easily installed on a PC. Based on the Articu lated Total Body model previously available only on larger computer systems, the software can be used to predict occupant motion during an automobile or aircraft crash . E504 Data Management, Storage, and Processing Part 2 The Data Egg: Single-Handed Text Entry Without Positional Constraints Gary L. Friedman, Technical Group Leader, Jet Propulsion Laboratory JPL researchers have devised a small , handheld unit that allows text entry with only one hand. The Data Egg can be operated in any position , either autonomously or tethered to a PC. MIRAGE: The Data Acquisition, Analysis, and Display System Hasan Rahman, General Electric Government Services MIRAGE provides a portable desktop unit capable of real-time acquisition , monitoring, archival , and processing analysis. The low-cost system, which features a Macintosh user interface, can acquire either parallel data from a high-rate demultiplexor interface or packetized data from a DEC net interface. Tunneling Magnetic Force Microscopy Dr. Edward R. Burke, Laboratory for Physical Sciences This invention uses a flexible magnetic probe instead of the fine- wire probe used in scanning tunneling microscopes to provide improved atomic-level resolution for imaging surface topology. The Operator Performance Support System Marlen Z. Conklin, System Engineer, and Eugene Walker, Program Manager, Naval Command Control, and Ocean Surveillance Center A proposed operator station incorporates elements of video and image databases, productivity software, interactive computer- based training, text databases, expert programs, and human factors engineering to assist in complex systems operation. E505 Manufacturing Technology Part 5 A New Technology for Manufacturing Scheduling R.S. Hornstein, Office of Space Communications, NASA Headquarters, and J.K. Willoughby, Avyx Inc. Derived from space systems operations, a new technology can produce finite capacity schedules for both discrete and process manufacturing environments. Systems built with the technology are easy to adapt or extend and can accommodate machine and routing alternatives and software/hardware constraints. Three-Dimensional Laser Window Formation for Industrial Applications Vincent G. Verhoff, Aeropropulsion Engine Components Project Engineer, Lewis Research Center NASA has developed a unique glass molding process for forming 3D compound-curvature laser windows to extreme accuracies. Such windows are an integral component of specialized non- intrusive laser data acqu isition systems employed in compressor and turbine research testing facilities , and could be used for view ports in testing devices or factory machines . N High-Performance Sapphire Windows Stephen C. Bates, Senior Engineer, Advanced Fuel Research Inc. , and Larry C. Liou, Aerospace Engineer, Lewis Research Center A project is underway to strengthen sapphire to compare with steel and to develop mounting techniques to minimize thermal stress during its use. Sapphire windows will afford a moderately- priced glass alternative in applications where optical access must be maintained but the pressure or temperature is too high to permit the safe use of glass. A Dual-Pressure, Ultra-Pure Gas Delivery Vessel Assembly Isaac Maya, Director of R&D, Arrallnc. A new gas vessel assembly delivers ultra-pure gas at exhaust pressures of 6000 psi and 100 psi , with an accuracy of 10 psi. Ideal for fast, high-pressure discharge applications, the device is extremely lightweight and offers very long storage life. E506 Sensors and Signal Processing On-Line Process Analysis Innovation: The New Shunting Dielectric Sensor Technology Frank A. Waldman, PreSident, Axiomatics Corp. Innovative sensor technology incorporates a shunting electrode and conventional electrode pair within a dielectric sensor to greatly magnify the changes in dielectric measurements due to changes in the composition of a material in the electric field. A Modular, Programmable Measurement System for Physi- ological and Spaceflight Applications John W. Hines, Research Scientist, Ames Research Center The NASA Ames Sensors 2000! program has produced a compact, modular, programmable sensor signal conditioning and measurement system suitable for a variety of commercial applications. Smart Sensor Method and Apparatus Tom Koger and Vivien Cambridge, Sverdrup Technology Inc. A microprocessor-based software system employs a unique signal processing technique to speed sensor response time. Designed for application to hydrogen leak sensors , it reduces response time from 1.5 minutes to 8.5 seconds and cou ld be applied to such devices as electronic medical thermometers. ATTIRE: Analytical Tools for Thermal InfraRed Engineering S. Jaggi, Senior Scientist, Lockheed Engineering & Science Co. ATTIRE, a thermal sensor simulation software package, simulates the various components of a sensor system and allows each subsystem to be analyzed independently. Performance param- eters can then be integrated to obtain system-level information. II.! •• B.!.ISWI Track #1: University Tech Transfer Opportunities (Part 2) (panelists to be announced) Track #2: International Technology Forum: Foreign Inventions for U.S. Benefit (Part 2) (panelists to be announced) Preregister and $ave Complete the registration form on the next page and mail with check or money order (if applicable) to the Technol- ogy Util ization Foundation , or fax it with credit card information to (212) 986-7864. To register by phone, call (800) 944-NASA. Government organizations may use a purchase order to register. Deadline for preregistration is November 20. Complete Registration Three-Day Symposia/Exhibits One-Day Symposia/Exhibits Awards Dinner Only Exhibits Only By 11 /20 On-Site $240 $285 $150 $195 $75 $95 $95 $105 - No Charge- See next page for descriptions of registration packages. Preregistrants will receive written confirmations via mail along with their name badge, reception/dinner tickets , and tickets for optional tours (listed below). Badge holders and computerized registration cards must be picked up in person at the Baltimore Convention Center (Pratt Street Lobby) during the following hours: On-Site Reg';stration Hours Monday, Nov. 30 Tuesday, Dec. 1 VVednesday , Dec. 2 Thursday, Dec. 3 9:00 am - 5:00 pm 7:00 am - 5:00 pm 7:00 am - 5:00 pm 7:00 am - 4:00 pm Spouse & Post-Meeting Tours Tour 1 Baltimore: Its Sights & Seaport Wednesday, Dec. 2 12:00 - 4:30 pm Walking tour of the exciting redeveloped Inner Harbor. Begin with lunch at the Chart House Harborside Restau- rant, then enjoy a tour of the USF Constellation and a view of the city from the observation deck of the World Trade Center. The remainder of the afternoon will be spent at the famous Baltimore National Aquarium . $36 per person. Tour 2 Baltimore City Tour Thursday, Dec. 3 9:00 am - 12:30 pm This narrated tour will let you experience historic Baltimore from the comfort of your motorcoach. Drive by the famous homes of the Otterbein and Federal Hill with stops at the George Peabody Library, the Kirk-Steiff Silversmith's Factory Store, and Fort McHenry. $18 per person. Tour 3 Washington, D.C. Post-Meeting Tour Friday, Dec. 4 9:00 am - 5:00 pm Just an hour drive by motorcoach to our nation's capital where you will spend a full day visiting government buildings, historic monuments, Arlington National Cem- etery, and the Smithsonian Complex. $25 per person. Tours will depart from and return to the Baltimore Conven- tion Center. If a tour is sold out or does not meet minimum requirements, your money will be refunded. Cancellations must be received by November 1, 1992. o Special Hotel Rates Book early! Hotel space is limited and requests will be filled on a first-come, first-served basis.When making reservations, you must identify yourself as a participant in the Technology 2002 conference to receive the speCial rates. Hyatt Regency (headquarters hotel) (800) 233-1 234 Holiday Inn (301) 685-3500 Omni Inner Harbor (800) 843-6664 Il~·· o lombarclStreel Single $1 03 $63 $63 BalilmoreSt,ul Double $115 $64 $63 l .. s",,, INNER HARBOR K,Hlghw.y 1 - Baltimore Convention Center 2 - Hyatt Regency 3 - Omni Inner Harbor 4 - Holiday Inn (Bold rule line represents Overhead Pedestrian Skywalk) Transportation To/From Baltimore Baltimore is serviced by AMTRAK which is located at Pennsylvania Station, five minutes north of the downtown area. BWI Airport is approximately ten miles from the city center and is serviced by more than a dozen airlines. Ground transportation fares are as follows: BWI Shuttle Express Downtown hotels - $8.00 one way/$12.00 round trip The shuttle runs every 1/2 hour from 6 am - 11 pm daily. Tickets can be purchased in the baggage claim area at BWI Airport. Taxi Downtown hotels - $12.00 - $16.00 Car Rental Discounts Technology 2002 attendees are entitled to a special AVIS RENT-A-CAR discount. Please call (800) 331-1600 and refer to the Technology 2002 Discount Number: B796477. Discount is valid Nov. 24 " Dec. 11 and includes unlimited mileage. Queslion.~? Call Wendy Janiel at (212) 490-3999. TECHNOLOGY 2002 December 1-3, 1992 Baltimore, MD Convention Center REGISTRATION FORM Your Badge Will Be Printed From This Information: NAME ________________________________ __ TITLE ________________________________ __ COMPANY ______________________________ _ ADDRESS ________ ~ ____________________ __ CITY/STIZIP ______________________________ _ PHONE ________________________________ __ Please use a separate form or photocopy for each registrant. Be sure to answer all questions below. Which of the following best describes your industry or service? (check one) A) 0 Aerospace B) 0 Electronics C) 0 Computers D) 0 Communications E) 0 Automotive F) 0 Chemicals G) 0 Materials H) 0 Power/Energy I) 0 Biomedical J) 0 Transportation K) 0 L) 0 M) 0 N) 0 0) 0 P) 0 Q) 0 R) 0 S) 0 T) 0 Your major responsibility is: (check one) Government Defense Industrial Equip. Appliance Manuf. Consumer Goods Research Lab University Consultant Library Other _________ _ A) 0 Management other than engineering B) 0 Engineering management C) 0 Engineering D) 0 Research E) 0 Other (specify), __________________ _ Your principal job function is: (check one) A) 0 General & corporate management B) 0 Design & development engineering C) 0 Engineering services - Tests/Quality D) 0 Basic Research E) 0 Manufacturing & Production F) 0 Purchasing & Procurement G) 0 Other (specify) __________________ _ Which of these products do you recommend, specify, or authorize the purchase of? (check all that apply) A) 0 Electronic components B) 0 Board-level electronics C) 0 Electronic systems D) Software E) 0 ComputersIWorkstationsiPeripherals F) 0 CAD/CAE/CAM/CASE G) 0 Mechanical components H) 0 Joining/fastening technology I) 0 Materials J) Plastics & composites FOR FASTEST REGISTRATION Fax to (212) 986-7864 or call (800) 944-NASA OR MAIL THIS FORM TO: Technology Utilization Foundation 41 East 42nd Street, Suite 921 , New York, NY 10017 QUESTIONS? Call (800) 944-NASA or (212) 490-3999 Enter Total $ 1. COMPLETE REGISTRATION $240 ................. .c ) Includes admission to Technology 2002 and National Technology Initiative symposia, workshops, and exhibits for all three show days (Dec. 1-3); a ticket to the Opening Reception on Monday evening, Nov. 30 and to the Technology Transfer Awards Dinner on Wednes- day evening, Dec. 2; and a set of the official Technology 2002 proceedings. 2. THREE-DAY SYMPOSIA/EXHIBITS $150 ........ ( ) Covers admission to the Tech 2002lNTI symposia, workshops, and exhibits Dec. 1-3. ( ) 3. ONE-DAY SYMPOSIA/EXHIBITS $75 .............. ~ ______ ~ Check day(s) : 0 Tues. (includes NTI) 0 Wed. 0 Thurs. 4. AWARDS DINNER ONLY $95 ......................... .C~ ______ ~) 5. EXHIBITS HALL ONLy .... ............ ...................... . ( FREE ) Check day(s): 0 Tues. 0 Wed. 0 Thurs. ( ) 6. SPOUSE/POST-SHOW TOURS ........................ _____ ~ o Tour 1 - Baltimore Sights & Seaport $36 o Tour 2 - Baltimore City $18 o Tour 3 - Washington, D.C. $25 7. ENTER TOTAL PAYMENT DUE .. ..................... .C ) Checks must be made out to the Technology Utilization Foundation. If you are charging your registration to a credit card, complete the following section. Check one: 0 Master Card 0 Visa 0 AmEx CARD NUMBER EXP. DATE SIGNATURE DATE Registrations and Awards Dinner reservations are transferable and may be cancelled until November 20, 1992 subject to a $50 cancel- lation fee. After that date no cancellations will be refunded. Return with payment to: Technology Utilization Foundation 41 East 42nd Street, Suite 921, New York, NY 10017 K) 0 Ferrous & nonferrous metals L) 0 Ceramics 1'llliRliGIS11iR BY i\ TO VliiJlIJliR 2f} M) 0 Vacuum/cryogenics N) 0 Communications/fiber optics 0) 0 Positioning equip/motion control P) 0 Industrial controls/systems Q) 0 Data acquisition/recorders R) 0 Videolimaging technology S) 0 Sensors/transducers T) 0 Test/measurement instruments U) 0 Lasers/optics V) 0 Laboratory equipment W) 0 Engineering dept. equipment AND$AVE Take A Moment Now To Complete This Form And Reserve Your Place At Technology 2002, America's Premier Technology Showcase. p Mechanics Tool Would Grip Round Electrical Connectors One connector could be installed and removed without disturbing closely spaced neighbors. John F. Kennedy Space Center, Florida A proposed modified version of a com- mercially available tool would make it easier to mate and demate round, bayonet- mount, multipin electrical connectors in densely populated connector panels. With the tool, it would be unnecessary to re- move adjacent connectors to gain access to the connector of interest. The result would be a saving of time and effort. The tool would include a cylindrical shell that would partly encircle the connector (see figure). A shaft with a \.4 -in. (6.35-mm) drive socket would be spot-welded to the shell. The inner surface of the shell would be smooth and would include a tapered lip. The inner surface of the lip would grip a knurled outer ring on the connector. A torque wrench could be inserted in the drive socket. The use of the torque wrench would ensure that the allowable torque is not exceeded. In addition, the tool is designed to slip, without damaging the connector, if the applied torque becomes excessive. A set of tools like this one could be built. Each tool would match a standard connec- tor size. This work was done by Terrence L. Camarata of McDonnell Douglas Space Systems Co. for Kennedy Space Center. For further information, Circle 31 on the TSP Request card. KSC-11406 The Tool for Instal- lation and Removal of Round Connec- tors would be made of stainless steel. The length and di- ameter of the cylin- der would depend on the size of the connector shell to be gripped. 1-90· Gap--\ TOP VIEW About 0.030 In. Diameter Depends on Size of Connector To Be Gripped About 1 In. Depending on Siz. of This Ar •• Should Be Approximately 0.005 In. larger Than the Diameter of Connector Shell , Thus the Variance In the ~ 0.020 In. % Connector To I e. Grlpped t 0.100 In. Lip Wall Thickness. -++'11':1--+ Taper From 0.400 In. 0.020 In. to 0.050 In. Maintain 0.050 In. Thickness SECTION A-A MAGNIFIED. SHOWING TAPER AT LIP 1/4-ln.-Orive Socket Shaft Joystick With Cable Springs Offers Better Feel Nonlinear compliance accommodates better the natural reactions of the hand and brain . Goddard Space Flight Center, Greenbelt, Maryland and distances between segments. Figure 2 illustrates an example of posi- An improved control joystick allows mo- tion in 6 degrees of freedom and is biased toward the central position and orienta- tion by 16 segments of cable that serve as springs. In comparison with typical prior joysticks, this one is more comfortable for the operator; consequently, it increases the operator's ability to exert control and re- duces the operator's fatigue. The knob and handle of the joystick are mounted on an upper U-bracket. A lower U-bracket is mounted on a stationary sup- port. The upper and lower U-brackets are joined by the 16 segments of cable clamped variously to the upper and lower U-brackets and to intermediary suspended angle brackets; in effect, the assembly is a cable- sprung universal joint (see Figure 1). NASA Tech Briefs, September 1992 The improvement in feel and control results in large part from the nonlinear compliance of the cable-spring assembly. Whereas prior joysticks have exhibited nearly linear variations of restoring spring forces with displacements, this joystick ex- hibits nonlinear variations, which accom- modate better the natural reactions of the hand and brain. Therefore, the operator can function better as part of a feedback control loop. The compliance (including the linear and nonlinear components of its respons- es in the various degrees of freedom) can be adjusted by choice of the lengths of the segments of cable; the diameter, material, and number of strands; the degree (if any of pre-twist of the strands) and the angles tion and angle sensors that could be add- ed to the joystick assembly for control of a six-degree-of-freedom robot or other sys- tem. In this case, the sensors are linear variable-displacement transformers [also called linear variable-differential transform- ers (LVDT's)]. One end of each LVDT is mounted in a ball-and-socket or other ro- tary joint on a plate affixed to the upper U-bracket; the other end is mounted simi- larly on a plate affixed to the lower U- bracket. The mounting positions and orien- tations of the LVDT's are chosen so that the changes in their lengths yield informa- tion on the commanded changes in the six degrees of freedom. By use of the ap- plicable vectorial weighting equations, a computer converts the LVDT outputs into 99 Figure 1. The Segments of Cable in this joystick assembly provide nonlinearly varying restoring spring forces , which feel better to operators than do linearly varying spring forces. the six command signals. This work was done by James Kerley and Wayne Ecklund of Goddard Space Flight Center. For further information, Cir- cle 35 on the TSP Request Card. This invention is owned by NASA, and a patent application has been filed. In- quiries concerning nonexclusive or ex- clusive license for its commercial deveiop- ment should be addressed to the Patent Counsel, Goddard Space Flight Center [see page 24]. Refer to GSC-13187. Figure 2. LVDT's measure their own extensions and re- tractions , providing information on the relative position and orientation of the joystick. VIEW OF LVDr. FROM TOP, OMITTING PLATES AND U·BRACKETS Plate Attached to Upper U·Bracket VIEW A·A, SHOWING PLATES Systematic Disturbance of Optimal Rotational Trajectory The rotating body would be made to wobble in a prescribed manner. Ames Research Center, Moffett Field, California An algorithm introduces a systematic disturbance into an otherwise optimal rota- tion of a body from a prescribed initial to a prescribed final orientation. An optimal rotation for this purpose is defined as a rotation (usually at constant angular veloci- ty) through an angle a about a single fixed axis specified by Euler's theorem and known as the Euler axis. The perturbed rotational trajectory and the algorithm were devised for use in conjunction with a mo- tion-control program and a three-dimen- sional computer-graphical display to study the ability of observers to distinguish be- tween optimal and suboptimal rotational trajectories. The perturbed or suboptimal rotational trajectory is the rotational analog of the 100 This Perturbed Trans- lational Trajectory is a simplified , two-di- mensional analog of the perturbed three- dimensional rotational trajectory. In the rota- tional case, the axis of rotation at time tdevi- ates by angle v(t) from the optimal (fortime ~ axis of rotation. a Initial Deviated Veloci ty bf b v(t) _---y,/ (t f) \!----- A(t) ---;::r " A\! / ,/ Remaining Optimal .... ,/ / (Most Direct) .... / Trajectory ,/ Ao Initial Optimal (Most Direct) Trajectory NASA Tech Briefs, September 1992 perturbed two<1imensional translational tra- jectory illustrated in the figure. The optimal translational trajectory would be defined as constanf speed along the straight line from initial point bo at time to to final point b, at time t, . The perturbed or suboptimal translational trajectory is specified in this case by making the velocity vector at time t deviate by angle Jl(t) from the straight line between the deviated (nonoptimal) position at time t and the prescribed final position. The deviation is specified by tan v(t) = [R(t)/Ro(tWtan Vo where Ro = the distance from bo to b, along a straight line, R(t) = the distance from the point on the actual trajectory to b, along a straight. line, v 0 = the pre· scribed initial deviation at to' and e is a prescribed exponent that, along with v 0' determines the shape of the trajectory. The optimal rotational trajectory through angle a from initial orientation u to final orientation v is given by the quaternion ~~0~n((~/1~ qu- v = ey sin (a/2) ez sin (a/2) where ex' ey' and ez are the direction cosines of the Euler axis in an x, y, z Carte- sian coordinate system. The disturbance is introduced in the form of a deviation of the actual axis of rotation from the optimal one, like the nutation (wobble) of a top. In analogy with the translational case, the in- stantaneous axis of rotation at time t is made to differ by angle v(t) from the in- stantaneous Euler axis of rotation between the deviated (nonoptimal) orientation at time t and the prescribed final orientation. The deviation is specified by tan v(t) = [a(t)/ao(t)]etan Vo where ao = the angle of rotation about the initial Euler axis from the prescribed initial to the prescribed final orientation, a(t) = the angle of rotation about the Euler axis at time t from the orientation at time t to the prescribed final orientation, Vo is the prescribed initial angular disturbance, and e is an exponent as before. The algorithm effects the rotational trans- formations and solves the differential equa- tions necessary to compute the disturbed trajectory. The motion-control computer program that incorporates this algorithm involves (1) precomputation of those vec- tors, matrices, and quaternions that re- main constant for all trajectories and (2) real-time computations of rotational paths and deviations from the most direct paths. The program is incorporated into an ex- perimental control program for psychophys- ical studies of human observers' sensitivi- ties to perturbed and optimal trajectories. This work was done by Arthur J. Grunwald and Mary K. Kaiser of Ames Re- search Center. Further information may be found in NASA TM-101089 [N90-10575], NASA Tech Briefs , Se tember 1992 '~n Algorithm for the Systematic Disturb- ance of Optimal Rotational Solutions." Copies may be purchased [prepayment required] from the National Technical In- formation Service, Springfield, Virginia 22161, Telephone No. (703) 487-4650. Rush orders may be placed for an extra fee by calling (800) 336-4700. ARC-12700 Self-Aligning Cranked Latch This mechanism is useful where the latching process cannot be viewed. Marshall Space Flight Center, Alabama The latching mechanism illustrated in the figure is designed to be quick-acting, self-aligning, and rigid when ·set. There is no need to provide shims or to adjust otherwise for looseness. The latch is espe· cially useful in "blind" applications, in which users cannot observe the mating and latching process. The latching mechanism is a driven-pin, rigidized-clevis device in which the pin is actuated by a crank and slider. When the pin is fully retracted (that is, when the crank is at the 135°, or open , position), a port near the end of the latch body is placed over a lug on the structure to which the latch is to be attached (such as a rack). The crank is then turned, either by hand or by a motor. This action advances the pin toward the top-dead-center (0°) position. As it moves, the pin continuously hunts for the latched position as it follows the tapered, smooth ramps in an insert in a spherical bearing in the lug. The spherical bearing provides a gimbal angle of 5° so that it can readily capture the pin. As the crank is turned further, the pin begins to push on a bushing that is lightly loaded against the pin by a coil spring. Our· ing the final phases of cranking, the ramped surfaces on the faces of the bushing and the insert in the bearing augment the align- ment of the pin and simultaneously provide support against shear loads. As the pin ap- proaches top dead center, it forces the bushing tightly against a mating surface on the insert in the spherical bearing. As the pin reaches top dead center, a spring wash- er deflects slightly and allows the connect- ing link to continue overcenter and lock in- to a stable position against a hard stop at an overcenter angle of 5° . The spring washer is designed to pro- HURRY If you've been waiting for the PERFECT time to buy Tufoil, NOW's the time! Check the coupon below for details and REALLY change your oil.. • into a patented engine treatment . 1-800-922-0075 ORDER TODAY r--------------------------1 YOU BUY TOTAL COST YOUR FREE GIFT 1_ 1 8-0 UNCE $ 17.75 Coupon exp 12/31 /92 1_ 2 8-0 UNCE $ 29.00 ~ I 8-OUNCE FREE 1_ 1 QUART $ 38.95 .. 1 8-OUNCE FREE 1_ 1 GALLON $ 131.00 ~ 2 8-OUNCE FREE 1 --1 Here's my check _ , money order _ , credit card _ for $ ___ _ I VISA- MC_AM.EX_ # Exp_ I NAME ____________________________________ __ I STREETADDRESS ______________________________ _ I CITY, STATE, ZIP CODE ______________ __ __ I ~ Fluoramics, Inc. 18 Industrial Avenue N.J. reSidents, add 6% sales tax. I~~~ ___ ---~~~~~~-~~~~~~~~~~ For More Information Circle No. 315 101 "'Ii rt - A ... ... . ~ . -- ~ . : i Adjustable Hard Stop for Crank in " locked" Position 102 S' ILOCkedj Clevis G Sl ider CRANK IN "OPEN" POSITION CRANK IN "LOCKED" POSIT10N Clevis Spring-Washer Spring SlIctfng SECTION A-A WITH CRANK AT O· The bc700LAN GPS N Time Server receives time from the Positioning System (GPS) sate I constellation, maintaining a high precision (100 nanosecond) primary local time standard. Client worksta- tions synchronize their clocks to this local standard using the Internet Network Time Protocol. In addition to network time service, IRIG Time Code and Digital Synchro- nization signals are available. • Millisecond Resolution on LAN • Microsecond Resolution with IRIG Time Code. • Internet Protocols BANCOMM, DIVISION OF DATUM INC 6541 Via del Oro, San Jose, CA 95119 A l A vide as much locking force as possible without requiring excessive torque on tre crank. As it locks, the pin retracts about 0.005 inch (0.13 millimeter) from its most extended position. This oork was done f:Jy John W Redmon, Jr. , W Neill Myers, and Jeffrey Finchenor of Marshall Space Flight Center and Ronald Markovitch and Norris E. Vaughn, Jr., of Sverdrup Technology, Inc. For further information, Circle 54 on the TSP Re- quest Card. Inquiries concerning rights for the com- mercial use of this invention should be ad- dressed to the Patent Counsel, Marshall Space Flight Center [see page 24j. Refer to MFS-28591. When The Latch Is Open , the slider-and- crank linkage is folded, and the pin is re- tracted into the latch body (top). When the latch is locked, the linkage is extended slightly beyond the top-dead-center position , and the pin engages the insert in the spherical bearing in the lug (middle). NETWORK For More Information Circle No. 658 NASA Tech Briefs, September 1992 Modular Heat Exchanger With Integral Heat Pipe The number of critical brazed joints is reduced. Lewis Research Center, Cleveland, Ohio A modular heat exchanger with an inte- gral heat pipe has been shown to be effec- tive in transporting heat from a source to a Stirling engine. The modular units are in- tended to be an alternative to more-com- plicated heat exchangers that depend on the integrities of thousands of brazed jOints. The proposed modular heat exchanger would contain only 40 brazed tubes, in contrast with a competing design that calls for 7,000 such tubes. A simplified version of the modular heat exchanger was demonstrated in a small Stirling engine. The test heat exchanger con- tained only 3 heat-exchanger modules in- stead of the 40 that would be used in the full-scale Stirling engine, but the operating thermal load per module was similar to that of the full-scale engine design. Each module transported heat at the rate of 1,759 W from a source temperature of 702°C to a sink temperature of 623 °c. evaporator. In the test engine, the heat comes from electrical resistance; in the in- tended application, the heat would come from a nuclear reactor. The sodium vapor flows to the condenser, where it gives up its heat to helium gas, turning into liquid as it does. The helium is the working fluid of the Stirling engine. The liquid sodium is re- cycled to the evaporator through a sintered- metal-powder wick. This work was done by Jeffrey G. Schreiber of Lewis Research Center. Fur- ther information may be found in NASA TM-102097 [N89-25078], "Initial Character- ization of a Modular Heat Exchanger With an Integral Heat Pipe." Copies may be purchased [prepayment required] from the National Technicallnfor- mation Service, Springfield, Virginia 22161, Telephone No. (703) 487-4650. Rush orders may be placed for an extra fee by calling (800) 336-4700. Heat-Pipe Evaporator Helium-Gas Manifold Regenerator Stutter [~~~~~~~tcooler In each module (see figure), heat from the source vaporizes liquid sodium in the LEW-15008 Three Heat·Exchange Modules like this one supply heat to a test engine operating on the Stirling cycle. Questar SZMIOO RESOLVE 1.1 MICRONS FROM A 15 CM WORKING DISTANCE No other optic on the market even approaches the magnification, resolution, and distortion-free images of a Questar Long Distance microscope. For small scale measurement, positioning, control and dynamic event capture, give your camera the advantage of some of the world's finest optics. Questar microscopes are available in several configurations, including our most recent development, the Step Zoom series which feature five parfocalized power changes, microprocessor control and computer access via an RS 422 port. From 15 centimeters to infinity, there is no better way to see. In an application requiring the positioning of a fiberoptic core, the variable magnification of the SZMIOO Microscope allows coarse and fine adjustment. Videographs taken from 20cm, fields of view of LSmm and OAmm. Give us a call or fax for a brochure and specifications on our Long-Distance Microscopes and Remote Measurement Systems. Questar Corporation Dept. N92 P.O. Box 59· New Hope, PA 18938· 215-862-5277 · FAX 215-862-0512 NASA Tech Briefs. September 1992 For More Information Circle No. 402 103 Power.:rool Adapter for T -handle Screws T-handle screws can be turned faster by a motor. John F. Kennedy Space Center, Florida A proposed adapter would enable the use of a pneumatic drill . electric drill. elec- tric screwdriver, or similar power tool to tighten or loosen T-handled screws. The operation would thus be done much faster than if the T-handles were turned manually. The adapter wOllld consist of a notched tube with a perpendicular rod welded to it (see figure). The user would insert the free end of the rod in the chuck of the power tool and slip the notched end of the tube over the screw handle. The user would then operate the tool to turn the handle to either tighten or loosen the screw. This work was done by Stephen R. Deloach of Lockheed Space Operations EA Made Easy. COSMOS/M FEA is easy to use, easy to buy and easy to expand. COSMOS/M FEA is powerful and solves complex problems - fast - on the PC or workstation. Still haven'j looked into It? Here are a few reasons why you should. 3D Automatic Meshing Obtaining an optimum mesh manually Is slow, Element plot of two sided impeller No problem. COSMOS/M solid elements have both translational and rotational degrees of freedom - similar to beams and shells - so you can mix these elements in your models without any difficulty. hard work. Let COSMOS/M do it for you! With a single command, the system places the nodes, creates the elements and generates the mesh. Also, its adaptive H- and P-Method generated mesh iteratively adapts Itself to a problem and solves it within specified error limits. Need to take a closer look? You can refine the mesh for a particular sectiori without remeshlng the entire model. so you save time and Increase accuracy. Comprehensive Element Ubrary Access an extensive library for creating true-to-life models. Can't connect beam, shell and solid elements with your current system? Automatic Error Convergence How do you know the solution is correct? With COSMOS/M there Is no doubt ... It calculates the error and refines the mesh locally until convergence to the specified error has been obtained. You can trust your results with COSMOS/M. Call Structural Research today to get your FREE 50-node version to try on your own problems. Prove to yourself what thousands already know. COSMOS/M FEA Is easy. 1661 Lincoln Blvd. Suite 200 Santa Monica, CA 90404 tel 310-452-2158 fax 310-399-6421 telex 705578 FEA from only $1550 Start with the modules you need today and add capabilities as you need them: 104 STATICS' DYNAMICS' ADVANCED DYNAMICS' HEAT TRANSFER' FLUID FLOW' ELECTROMAGNETICS • NONLINEAR' FATIGUE' CRASH DYNAMICS ' DESIGN OPTIMIZATION' SHELL AND SOLID OF REVOLUTION' FEATURES: H- and P-METHOD ADAPTIVE MESHING' SUBSTRUCTURING • COMPOSITE / SANDWICH' PLASTICITY. LARGE STRAIN . CREEP. ETC . • CRACK PROPAGATION' CAD AND FEA INTERFACES For More Information Circle No. 446 Co. for Kennedy Space Center. For fur- ther information. Circle 7 on the TSP Re- quest card. KSC-11514 Weld L ..... A VIEW A-A TOOL Chuck of ._-- Power Tool T-Handle : t r----, : I I ~---11 I ~---11 I I I L ___ _ Tool Is Tightened in Chuck Tool Is Slid Over T-Handle Tool in Operating Position on T-Handle OPERATION The Tubular Adapter is inserted in the chuck of the power tool and over the T-handle. NASA Tech Briefs, September 1992 Natural-Flow Wing Upper and lower surfaces are contoured independently to take advantage of natural flow. Langley Research Center, Hampton, Virginia A vast number of wing design schemes have been conceived to provide improved aerodynamic efficiency for wings with m0d- erate to high leading-edge sweeps. Ho.vever, previous designs were either point designs, which provided improvements in aerody· namic performances over small ranges of flight cordtions, or variable<:arTDer designs, which produced limited improvements in aerodynamic efficiencies over fairly broad ranges of flight conditions but resulted in additional complexities, increases in weight, and losses in usable volumes. ReQlon A B C D Geometry Posltlve Slope Posltlve Slope Negatlve Slope Negatlve Slope Pressure High Low Low High Drag High Low High Low o expanSion Region D Compression Region To overcome the disadvantages of the foregoing wing-design concepts, a novel scheme has been developed to contour the three-dimensional upper and lower surfaces of a wing independently of one another to take maximum advantage of the naturally occurring flow and the resultant distribution of pressure over a broad mach number and lift range. The naturaHIow wing- design concept increases the structural and volumetric efficiencies of swept lead· ing-edge wings by eliminating the need for variable-camber devices for imprCNed aero- dynamic performance over broad ranges of flight conditions. Standard Wing Natural·Flow Wing Experimental data and theoretical anal- ysis show that the flow and pressure load- ing over the upper surface of a swept wing at subsonic, transonic, and supersonic speeds tends to be conical about the apex of the wing. In particular, the flow over the upper surface under lifting conditions is conical in nature and can be character- ized by an expansion over the leading edge followed by a recompression to a more positive pressure as the flow moves in- board. However, typical wing shapes are conical about the tips of the wings. The intersection of the conical flow field and the geometry of a typical wing creates regions on the wing that are favorable and other regions on the wing that are unfavor- able with respect to considerations of drag. The unfavorable regions, which contribute to drag, are the inboard forward and the outboard aft regions. The other regions of the upper surface have pressure fields that combine favorably with the local surface geometry to reduce drag. The flow on the lower surface of the wing behaves quite differently at positive angles of attack. The flow over the lower surface is characterized by a nearly con- stant compressive loading. The pressure depends upon the angle of attack and on the streamwise curvature of the surface and is not very sensitive to the cross-sec- tion curvature of the wing. On the basis of these observations, the most beneficial ge- ometry of the lower surface would include NASA Tech Briefs , September 1992 The Natural- Flow design concept maxi- mizes the per- formances of both the upper and the lower surfaces of a wing. Region A B Geometry Posltlve Slope Negative Slope- Standard Wing as large an aft-facing area as possible. The natural-flow wing (see figure) is any three-dimensional swept-leading-edge wing in which the wing upper surface is contoured in a nearly conical fashion to align the local surface slopes more favor- ably with the resultant nearly conical pres- sure distribution. The lower surface of the wing is contoured to maximize the aft- facing area to provide a more efficient sur- face for the nearly constant pressure distribution to act. This approach to the design of a wing involves a scheme that contours the lower and upper surfaces at a given cross sec- tion to optimize the local cross-sectional slopes of the upper surface. To optimize the streamwise slopes of the upper and lower surfaces, each cross section is sheared vertically to create a reflexed low- er surface. The natural-flow wing design approach creates a wing that is nearly flat with mild cumber and minimal twist. The resultant wing has increased forward-facing area on the upper surface forward of the location of maximum thickness of the air- UPPER SURFACE Pressure High High Drag o Compression Region High Low Line of Maximum Thickness of Airfoil LOWER SURFACE foil , reduced aft-facing area on the upper surface aft of this location, and a reflexed lower surface (aft-facing area). The natural-flow concept results in a wing design that is efficient over a wide range of lift conditions. Wings designed for efficient supersonic flight should now be able to provide improved performance at lower speeds without resorting to heavy, complex, and expensive variable-camber devices. In addition to its aerospace ap- plications, this natural-flow concept could have far-reaching ramifications for both transportation and military systems. This work was done by Richard M. Wood and Steven X. S. Bauer of Langley Research Center: For further information, Circle 16 on the TSP Request Card. This invention is owned by NASA, and a patent application has been filed. in- quiries concerning nonexclusive or ex- clusive license for its commercial develolr ment should be addressed to the Patent Counsel, Langley Research Center [see page 24]. Refer to LAR-14281. 105 Highly parallel computing. Fermilab is tapping a new If there's one thing you can count on in science, it's that your data will increase exponentially but your funding won't. The scientists at Fermi ationaJ Accelerator Labora- tory (Fermilab) have encountered this problem in a very big way. The data Fermilab proces e for ubnuclear event reconstruction and modeling has reached 40 terabytes a year. And they've developed an innovative solution to meet their needs. Instead of relying on supercomputers, Fermilab ha di tributed a significant part of the workload to clustered IBM RISe ysternl6000"'M workstations. They've combined 108 of them, at late t count, in a LAN-connected Computer reconstructIOn of protonlantl·proton COUiSIOO at Fermllab source of power. proce sor farm. This farm gives FerrniLab a :full 3,000 MIPS that can be dedicated to a single parallel proces ing application. "The result," as Thoma ash, Head of Computing at Fermilab puts it, "is better science." At a fraction of the cost of using upercomputers. Many users are di covering the affordable, scalable power of clustered RISC Systeml6000 workstation . The ational Center for Supercomputing Applica- tion in Champaign, Illinois, for example, run uperscalar applications on a clu ter of even RISC Systeml6000 . High performanc and reliability are why they elected the RISC y tem/6000. BP Exploration (Alaska), Inc. is achieving supercomputer throughput for their re ervoir imulation applications by doing batch load balancing on a cluster of five RI C Systeml6000s. For their computers, oftware, sy tems integration and training in the use of batch clusters, they wor1 ed in alliance with IBM. We can help you, too - with consulting services, open systems inte- gration and Business Partner oftware. 1£ you'd like to make orne di coveries of your own abou t the power and economy of RISC System/6000 parallel processing, call ==-=_ IBM Technjcal Computing ystems §: : ~=-; at 1800 472-4966. ==-= ':' = a> IBM IS a registered trademark and RISC Systemi6000 Is a trademark of Internallonal Business Machines Coroorallon. C 1992 IBM Coro. xv, XVZ & emotions Complete systems for your motion require· ments For More Information Circle No. 396 THIN FILM COATINGS Help so lve your most demanding materials problems. Our contract research services develop coatings which are • Highly refractory • Wear resistant • Corrosion resistant • Custom designed for optical and electronic properties For aerospace applications in • Power and propulsion systems • Turbomachinery • Structural components • Sensors and actuators Production coating services available with in·house O.C. Tel: 1-800-798-3911 Fax: 1-800-798-5752 ~llli Midwest Research Technologies, Inc. 180 N. Bishops Way - Brookfield , WI 53005 Winner of eight SBIR awards. For More Information Circle No. 495 108 Are you reading someone else's copy? Get your own copy by filling in the qualification fo rm bound into this issue. Fixture for Testing Ball Bearings Under Radial Loads Variable test loads could be applied smoothly. Marshall Space Flight Center, Alabama A proposed fixture for mounting large ball bearings during tests would facilitate the application of variable, known radial loads. The fixture would prevent gross movement of the bearing in either radial or axial di rections. The fixture was designed for quick-turn- around tests at cryogenic temperatures to investigate wear in the ball bearings of the high-pressure·oxidizer turbopump of the main engine of the Space Shuttle. The fix- ture would be used to establish an exten· sive collection of data on bearings intend- ed for use at cryogenic temperatures. Similar fixtures could be designed to test bearings for other applications. A variable-load hydraulic cylinder would The Stubs of the Col- lar would rest in slots in the carrier ring . The ra- dial load would be ap- plied to the collar through Belleville spring washers . 57·mm Bearing To Be Tested Belleville ./ apply the load th rough Bellevi lle spring washers to a collar restrained by a car- rier ring (see figure). The load would be applied smoothly because the collar and outer race of the bearing wou ld flex in the carrier ring . The inner race of the bearing would be mounted on a shaft that would be rotated at the specified speed during application of the specified load. This work was done by John Gibson of Marshall Space Flight Center. No fur- ther documentation is available. Inquiries concerning rights for the com- mercial use of this invention should be ad- dressed to the Patent Counsel, Marshall Space Flight Center [see page 24]. Refer to MFS-28589. Load Applied by t Hydraulic Cylinder ./ / ~ Plug NASA Tech Briefs , September 1992 Water-Cooled Total.:remperature Probe A high-temperature probe has been tested in a superson ic wind tunnel. Langley Research Center, Hampton, Virginia Interest in the properties of hot super- son ic jet plumes has increased over the years, and this interest motivates the meas- urement of the mean flow properties of hot jets in cu rrent research. A knowledge of these mean flow properties aids the pre- diction of jet noise and may guide con- cepts for reduction of jet noise. A research effort was initiated to deter- mine whether a satisfactory design could be found to extend the present technology of measurement by uncooled probes into the high-temperature range by use of wa- ter-cooling techniques. Experiments were conducted in the NASA Langley Super- son ic Jet Noise Faci lity. Water-cooled su- personic total-pressure, static-pressure, and tota l-temperature probes were developed to study high-temperature jet plumes. The probes were supported in the flow by a supersonic wing. The experiments were conducted in three phases. The purpose of phase 1 was to develop and test the concept of water- cooled probes. In phase 2, the most effi- cient cooling design determined in phase 1 was used in the production and testing of the probes. Phase 3 was devoted to the observation and thermal analysis of the total-temperature probe. A water-cooled nozzle of 3.S4-in. (8.99- cm) exit diameter was used in the tests. It was designed for exit mach 2 at a total temperature of 2,000 ° F (1,093 0q. Water- cooled probes capable of operating under I 1 +, I I : I I Thermocouple Sheaths NASA Tech Briefs , September 1992 these conditions were tested. Data at the jet-exit planes and along the centerline of the jet were obtained for total temperatures of 900 OF (482 0q, 1,500 OF (816 0q, and 2,000 ° F (1 ,093 0c). The total-temperature probe tested up to 2,000 OF incorporated an annular cooling system up to, but not beyond, the thermocouple lead inside the probe (see figure). The lead extended into the test chamber to sense the temperature of the supersonic external flow. A portion of the thermocouple sheath formed a liquid-tight seal between the test chamber and the coolant chamber of the probe. The rate of transfer of heat across the ther- mocouple bead was greater when the coolant was turned on than wnen the coolant was turned off. The data obtained initially from the total temperature probe has an average error of 11 .2 percent, large- ly due to the presence of the water coolant. However, a heat transfer analysis was per- formed to account for the effect of the cooling system on the probe's thermal re- sponse, resulting in an average calculated total temperature error of 1.9 percent. The Annular Cooling Design proved the bet- ter of the two de- signs tested. The selected design of the total-temper- ature probe is both novel and significant. It shou ld be applicable in the development of jet engines and in research on fast flows of hot gases. This work was done by Nicholas T Lagen of George Washington University and Garland D Reece of Langley Re· search Center. Further information may be found in NASA TM-1G2612 [N9G-25645}, " Evaluation of Water Cooled Supersonic Temperature and Pressure Probes for Ap- plication to 200.0 OF Flows." Copies may be purchased [prepayment required) from the National Technical In- formation Service, Springfield, Virginia 22161, Telephone No. (70.3) 487-4650. Rush orders may be placed for an extra fee by calling (80.0.) 336-470.0. This invention is owned by NASA, and a patent application has been filed. In- quiries concerning nonexclusive or ex- clusive license for its commercial develop- ment should be addressed to the Patent Counsel, Langley Research Center [see page 24]. Refer to LAR-14435. PRECISION OPTICS STOCK AND CUSTOM - Spherical - Elliptical _ Parabolic - Front/Second Surface, Mirrors - Optical Flats - Gold Coated Mirrors - Beam Splitters - Laser Optics - Simple Lenses Free Reference Catalog For Your Technical Library - Achromats _ Prisms - Fiber Optics - Fresnel Lenses - Magnifiers - Polarizers - Filters OPTICAL INSTRUMENTS - Microscopes 196 Pages, Over 8000 Products Our new catalog describes one of the largest and most diversified lines in the nation of precision lenses, optics and optical instruments plus many hard-ta-find scientific and technical products used in science, industry and by researchers. TEL: 1-609-573-6250 FAX: 1-609-573-6295 - Reticles - Collimators - Comparators - Lasers For More Information Circle No. 461 109 Books and Reports These reports, studies, handbooks are avaIl- able from NASA as Technical Support Pack- ages (TSP's) when a Request Card number is cited; otherwise they are available from the National Technical Information Service. Absorption of Crushing Energy in Square Composite· Tubes Energy-absorbing capabilities of different materials scale divergently. A report describes an investigation of the crash-energy-absorbing capabilities of square-cross-section tubes made of two different matrix/fiber composite materials. The focus of the investigation was upon the geometric scalability of the energy-ab- sorbing characteristics. Crash-energy-absorbing structures in helicopters consist primarily of landing gear and subfloor beam structures. Con- siderable data have been developed on the crushing responses of circular tubes. A subfloor beam structure typically consist~ of an assemblage of flat and curved beam elements. Earlier research had indicated that the crushing responses of subfloor beams re- sembled those of their constituent ele- ments. The curved sections crushed in modes similar to those reported of round tubes, and the flat sections of beams crushed in modes similar to those of square-cross-section tubes. These results suggested that a better understanding of the crushing responses of square-cross- section tubes would provide deeper insight into the crushing responses and deSigns of subfloor beam structures. In these series of experiments, static crushing tests were conducted on graphite/ epoxy and Kevlar®/ epoxy tubes of square cross section to study the influence of the sizes and shapes of the specimens on the energy-absorption capabilities and scala- bility thereof. The static crushing tests were performed in a 540-kN capacity universal hydraulic testing machine. Load platens were set parallel to each other prior to in- itiation of the tests, and all tubes were compressed at the same rates. The loads and deflections of the crosshead were re- corded by an automatic data-acquisition system. Tests were stopped when the tubes had been crushed 5.08 cm, one-half of their original length. Three replicate tests were typically performed on each material and width of the cross section. Both the graphite/epoxy and Kevlar/ The dawn of a new age in low light level imaging. 110 GENIISYS. Offering a new beginning in low light level imaging. The technology and quality of our image intensifier system is what professionals around the world have come to expect from Dage-MTI. GENIISYS features high resolution, selectable 2/ 3" or 1" imaging format. automatic overload protection, dual gain presets and digital control. The wide dynamic range of the GENIISYS allows the user to go from brightfield to fluorescence without adjustment. For your demonstration, call 219-872-5514, or write for our literature to our corporate offices: 701 N. Roeske Ave. , Michigan City, IN 46360 U.S.A. FAX 219-872-5559 Oagpo!iYiJZlo,NC. precision video For More Information Circle No. 542 epoxy tubes crushed in a progressive and stable manner. The ratio between the width of the cross section and the thickness of the wall of the tube was determined to affect the energy·absorption capability sig· nificantly. As this ratio decreases, the en· ergy·absorption capability increases non· linearly. The energy-absorption capability of Kevlar/epoxy tubes was found to be geometrically scalable, but the energy-ab- sorption capability of graphite/epoxy was found not to be geometrically scalable. The results found in this study will be useful to anyone attempting to build energy-abo sorbing composite structures. This work was done by Gary L. Farley of the U.S. Army Aerostructures Direc· torate at Langley Research Center. Fur· ther information may be found in NASA TM-80987 (USA AVSCOM TM 87-8-3) [NBO- 735731 "Energy-Absorption Capability and Scalability of Square Cross Section Com- posite Tube SpeCimens." Copies may be purchased [prepayment required] from the National Technical In- formation Service, Springfield, Virginia 22161, Telephone No. (703) 487-4650. Rush orders may be placed for an extra fee by calling (800) 336-4700. LAR-14343 Schlieren PhotographiC Studies of Dynamic Stall Dynamic stall occurs at lower angles of attack at higher speeds. The report describes stroboscopic Schlieren photographic observations of flows of air around an airfoil oscillating sinusoidally about a fixed angle of attack. This is one in a continuing series of studies of the effects of compressibility on dy- namic stall - studies motivated by pre- vious observations that an airfoil can be made to produce greater lift by oscillating it through a range that includes angles of attack greater than the static stall angle but that compressibility significantly af- fects dynamic stall and can result in a net reduction in lift. The experiments were conducted in a wind tunnel on a National Advisory Com- mission for Aeronautics (NACA) 0012 air- foil of 7.5 cm chord oscillating sinusoidal- ly with an amplitude of 10° about a mean angle of attack of 10°. The photographs were taken looking along the span of the airfoil (perpendicular to the axis of the wind tunnel) . Free-stream mach numbers ranged from 0.15 to 0.45 in increments of 0.05. The reduced frequency of oscillation (defined as half the angular frequency of oscillation multiplied by the time required to traverse a distance equal to the chord NASA Tech Briefs , September 1992 at the free-stream speed) ranged from 0 to 0.15 in various increments. These mach numbers and reduced frequencies were chosen to encompass the conditions that occur on the retreating blades of helicopter rotors in forward flight. The results of the experiments are pre- sented as schlieren pictures at selected angles of attack as the airfoil undergoes a cycle of oscillation at a selected com- bination of mach number and reduced frequency. Some quantitative data extract- ed from the scnlieren pictures are also presented. These results indicate the following: • At all mach numbers and reduced fre- quencies used in the tests, a dynamic-stall vortex forms near the leading edge and is convected along the upper surface of the airfoil at approximately 0.3 times the free-stream speed. The origin of the vortex is not clear. • At all mach numbers, as the reduced fre- quency is increased, the initiation of the dynamic-stall vortex is delayed until the oscillation brings the airfoil to a higher an- gie of attack. • The effects of compressibility are signifi- cant at free-stream mach nuni:lers greater than 0.3: as the mach number increases beyond 0.3, dynamic stall occurs at de- creasing angles of attack. • No shocks are seen near the leading edge of the airfoil at the mach numbers and reduced frequencies used in the tests. This work was done by L. Carr of Ames Research Center and M. Chandrasekhara of the Naval Postgraduate School. Further information may be found in AIAA paper 89A-25019, "Flow Visualization Studies of the Mach Number Effects on the DynamiC Stall of an Oscillating Airfoil." Copies may be purchased [prepayment required] from AIM Technical Information Service Ubrary, 555 West 57th Street, New York, New York 10019, Telephone No. (212) 247-6500. ARC-12471 Developing a Navier- Stokes Algorithm for Supercomputers A computationally efficient scheme exploits parallel processing. A report discusses the development of an algorithm for the solution of the Navier- Stokes equations of flow on parallel-proces- sing supercomputers. "JYpically, the approach taken to solve a specific problem in flu id dy- namics depends on the problem. Here, the development involves the combination of various prior techniques to form an algorithm that can compute flows in a variety of com- plicated three-dimensional configurations. The subject matter should be of interest to NASA Tech Briefs, September 1992 Remote Viewing A tit's finest The most advanced Remote Viewing Instmments for observing or inspecting into inaccessible areas or hostile environments. BORESCOPES - More styles, sizes and operational features to satisfy all industrial applications. FIBERSCOPES -Largest selection of standard instruments with brighter and sharper images. 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FEATURES: integrated XY, 2D, and 3D plotting · contour line • color-flooded contours I<~' • vec to r fie ld s · s treamlines • light- ource shading · wire frames · interacti ve and menu driven • textldrawi ng tool • very large data sets • over 2000 variables per data point · multiple data ets · overl ay plots · up to 16 plots per page · fa t and easy to use · data . AlN''''- » ... U . ... . NT ••• O. manipulation · interpolation · tri angularization • macro .... Illit · stylesheets • batch mode · greek/math symbols · output Post- • .... Script, EPS, HPGL, and raster formats· very ).... flexibl e • educati onal discounts t·.. . for 386 PCs and UnixNMS ... wo rk s ta ti o ns • 60-day ... , ••.•• , .... ".. money-bac k guarantee ~ · crulfurFREEdemo Call 1-800-676-7568 Amtec Engineering, Inc. p.o. Box 3633, Bellevue WA 98009 206-827-3304 · Fax 206-827-3989 For More Information Circle No. 534 111 112 Use the Conap cure for your encapsulating and potting headaches. 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For complete specifications on CO NAP's EN-Series Elastomers, send for Selector Bulletin P-156. conap CONAP, INC. 1405 Buffalo St. , Olean, NY 14760 (716) 372-9650 Fax (716) 372-1594 For More Information Circle No. 389 researchers who are looking for ways to structure their problems for greater compu- tational efficiency. The research described in the report starts with testing of the feasibil ity of several ap- proaches to computation and the suitabili- ty of combinations of these awroaches. The algorithm that is developed includes an ex- plicit finite-difference numerical-integration scheme applicable to flows represented by a hierarchy of mathematical models rang- ing from Euler (inviscid) to full Navier -Stokes (viscous). This finite-difference scheme is adapted to parallel processing and is robust, but without further modification it would con- verge on solutions slowly. Convergence is therefore accelerated by the incorporation of multigrid schemes in which computation- al domains consist of coarse global grids with local finer subgrids embedded in them in regions defined by the physics of the flows. The characteristics of the flow in ques- tion are also used to determine which math- ematical model is appropriate for solution in each region, thereby reducing not only the number of grid points at which a solu- tion must be obtained, but also the amount of computation needed to obtain that solu- tion. Acceleration of the computation to the steady state is achieved by applying multi- ple-grid schemes on each of the subgrids, regardless of the particular model equations being solved. Because each such set of equations is put in explicit, finite difference form, which is easy to parallelize, one can exploit the vector- and parallel-processing capabilities of advanced supercomputers. A set of two-dimensional and three-di- mensional model problems that involve in- ternal flows of some complexity without re- quiring extensive expertise in the definition of geometry or the generation of grids is chosen for testing. Preliminary testing of each component of the algorithm is carried out in two dimensions, extended to three di- mensions, and then integrated into the three- dimensional solution scheme. Computed flows are presented, but the main focus is on performance; that is, on the goal that the computed flows remain invariant while the simulation time is reduced by various techni- ques under test. This v.ork v.as done by Julie M. Swisshelm of Ames Research Center. Further infor- mation may be found in NASA TM-102188 [N89-25959]. "Development of a Navier- Stokes Algorithm for Parallel-Processing Supercomputers.' , Copies may be purchased [prepayment required]from the National Technicallnfor- mation Service, Springfield, Virginia 22161, Telephone No. (703) 487-4650. Rush orders may be placed for an extra fee by calling (800) 336-4700. ARC-12637 NASA Tech Briefs, September 1992 You already know what a great problem-solving tool NASA Tech Briefs is. How it helps you: • Solve engineering problems • Apply practical innovations • Improve manufacturing processes • Discover new products . - • Save time and money Each issue grabs the attention of readers-like you-as it details innovative technologies available for transfer to the commercial sector. And, like you, many of our 200,000+ readers are key buying and specifying influences throughout those markets. They represent another important way that NASA Tech Briefs can help you and your company-as a sales and marketing tool. Advertising in I\U\Sl\TechBriefs also can help you: • Reach new markets for your products and services Our sales team makes every effort to tell marketing/advertising people about the importance of reaching our important readers, but we could use your help. Please fill in the coupon at the bottom of this ad and send it to us. It will tell us who at your company should receive our information package. We want you and your company to take advantage of all the ways NASA Tech Briefs can help: The technical and product information you enjoy as a reader as well as the new markets you can reach as an advertiser. In the meantime, remember. Nothing tells a story better than real dialog with someone you know. So, if you could take a few minutes out of your busy schedule, you can help us finish telling your marketing people the rest of the NASA Tech Briefs story. Call or send a memo to your advertising buyer. Tell them that we'll be sending some valuable media informa- tion to them. And let them know how important NASA Tech Briefs is to you-and how important it can be to your com- pany as a sales and marketing tool. Help us tell your marketing team why your company's ad should be part of the story our 200,000+ engineering and management sub- scribers will read in upcoming issues of I\U\Sl\TechBriefs. I think that readers like me in hundred of other companies could use our products and ervices. And to make sure they are reached by our advertising efforts, please rush more media information about NASA Tech Briefs to: Name/title: _______________ _ Oompany: _____________ __ _ Street ________________ _ City/state/zip: ______________ _ Phone/fax: _______________ _ Please clip and mail this completed coupon to us today, at: I\U\SI\ Tech Briefs 41 East 42nd Street, Suite 921 New York, NY 10017 (800) 944-NASA Machinery ~~ Direct-Interface, Fusible Heat Sink Heat is transferred directiy from warm water to ice. ,.----------------------, - - Ames Research Center, Moffett Field, California I f ~ A nonventing, regenerable, and self-con- tained heat sink (see Figure 1) absorbs heat in the melting of ice by direct con- tact with a forced flow of warm water. ([he warm water is the coolant fluid.) Such a heat sink, which was designed specifical- ly to cool an astronaut in a space suit, could be a component of a low-power port- able refrigerator intended to operate for a short time in a picnic or camp setting, for example. The heat sink consists of an elastic bladder, cast from a two-part polyurethane elastomer, that contains water and ice and that is penetrated by two identical sets of female and male connectors (see Figure 2). The bladder is filled with water until it is in slight tension. Upon freezing, the blad- der is stretched a little more by the expan- sion of the ice. When water in the cooling loop is initially pumped into the bladder, the flexible wall is separated from the ice, stretching the bladder even more. As the ice melts, the bladder relaxes, and when the pump stops (at the end of the cooling cycle), the bladder is again under slight tension. The heat sink can be disconnect- ed from the cooling loop at this point, its water refrozen, and the process repeated. The connectors are specially deSigned to prevent leaks, to be invulnerable to freez- ing of the water, and to be easily and quick- ly connectable and disconnectable. The two female portions of the connectors are embedded in the elastic wall of the heat sink, and water in them is frozen along with that in the rest of the heat sink. After the water in the heat sink has been completely frozen, the male portions of the connec- tors are inserted into the female halves, and the flow of warm water is initiated. At first, the warm water flows through the inlet male connector and into the emp- ty cavity of the inlet female connector. Be- cause the path is blocked by ice, the water returns through an annular passage in the inlet male connector and travels through a bypass tube to the outlet male connec- tor. Upon leaving the outlet male connec- tor, the water returns to the object to be cooled. The warm water quickly melts the ice in and around the female connectors. Once the ice around the female connec- tors has melted, the external bypass line is fully closed, so that some or all of the flow passes between the ice and the elastic bladder from inlet to outlet. 114 Figure 1. The Re- generable Heat Sink is shown at three stages of op- eration. Figure 2. The Con- nectors and Flows are shown in more detail at three stages of operation , begin- ning with the sec- ond stage shown in Figure 1. BLADDER FILLED WITH ICE, HEAT SINK NOT YEf CONNECTED TO FLOWING WATER t 1 ~ B Waler ~ =- BEFORE REGENERATION (ALL ICE MELTED) -~.--~ Female t ~ Connectors Ice '-::- =.J AFTER REGENERATION: FILLED WITH ICE Water I In , 'J '---I Bladder Male connector ' Male Connector Ice BEGINNING OF COOLING CYCLE BEGINNING OF COOLING CYCLE AT INLET I Inlet + Flow ICE MELTED AT TOP AROUND CON~ECTORS, FLOW THROUGH BLADDER BEGINNING The rate of transfer of heat to the melt- ing ice is controlled by adjusting the pro- portions of flow in the bladder and a by- pass tube. This adjustment is accomplished by use of a valve in the bypass tube. The female connector provides a jetting action NASA Tech Briefs, September 1992 that increases turbulence in the flow in the bladder; this, in turn, increases mixing dur- ing the later stages of melting to maintain proper heat-transfer rates and fully utilize the ice. A prototype of the heat-sink system was tested. Approximately 23 Ib (10.4 kg) of water was used, and the total heat capac- ity was 3,841 Btu (1,125 Wh). ln this system, a heat-transfer rate of at least 2,000 Btu/h (abo.ut 600 W) was maintained until (and for a short time after) all the ice had melted (approximately 1 h). This work was done by Curtis LDmax and Bruce Webbon of Ames Research Center. For further information, Circle 44 on the TSP Request Card. This invention is owned by NASA, and a patent application has been filed. In- quiries concerning nonexclusive or ex- clusive license for its commercial develop- ment should be addressed to the Patent Counsel, Ames Research Center [see page 24]. Refer to ARC-1192o. Robot Control Based on Spatial-Operator Algebra Complicated dynamical problems like that of two cooperating robot arms can be solved more easily. NASA's Jet Propulsion Laboratory, Pasadena, California A method for the mathematical model- ing and control of robotic manipulators is based on the spatial-operator algebra that has been developed in recent years and described in several previous articles in NASA Tech Briefs. The spatial-operator al- gebra provides a concise representation and a simple, high-level theoretical frame- work for the solution of manipulator kine- matical and dynamical problems that in- volve complicated temporal and spatial relationships; e.g., two multiple-link robot arms cooperating in the manipulation of an object. To recapitulate from the previous arti- cles: The elements of the spatial-operator algebra are linear operators, the domain and range spaces of which consist of forces, torques, velocities, and accelera- tions. The operators are called "spatial operators" because they show how the forces, torques, velocities, and accelera- tions propagate through space along a manipulator arm from one rigid link to the next (see figure). The operators are also implicitly equivalent to tip-to-base or base- to-tip recursions, which can easily be turned into algorithms by projection onto appropriate coordinate frames Recursive algorithms can be derived This Graph Represents Two Multiple-link Robot Arms: the nodes represent links, while the edges represent joints. Spatial operators show how dynamics and kine- matics propagate in the causal (tip-to-base) and anticausal (base-to-ti p) di rections. NASA Tech Briefs, September 1992 immediately from abstract spatial-operator expressions by inspection. 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Pneuma -Seal is particularly suitable for: Large enclosures where it is uneconomical to machine the entire sealing surface Uneven fabrications where traditional compression gaskets or latches are ineffective Horizontal or vertical sliding doors or covers that would tend to drag on and abrade conventional sea1s Hinged doors where flush thresholds are required 1YJ>ica1 applications include: Processing equipment: chemical, food, textile, pharmaceu· ticals, dryers, ovens and where rapid sealing and unsealing are required PoUution control: sound attenuation, hopper seals Laboratory facUities: test equipment, clean rooms Transportation: military vehicles, aircraft, shipboard, mass transit doors and hatches Construction: special purpose doors, flood protection Pneuma-Seal is available in a wide range of profiles, with fabric reinforcing where applicable, and in a variety of rubber and silicone compounds to meet harsh environmental conditions. Pneuma·Sea1 is furnished complete, ready to install as continuous loops, strips, rectangles, or other shapes to your specified dimen lonal requirements. To obtain a complimentary copy of our designer's handbook, engineering assistance or to have a Presray representative contact you, please call us at any of the following telephone numbers: (914) 855-1220 Telex: 646720 FAX: (914) 855-1139 West Coast: (714) 751-2993 Pres ray Corporation 159 Charles Colman Boulevard, Pawling, NY 12564 YO MAY AlSO CONTACT US BY CJRCUNG THE RESPONSE NUMBER INDICATED BELOW. For More Information Circle No. 602 115 mentation of specific algorithms to com- pute the solution is greatly simplified. Such economy of thought and representation has led to the development of a very sim- ple program with which the user can inter- act to execute the maneuvers of cooper- ating robot arms with simple high-level commands like " lift," "squeeze," "grasp;' " transfer," and " insert." The control method has been imple- mented in an object-oriented software library in the Ada language that enables programming and execution of computa- tions for the control and coordination of the two cooperating arms. Problems that can be addressed by the software include the generation of trajectories for transfers of objects, automated allocation of work to each arm during execution of a task, and hybrid force/position control to enable the arms to apply a prescribed internal force to an object while transferring it. The complexity of the computations is made completely transparent to the user be- cause the spatial-operator algebra allows a very abstract description of the manipu- lation problem and of its corresponding solution. This control method will enable the au- tomated execution of a wide range of new manipulator tasks that cannot be performed easily with one robot arm. Examples of such tasks include handling and manipula- tion of cumbersome, oddly shaped and ex- tended objects; the handoff of objects from one arm to the other; handling of flexible Sorbent-Bed Crop-Drying System Some water and heat would be removed from recirculated air. Marshall Space Flight Center, Alabama A proposed aeration system would help to reduce spoilage of stored grain or other crop stored in bulk. The system would re- move some of the moisture and some of the heat from air flowing into the storage vessel and would help to maintain a more nearly uniform temperature throughout the bin so that pockets of high moisture would not form or migrate. The system would maintain the temperature and relative hu- midity in the vessel near or below ideal set- tings of 50 ° F (10 0c) and 60 percent, re- spectively, so that the growth of mold is suppressed and insects remain dormant or die. The system would be suitable for such storage vessels as grain bins and shipping barges. Storage Bin objects like long booms or large panels; assembly of structures or subassemblies from simple structural elements; and sim- ultaneous manipulation of two or more 0b- jects in a workspace. This work was done by Guillermo Rodriguez, Kenneth K. Kreutz, and Abhinandan Jain of Caltech for NASA's Jet Propulsion Laboratory. For further information, Circle 17 on the TSP Request Card. This invention is owned by NASA, and a patent application has been filed. In- quiries concerning nonexclusive or ex- clusive license for its commercial develorr ment should be addressed to the Patent Counsel, NASA Resident Office-JPL [see page 24]. Refer to NPO-17918 Air Returns fl-!.0 Out~e _ ... r- '-f I I Legend Damper Blower Air Filter Moisture Sensor Temperature Sensor L ___ __ Outside Air Enters The system (see figure) would include a heat exchanger and a regenerable sor- bent bed of zeolite or other suitable ma- terial. A blower would force air into the bin at its bottom, out of the bin at its top, and through a filter, which would prevent grain dust from reaching and clogging the sor- bent bed. The filtered air would flow through the sorbent, which would remove moisture from the air. A damper would send part of the airflow through a bypass as neces- sary to regulate the net moisture content of the overall sorbent-bed and bypass flows. Air Would Circulate through the bin , sorbent bed, and heat exchanger. Outside air would cool the circulating air in the heat exchanger. The dried air would then flow through and be cooled by the heat exchanger, which would transfer heat to the outside air. A bypass would be used here also, to regulate the net temperature of the com· bined bypass and heat-exchanger airflows. The heat exchanger would remove the heat that would be added in the sorbent bed and would keep the temperature of air in the bin close to that of the outside air. Finally, the dried, cooled air would re- enter the bin through the blower. 116 The sorbent would be regenerated from time to time by pumping hot air through it. The hot air could come from the out- side in hot weather, from a small electric heater, and/or from the heat exchanger. The system would include a controller connected to sensors that would measure the temperature and humidity at three points: just downstream of the sorbent bed, just downstream of the heat exchanger, and in the bin. It would adjust the dampers in the bypass loops to obtain the requisite temperature and humidity in the bin. This work was done by Barry C. Roberts of Marshall Space Flight Center. For fur- ther information, Circle 79 on the TSP Re- quest Card. Inquiries concerning right:. for the com- mercial use of this invention should be ad- dressed to the Patent Counsel, Marshall Space Flight Center [see page 24}.Refer to MFS-28567. NASA Tech Briefs, September 1992 Manual Override for "J Electromechanical Latch ... A manual clutch and crank are used when a primary drive train fails. Goddard Space Flight Center, Greenbelt, Maryland An override mechanism enables a user to operate an electromechanical latching mechanism manually if the pri- mary mechanism should fail. The override feature can be used to latch and unlatch large, heavy objects from a fixed support structure. The primary, electrically operated latching mechanism includes a worm gear in a drive train . The override feature is needed because if the primary mechanism fails , the object to be latched 'Or unlatched could be stuck in an unsafe, partially latched or partially unlatched position because the worm gear cannot be backdriven . The user operates a clutch on the manual backup system to disengage the primary system (see figure) . The user then cranks a four-bar linkage that retracts or engages pins on the deployable component into pin receivers on the fixed sup- port structure, a function that would ordinarily be done by the electrically driven mechanism. The deployable component is securely latched when the linkage is in an overcenter position. This work was done by Richard Scott of Goddard Space Flight Center. For further information, Circle 90 on the TSP Request Card. GSC-13383 REM (Release/Engage Mechanism) Adapter REM (Rei easel Engage Mechanism) A!1f'pter ENGAGED (STOWED) CONFIGURATION REM (ReleaselEngage Mechanism) Adap ler Manual Pin Receivers DISENGAGED (DEPLOYED) CONAGURATION The Manually Operated Release/Engage Mechanism (REM) moves pin receivers to confine pins on an object to be held. A clutch disengages the electrically driven latch that is normally used. NASA Tech Briefs, September 1992 TOTALABTM THERMAL ANALYSIS. Precision is more aHordable than ever. Harrop's TOTALAB System is proof that thermal ;m~ly~is instrumentation - DTA. TGA, and dila- tometers - need not be expensive to be effective. TOTALAB is easy to use and designed for years of reliable operation. Analysis modules are available up to 1600oG. For data storage and more sophis- ticated analysis the new GYBER 702 digital data acquisition system is unique in its use of standard spreadsheet software. Or check out Harrop's tradi- tional analog instrumentation. Either way, TOTALAB is the way to go for affordable - and effective - thermal analysis. For more information, contact Harrop Industries, Inc., 3470 E. Fifth Ave., Columbus, Ohio 43219-1797. Phone: 614/231-3621. TELEX: 810 482 1645 FAX: 614/235-3699. ~~~,!JP ~ FIRE OUR IMAG/IIATIOII! For More Information Circle No. 506 11 7 iiEI Fabrication Technology ~Cheaper Custom Shielding Cups for Arc Welding Cups are molded from hobby ceramic. Marshall Space Flight Center, Alabama A new way of making special-purpose shielding cups for gas/tungsten arc weld- ing greatly reduces the cost. Special-pur- pose cups have to be made when the geometry of a workpiece does not accom- modate a standard cup. Previously, special cups were machined from lava rock - a costly procedure. In the new method, a pattern of the cup is first machined in plastic: A plaster-of- paris mold is made of the pattern. Liquid ceramic is poured into the mold. After 10 minutes, the still-liquid ceramic in the mid- dle of the mold is poured away, leaving a ceramic shell adhering to the inner wall of the mold. The solid shell is allowed to harden further in the mold for 2 to 4 h. The halves of the mold are separated, and the ceramic casting is removed and trimmed to size. The casting thus formed is baked for 1 h at 1,950 OF (1,066 0c). After cooling, the cup is ready for installa- tion on a welding torch (see figure). The liquid ceramic can be purchased in hobby shops for ~$4/gal (~ $1/L) (1990 prices). The overall cost of a molded ce- ramic cup is about 90 percent less than that of a cup machined from lava rock. This work was done by Gene E. Morgan of Rockvvel/ International Corp. for Mar· shall Space Flight Center. No further documentation is available. MFS-29815 The Molded Ceram ic Cup is made by a simple procedure , using inexpensive mate- rials. The cup is shaped to fit a specific weld geometry. ~~Compact Through·the~orch Vision System A welding torch and its optical system have been redesigned. Marshall Space Flight Center, Alabama Changes in the design of a gas/tungsten- arc welding torch equipped with a through- the-torch vision system make the torch as- sembly smaller and more resistant to the welding environment. In addition, the vi- sion subsystem produces an image of 118 higher quality, the flow of gas is enhanced, and parts can be replaced more quickly and easily. The torch houses a coaxial series of lenses and other optical components (see figure). It provides an overhead view of the weld joint and weld puddle that is used for real-time control of the welding process. This version of the torch was designed around a miniature high-resolution video camera. The resulting smaller size enables the torch to weld joints that were formerly inaccessible. The torch now includes a replaceable optical cell that contains lenses that focus the image onto the array of photodetec- tors in the camera. lWo such cells are avail- NASA Tech Briefs, September 1992 _---.,~ Camera Array of Photodetectors Focusing Cell Light Valve Aperture Disk Collet Subassembly Gas Cup '-______ Electrode Stacked Optical Elements give the video camera a clear view of the weld area im- mediately surrounding the electrode tip. The use of a miniature camera and other compact components reduced the size of the torch and the vision system. able, providing !'NO different focusing ranges: The cell in the torch can be changed to obtain the proper focal length for use with a shorter or a longer gas cup. The outer surface of the body of the focusing cell is textured with axial serrations to facilitate adjustment, and the housing of the focus- ing cell includes three circumferential slots that provide access for the adjustment. A lead lanthanum zirconate titanate elec- tro-opticallight valve regulates the amount of light that reaches the camera to pre- vent overexposure during pulsed welding. A pulsed high-voltage control signal is ap- plied to the light valve through a miniature coaxial connector. A compliant mounting ring compresses the light valve against the high-voltage contact pads. The number of spokes that support the collet that holds the welding electrode was reduced from six to four to reduce block- age of the image area. The spokes also carry current to the welding electrode. The collet was made shorter and narrow- er to reduce blockage further. The design of the collet was modified so that the elec- trode can be released and replaced more easily: It is no longer necessary to remove the collet subassembly to replace the elec- trode. A special tool was designed to fa- cilitate installation and removal of the elec- trode. The tool aligns itself and sets the NASA Tech Briefs, September 1992 distance through which the electrode pro- trudes from the gas cup. A gas-diffusing ring with larger pores - 40 p.m instead of 20 p.m - gives wider coverage of the weld. An optical band-pass filter was custom-made to block most of the unwanted light from the arc plasma but lets enough light from the weld enter the vision system. A relay lens transmits light to the filter and keeps the welding gas out of the rest of the optics. An aperture disk sets the depth of field . Aperture disks of various sizes are interchangeable. They are blackened, and the surface facing the weld is angled to reduce reflections of stray light. The internal surfaces of the torch are also blackened. The torch is jOined to the camera by a special rotating C-mount adapter. The adapter makes it possible to align the camera squarely with the direction of the weld joint and thereby ensures that the im- age of the jOint is oriented horizontally on the video screen of the welding monitor. This work was done by Jeffrey L. Gilbert and David A. Gutow of Rockwelllnterna- tiona I Corp. for Marshall Space Flight Center. For further information, Circle 108 on the TSP Request Card. Inquiries concerning rights for the com- mercial use of this invention should be ad- dressed to the Patent Counsel, Marshall Space Flight Center [see page 24}.Refer to MFS-29811. Ir. keJlex - - - RADIOGRAPHY Radiography is just one of the many applications possible with Kevex X-RAY's patented portable X-ray source, the PXS_ The PXS can create new market opportunities for your products. The design eliminates the bulk associated with conventional X-ray systems allowing your products to be portable, lightweight and compact. Some new products to date include: • A portable real-time imaging system for detection of tampered products in the field • A radically different altimeter for the next generation of aircraft • An on-line thickness gauge used in 100°C environments • A compact X-ray fluorescence system • A tabletop double crystal diffractometer • An airborne meteorological device for measuring particle distribution All possible because of the self-contained compact X-ray energy source, the PXS. Kevex X-RAY integrated a miniature X-ray tube and a high voltage power supply into one compact, 5 lb. package. Operational from a 12 volt DC battery, this highly regulated, highly stable source has all the high voltage components molded internally. As a result there are no high voltage cables or connectors to work around. Designed, manufactured, and sold only by Kevex X-RAY. Call or write Kevex X-RAY today for information Qn our complete line of portable sources including the 10 micron focal spot PXS. keJlex X-lUl' P.O. Box 66860 Scotts Valley, CA 95066 408-438-5940 o A va Inst,uments Group Compeny For More Information Circle No. 646 119 Curing a Large Composite Cylinder Without an Autoclave A wrapped tube would provide even pressure. NASA's Jet Propulsion Laboratory, Pasadena, California A proposed technique would provide for the application of heat and pressure to cure a fiber-wound composite cylinder (e.g., a pressure vessel) too large to fit in an auto- clave. The uncured cylinder, still on its wind- ing mandrel, would be enclosed in a blan- ket, and a flattened tube would be helically wrapped on the blanket (see figure). The interior of the tube would be pres- surized, causing the tube to compress the blanket. In turn, the blanket would help to distribute the pressure more nearly uni- formly over the surface of the cylinder. The pressure would expel gas bubbles from the composite material. Meanwhile, heat would be applied by conventional methods. This WJrk was done by Robert E. Frazer of Caltech for NASA's Jet Propulsion Laboratory. For further information, Cir- cle 84 on the TSP Request Card. NPO-18195 A Tube Wound Around a Compos- ite Cylinder would apply pressure dur- ing curing. The blan- ket would help to dis- tribute pressure from the tube over the cyl- inder. MAGNIFIED MERIDIONAL CROSS SECTION SHOWING WRAPPED TUBE AND BLANKET 120 offer something else: OIie-Stop shoppiflo. Tanks that rely on our experience making the world's best composite-metal vessels, iniegtated with our WINTEC PMOs and fitters, renowned for their quality and precision welding. Brunswick's the one source that can help your program take off. Today. For 1lIOI'I iIItormatlon, call Or write: Brunswick Defense I Space Products Business DevelQpment 3333 H8rbor Blvd. Costa Mesa, CA 92628 (714)546-8030 FAX (714)546-1404 For More Information Circle No. 420 A UNIT OF THE MUIIISWIICK ra::HIICU GIfOUI' C> 1992 Brunswick Corporation NASA Tech Briefs, September 1992 Long-Wearing Wire Guide for Welding Torch A hard insert protects the relatively soft metal guide tube. Marshall Space Flight Center, Alabama An insert for the wire-guide tube on a tungsten/inert-gas welding apparatus ex- tends the life of the guide tube and in- creases the accuracy of the weld. Ordinar- ily, a wire guide, which is made of copper or brass tube, wears quickly as the filler wire is fed through it. As it wears, the cir- cular orifice at the tip becomes elliptical or egg shaped. The filler wire then' wanders in the orifice, and its position in the weld puddle is hard to control. The insert, which is made from drill rod, then hardened, wears only negligibly, and the orifice remains circular. The inner (up- per in the figure) end of the insert is cham- fered to center the tip of the filler wire when the wire is first fed into the guide tube. The copper or brass base material of the tube is formed around the end of the insmt to hold it securely. This work was done by David A. Gutow, Richard K. Burley, Jeffrey L. Gi/bert, and Irving Fogel of Rockwell International Corp. for Marshall Space Flight Center. No further documentation is avai/able. MFS-29829 The Hardened Insert resists wear by slid- ing tungsten wire. The chamfer guides the wire into the insert. Motion of Wire ~ Guide Tube Base Material of Guide Formed Over End of insert To Hold Insert in Place Preformed Superconductive Devices Ceramic superconductors are subjected to high-temperature processing before mounting. ~~ Langley Research Center, Hampton, Virginia A process forms high-temperature su- perconductors into such practical elec- trical components as connectors, coils, and conductors (see figure). The com- ponents are based on YBa2Cu30 7 _ x ce- ramics, which have superconducting tran· sition temperatures of about 95 K and can thus be cooled with liquid nitrogen instead of the more costly liquid helium. Until now, it has been difficult to make working devices of superconductive ce- ramics because of the brittleness of these materials. However, brittleness is no ob- stacle to the improved process, in which the material is preformed into the requisite shape before it is heated to turn it into the ceramic. The process consists of these eight basic steps: NASA Tech Briefs, September 1992 1. Fbwders of yttrium oxide, barium car- bonate, and copper oxide are mixed with polymer binder and cast as a thick film to form a tape. 2. While the tape is still flexible, it is stamped, cut, or otherwise formed into strips of the desired sizes and shapes. 3. The parts thus formed are left flat or formed, as required, into cylinders, rings, or other shapes. Strips can be stacked in layers, if necessary. 4. The parts are sintered to turn them into rigid pieces of superconductive ceramic. 5. Electrodes are applied. 6. The parts are mounted on plates, rods, disks, or other rigid substrates for sup- port and isolation from stress. 7 .. Lead wires are soldered to the electrodes. For More Information Circle No. 523 121 8. The part and substrate are encapsulat- ed to protect the ceramic film from the environment. Because sintering takes place before the ceramic is mounted on the substrate, the substrate material need not be resis- tant to high temperatures. In addition, the sintering conditions can be optimized for the ceramic material, without regard for the substrate. An abundance of oxygen can be provided during sintering to obtain maximum superconductivity. Sintering be- fore mounting also eliminates the problem that would otherwise be posed by shrink- age. The substrate can be sized to match the final dimensions of the ceramic. Substrates can be made of glass-fiber- reinforced circuit-board material, for exam- ple. This substrate material reduces the leakage of heat into the ceramic, unlike the silver or copper substrates used in mak- ing sintered-in-place superconducting ceramics. Each ceramic superconductive part can be tested before it is assembled on the substrate. This prevents the waste of time and material in the encapsulation of faul- ty parts and increases reliability and repra- ducibility of the finished superconducting devices. The process has been used to make a grounding link 6 in. (15.2 cm) long for an infrared detector. The ceramic supercon- ductor reduces noise and increases the signal-ta-noise ratio. it reduces the transfer of heat from the detector preamplifiers at J I cr :5 ':::) TEMPERATURE (K) , 100 120 140 160 180~ 220 240- 260 - 280"'" 300 Sintered Ceramic Preforms in a variety of shapes can be mounted on printed-circu it- board substrates. A plot of the resistance-versus-temperature behavior of the ceramic appears in the background; the resistance drops sharply to zero at about 95 K. 90 K to the detector at 4 K. Also, because it can be cooled with liquid nitrogen, it con- serves liquid helium for the sensor, thereby increaSing the operating life of the sensor. This 'MJrk was done by Gene H. Haertling of Clemson University and John D. Buckley of Langley Research Center. For further information, Circle 3 on the TSP Request Card. Inquiries concerning rights for the com- mercial use of this invention should be ad- dressed to the Patent Counsel, Langley Research Center [see page 24]. Refer to LAR-14395. !J Floating Ring-Groove Lapper A tool refinishes a warped seal groove. Marshall Space Flight Center, Alabama A tool fits in an out-of-round seal groove and laps it to a fine finish without binding. The tool (see figure) is designed to fit the specific groove to be lapped. It includes floating lapping pieces that ride freely in the groove despite its out-of-roundness. The lapping pieces are curved to match the nominal diameter of the groove. They are held by bolts in radial slots in a disk. The disk is placed over the groove so that the pieces rest in the groove. The disk is centered approximately, and one of the lapping pieces tightened in place in its slot so that it does not move relative to the disk. The two remaining lapping pieces are left free to swivel. The disk is then rotated to lap the groove. This work was done by Robert L. Williams, Sr. , Robert L. Williams, Jr., and Timothy L. Chase of Rockvvell International Corp. for Marshall Space Flight Center. For further information, Circle 62 on the TSP Request Card. MFS-29749 Lapping Pieces Fit in a warped groove. Allow- ing two pieces to slide and swivel in their slots prevents the lapping tool from binding. 122 t$SSr$$$$$G;OOv~\~$$$$$$)%s$$$SSSSSS$$$$$~LapPing ' .______ Be Lapped , Piece ~~ 4 + D SECTION A-A NASA Tech Briefs, September 1992 Guide for Assembly of Electrical Connector Mating cylinders align mating parts to prevent bending of connector pins. Marshall Space Flight Center, Alabama An assembly guide aligns the two mating parts of an electrical connector to prevent the bending of connector pins. The guide consists of two closely fitt ing cyl indrical sleeves, one sleeve sliding within the other (see figure). Each sleeve is split longitu- OUTER SLEEVE INNER SLEEVE Part of Outer Sleeve Grips Alignment Groove ASSEMBLY Part of Connector (Potted on End of Cable) Mating Sleeves are designed to align the centerlines of the two parts of a connec- tor. The segments of the inner and outer sleeves are held together by spring clips. The inner sleeve grips the part of the con- nector that is attached to a cable. The outer sleeve grips an alignment groove of the other part of the connector. NASA Tech Briefs, September 1992 dinally and can be separated into identical segments. A pair of spring clips on each sleeve holds the segments together. The inner sleeve grips the part of the connector that is potted onto the end of a cable. The outer sleeve grips the other part of the connector via an alignment groove on the connector called the "in- dicator groove." When the two sleeves are engaged, the two parts of the connector are concentric. In this condition , the two parts of the connector halves are self- piloting. The part of the connector on the cable is rotated to engage a keying device on the other part of the connector. The connector nut is then threaded about two turns into engagement to pre- vent the two parts of the connector from separating when the assembly guide is removed. Finally, the spring cl ips are ex- DO YOU KNOW HOW YOUR PRODUCT IS REALLY BEING USED? How do you get that information? W h n you want in-service data and analy:-,i:-, [a:-,[ and easy, oMa[ ha the solution for you with our family of Field Computer y terns! For about 1000 a channel, you get the information you want, and you also get SoMat support. You can count on it! One cu tomer says "If more companies u 'ere as cooperatil'e after the equipment was purchased like SoMat, my job would be a lot easier . .. " Other customers comment: "SoMat really listens and devel- ops what the customers ask/or ., ''Now u'e have extensil'e field testing, not just with our in-house machine . We have an edge over our competitors." ''Pirst rate in evel)' respect." S OMat II software is at d1e head of the family of Field Computer ystems and run d1e entire Field Computer family from calibration and test setup, to display immediately after the test, to analysis of the information collected. Strains, torques, loads, accelerations, pressures, temperature , voltages, Hall Effect sen ing, encoders, frequencies - If you need f ield testing capability, call us at (217) 328-5359. SoMat - when timely results matter For More Information Circle No. 419 123 tracted, and the cylindrical sleeves are removed from the aligned, mated parts of the connector. This work was done by Elroy C. Williams of Thiokol Corp. for Marshall Space Right Center. For further information, Cir- cle 28 on the TSP Request Card. Inquiries concerning rights for the com- mercial use of this invention should be ad- dressed to the Patent Counsel, Marshall Space Flight Center [see page 24]. Refer to MFS-28582. Electroforming Repair of Adjacent Unconnected Layers A thin conductive coat between the layers acts as a weak fracture surface. Marshall Space Flight Center, Alabama A procedure has been devised to im- prove the repair of a hole through a nickel- alloy layer and a nickel layer that are parts of a larger structure and that are separated by a thin gap. The procedure is a sequence complex problem Here's all the "tooling up" you need to build strong enclosures to your own specs: An ordinary mallet and a few wrenches. AMCO's 6061-T6 High Strength Aluminum Framing System does the rest. You get extraordinarily strong enclosures, custom-made for your application, without long delays. We can supply the pieces or build the whole enclosure. The system consists of extruded aluminum tubing, comer castings, locking pieces,non-locking clips (for prototyping), and accessories_ A relatively concise selection of standard pieces covers a very broad range of applications. of steps that involve established tech- niques of electroforming and the associat- ed established techniques of grinding, fill- ing, and masking. The two major distin- guishing features of the repair are a wax- Build enclosures from 8" to 20' in any 90° plane. Combine big compartments and small ones in any combination you need. Amazingly strong. Our comer locking methods actually surpass the strength of welding. This system has withstood some very tough applications -like NASA Airborne, shipboard, ground support firing systems enclosures and missile launch systems. Phone for Catalog #203 Call 1-800-833-3156 In illinois, 1-708-671-6670 AMCO Engineering Co. 3801 N. Rose Street Schiller Park, IL 60176-2190 AMCO's Heavy Duty Aluminum Structural System. 124 See us at ASIS San Antonio, TX 9/14-9/16 Booth #844-846 For More Information Circle No. 500 filled separation channel around the edge of the hole and a conductive coat that serves as a weak fracture layer between the repaired layers. The figure illustrates an example of the procedure - a simplified version based Jacket Liner Underlying Layer of Copper STRUCTURE BEFORE AND AFTER HOLE IS CUT IN JACKET AND LINER Channel Filled With Wax GRIND CHANNEL, BLEND CONTOUR, FILL WITH WAX (STEPS 1 AND 2) Electrodeposited Nickel (Restored I"r"l....,...., .... Part of Liner) RESTORE LINER BY ELECTRODEPOSITION (STEPS 3 AND 4) APPLY CONDUCTIVE COAT (STEPS 5 AND 6) Conductive Coat Remains as Weak Fracture Layer ESTORE JACKET (TO THICKNESS GREATER THAN ORIGINAL) BY ELECTRODEPOSITION The Hole in the Liner and Jacket is repaired in a sequence of grinding, masking, filling, and electroforming steps. NASA Tech Briefs, September 1992 on the original application. In this case, the nickel-alloy layer is called the "jacket," and the other, purer-nickel layer is called the "liner" and is attached by electrodeposi- tion to an underlying layer of copper. The hole to be repaired penetrates both nickel- containing layers down to the surface of the copper. The procedure can be sum- marized as follows (omitting some inter- mediate and incidental steps that involve grinding and inspection): 1. Grind the edges of the hole to (a) blend the surface contours of the jacket and liner smoothly with that of the copper, and (b) add a separation channel that straddles the gap and runs along the en- tire circumference. 2. Fill the channel with wax, and blend the wax to the surface contour. 3. Mask off the exposed liner and copper to prevent plating on them, then plate nickel on the jacket to a thickness of about 0.01 in. (0.25 mm). 4. Unmask the liner and copper, mask the jacket, and plate nickel on the exposed liner and copper up to approximately the thickness of the liner. In essence, this ster restores the missing portion of the liner 5. Unmask the jacket and remove the wax from the channel. Fill the channel with putty or silver/facsimile mixture, and blend this filling flush with the surface contour. 6. Wet-sand the nickel surfaces to prepare them for plating, then apply a layer of silver-filled conductive coating material 0.001 to 0.025 in. (0.025 to 0.64 mm) thick to the surfaces of the channel fill- ing and of the restored portion of the liner that was deposited in step 4. This conduc- tive coat will serve as the weak fracture layer and will occupy the gap between the liner and jacket in the repaired area. 7. Plate nickel on the conductive coat and on the adjacent area of the jacket to re- store the jacket to the desired thickness. This work was done by Daniel J. Burbach and James F. Herkenhoff of Rockvvellinternational Corp. for Marshall Space Flight Center. For further informa- tion, Circle 30 on the TSP Request Card. MFS-29828 Ambient~emperature Sputtering of Composite Oxide Films A multiple-target, sequential-sputter-deposition technique is compatible with low-temperature microelectronic processing. NASA's Jet Propulsion Laboratory, Pasadena, California A technique for deposition of homo- geneous films of multicomponent oxides, such as ferroelectric lead-zirconate-titanate (PZT), on substrates held at ambient tem- perature has been developed. This tech- nique is based on sequential sputter depo- sition of the individual metal components, as alternating ultra-thin layers, from multi- ple targets in a suitable reactive ambient, followed by a moderate-temperature an- neal to obtain the desired crystal structure as a single phase. Deposition is carried out on substrates held on a rotating holder (see Figure 1), and the dc magnetron sputtering targets are powered to different levels, which allows accurate control of the individual consti- tuent flux reaching the substrates, the most critical parameter in achieving stoichiometric deposits. This ensures an optimal solid-state reaction among the constituents during the subsequent an- nealing/sintering step, leading to the for- mation of a homogeneous, single-phase deposit. In addition to the rate of simultaneous sputtering from each target optimized for a given geometry of the deposition cham- ber, the angular window for deposition of each constituent material is governed by the respective angular-deposition aperture and size of the target. The revolutions per minute (rpm) determine the time window for each constituent deposition. The near homogeneous mixing of the constituents during deposition, therefore, eliminates the need for substrate heating in vacuum. Individual control of each metal is ob- tained down to even a fraction of a mono- layer thickness in individual layers by se- lecting the sputtering powers and the substrate-rotation rate. In the case of PZT films, for example, a subsequent post-de- NASA Tech Briefs, September 1992 position anneal treatment of as low as 500 DC is sufficient to initiate the crystal- lization within the deposited multicompo- nent film, leading to the formation of fer- roelectric/piezoelectric films. This separation of the deposition proc- ess (at ambient temperature) in vacuum from the sintering step for crystallization in an open-air furnace makes this tech- nique readily compatible to low-temper- ature microelectronic-fabrication tech- niques, such as conventional patterning by photolithography using polymeric pho- toresists. This technique is ideally suited for deposition of a variety of other multi- component materials, including oxides and nitrides. In addition to the deposition parameters governing the rates, the angle of incidence of the sputter deposit is also a very critical parameter in determining the morphology and physical characteristics of the films. For example, when all angles of deposi- tion are allowed, the resulting film can be Substrates Are Ro- tated over sputter- ing targets of lead, zirconium, and tita- nium. Dc-magne- tron sputtering of the constituent metals in a reactive ambient of argon and oxygen leads to formation of the respective metal oxides intermixed on an extremely fine scale in the desired composition . quite rough, opaque, and of ceramic quali- ty. By placing a collimator around each sputtering target to restrict the depoSition to a substantially perpendicular incidence, smooth, transparent electro-optic quality films are obtained. This work was done by Sarita Thakoor of Caltech for NASA's Jet PropulSion Laboratory. For further information, Cir- cle 91 on the TSP Request Card. In accordance with Public Law 96-517, the contractor has elected to retain title to this invention. Inquiries concerning rights for its commercial use should be ad- dressed to Edward Ansell Director of Patents and Licensing Mail Stop 305-6 California Institute of Technology 1201 East California Boulevard Pasadena, CA 91125 Refer to NPO-18221, volume and num- ber of this NASA Tech Briefs issue, and the page number. 125 TURBOMACHINERY DEVELOPMENT MADE EASY W·'~· -, ",,-' 4_ . . . .;. With advanced turbomachinery software systems from NREC you can balance performance, reliability, and cost. Or, we can do it for you. Product Design & Development Services include product specification, feasibility studies, fluid and mechanical design , controls engineering, finite element analysis, rerating, performance upgrades, and failure analysis. Specialized CAE/CAM Software Advanced technology software improves design, performance prediction , vibration analysis, and N/C machining of compressors, pumps, and turbines. Precision Manufacturing NREC provides the highest quality 5-axis machining of complex impellers, rotors, blades, and blisks, up to 60 inches, plus balancing, spin testing, and assembly. For More Information Please request free literature or contact Frank Hines to discuss your application. Phone 617937-4655 or Fax 617935-9052. NREC Northern Research and Engineering Corporation 39 Olympia Avenue, Woburn MA 01801 A part of worldwide Ingersoll-Rand Templates Aid Removal of Defects From Castings Fewer ultrasonic thickness measurements are needed. Marshall Space Flight Center, Alabama Templates have been used to correlate defects in castings with local wall thick- nesses. When the defects are ground away, the correlations are used to ensure that excessive material is not removed. The templates serve as adjuncts to pen· etrant-dye inspection for surface defects. The templates consist of full-scale repro- ductions, on clear plastic sheets, of appli· cable drawings of the cast parts. Grids are superimposed on the drawings (see figure). The applicable template is placed on a part to be inspected after the part has been coated with penetrant dye. Fbsitions of col- ored spots (indicative of defects) are noted on the template grid and recorded on the corresponding positions on a reduced re- production of the template in a laboratory notebook. Referring to the noted coordinates on a similar template that contains holes, an ultrasonic inspector measures the thick- ness of the wall of the part at unaccep- table defects only - an overall inspection is not necessary. The part is returned to the factory for removal of these defects by grinding. The wall at the location of each such defect can be ground to the allowable depth, as determined by the thickness at that point - no guesswork is needed. The length, width, and depth of each grindout r-------------------------~ A Typical Template is a full -scale repro- duction, with gridlines, of a drawing of a casting: in thi s case, showing the volu te side of a turbopump housing. The template is placed over the casting and oriented so that it matches corresponding featu res on the part. are recorded on the reduced version of the template in the laboratory notebook. This work was done by Robert G. Hendrickson of Rockwell International Corp. for Marshall Space Flight Center. For further information, Circle 61 on the TSP Request Card. MFS-29838 Coating of Molded Battery Substrates A suitable coat could enhance properties of su rfaces. W~ NASA's Jet Propulsion Laboratory, Pasadena, California ... Suitable materials applied to molds as powders, dispersions, or solutions could not only enable release of the molded parts from the molds but also enhance the properties of the surfaces of these parts. Conceived during the consideration of the molding of a carbon-filled plastic substrate for a lead/acid electrochemical cell, the concept could also be applied to the cast- ing of lead grids, to the casting of other substrates for electrodes of electrochemi- cal cells, or to other molding operations in which powdered materials adhering to the molded parts would improve the properties of the surfaces. In the case of the molding of a carbon- filled-plastic substrate for an electrode of a sealed lead/acid bipolar cell, there is a tendency toward poor adhesion of the ac- tive material to the substrate. In the pro- posed method, adhesion would be en· hanced by incorporating the active material into a surface layer during molding; the mold would be coated with powders of one of the commonly used lead/acid paste materials - such as lead oxides, lead sul- fates, and the like - as well as with car- bon powder. Because the molding temper- atures of a typical plastic are well below the melting temperature of any of these powders, the particles of the powders are expected to maintain their original form and to be partially buried in the surface of the resulting molded substrate. PbO par- ticles would be converted in later process- ing to Pb02 on the positive side or Pb on the negative side. The carbon particles would increase the surface loading, result- ing in a better bonding interface. This work was done by Terrance M. Larkin of The Gates Rubber Co. for NASA's Jet Propulsion Laboratory. For further information, Circle 20 on the TSP Request Card. NPO-18236 126 For More Information Circle No. 539 NASA Tech Briefs, September 1992 Shrink· Fit Solderable Inserts Seal Hermetically Connectors can be inserted or holes plugged by soldering in a normally unsolderable housing. Ames Research Center, Moffett Field, California A shrink-fit stainless-steel insert in an aluminum equipment housing allONs elec- trical connectors to be replaced by solder- ing, without degrading the hermeticity of the housing or the connector. Previously, damaged connectors were removed and replaced by welding - a method that could readily destroy electrostatic-sensi- tive components and harm the housing and internal cables. The steel insert avoids these problems because the connector can be soldered directly to it rather than welded to the unsolderable aluminum housing. The insert is a flanged 304 stainless- steel sleeve. The housing is made of 6061- T6 aluminum. The insert is machined so that its flange diameter is larger than the di- ameter of the connector mounting face, its inside sleeve diameter accommodates the connector body, and its outside sleeve di- ameter is 0.003 in. (0.08 mm) larger than the hole in the aluminum housing for an in- sert approximately 1 in. (25 mm) in diame- ter. Larger diameter inserts may have a greater diameter difference. The face of the sleeve flange is coated with 6OSn/40Pb solder. The mounting face of the connector is similarly coated. The sleeve is immersed in liquid nitro- gen at - 320 of ( -196 OC), while the hous- ing is placed in an oven at 250 of (121 OC). When the temperatures of the parts have stabilized, the parts are remcved. The sleeve, which has contracted from the cold, is quickly inserted in the hole in the housing, which has expanded from the heat. As the parts return to room tempera- ture, they return toward their original dimensions, forming a metal-to-metal seal between them_ Finally, the electrical connector is in- 304 Stalnless-Steel Insert Aluminum Housing Hermetically Sealed Electrical Connector Shrink-Fit Joint Placing an Electrical Connector in a Steel Insert maintains the hermetic seal of an aluminum housing. However, the cOnnector can be removed and replaced when necessary. It is merely necessary to melt the solder between the connector and the insert, remove the damaged con- nector, and resolder a new connector in place. serted in the sleeve, and its mounting face is soldered to the flange face on the sleeve (see figure). The seals between the flange and the housing and between the connec- tor and the flange have proven to be highly resistant to leaks, even after mechanical overloading and thermal shocking. This work was done by William C. Croucher of Martin Marietta Corp. for Ames Research Center. For further infor- mation, Qrc/e 97 on the TSP Request Card. ARC-11690 Spectrum-Imaging Detector Array With Integrated Filter The filter would be deposited directly on the array of photodetectors. NASA's Jet Propulsion Laboratory, Pasadena, California A proposed rectangular array of photode- tectors in an imaging spectrometer would include an integral filter, the transmittance of which would vary linearly with distance along one of the rectangular axes (the spectral axis). The filter would be depos- ited directly on the imaging array. Conse- quently, unlike a separate filter attached mechanically to the array, n would not there- after become misaligned or misregistered as a result of mechanical shock, vibration, or differential thermal expansion. The need for precise alignment and reg- istration of a separate filter cannot be over- NASA Tech Briefs, September 1992 emphasized. The distribution of transmit- tance of the filter must be matched to the dispersion of the diffracting element of the spectrometer. If the filter is misregistered as much as one-tenth the detector-ele- ment pitch along the spectral axis, the de- tectors can receive significant amounts of light at unwanted wavelengths. Similarly, rotation of the filter with respect to the ar- ray of detectors can cause blurring of wavelengths and loss of signal. Moreover, a gap must be maintained between the filter and the detector to allow for vibra- tions, but the gap can allow wavelengths to overlap between adjacent columns of detectors - that is, it can cause crosstalk. In addition, the gap can vary widely over the range of operating temperatures. Coating the array with a multilayer film of linearly distributed transmittance would overcome these disadvantages. Deposi- tion should be carried out before the ar- ray is assembled to the accompanying charge-coupled-device multiplexer. This is because the indium bumps that join photo- detectors to the cells of the multiplexer soften at about 70 °c, well below the tem- perature at which the film is formed. 127 This work was done by Clayton C. LaBaw of Caltech for NASA's Jet Propul- sion Laboratory. For further information, Circle 85 on the TSP Request Card. This invention is owned by NASA, and a patent application has been filed. In- quiries concerning nonexclusive or ex- clusive license for its commercial develoff ment should be addressed to the Patent Counsel, NASA Resident Office-JPL [see page 24]. Refer to NPO-18317. A Filter of Linearly Distributed Transmittance would be depos- ited directly on an array of photodetectors. The array, in turn, would be bonded with indium bumps onto multiplexer. ~~ Precise Countersinking Tool Precision is achieved with an ordinary hand-held drill. Goddard Space Flight Center, Greenbelt, Maryland A tool countersinks holes precisely with only a portable drill or magnetic-base drill; it does not require a costly machine tool. The tool produces 100° countersunk cones up to 1.300 in. (3.302 cm) in diameter. 128 HowToDes~A Shorter Circuit To Electronic Engineers Generate qUlllified leads and direct sales for your electronics products or services. Wc can show lOU how to get immcdiate. measurable results with Vflllufe (ollllllllllirulilllls' cooperati\e direct mail. You can put your offer in the hands of proven direct mail bu}crs for pennies per prospect. Velllure (OlllllllllliCUlilll/S is a leader in alternate response media. managing more than 70 card pac programs to over 15 million dccision makers. We rcach professionals in the clcctronics and computcr tcchnology fields. If",c don't hale a card deck that reaches lour audicncc. "'e'll find you one. Best of all. we take care of e\cry aspect of lour promotion from insert to mailing. 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THE SCIENTIFIC AND NUMERICAL SOFTWARE SPECIALISTS Numerical Algorithms Group Inc., 1400 Op~s Place, Suile 200, Downers Grove, IL 60515-5702 USA Tel : 708/971-2337 NASA Tech Brie/s, September 1992 For More Information Circle No. 428 133 Life Sciences ~~ Shape-Memory Probe Grasps Small Objects Foreign objects can be extracted from body cavities with minimal risk. Goddard Space Flight Center, Greenbelt, Maryland A device removes foreign objects from the ear canal, nose, or throat with little risk of damage to tissue. The device includes a thin, flexible wire that is inserted into the obstructed cavity. The wire is made of a titanium/nickel or other shape·memory al- loy. Once the wire is properly positioned, it is made to bend into a hook, tweezer, or other " remembered" grasping config- uration by heating it above a critical tem- perature. The bend surrounds the offend- ing particle, which can then be extracted. The new device makes it unnecessary to insert a curette, pair of forceps, or other relatively large, unwieldy instrument into an ear, nose, or throat and thus eliminates the danger of puncturing the eardrum or other tissue. of Goddard Space Flight Center. For fur· ther information, Circle 24 on the TSP Re- quest Card. This invention is owned by NASA, and a patent application has been filed. In- INSERTION OF DEVICE quiries concerning nonexclusive or ex- clusive license for its commercial develop- ment should be addressed to the Patent Counsel, Goddard Space Flight Center {see page 24}. Refer to GSC-13306. REMOVAL OF FOREIGN OBJECT The device (see figure) includes a cylin- drical housing (like a common flashlight, but narrower) from which an elongated loop of shape·memory wire extends. After the ti p of the loop has been inserted into the cavity so that it overlaps the foreign object, the operator pushes a switch on the housing to send a small electrical cur· rent through the loop. The current heats the wire to slightly above body tempera- ture; the wire then "remembers" its bent shape. The source of current could be a battery in the housing or could be an ex- ternal transformer and rectifier. A loop of Shape-Memory-Alloy Wire is inserted into the ear canal. A small lamp helps the operator guide the t ip to a foreign object. Heated by current, the tip grasps the object. This work was done by Earl D. Angulo 134 Supplying a full line of portable, digital recorders for shock & vibration monitoring and recording . PC- compatible and programmable - Battery powered - Full waveform recording - Completely self- contained with built-in 3-axis accelerometers. Remote preprogrammed operation from hours to weeks. Compact systems under 2Ibs., complete! Let our unique digital recorders turn your desk-top PC into an environmental data collection and analysis system for vibration, shock, and (optionally) temperature and relative humidity. All field data captured in a single, self-contained instrument package. Trans- fer data to your PC for report generation, waveform graphics, statistical and PSD analysis. Link to laboratory controllers to simu· late and reproduce actual field measurementsl For More Informatio n Circle No. 399 NASA Tech Briefs, September 1992 Apparatus Induces and Fixes Small Aquatic Organisms The apparatus is small , compact, light in weight, and self-contained . IF.4 The New Standard of Excellence. Ames Research Center, Moffett Field, California A portable, self-contained apparatus is designed to in- duce and fix live jellyfish and other, small aquatic organisms in microgravity. It is small , light in weight, and reliable , unlike previous apparatuses of the same type. Operation of the apparatus requires a minimal amount of a technician's time. It should be adaptable to use in biological tests and experi- ments at remote locations on Earth . The apparatus (see figure) isolates the live organisms from toxic substances until the desired time of introduction. It includes a set of plastic syringes, each containing an inner, sealed , burstable bag filled with a desired solution . The syringe is secured to a cylindrical aluminum guide, which slides into a plastic housing. The housing connects the syringes to a bag that contains the specimens. The housing includes a rubber septum through which the solutions are injected. This system provides two levels of containment between the toxic substances and specimens with no leach- ing of chemicals into the specimen bag prior to time of introduction. At the time of introduction of solution from a given syringe, the technician forces the cylindrical guide that holds the syringe into the housing , thereby forcing the needle of that syringe through the septum. The technician then pushes the plunger of that syringe until the bag bursts and the contents are injected into the specimen bag . The technician is iso- lated from toxic substances by two outer bags, providing at least three levels of containment of fluids. The apparatus was designed for use on Aurelia jelly- fish- an extremely fragile organism. It was tested on the ground with Aurelia and proved highly successful. It was found that the entire sequence of operations can be com- pleted in about 15 seconds. The work was done by Christopher Todd of Insystems for Ames Research Center. No further documentation is avail- able. ARC-12B14 Needle With Sleeve Septum Specimen Bag Containing 90 mL of Artificial Sea Water. 50 mL of Air. and 6 mL Sodium Cacodylate Buffer In Burstable Bag Inside ~,r-~I 50 Jellyfish or Thyroxine in Burstable Bag Inside The Syringe-and-Bag Assembly is a compact, lightweight self- contained. portable apparatus that can be used to introduce vari- ous liquids to aquatic organisms at desired times. NASA Tech Briefs, September 1992 The most comprehensive, authoritative scientific dictionary now available, the Academic Press Dictionary of Science and Tech- nology offers you, in one volume, the largest collection of scientific terms available in any single reference source. Containing complete, practical definitions for approximately 124,000 words (not counting abbreviations), the Dictionary covers key terminology in 124 fields of science and technology-including molecular biology, computer science, phy ics, engineering, chemistry, ecology, behavior, geo- phYSics, veterinary science, mathematics, astronomy, biotechnology, and numerous other fields. Its Key Features Include: • ingle volume, large 81" x 11", double-column format for ea yacce • More m dical terms than any other general scientific dictionary now available • More coverage of subfields of medicine, including rapidly growing dis iplines such as oncology, radiology, hematol- ogy, cardiology, and toxicology • early 2,000 detailed illustrations and technical photographs, including 24 pages of color plate • Pronunciation guides for difficult Or phonetically irregular tenm • Complete appendix of frequently consulted cientific data, including the periodic table, chronology of science and standard weights and measure t a new tandard of excellence by adding the Academic Press Dictionary of Science and Technology to your reference collection. It will be your reference of choice. eptember 1992,2,432 pp., $] ]5.00/ ISB : 0-12-200400-0 Prepublication Price: $99.50' 'E.xpires on final da)' of month of puhlicmion . Order from your local bookseller or directly from o ACADEMIC PRESS HBJ Order Fulfillmem Depanmem .. 17915 6277 Sea HanXlr Drive, Orlando, FL 32887 CAll TOU FREE 1-800-321-5068 or FAX 1-800-336-7377 Prices subject to charoge Without notice. Cl l992 by Acad.m~ Press. tnc. All Rights Reserved LKlWRlCP-1l11l9'1 For More Information Circle No. 307 135 -News & Tips on Mi~~~~~~l , . - , I -For optimum results in light microscopy, precise control of the light path should - start before the light reaches the - specimen. Alignment of the illuminator is - a critical part of this control. - EQUIPMENT SPECIFICATIONS The microscope must have an adjustable illuminator, halogen or arc. PROCEDURE 1. Detach lamp housing and cord from power supply. 2. Remove socket from lamp housing. Make sure correct bulb is installed straighl into lamp socket. Reinstall socket. 3. Remove ground glass. 4. Look into lamp collector towards filament and pre-align lamp socket until filament is roughly centered. If a mirror is present, the filamenfs image should be adjusted below (halogen) or adjacent to (arc) the real filament. Both images must be centered. 5. Reconnect lamp housing and power supply. 6, Open aperture diaphragm and close field diaphragm (if present) and remove one objective. 7. Check and align light source image projection onto stage for centralion. 8. Reinstall objective and ground glass. BENEFITS • Evenly illuminated image. • Brilliant image without reflection or glare. • Minimum heating of specimen. Contact us and we'll send you a 15' x 21 ' poster of a - _ microscope light path. SEE WHAT YOU'RE MISSING Microscope Division Carl Zeiss, Inc. One Zeiss Drive Thomwood, NY 10594 Call: 800-233-2343 Fax: 914-681-7446 -------------.. -- 136 For More Information Circle No. 566 Books and Reports These reports, studies, handbooks are avail- able from NASA as Technical Support Pack- ages (TSP's) when a Request Card number is cited; otherwise they are available from the National Technical Information Service Gravity, Calcium, and Bone: Update, 1989 Data on effects of gravitation on skeletal adaptation, calcium metabolism, and growth processes are reviewed, A report reviews recent short-term flight and ground-based experiments that bear on the effects of I g and 0 g on skeletal adaptation , calcium metabolism, and growth processes. The results of these studies indicate that two principal com- ponents of calcium metabolism - the calcium endocrine system and bone - respond promptly (within days) to changes in the orientation of the body in gravitation and to weightlessness. The vitamin D hor- mone may be the best candidate for mobilizing bone mineral early, and gravity- dependent gradients that probably involve the cardiovascular system may have a significant role in its distribution at the whole-body level. These observations pro- vide a better perspective for the interpreta- tion of mineral-balance studies in healthy ground-based and astronaut subjects. During inactivity or weightlessness, net losses in bone minerals may be attribut- able more directly to alterations in the functions of the gastrointestinal tract and kidney and changes in diet than to direct gravitational effects. However, studies do show a link between gravity and the dis- tribution of and deposition of bone miner- als. Thus, the effects of spaceflight or bed rest on the biomechanics of bones appear to be more severe than they are on total body bone mass. The concentration of minerals in the lumbar vertebrae has been monitored in several recent studies following one in 1983 that reported a reduction of 3.8 per- cent in the average density of the 2d through 4th lumbar vertebrae following therapeutic bed rest in 28 patients with prolapsed intervertebral disks. Quantitative computer tomography measurements made on four cosmonauts before and after they spent 6 months in space in a regime that included daily exercise showed no significant change in the average density of the 2d lumbar vertebra. Studies of bed-rest subjects show varied individual responses. In one study, five out of six non-exercising bed-rest (horizontal) subjects showed no reduction in bone density in the 2d through 4th lum- bar vertebrae; the remaining subject show- ed a 3-percent decrease. Another study reports increases of up to 12.6 percent in density of the spongiosa of the lumbar vertebrae of three bed-rest subjects after 120 days at So head-down tilt. In a study of 19 subjects deSigned to test the effect of isokinetic and isotonic ex- ercise on the tolerance of bedrest subjects to standing after bed-rest, measurements of density of minerals on the 2d through 4th lumbar vertebrae before and after 30 days at 6° head-down tilt revealed no dif- ferences between either exercise group and the control (no-exercise) group. However, two subjects in the isokinetic- exercise group showed Significant densi- ty changes, -7 and +10 percent, respec- tively, with changes in serum parathyroid hormone (PTH) in the opposite directions, This is consistent with the known effects ' of PTH in enhancing bone resorption. There are also indications that changes in the serum level of the vitamin D hor- mone, 1,2S-D, may playa role in the mobil- ization of bone calcium. Recent proposals that PTH governs the differentiation and number of bone cells and that 1,2S-D governs cell activity are suggestive of the following sequence of events as an ex- planation of data from four astronauts on circulation hormone levels measured be- fore, during, and after a 7-day spaceflight: enhanced mobilization of calcium from bone related to the observed transient in- crease in 1,2S-D, followed by suppressed mineralization in unloaded bones after a few days, with no increase in the number of osteoclasts or osteoblasts. The results of experiments with rats suggest a gravity- dependent distribution of mineral in the whole skeleton, affected by responses of the cardiovascular system to changes in position and gravity, These experiments also showed a decrease in bone strength without changes in bone density, This work was done by Sara B. Arnaud and Emily Morey-Holton of Ames Re· search Center. To obtain a copy of the report, "Gravity, CalCium, and Bone: Up- date, 1989," Circle 37 on the TSP Request Card. ARC-12717 Effects of Exercise During Prolonged Bed Rest Exercise helps preserve physical and mental condition, A report describes an experiment to in- vestigate the effects of periodic, intense, short-duration exercise during bed rest. More specifically, the investigators sought to determine the efficacy of isotonic (cycle) and isokinetic (flexion/extension) leg exer- cises in counteracting the deleterious ef- fects of bed rest upon the physical and NASA Tech Briefs, September 1992 mental conditions of the subjects. Nineteen men, aged 32 to 42 years, were divided into three groups: a control group of five for whom exercise was not prescribed, a group of seven who per- formed the isotonic exercise in a supine position, and a group of seven who per- formed the isokinetic exercise in the supine position. The exercises were per- formed near peak levels for 30 min in the morning and 30 min in the afternoon 5 days per week. The experiment began with a 7-day am- bulatory control period during which the subjects equilibrated on a standardized diet of normal fresh and frozen foods. This was followed by 30 days of bed rest (inter- rupted by the prescribed exercises) with the beds tilted 8' down at the head ends. The experiment concluded with 4.5 days of ambulatory recovery. For each subject, data were taken on the capacity for work (measured in terms of the peak rate of uptake of oxygen), en- durance and strength of the muscles, toler- ance to sitting up, equilibrium, posture, and gait. Data were also taken on atrophy of the muscles, mineralization and density of the bones, endocrine analyses concerning vasoactivity and fluid and electrolyte balances, intermediary metabolism of the muscles, mood, and performance. While significant changes in density of the lumbar spine and radius were not de- tected in the majority of subjects, there were clear effects of the exercises on some aspects of mineral and fluid metal> olism. The isokinetic exercise prevented in- creases in sublingual cell minerals 0b- served in controls, hypercalciuria after 27 days, and decreases in both major calcium regulating hormones. Magnetic resonance spectroscopy measurements of muscle phosphorus revealed that the high index of reserve energy (phosphorus/phospho- creatine ratios) in controls after bed rest was also prevented only in the isokinetic- exercise subjects tested by an isometric exercise. On the other hand, plasma vol- ume was maintained by an isotonic exer- cise. These results suggest that isotonic and isokinetic exercises have different ef- fects on mineral and fluid metabolism. Ele- ments of both types of exercise may be needed to counteract the deleterious metabolic effects of bed rest. The subjects were found to have main- tained a relatively stable mood, high morale, and high esprit de corps through- out the study. The performance of almost every subject improved in nearly all tests. The isotonic exercise, as opposed to iso- kinetic exercise, was associated more with decreasing levels of psychological tension, concentration, and motivation; and im- provement in the quality of sleep. The capacity for work was maintained during bed rest with isotonic exercise; it was not maintained with isokinetic or no exercise. In general, there was no significant decrease in strength or endurance of arm or leg muscles during bed rest, despite the atrophy of some leg muscles. The toler- ance to sitting up was reduced similarly in all three groups follOWing bed rest. Bed rest resulted in significant decreases in the stability of posture and of the self-selected lengths of steps and stride, and speed of walking. These characteristics were not in- fluenced by either exercise regimen. Pre- bed-rest responses were restored by the 4th day of recovery. This work was done by S. Arnaud, P. Berry, M. Cohen, J. Danelis, C. DeRoshia, J. Greenleaf, B. Harris, and L KeN of Ames Research Center, E. Bernauer of the Uni- versity of California, M. Bond of Loredan Biomedical, S. Ellis of San Jose State University, P. Lee and R. Selzer of NASA's Jet Propulsion Laboratory, and C. Wade of the Letterman Institute of Research. Fur- ther information may be found in NASA TM-101045 [N90-139261 "Exercise Coun- termeasures for Bed Rest Deconditioning. " Copies may be purchased [prepayment required] from the National Technical In- formation service, Springfield, Virginia 22161, Telephone No. (703) 487-4650. Rush orders may be placed for an extra fee by calling (800) 336-4700 ARC-12190 NEW, FREE 288 Page Catalog and Referenceliuide The most informative Data Acquisition Catalog and Reference Guiduou've ever seen, Packed with solutions for all of your data acquisition and control needs. 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I I Return to: Keithley MetraByte I 440 Myles Standish Blvd. Taunton MA 02780 KEITHLEY METRABYTE I NTB 9/92 (508)880-3000 .J I.iii ______ _ D A T A ACQUISITION DATA ACQUISITION, COMMUNICATIONS & SOFTWARE PRODUCTS FOR IBM PC/XT/AT, PS/2 AND MICROCHANNEL COMPUTERS AND COMPATIBLES NASA Tech Briefs , September 1992 For More Information Circle No. 425 137 St~stical Analysis V Library for Hewlett-Packard Computers and PCs running HTBasic Developed by Hewlett-Packard Engineers Over 10.000 Users Worldwide Ready to Go - No Programming Necessary 10 Floppies fun of High Powered Statistical Routines including 2 Floppies of Graphical Routines Also, ask about our<:Sillflal Processin!L:> Graphics Editor, and much more ... ® Parametri~~~1 P.O. Box 8035 Loveland, CO 80537 Phone or FAX (303) 667·4030 For More Information Circle No. 575 40 Years Experience in Sapphire Machining • OPTICAL DOMES • WINDOWS • PRISMS • TUBES • WEAR PARTS • LARGE SAPPIllRE PARTS • SUBSTRATES • Precision Equipment • Modern Facilities • Approved Quality Program • Fast Service • Manufactured in the U.S.A. rlIISIlCII ~[j]~D Box 9006 Quakertown, PA 18951-9006 (800) 647-3892 FAX (215) 536-n50 138 For More Information Circle No. 386 New on the Market The CL-2S0 system from Ono Sokk! Technology Inc., Addison, IL, emJ ploysa unique processing technique for highly accurate noncontact thickness measurements of conduc- tive and semiconductive materials. The system calculates thickness from gap capacitance regardless of the material type, magnetization, color, roughness, or relatiVity. The tech- nique also is immune to magnetic fie lds and ambient light. For More Information Circle No. 800 BBN Systems and Technologies, Cambridge, MA, has announced Release 2.2 of its BBN/Probe™ time series analysis software. The inter- A 3D input peripheral developed by Pixsys, Boulder, CO, simplifies the use of 3 D CAD and computer graph- ics software. The FlashPoint and FlashTracker 3D digitizing systems measure 3D points in space to track the motions of people, equipment, or instruments and create computer- ized models of real-world surfaces. The devices are easily configured by the user for integration into vir- tually any commercial or custom software package. For More Information Circle No. 798 Delta M Corp., Oak Ridge, TN, has introduced a line of thermocouples that employs nontoxic Hafn ia (Hf02l, a highly stable insulation material compatib le with the same refractory materials as potentially hazardous beryll ium oxide. The thermocouples can measure pro- cess temperatures up to 22000 C. and are avai lable in S, R, B, G, D, and C types with sheath materials of alumina, molybdenum, tantalum, platinum, or zirconia . For More Information Circle No. 794 active data reduction, analysis, and I--------------t graphics package offers direct ac- cess to gigabytes of data from such sources as telemetry and flight test systems, simulations, vehicle and range testing, and physiological re- cordings. New features include cal- endar time format to support appli- cations where data is collected over long periods at slower rates and multiple vertical axis scales for over- laying data with different scales on a single graph panel. For More Information Circle No. 790 The DynaSighr® computer work- station viewing accessory from Origin Instruments Corp., Grand Prairie, TX, is a low-power optical radar that enab les dynamiC per- spective displays and head-con- trolled pointing systems. The com- pact, self-contained sensor opens a 3D virtual window on real-time displays to extend the user's ability to comprehend complex spatial ar- rangements in 3D models . For More Information Circle No. 796 The Little PL(TM miniature control computer from Z-World Engineer- ing, Davis, CA, is C-programmable and measures just 4" x 3". Priced at $195, the programmable logic con- troller features eight optically iso- lated inputs, eight relay driver out- puts, a built-in switching powersup- ply, and RS-4B5 serial communica- tions. A simple expansion bus with open architecture allows unlimited inputs and outputs. For More Information Circle No. 788 C.ITOH Technology Inc., Irvine, CA, has introduced the DB80 graphic LCD module, designed to provide a simple man-mach i ne interface wh i Ie saving space. Operator instructions such as sequencing, timing, and sys- tem status are avai lable on a keypad enhanced with changing color alerts _ that blink or beep. The D8BO inte- grates a low-power graphic LCD, utilizingsupertwisttechnology, with a custom IC driver- all on the key cap of a single-pole, Single-throw, momentary-contad switch measur- ing less than one square inch. For More Information Circle No. 792 NASA Tech Briefs , September 1992 New on the Market Dataq Instruments Inc., Akron, OH, has introduced a line of low-cost Wi ndows-compatible data acquisi- tion hardware products. The boards feature wide measurement ranges, the broadest programming flexibil- ity available, input and output scan lists, dual DMAoperation, free driver software, on-board counter/ timers, signal averaging, burst sampling, analog triggering support , and "potless" digital calibration . For More Information Circle No. 774 A sealed lever latch manufactured by South co Inc., Concordville, PA, easily accommodates both milled and CNC routed panel preparation plans. The latch installs in a single rectangular hole and provides over- all sealing performance to meet or exceed NEMA 12 and IP 65 require- ments. A flange helps compress an optional perimeter gasket for maxi- mum sealing and also masks cos- metic panel irregularities caused by routing orsawing the installation hole. For More Information Circle No. 786 SNAP, a PC-based system for dis- placement field measurement from TAU Corp., Los Gatos, CA, auto- matically measures physical dis- placement within materials stressed to the point of deformation and fail- ure. Highly accurate displacement field measurement compares the position of selected points on the material's surface-before and after stress is applied by thermal or me- chanical loads-a llowing users to ca lcu late safe stress levels. For More Information Circle No. 782 Parametrics Inc., Loveland, CO, has released the Statistical Analysis Li- brary software package containing over 500 proven statistical and graphical algorithms. The package requires no programming and is designed to take the user step-by- step from data entry through all phases of data analysis and presen- tation. A data manipulation front - ---,! end allows users to edit, scan, join, AVX Corp., New York, NY, has an- list, select portions, recode data sets, nounced a .1 ~F, X7R multi-layer and create subfiles. ceramic chip capacitor in an 0603 For More Information Circle No. 780 case size. Offering circuit designers maximum board density, the capacitor's X7R dieiectric allowsoniy a 15% change in capacitance value over an operating range of -55 to 125 0 C. The capacitor is well-suited for applications in harsh environments or where tempera- ture variations occur. For More Information Circle No. 784 An on-line infrared temperature measurement system from Wahl In- struments Inc., Culver City, CA, has high-resolution optics to measure surfaces as small as .019" diameter through glass ports. The model HSM672 Heat Spy® infrared moni- tor enables small surface measure- ments where contact measurements are impractical. Accuracy is ± 1.0% of reading, and the unit has push-to- test internal ca l ibration. For More Information Circle No. 776 NASA Tech Briefs, September 1992 Tektronix Inc., Beaverton, OR, has in- troduced STEREOTEK" Mkll stereo- scopic glasses utilizing patented Pi- cell liquid crystal technology for high contrast. The glasses feature tether-free operation via an infrared link, bat- tery life up to 200 hours under nor- mal operation, automatic flickerless mode, and a large lens area. They can be used to view real-time stereo im- ages bycombiningcameras,scan con- verters, and a monitor. For More Information Circle No. 778 A reputation for dependable quality and service has made Sigmund Cohn the trusted name for more than 90 years. We offer Platinum and Platinum Alloys with high or low Temperature Coefficient of Resistance and high or low electrical resistance. They have outstanding corrosion resistance, high tensile strength, excellent ductility and precision controlled diameters. We offer Platinum 99.999%. Or choose from our line of Platinum Alloys which includes: • Tungsten Platinum • Iridium Platinum • Rhodium Platinum • Nickel Platinum We also offer Platinum Alloys to meet your diverse requirements. Let us help determine which are best for you. Write or call for a brochure. For More Information Circle No. 390 139 .. . get the performance and reliability you need, without having to give in to SA BENEFITS » Combined CPS/Loran for improved reliability »Combined CPS/Loran for ultimate accuracy » Combined CPS/Loran for redundancy » Combined CPS/Loran for enhanced performance under selective availability (SA) APPLICATIONS »Provides the ultimate metrology laboratory standard » Provides Master Clock for Telecommunications systems » Provides CPS/Loran timing interoperability monitoring The Loran-C Assist module plugs into any AUSTRON CPS receiver providing both redundancy and performance enhancement in time and frequency applications. When SA is on, the module automatically weights the Loran-C data more heavily to alleviate SA's effects. When SA is off, the weighting will depend on the quality of the data received from each system. The receiver compares the CPS determined position to its internal global Loran-C database to choose the best available Loran-C transmitters. Should CPS become unavailable, Loran 'Assist will carry on producing reliable time and frequency signals until CPS returns. Many other option modules are available to meet your applications' requirements. Write today or call for a FREE CPS brochure .. .from The Masters of T ime. 111111111 FTS/@AUSTRON Datum companies working together to meet your needs . .. P. O. BOX 14766 AUSTIN. TX 78761 . TEL (512) 251 -2313 • FAX (512) 251-9665 For More Information Circle No. 434 140 New literature The Controls Oivision of American Precision Industries , Buffalo, NY, has released a guide to step motor systems design . The catalog pro- vides an illustrated glossary as well as formulas and helpful hints for system calculations. Sections ad- dress indexers, step motors, modu- lar drives, packaged systems, and accessories. For More Information Circle No. 702 A brochure re leased by Micro As- sembly Systems Inc., Willimantic, CT, details the Stick-Screw System, an assembly tool designed to speed as- sembly time, improve quality, and reduce costs. The system employs an air-powered rotarydriver and "sticks" of up to 90 serially-connected hex- head screws. For More Information Circle No. 704 A 12-page brochure from METRUM Information Storage,J ittleton, CO, describes the capabilities and fea- tures of its RSS-600v and RSS-48b automated tape storage libraries . By combining state-of-the-art ro- botics and the high-density RSP- 2150 tape drive with rei iable, low- cost ST-120 tape cartridge media, the products offer high data storage capacities per square foot of floor space, high data transfer rates, and fast data access ti me. For More Information Circle No. 708 A brochure released by Arvin TO Center, Columbus, IN, describes its thermal diffusion process. An ad- vanced method of hardening steel surfaces to reduce galling, seizure, and corrosion, the TO process re- duces downtime, tool maintenance, f--------------I and replacement and lubrication KineticSystems Corp., Lockport, IL, has published a VX lbus (VMEbus extensions for instrumentation) product catalog describing over 35 new I/O modules for real-time data acquisition and control appl ica- tions. The catalog includes analog and digital I/O, counters, pulse gen- erators, signal conditioners, and transient recorders. costs. TO-treated materials have a surface hardness ranging from 3200 to 3800 on the Vickers hardness scale. For More Information Circle No. 710 Control Laser Corp., Orlando, FL, has released Industrial Strength Laser Marketing: Turning Photons into Dollars, a comprehensive guide to beam-steered laser marking sys- tems. The 50-page publication ad- dresses the operation and design of both Nd:Y AG lasers and beam- steered laser marking systems, re- views the prinCiples of laser interac- tions with materials, and covers inte- gration of laser systems with host computers and automated work cells . For More Information Circle No. 714 For More Information Circle No. 706 r----------------1 f--------------I A 184-page catalog from AIN Plas- The Capacitor Handbook from Cj Publishing, O lathe, KS, combines capacitor theory with circuit appli- cation advice. The first chapter cov- ers capacitor fundamentals with subsequent chapters dedicated to the various dielectric capacitor types including ceramic, plastic film , aluminum electrolytic, tanta- lum, glass, and mica. For More Information Circle No. 712 tics Inc., Mt. Vernon, NY, highlights the company's full lines of mechani- cal plastics, sheet, rod, tube, film, and accessories. Featured new prod- ucts include ABS tubing, Pharmed tubing, polypropylene pipe, Hyzod AR polycarbonate sheet, Kynar schedule 80 pipe, Kynar bushing stock & tubing, Vespel plaques, and transparent fluorescent vinyl. For More Information Circle No. 730 NASA T'ech Briefs, September 1992 New Literature A brochure publ ished by Intel Corp., Santa Clara, CA, describes the 801 70NX electrically-trainable ana- log neural network chip, which of- fers an innovative solution to real- time pattern recognition and signal . processing problems. The ch ip com- bines advanced IC technology with a high-density parallel architecture to deliver greater throughput per dollar than alternative technologies. Its integration and low power re- quirements make it a high-perfor- mance embedded solution for com- pact, low-power systems implement- ing small- to medium-size, multi- layer neural networks. For More Information Circle No. 718 A static control products catalog from Graseby Plastic Systems Inc., Marlboro, MA, introduces a variety f----------------j of products including the Statproof The latest ed ition of the Un igraphics Product Catalog offers a compre- hensiveoverviewofCAD/CAM/CAE products and services available from McDonnell Douglas Systems Inte- gration Co., Maryland Heights, MO. The Unigraphics system features modules with capabilities in solid Zinc-Free Floor Finish and a heel grinder with a new D-ring fastening system. Instructions are included for such applications as workstation, mo- bile personnel , test and measure- ment. material handling, clean room, and office products. For More I nformation Circle No. 71 6 modeling, surfacing, analysis, draft- 1--------------1 ing, and machining. For More Information Circle No. 728 Minco Products Inc., Minneapolis, MN, has released an updated design f----- - --------I and capabilities brochure for f1ex- A brochure from B-J Enterprises Inc., Albany, OR, describes the com- pany' s expanded capabilities in manufacturing custom parts and assemblies from refractory and re- active metals. Capabilities include deep draw forming, spinning, forg- ing, fabrication and welding, CNC turning and milling, tube bending, and stamping. The company spe- cializes in tantalum, niobium, mo- lybdenum, tungsten, zirconium and vanadium metals and their alloys. For More Information Circle No. 724 circuits. The 28-page guide features expanded coverage of rigid-flex cir- cuitsand surface mount technology, and a section on impedance and electrical noise control for high- speed signal transmission. It also discusses the differences between hardboards and flex-circuits, ex- plains manufacturing steps, lists rec- ommended tolerances, and defines common flex-circuit terms. For More Information Circle No. 726 DSM Engineering plastics, Reading, f---------------j PA, has released a brochure on its TheABCsofDMMs, a 1 6-pagebook- let produced by John Fluke Mfg. Co. Inc., Everett, WA, offers a short course on the operation, capabili- ties, and selection of digital multi meters {DMMs).lt features sec- tions on the com mon uses of a DMM, ac and dc voltage and current mea- surements, resistance, continuityand diode tests, and multi meter safety. For More Information Circle No. 722 NASA Tech Briefs, September 1992 Stanyl® 46 nylon that provides per- formance data and a complete prop- erties profile of all grades. Stanyl 46 offers a more symmetrical chain structure and a better crystallization rate than other nylons, yielding ex- cellent heat and chemical resistance, high stiffness and low creep at el- evated temperatures, and reduced cycle times for injection molding. For More Information Circle No. 720 For More Information Circle No. 444 Thermal-Ribbon™ Resistance Thermometers FORM /" FIT Aerospace instrumentation • Medical device Process control • Surface sensing FUNCTION Flexible resistance thermometers conform to surfaces for pre- cise thermal respon e. They're small, rugged, lightweight, fast responding. And you can install them almost anywhere. • Platinum to U. . or DIN standards; nickel, copper, nickel-iron • Kapton, silicone rubber insulation • -200 to 2200e range 7300 Commerce Ln. Minneapolis, M N 55432-3177 USA MINCO PRODUCTS , INC. Phn: 6121571-3121 Telex: 687-9025 FAX: 6121571·0927 For More Information Circle No. 541 141 THE TECHNOLOGY CONNE(7.10N To Advertise Call (800) 944-NASA Dalabasesllnforma- I lion Searches Knowledge Express Data Systems • Technology Transfer • Competitive Intelligence • Regional & Global Competitiveness Knowledge Express 1M is the new online information service en- abling you to evaluate collabo- rative research and licensing op- portunities from U.S. govern- ment laboratories, U.S. univer- sities, and companies. For a free demonstration disk, call today: (800) 248-2469 This is what the Federal Laboratories 'Database can put at your fingertips: • 2,000 Federal Labo- ratories, Facilities and Centers • $70 billion in R&D • expertise in 170 Critical Technologies • specialized laboratory equipment For information on the PC ($495) and Macintosh ($695) versions of the FLO contact the: Mid-Atlantic Technology Applications Center 800-257-2725 Technologies for Transfer NEW! MathViews™forWindows MA TlAB compatible ~nterpreler for WIndows • Matnx and Array Algebra • Complex Numbers and Signal Processing • 20 and 3D GraphICS WIth Clipboard SUppon • Wnnen InC +-+ • AvaIlable for boensmg The MathWizards (619) 457-2971 FAX (619) 458-5849 T~"'''''~cI __ """",,,. Technology Transfer I Publications Are You Serious About Technology Transfer? II so, you'll prof~ from Technology Access Repon, the leading ,ndependent, practical newsletter in the field. Technology Access Report w,lI help you master the process and ,ncrease your returns from technology transfer You will find licensing and spinoff opportunit,es from univers,tles and federal labs, for all industnes and technologies. Special Offer:-{)rder your valuable, exclusive Technology Access Re- source Kit: • Concise, durable annotated directory of the key tech transfer resources • Current issue of Technology Access Repon • Comprehensive, five·year guide to Technology Access Rspon articles • Discount coupon worth $50 towards your subscription (regularly $447 for 12 monthly issues) • All for just $9.95 (AmexlMCNisa, cash or check). Call H100i959-1059, fax 5101549-4342 or write to Technology Access Subscriber Ser· vices, P.O. Box 2189, Berkeley, CA 94702 Technology Transfer Business -The MagaZIne for Profitable Partnerships· A new quarterly publica- tion from the publishers of Washington Technology to excite industry leaders about successful imple- mentation of advanced technologies for enhanced competitiveness. Yearly subscription: $25 Advertising Space Available Contact: John Sanders, Publisher 1953 Gallows Rd., #130, V,enna, VA22182 703-848-2800, ext. 151 r-{lciiiiiiii_iiiiiiiii~~~il( =)~==;:;;j\1::I-..,20 inch Stroke " 7 Small. Inexpensive Very easy to interface POSITION SENSOR TECHNICAL INNOVATIONS, 2490 Lee Blvd., Cleveland, OH 44118 216-371-2222 142 Professional Serv ices Patent A ttorney Robert E. Maim, PhD . (M.I.T.) Attorney At Law Post Office Box 522 Pacific Pa lisades, CA 90272 Tel : (310) 459-8728 Fax: (310) 573-1781 ~SUbjeCI ~W-"'.Index __ A ACOUSTO-OPTICS E/rnIoaI.ng bias In acouslO-OPllCal SPeCtrum ana.,... page 50 NP().I8215 ADAPTERS fbver I0OI adilPler \01' T handle $Clews page 104 KSC·llS14 AERATION Sorbem-bed Clop.dryng sys'em page 116 MFS-28567 AERODYNAMIC STAl UNG Schleen ~OO'apnc slL.des Of dynarnc stall page 110 AAC-12471 AIRFOILS Schllefen phokIgIacnc SIUOIeS 01 0jnamIC: stall page 110 ~12471 ALGEBRA Aoooc contrOl based on spaha/-Opefalor algebfa page lIS NP().I7918 ALGORITHMS SystematIC disturbance oI00elffialrotall()f'lal lIa,ec1Ory page 100 MC-12700 AMPLITUDE MODULATION Eltect 01 phase un balance 11'1 product """""'0< page 57 NPOI8293 ANECHOIC CHAMBERS Arnond-Shaped leSt bOdy P8ge 32 LAR 13747 ARC WELDING Oleapel' cUSlom stMeIdIng Ct4)S tor arc -.. paoe 118 MFS·29815 lDng wearlOg wore guide lor welding IOfctl page 121 MFS 29829 ARRAYS Speclll"nHrT\8glng (\elec lor 8Hay with InletjJr31ed 1~ler page 127 NP().I8317 ASSEMBUNG GuocIe"" __ '" eiecltlC8l comec1Of t)IIge 123 MFS28582 ASTROMETRY St\.ldy 01 space-based op- tcal .,terlerometer paoe 74 NPO 18193 ATOMIC CLOCKS AtOfT'lC Clock based on WIear I0I"l trap page 46 NP().I8382 B BACKUPS Manual OIoe"nde b eIec IromechanlCal taICh page 117 GSCI3383 BAll BEARINGS FIXture lor teslltlQ ball beatings under radial lOads page 106 MF$.28589 BAYES THEOREM IteratIVE! Bayeslall cLassdahon JI'I poIatrneuc SAR page 129 NP().I8308 BED REST Ef1ects 01 exerCISe ciJrlng prolonged bed resl page 136 AAC-1219J BtoLDGICAL EFFECTS AWilraiUS II'O.IceS and lIlIeS smaI aquatIC """""'"" page 135 AR;12814 BONE DEMINERAUZATION Gravrty. calctUrTl. and bone upjale. 1989 page 136 ARC12717 c CAMBER Natural-lIoN WIIl9 page 105 lAR14281 CAPACITORS Biaxial)' stu~tched DQIyCartlOnalelllm tor caoec .... page 78 NP().18O!lO CARRIER FREOUENCIES Open-loop acqutS.tlOl"l of suppressed camer ...... ~ page 48 NP().I8364 CASTING li:!o"Patesa.dr~oI deJects hem casl.ngs page 126 MF&29838 CATHODES FabrIC3hon of melal chloude caUlOdeS by sll''IIerang paoe 76 NPO 18118 CHARGE CARRIERS Q\a(ge.carrtet-SCalteflOg spectroscopy With BEEU page 58 NP().I8411 CHARGE COUPLED DEV1CES ceo WIth bacKoStde II- IurTw\allOl"l and charge , ....... t8ge :J) NP().I8387 O RCUIT PROTECTION Faraday cage protects aguo5'''''''''''9 page 32 KSC-11437 CIRCUITS Acqu$IIOI"I pe1lOrmanc:es 01 OPSK camer Ifack.1OQ lOops page 55 NPQ.18166 Inventors: Be Safe, Not Sorry! 'Do ing Your Legal Homework On Technology Startups: a new white paper from one of the nation's leading patent attorneys, is filled w ith inside tips you need to know before setting out on your own. Send c heck or money o rder for $1 9.95 to: Arthur Lieberman 292 Madison Avenue. New Yo rk . NY 10017 (212) 532-4447 ImprOYed lefo-cr~ oet9Ctor page 40 NPOI8'15 COLLIMATORS Measurng soallllly vary 109 Iransmltance a a , ... page 66 NPOI8298 COMBUSTION CHAMBERS 0Iarr0er k:w tT'IICrogr8YIty COfTtlusl101"1 experlfl"lel'llS page 65 MSC 21777 COMPOSITE STRUCTURES AbsorPhon 01 cnJShlng energy ., square com postle ILCleS page 110 lAA 14343 COMPUTER GRAPHICS Software tor Pfoces5lng meIeOfotogcal dala page 80 GSCI3402 Software graptlICal user rllerlace lor anatysls 01 "-page 82 lAA-I'371 COMPUTERIZED SlMUUTlOH SynchrOflll8l101"1 a oar.1eI dtscrele evenI smuIa,,,,,,, page 129 NP().I841. CONNECTORS GuocIe"" __ '" electrical conneclCW page 123 MF&28582 boI wo..Nd O'IP rOJnd etectllcal COf'V'I8CkXS page 99 KSC11406 CONSEClITlVE EVENtS SynchrOflllal1Ol"l 01 parallel discrete 8'0'81"11 """"', .... page 129 NP().I8414 CONSTRAINTS FIlI8d Of conItoleo fY1CMIm8I"Itloocr8$l1aJl'll page 108 MSC21438 CONTROL STICKS ..tovs11Ck WIth cab6e spt'lI'IQSoIlefsbettefleei page 99 GSe13!87 COOLING SYSTEMS Ovecttnlertace. Iusbe .... ,- page 114 AfC.1I920 COUNTERSINKING PrecISe COUOI&fSM'lIung '001 page 128 GSC-13296 CRASttWORTHINESS Absorp(1OI"I of crustwlg energr ., SQ,Iaf8 com --- page 110 l.AA 14343 CROPS Sorbent-bed crop-O'V11"9 syslOm page 116 MF$.28567 CRYOSTAT'S VanabIe-~at ... e Cf)OSlaI lor flda~ damage Ie$IIOg 01 get mat'UTI detectors page 71 GSCI3439 CURING Curing a !algi COI'TlPO&Ile cyW1der WI!houI an aulOClave page 120 Nf'O.18195 CURVATURE Ad!u$tll"lQ curvalures of large m.rrors and lenses page 68 NP(). 18345 CYUNORtcAL BODIES CUrIOg a large eanposne cyfI"Ider Wltnoul an auIOC""" page 120 NP().18195 D DATA ACOUISfT1ON ScarIrq syslem ac- qull'es dala al designated COClurpoow PClAT/38b plu~-jn bo.lrd. )2K to 1M byle O-ws slall( memory, muillple PCS OJX'fahon. 5("51 option. Uwp(lon. U~ Hams RTX 2000. SC/FOx PCS)2 (Parallel Coprocessor System 32) 1 S MIPS to 70 MIPS, Men- " , .. llpvrlX)<,(> PC!AT/18b 12-bil plu~- jn bo .. ud with MK to 1M bylC O-ws "",'ilc m('m()r)'.Uses 12-bI' SC12 Fooh mlUoproc('Oi'iOf IdeO'll for(,nlbedded rE'JI~I'mc conl rol, dala JUIUISlhon. or h l~h-~ I>fOC- Official NASA CAPS Black cap with gold leaves and official NASA insignia . Only 59.95 each! -----------Please send (insert quantity) one-size-fits all NASA caps. Add $5.00 for handling and shipping charges. NY reSidents add sales tax to total. TOTAL Enclosed: $ Name Address ___________ _ City State ___ _ Zip ______ _ Mail payment to: Nasa Tech Briefs, Dept. F 41 East 42nd Street, Suite 921 New York, NY 10017 For credit card order call (212) 490-3999 An tnnovative Approach to Attaining "World Class Manufacturing Business Performance" Author Gunn puts for· ward a new nine·step approach to develop· ing and Implementing a future oriented manufacturing strat- egy. From the com- puter·integrated en· terprise to the open· ended quest for qual· ity, Gunn's program reflects a breadth of vision his experience has brought him. Only $28.00 plus $5.00 for shipping and handling. NY residents add sales tax to total. Mail your order to: NASA Tech Briefs, Dept. F, 41 East 42nd St., #921 New York, NY 10017 !1;ii:t~~;I~~;;~~n.~~~ (;15) 322-8763 208 California Ave., Palo Alto, CA 94306 For credit card order~ call (212) 490-3999 For More Information Circle No. 310 For More Information Circle No. 488 --1---- Record 2.2 Mbits/Second Data on Videocassette Designed for airborne and harsh environ· ments, the Merlin ME·981 Data Encoder formats PCM or MIL-STO· 1553 data for up to 2·hours continuous reo cording ( > 15 Gbits) on standard VCR formats. Merlin 1888 Embarcadero Road Palo Alto, California 94303 (415) 856-0900· FAX 415/858-2302 For More Information Circle No. 439 144 VGA TO VIDEO SCAN CONVERTER COCONurM _ Smallest, software-free scan converter available _ Converts VGA to Composite, RGB and S·Video _ Flicker-free _ NTSC, PAL & Universal AC Supply Standard _ Only $1595., 1 year warranty @] Communications l7l!DSQecialties, Inc. TEL: 516-273·0404 FAX: 516-273-1638 The fastest real time data and analYSIS systems for your PC can be found in our FREE catalog. We feature 50 .000 Hz throughpul to disk and display simultaneously. but see ing is believing. Order an Evaluation Kit. or call for complete information today. 1-800-553-9006 DATAQ INSTRUMENTS, INC. 150 Springside Drive. Suite B220 Akron.OH 44333 Tel (216) 668·1444 Fax (216) 666·5434 For More Information Circle No. 347 For More Information Circle No. 655 --~---------------------~ NASA Tech Briefs , September 1992 MARKETPLACE To Advertise-Call Airborne DAS Records Data on Videocassette o UJ o :; r- REAl---TiME NETWORk The SCRAM Net'" Network com- bines the real- time speed of replicated ME980!990 Data shared memory with the Acquisition Encoder! flexibility of a Decoder system com- bines 2000 to 590.000 data with fiber optic LAN composite video on standard VCR format. to get microsec- M I- ond response er In from multi-vendor computers. It offers distinct advantages in critical simulations. Brochure I highlights system's features. 1888 Embarcadero Road Systran Corp 4126 Linden Avenue Dayton Pato Atto, California 94303 OH 45432-3068 USA. " (415) 856-0900' FAX 415/858-23~ I Phone (513) 252-5601 or 1-800-252-5601. For More Information Circle No. ~or More Information Circle No. 432 FREE! 130 Page Catalog "Optics for Industry" Fre~ 130 page product catalog from Rolyn, world's largest supplier of "Off-the-Shelf" optics. 24-hour delivery of simple or compound lenses, filters, prisms, mirrors, beamsplitters, reticles, objectives, eyepieces plus thousands of other stock items. Rolyn also supplies custom prod- ucts and coatings in prototype or production quantities. ROL YN OPTICS Co., 706 Arrowgrand Circle, Covina, CA 91722-21 99, (818)915- 5707, FA)( (818)915-1379 For More Information Circle No. 411 For The Finest In WlRECWTH From 101010.000 Lineal Feel 110600 Mesh. We Can Supply You W,lh The Hlghesl Dualily PreciSion Mesh Wife CIOlh • Stainless Steel • Monel • Copper • Aluminum • Titanium • Galvanized • Brass • Nickel • Tungsten • Niobium • Incoloy 'Inconel • Steel • Hastelloy • Nichrome CALL FOR FREE ESTlMA TE AND BROCHURE HIOO-63HI490 FAX: (201) 759-1067 • D"ecl sensor 10 R5-232C/RS-485 • Digital output in engineering units • Dlgilal 110 lor solid Slale relays • Digital limits and alarm capability • Simple ASCII commands • Small size fits in a lhermowell ~~~§ ~,~ (603) 622-0452 For More Information Circle No. 382 INlELUGENT DATA ACQUISITION ..... I_~ ........ tI_ ·,.,-1oa •• I I iiii' I JI __ : Now you can run high speed data acquisition under WindowsT .. . A Data Acquisition ProcessorT" with on-board intelligence handles the critical part of an application : the tasks that run in realtime. The DAP can be con trolled from any Windows language or application that can make DLL calls . 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September 1992 Flexible Frame Grabber For The PCI AT • 8 to 8000 pixels per Une • 2 to 40 MHz sampling/display rate • 2 to 1020 lines per field • 1 Cl( 4 Mbytes of Reconflgurable Image Memory • StandardlNonstandard V1deo AoqulSidon • 6 Input VIdeo Muldplexer • CT, MR video capture • Interface to hlgh-resoludon CCO cameras • Extensivs libraries and menu driven software ®EPIX· 3005 MacArthur Blvd., Northbrook, IL 60062 708-498-4002 FAX: 708-498-43~ FL;~;;pi;;tetN;;: I ' Infinite Length Plots on Plain Fanfold Paper ' 300 OPI Resolution laser Electrophotography -2.9 Inches Per Second Plot Speed -Centronics Compatible Interface Capable of Continuously Plotting 274K Bytes Per Second ' Use as a Raster Transfer Plotter or as a High Speed (16 PPM) PCl4 Compatible Printer ' Form Overlay and Vector Graphics Commands ' Ideal for Telemetry and Medical Strip Charts ' low Operating Cost Per Page ' Perfect Replacement for Electrostatic Plotters JEgis Engineering, Inc. 8133 Leesburg Pike, Suite 780 (703) 847-2013 Vienna. VA 22182 Fax: (703) 760-0840 For More Information Circle No. 414 Instant Microcontroller Instant C Programming 00n1 usea microprocessor, usea SmartBlock'" microcontroller module to build your custom controller. Our $195 interactive Dynamic ClM development system makes programming easy. 3.5 x 2.5 inch module includes microprocessor, memory, bmeldate clock. eeprom. watchdog, serial ports and more. As low as $59 in quantity. The efficiency of a custom design without the headaches. Z-World Engineering 1724 Picasso Ave., Oavis, CA 95616 USA Tel: (916) 757-3737 Regular Fax: (916) 753-5141 Automatic Fax: (916)-753-0618 (Call from your lax, request data sheet #14.) For More Information Circle No. 519 145 Subject Index (Continued from page 142) A calendar featuring each month breath- taking four-color photographs of the space shuttle in action! Dates and space launches from the 1960s to present in- cluded. Printed on deluxe coated stock with laminated colorful covers. Only $10.95. ----------Send ___ NASA Calendar(s) at $10.95 each. Add $5.00 for shipping and handling charges. Orders from $51 .00 to $100.00 add Shipping and handling charge $8.SO (NY residenls add sales tax 10 lotal) TOTAL ENCLOSED $ _____ _ Name ________________________ _ Company ____________________ _ Address ____________________ _ City/StatelZip _________ _ Mail to: NASA Tech Briefs, Dept. F, 41 East 42nd St., # 921 New York, New York 10017 For credit card orders call (212) 490-3999 ElECfROFORMING f~tePIII'oI _ uncomoctod - paoe 12" UfS29828 ElECTRON EMISSION O1argeUES ~lesaldr~oI deleCts 110m castw'lgS .-126 t.4FS-29838 FREOUENCY STAHDARDS AIcmc clOCk based 01 IIneaf JOnltap ...... NP(}l8382 ~0Ied leI'CH:IOSSItIg deleclO> ooge 4() NP().t84IS fRICTION H'\tIleJTl)eralute 1'CX)metef and dala acoJISIhon syslem page 60 lEW.~ G GAMMA RAYS ..... -monochromator b' hard • rays and 1 lays page 58 t.4FS26497 Yarl3bletefT'4)efature Cf)'O$tal Jot radlahon- damage testtng 01 ger manoum deIecIo>. ..... " GSCI3439 GAS TUNGSTEN ARC WELDING Oleapee CUSlem Shielding cups lOr ate ..-... page 118 MFS29B15 Canpact Ihf~ the- IOrCh '01$0\ SYSIem page 118 MfS.29811 lDngsu page 111 J«:,12637 HUMAN FACTORS In recephon 01 \eIemeIry NK:KEl AU.O"rS ENGINEERING page 56 NP()18290 Awctal1~lOrng ElecUobrTwIg 1epiM' a SyStem am dIsPaV ~Ioco>"""""'01 -..-.""""""", ,-'2 LAR 14049 frequency In BPSK '-' .-42 Nf'O-I3<36 ..... \24 MFS29828 HYPERGOUC ROCKET _01_ NUMERtcAL PROPELlAHTS da&a lra'1llltlOn-l1ac:b-lg The CONTROl f'4UId CO'T1)atlOte Wlih _56 NPOt8176 ~atIl'lgSYSMmIOf """" .... r ...... neflcaly CCInIroied .-11 K$;.11389 M -...-.-81 GSC 13366 MACHINING 0 ~_b IMAGE ANALYSIS ~calyc::omoled llerat....e Bayes.an -- o RING SEALS claSSlhcabon In DOgO 81 GSCI3366 floallng rng.groove poiatmetuc SAA ...... ..... 129 NP().I8n IlAGNElOACOOSTlCS ..... 122 MFS29749 SoItwafe Qtarhcal U5ef Measufement 01 resdJal I'lteftace b anaIVM a suess In .erromagnebC: OPERATING SYSTEMS ""- .......... (COMPUTERS! .-82 lAA14371 .-62 lAA-14239 Operallng syslem lor ' ...... nencaly oontJoIed IMAGE PROCESSING MAlNTENAHCE -- ..... 81 GSCI3366 ClaSSlhcallOl'lOlIand EIBcIrt*:lrrTW'lg repa. a co.g ~\ch ertef'l'lln S()Jare com- page 101 t.4 fS-28591 P ...... 1.-page 110 LAR 14343 MEDtCAl EQUIPMENT INFRARED ~"""""'Y"- PARALLEL PROCESS grasps smaI obtects ING (COMPUTERS) DETECTORS pogo 134 GSCI3306 DeIIetopIng a NiMef -CharrOer b' lestng ., ~algol'ltrynb Irared I'T'Ia9'"O delec10rs MERCURY ISOTOPES ""-............ """"" NP().I8Ce9 Four-sectof cyIIrOlCaI page III AACl2637 INFRAAED RADiATlON radlo-treQuenCy IOf'l trap SynctvlTlllallOn 01 Cienefallllg laNnilarec! page 64 NPOI6335 parallel dlsclele even! radiallOf'l by two-wave smulatlOl"lS """"'" METAL HALIDES page 129 NP().I8414 page 31 NPOI8344 FaorcatlOf'l 01 metal CIlb .... cathodes by PHASE MODULATION INSERTS ......... NPO,8118 BehaYo 01 Co6las loop Shunk 'II SOk8'atlte "" page 16 '" recephon 01 lelemetry 5el'ts seal henne(lcally .-56 NPOI8290 page 127 /lJC..11690 METAL OXIDES EHeeI 01 Phase un Ar'TtMenI·t~alure balance 11"1 ptOWCI INSTRUMENT spull!fll'lg 01 COf'f1)OSlie """"""0< PACKAGES """"Ions page 57 NP().I8293 bwed ar1lCUated hous .-125 NPOI8221 .... b_ METEOROlDGtCAl PHASE SHIFT KEYING ............... ~1Of'I perb'mances .-10 NP().17656 PARAMETERS 01 OPSK carnenrackng Software klr proc;:e$SIf'9 "-INTERFEROMETERS tneleoro6oglCal dala ..... 55 NP018166 Study "_sed(l!> -'" GSCI3402 lall ''lIerfetometef ()peo.1oop acQlM:$Ihon 01 page 14 NP018193 METEOROlOGY IIeq..oency 11"1 BPSK McrOWirVe remote seos page 42 NPOI8436 INTERFEROMETRY ng 01 rneworoklglcal CJpen.1oop acq.JI$ItJOn 01 Pn"ecfed.111fI08, phase:o ~lIIes S\Q:lI'essed calfe 51epp!ng proI'llometer DOgO 12 NPOIIIl22 - page 51 LEW '.996 page 48 NPOI8364 MICROWAVE toN TRAPS RADfOMETERS PHOTOELECTRON (lNSTRUMENTATtoN) MlCfowave remote sens SPECTROSCOPY Aaomr: clock based 0'1 1'19 01 meteOfOOglcal Reformawng data Irem 1Inea'lOI1ttap (JJ8flI111eS l(ray~trO'l ..... 46 Nf'O-'8382 .-12 NPOI8022 spec."""""" """"", LEW '.993 Four secklr cyWOcal MICROWAVE TUBES racio-Irequency IOn trap Co..(JIerk:avItytrao.oel!ng PHOTOMETERS .-64 Nf'O-I83J5 w.we tt.Oe has phase- Soec.........."... dele<; "",,-<1I!d_ lOt array WI1h ntegrated L .-26 lEW·'4989 Idler page 127 NP().18317 MILLING (MACHINING) lAND USE ()peIal.t"19 sysJem lor PSYCHOPHYSJCS 0assd1Ca11On 01 land I"lUTIefcally conIrOlIeO Systema,1C disturbance cover lrom aerbotne MSS _mac:..... of opIrnai rotallCNl cia .. oage 81 GSCI3366 lraf9CkWY .-68 ARC '2688 .- 100 AAC12700 MIRRORS LATCHES Ad!USIII"9 curvatures 01 PHYSICAL EXERCISe Manual CMlfrlde tot eIec 18'98 mwlOl'S and lenSeS Effects 01 exercISe WfI"lQ tromechanllCal latch .... 68 NPOI83450 prOkInged bed fest page 117 GSCI3383 ..... 136 AFC-12100 Se/I.a1/grw'9 cr..., MODULAlORS - Ellecl 01 Chase un- POlARIMETRY oage 101 MFS28591 balance In prOWct lter.1l1'oE 8ayesen .......... el.asslllCa.tlOO 11"1 LEAD ACID BATTERIES paqe 507 NP().I8293 po&arrnel:rtt SAR Cooing of 1'l'lOkied oat ooge 129 NPOI8308 lery 5Wstfales MOLDING MATERIALS PoIarrnetflC ladar oage '26 Np()'t8236 Cootll'"l9 01 molded bat SIgIlatUfes 01 frOlen and lery Si..b.lrates '!\awed leresIS oage 126 NP().l8236 page 13 NP()I8280 NASA Tech Briefs, September 1992 ADVERTISERS INDEX AcademIC Press. Inc AOMAX Computer. Inc AEQIS Engmeenng. Inc Aerospace OptICS, Inc . _ ••• m~~~=r Crtems• Inc Amco Engoneenng Company Amtec EnglOeenng. Inc Apex MoctOIochnoiogy CO
n' The MathWorks. Inc ... Tosh~ba InformaUon & Imagll1g Technologi8S Group TRANTER, Inc Velmex. Inc . _ .. Venture CommunlC8hons ........ (RAC 499) . .. .... 8' :::: l~~g ~l :... . ...... . ;g ...... !RAC4484. 5) 55.73 .... .. RAC 402) ............. . .. . 03 ..... RAC 467.469.479) '0.56.57 (RAC 411) 14'\ ! RAC 517j ................. .. 54 ~~g ~! :::::::::.:: . ~~ RAC4.9) .............. '23 !RAC 632.637) .... '1 .38-39 RAC 609.6'2) . .. 5 RAC 445) ............. 4' ... (RAC44~ " .. .. . RACSO . .. ..... !RAC503 .. .... lRAC432 .. (RAC 62 .. '::: i:g~f . 104 .. .. !. 2 ~ . ,. 52 • .45 .. ...... 6' .... .... 83-98 ........ . 70 ...... 22-23 ..... (RAC 558) ................ cov \I .... !RAC 594) ..... .. ........ 13 . RAC 396) .. '08 InternatIOnal. Inc ... . .. (ARAACC 4 30 05 5 ) ....• 128 ~~;.~r~e:'rCh. i;,c" .... !RAC 4851 ::::::::::::::"cov 1~ Zero PlastICS .......... . ..... (RAe 535~ 76 rw~:[~::~~ :'::: i:g ~~) ~:~ ' RAC stands for Reader Action Card. For further information on these advertisers, please circle the RAC number on the Reader Action Card in this issue.This index has been compiled as a service to our readers and advertisers. Every precaution is taken to in- sure its accuracy, but the publisher assumes no liabili for errors or omissions. POl'J'CARBOHATES e.a .. 1otIIv stre!Ched ~Iel*"b caDiICOIOyong sysoem page 116 flAfS.28567 SPACE FUGHT STRESS GriW'ly_ caicUn. and bone update 1989 Pi96 136 AACI2717 SPACEBORNE ASTRONOMY Study 04 space--based op. IcallOler!efometer page 74 NP().18193 SPECTROMETERS $pectu.JlTHrnagtflg delec tot anay WIth wuegrsled Idler page 121 Nf'O.l6317 SPECTROSCOPY Qo.arge-carrlf!r.sr;;altetlf'9 spec1fOSCopy WIU1 BEEM page 58 NP().I8411 SPECTRUM ANAlYSIS ElnwlalWlg tMS 1"1 acouslOoq)lICall spectn.m - cage SO NPQ.18275 ~1M!ddlgltaJsoec Irum analyZer page S4 NPO-ln59 SPUTTERING A.n'i>ieol temperature SPUlleflng 01 cOfTlX)Stle 0It1de l*ns page 125 NPOI8221 STIRUNG ENGINES Modular heat ea::1'Ia.ngef WIth Integral heal p.pe page tOO lEW 15008 STRAIN GAGES R:M:t Sttalr'l gauges lor high teI'fl)efatures Pilot n lEW 15079 STRESS MEASUREMENT Measuremenl 04 resQ.IaJ stress III IefranagnetlC malerl3ls page 62 lAA-14239 SUPE1'COMPUTERS ~aN3'IIeI StOkes algOfllMl lor super~lers page 111 AAC-12637 SUPERCONDUCTORS Pretormed supetconclJC· I ........... page 121 1AR 14395 SUPERSONfC AIR FOILS NaMa/flow WI'lQ page 105 LAR-14281 SUPERSONfC WINO TUNNELS Water-cooled IOtaJ. lempefalure prObe page 109 LAA-14.435 SURGES Fataciay cage protects -Ioghtnong I*}f! 32 KS(;. 11437 SURGICAL INSTRUMENTS ~.. gr~ sma_ ootects page 134 GSCI3306 SYNTHETfC APERTURE RADAR netatl\'8Ba~ CiassllcallOO l"I POIarmelrc SAR page 129 NPOI8308 RJtar~llC radilr SIQOiIIUfes ci frozen and lhawea forests page 73 NPQ.l8280 T TELEMETRY Behavor 01 Canas lOop 1"1 re::::eptlOO 01 telemetry page 56 NP().I8290 TEMPERATURE PROBES Water-cooled ICQI tempefl'lJfe prot:le page 109 LAA-14435 TEMPLATES ~tesal(trer'nOllalol detects 'rom CISIIflgS oage '26 MFS-29838 TEST CHAM BERS AImond·Shaped lest body page 32 1AR·13747 Ch/tnt)eriorlestlflg" 'rared IIT\aglng deleclOrS page 71 NPOID9 THER MAL ABSORPTION o.ecl w WEAR Hlghlemperalure llibomeler and dala acQuISItion system pege 60 lEW 15362 WBGHTLESSNESS QaYffy catcLm, and bane lCldate 1989 page 136 AR: 12717 WElDING e>e_ CUSICm ShIekiIng c~foralc ........ page 118 flAF5-29615 WtNG lDA OtNG NalUfal.11ow WW"Ig page lOS lAA ' 4281 x X RAY SPECTROSCOPY AebmalllOQ data lro-n )( lay pho(oek!ctrorl speclrClSCOPV page 80 lEW 14993 X RAYS ...... ...,.. monoctwomalOf lOr hard )( lays anc2) rays page 58 flAFS28497 Classified advertising rates and specif ications are as follows: Set in 6 point light type face, with up to five words at beginning of copy in bold caps . Count box numbers as six words. 50 words or less ................. ........ ............ $ 240.00 Over 50 words each additional word .. .. ........ 2.10 Bold Face words ............ ...... .... ........ ............. 3.40 Check or money order must accompany order to: Classified Advertising Manager, NASA Tech Briefs, Suite 921 , 41 East 42nd Street, New York, NY 10017-5391 TECHNOLOGY WANTED Public Transportation Research Group seeks innovative technology to improve the efficiency 01 rait car and transit bus maintenance operalions. Advanced technologies such as robotics and automated test procedures must be proven and cost -effective. InqUIries may be direcled to: T ransportation Development Corporation. 1201 New York Ave. N .W .. W ashington, ~C . 20005 NASA Tech Broels, ISSN 0145-3.9X. USPS 750-070. copyrighl C . 992 In U .S .• is published monthly by AssOC18led Business Publications Co .• ltd .. 41 E. 42nd Sl. , New York, NY .00.7-5391. The copynghled Information does not Include the (U.S. nghts to) individual t9ch briefs whICh are supplied by NASA. EdItOrial, sales, productIOn and CIrculatIon offices at 41 East 42nd Street, New York, NY 10017-5391 . SubSCription lornon..qualilledsubscnbers In the U.S. , Panama Canal Zone, and Puerto RICO, $75.00 for 1 year; $125.00 lor2 years ; $2oo.oolor3 years. Single coplesSI 0.00. Foreign subscnptlons one-year U .S. Funds $150.00 Remit by check, drah. postal, express orders or VISA. MasterCard. and Amencan Express. Other remtHances at sender's rtsk . Address aU communications for subscnptlons or CIrculation to NASA Tech Bnets, 4. Easl42nd Sireel. New YOrl<, NY 10017-539. Second-class poSlage pald., New YOrl< , NY and addItiOnal maIling offices. POSTMASTER: p lea se send address changes to NASA Tech Brief ., 41 East 42nd Street, Suite 921 , Ne w York, NY 10017-5391 J ackTM is skinny and not especially handsome, but he's one of the hot-test models working today. An off- spring of the University of Pennsylva- nia, Jack is a powerful human factors design and ergonomics visualization software package that provides a 3D human model for predicting how a per- son will interact with a given system or environment. Jack can help determine whether a human would fit comfortably in a system, have adequate field-of- vision, and be both able to reach the controls and strong enough to operate them. Sy using the simulated human to explore design alternatives while still at a CAD workstation, engineers can re- duce the need to build costly and time- consuming prototypes. With Jack, analyses formerly and painstakingly accomplished with blue- prints, databases, and small plastic fig- ures have graduated to dynamic 3D modeling. "Jack can model environ- ments as diverse as the space shuttle, a submarine, or a tractor," said Dr. Norman Sadler, head of University of Pennsylvania's Department of Com- puter and Information Science. "And we continue to develop it with an eye toward extensibility." John Deere & Co. recently used Jack for visibility and body sizing during development of an earth- moving vehicle , and other industrial customers are applying it to control room access. "Any human-machine in- terface is fair game for Jack," said Sadler. The model's body consists of 39 segments, 38 joints, and 88 degrees of freedom, including a 17 -segment flex- 148 ible torso, while fully-articulated hands add 30 segments, 30 joints, and 33 degrees of freedom. All parts are pro- grammed to move automatically in re- sponse to commands from a standard three-button mouse and pop-up menus. Simple mouse movements allow the user to view Jack from any distance or perspective, and a window on the screen shows the view from Jack's vantage point. The user has access to as many "Jacks" as needed, which can be con- figured to the proportions and abilities of many different people. "Jack's greatest asset is its extraor- dinary interactivity," said Sadler. "It's as easy for an engineer to manipulate Jack as his CAD model." According to Sadler, the average user can operate Jack after two days of training. Currently configured for Silicon Multiple Jacks can be used to analyze mUlti-person environments. Through the technology transfer process many of the systems, methods, and . products pioneered by NASA are reapplied in the private sector, obviating duplicate research and making a broad range of new products and services available to the public. Jack, a 3D human model, enables human factors analyses of cockpit and other computer-aided designs. Graphics IRIS 40 and INDIGO work- stations, additional versions of Jack are being developed for ISM RS/6000 and X-Windows-compatible systems. The software can work alone or interface with a variety of CAD systems, includ- ingAutoCAD, SDRC I-DEAS, MultiGen, Pro/Engineering, and SRL-CAD. Jack is the product of research dat- ing back to the late 1970s. NASA's Johnson Space Center (JSC) was the initial investor in the program. "We also gave Jack its first real-world problems to solve," said James Maida, director of JSC's Graphics Analysis Facility. Jack's earliest tasks addressed reach and vis- ibility, later extending to strength mod- eling and collision avoidance. Other major supporters of the program in- clude the Army Research Office and Army Human Engineering Laboratory. University of Pennsylvania scientists are working to realize Johnson research- ers' rec.ommendation of a natural lan- guage interface. "Within five years," said Sadler, "we expect Jack to be responding to verbal English com- mands." JSC functions as a co-researcher toward advancement of the computer science behind such models, returning data to the University of Pennsylvania for use in the next version of Jack. Other contributors include a team at Ames Research Center that has incorporated Jack into MIDAS (Man-machine Inte- gration Design and Analysis) , a human factors CAE system, in which he repre- sents a helicopter crewmember. ''The ultimate goal," said Maida, "is a human model exhibiting motion , strength, hearing, voice, and even some cognitive skills." 0 For more information about the technology described in this article, contact: David P. Harding, University of Pennsylvania, Suite 300, 3700 Market Street, Philadelphia, PA 19104; (215) 898-9585. NASA Tech Briefs, September 1992 I admit, when I first read about Mathe- Lynn Purser Orbital Dynamics f lnalyst Huntsville, f lfabama Working on ASA projects, I Now I use Mathematica regularly. matica, I was a little skeptical. I guess have to solve problems and present my I don't think it will ever replace mathe- mathematicians are like anybody else. Sort of like auto workers being replaced others can by robots-some mathematicians were un d e r- skeptical of something that might re- s tan d . place them. So when my firm offered P e 0 pie an in-house training seminar on Mathe- respond to a matica, I decided to see what all the talk was about. than abstract equations, hand- waving, or scribbling on a blackboard. With Mathematica's graphical capability, especially maticians; it acts as an assistant of sorts. It helps you explore and de- velop concepts, by handling the tedious details. In that way, you' re free to concentrate on anima tion, I can make adynamic Intersection of fields of sweep of two sensors in presentation that give a concrete idea the shunle payload bay. of what I'm talking about. Mathemotica is available for: MS-DOS, Then there's the symbolic power. Microsoft Windows, Macintosh, CONVEX, That class was fun. I tried to do For example, the first project I tackled DG AViiON, DEC VAX (ULTRIX and things beyond what the teacher was cov- with Mathematica involved a nasty alge- VMS) , DEC RISC, HP 9000, HP Apollo, ering-the rudimentary stuff about braic equation. I solved it on my own IBM RISC System/6000 , MIPS , NeXT, Mathematica syntax. I wanted to do ani- and then let Mathematica solve it. We Silicon Graphics, Sony, SUI1-3 , and SPARC- mation and play with the graphics. I was both came up with the same answer. stations. taken with the visual dimension of it. But my solution took a few hours and Prices ill U.S. and Canada start at $595. Mathematica's took a few minutes. Educational discounts are available . Simulations of the dynamics of the shuttle. Orders: 1-800-441-MATH Mathematicae2.0 The Standard for Technical Computing ~:=:'M~~::~-=-~=~~TKI'l.1rI: Wolfram Research. Inc .• 100 Trade Center Drive, ChampaIgn, Il61B20-7237 , USA 1 (2 1713980100, fax 1(2171398 0747. email mfoCwn com .. _ ..... __ .. _~ __ -......... Wolfrom R .... rch (UKI Ud., P a 80' 114. Abmgdon. 0"", OXI3 6TG, United KIngdom; t44(235) S50 440. fa,' t44(235) S50 445, amot! mf .. ukCwri.com For More Information Circle No. 485

NASA Tech Briefs, September 1992

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