420 research outputs found

    Magnetic Suspension and Balance Systems: A Comprehensive, Annotated Bibliography

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    This bibliography contains 301 entries. Results are reported of recent studies aimed at increasing the research capabilities of magnetic suspension and balance systems; e.g., increasing force and torque capability, increasing angle of attack capability, and increasing overall system reliability. The problem is addressed of scaling from the relatively small size of existing systems to much larger sizes. The purpose of the bibliography is to provide an up-to-date list of publications that might be helpful to persons interested in magnetic suspension and balance systems for use in wind tunnels. The arrangement is generally chronological by date of presentation. However, papers presented at conferences or meetings are placed under dates of presentation. The numbers assigned to many of the citations have been changed from those used in the previous bibliography. This has been done in order to allow outdated citations to be removed and some recently discovered older works to be included in their proper chronological order. Author, source, and subject indexes are included in order to increase the usefulness of this compilation

    Feasibility analysis of gravitational experiments in space

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    Experiments on gravitation and general relativity suggested by different workers in the past ten or more years are reviewed, their feasibility examined, and the advantages of performing them in space were studied. The experiments include: (1) the gyro relativity experiment; (2) experiments to test the equivalence of gravitational and inertial mass; (3) an experiment to look for nongeodesic motion of spinning bodies in orbit around the earth; (4) experiments to look for changes of the gravitational constant G with time; (5) a variety of suggestions; laboratory tests of experimental gravity; and (6) gravitational wave experiments

    To perform a gyro test of general relativity in a satellite and develop associated control technology

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    A satellite configuration having two gyroscopes with axes parallel to the boresight of a telescope and two at right angles to the telescope and approximately parallel and perpendicular to the earth's axis is proposed for measuring geodetic precessions due to the earth's motion about the sun, higher order geodetic terms calculated from the earth's quadrapole mass moment (0.010 arc-sec/year in a 400 nautical mile polar orbit), and deflection by the sun of the starlight signal for the reference telescope. Data from the experiment also contain large periodic signals due to the annual and orbital aberrations of starlight which are useful in providing a built in reference signal of known amplitude for scaling the relativity signals, and should yield a singularly precise measurement of the parallax of the reference star. The development of the gyroscope and its readout system are discussed, as well as signal integration, drag-free control, and attitude control

    Gravity Probe-B: the Stanford General Relativity Experiment as a Shuttle Payload

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    Gravity Probe-B (GP-B) is an experiment under Phase B study at Marshall Space Flight Center which is designed to measure general relativistic induced torques on a gyroscope in orbit about the earth. The measurement of the relativistic effects requires that the gyror scope be nearly perfect in spherical shape and be shielded from the influences of nonre! ati vis tic effects. To accomplish these requirements, the spacecraft design includes provisions for superconducting magnetic shields, superconducting readout electonics, drag free gyro suspension, a drag free spacecraft, and provision for gyroscope spin-up at cryogenic temperatures. The spherical rotor fabrication has resulted in advances in manufacturing and measurement techniques in order to meet the experiment requirements. An essential feature of the spacecraft system which will be launched by the Shuttle is a large volume liquid helium dewar which will supply cooling to maintain the gyros and shields at a few degrees kelvin for over a one year duration. The helium which is boiled off is used to maintain drag free control of the spacecraft. This paper will discuss the design requirements for the experiment, the essential features of the proposed spacecraft, the gyro manufacturing technology, the gas spin-up method, and the liquid helium technology

    The cryogenic gyroscope program at Jet Propulsion Laboratory Final report

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    Cryogenic gyroscope with spinning superconducting sphere levitated in vacuum by magnetic fiel

    Superconducting gyroscope research

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    Four basic areas of research and development of superconducting gyroscopes are studied. Chapter 1 studies the analysis of a SQUID readout for a superconducting gyroscope. Chapter 2 studies the dependence of spin-up torque on channel and gas properties. Chapter 3 studies the theory of super fluid plug operation. And chapter 4 studies the gyro rotor and housing manufacture

    Superconducting bearings for application in cryogenic experiments in space

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    Linear superconducting magnetic bearings suitable for use in a proposed orbital equivalence principle experiment and for general application in space were developed and tested. Current flows in opposite directions in adjacent superconducting wires arranged parallel to the axis of a cylinder. This configuration provides maximum stiffness radially while allowing the test mass to move freely along the cylinder axis. In a space application, the wires are extended to cover the entire perimeter of the cylinder: for the earth-based tests it was desirable to use only the bottom half. Control of the axial position of the test mass is by small control coils which may be positioned inside or outside the main bearing. The design is suitable for application to other geometries where maximum stiffness is desired. A working model scaled to operate in a 1-g environment was perfected approximate solutions for the bearings were developed. A superconducting transformer method of charging the magnets for the bearing, and a position detector based on a SQUID magnetometer and associated superconducting circuit were also investigated

    Magnetic Suspension and Balance Systems: A Selected, Annotated Bibliography

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    This publication, containing 206 entries, supersedes an earlier bibliography, NASA TM-80225 (April 1980). Citations for 18 documents have been added in this updated version. Most of the additions report results of recent studies aimed at increasing the research capabilities of magnetic suspension and balance systems, e.g., increasing force and torque capability, increasing angle of attack capability, and increasing overall system reliability. Some of the additions address the problem of scaling from the relatively small size of existing systems to much larger sizes. The purpose of this bibliography is to provide an up-to-date list of publications that might be helpful to persons interested in magnetic suspension and balance systems for use in wind tunnels. The arrangement is generally chronological by date of publication. However, papers presented at conferences or meetings are placed under dates of presentation. The numbers assigned to many of the citations have been changed from those used in the previous bibliography. This has been done in order to allow outdated citations to be removed and some recently discovered older works to be included in their proper chronological order

    Basic principles of unconventional gyros

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    Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1964.MICROFICHE COPY AVAILABLE IN AERO.Includes bibliographical references (leaves 115-119).by Derek Howard Baker, James Weatherspoon Harrill.M.S
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