31,981 research outputs found

    The NASA SBIR product catalog

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    The purpose of this catalog is to assist small business firms in making the community aware of products emerging from their efforts in the Small Business Innovation Research (SBIR) program. It contains descriptions of some products that have advanced into Phase 3 and others that are identified as prospective products. Both lists of products in this catalog are based on information supplied by NASA SBIR contractors in responding to an invitation to be represented in this document. Generally, all products suggested by the small firms were included in order to meet the goals of information exchange for SBIR results. Of the 444 SBIR contractors NASA queried, 137 provided information on 219 products. The catalog presents the product information in the technology areas listed in the table of contents. Within each area, the products are listed in alphabetical order by product name and are given identifying numbers. Also included is an alphabetical listing of the companies that have products described. This listing cross-references the product list and provides information on the business activity of each firm. In addition, there are three indexes: one a list of firms by states, one that lists the products according to NASA Centers that managed the SBIR projects, and one that lists the products by the relevant Technical Topics utilized in NASA's annual program solicitation under which each SBIR project was selected

    LARES-lab: a thermovacuum facility for research and e-learning. Tests of LARES satellite components and small payloads for e-learning

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    LARES, an Italian Space Agency satellite, has been launched successfully in 2012. A small thermovacuum facility has been designed and built specifically for performing tests on the optical components of the satellite. Due to the extremely demanding performances of the optical cube corner reflectors, the space conditions have been simulated using the most up-to-date technology available. In particular Sun, Earth and deep space can be simulated in a ultra high vacuum. It is planned to automate the facility so that it can be operated remotely over the internet. The students during the lectures and the researchers from home will be able to perform thermal tests on specimens by exposing them, for specified amount of time, toward Earth, Sun or deep space. They will collect pressures and temperatures and will input additional thermal power through resistive heaters. The paper will first describe the facility and its capabilities showing the tests performed on LARES satellite components but will focus mainly to the planned upgrades that improve its remote use both for research and e-learning

    Reduced-Order Modelling of the Bending of an Array of Torsional Micromirrors

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    Reduced-Order Modelling of the Bending of an Array of An array of micromirrors for beam steering optical switching has been designed in a thick polysilicon technology. A novel semi-analytical method to calculate the static characteristics of the micromirrors by taking into account the flexural deformation of the structure is presented. The results are compared with 3D coupled-field FEM simulation.Comment: Submitted on behalf of TIMA Editions (http://irevues.inist.fr/tima-editions

    Small business innovation research. Abstracts of completed 1987 phase 1 projects

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    Non-proprietary summaries of Phase 1 Small Business Innovation Research (SBIR) projects supported by NASA in the 1987 program year are given. Work in the areas of aeronautical propulsion, aerodynamics, acoustics, aircraft systems, materials and structures, teleoperators and robotics, computer sciences, information systems, spacecraft systems, spacecraft power supplies, spacecraft propulsion, bioastronautics, satellite communication, and space processing are covered

    An optofluidic router in a low-cost (PDMS) platform for rapid parallel sample analysis

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    En col·laboració amb la Universitat de Barcelona (UB), la Universitat Autònoma de Barcelona (UAB) i l'Institut de Ciències Fotòniques (ICFO)Optofluidic system for (bio)chemical applications are becoming more demanding in terms of num- ber of control points, number of light sources and readout equipment. So far, most of these sys- tems require several light sources/detectors for suitable performance, increasing their complexity and cost. In this work, we present an easily integrated, fluidically controlled optical router that fa- cilitates coupling of several light sources or detectors. By using PDMS mirrors and phaseguides, the switching liquid is guided and pinned in desired angles, so that the incident light undergoes total internal reflection and can be reflected towards the output channels without any movable parts. The developed router presents ideal performance for lab on a chip applications, achieving switching frequencies between 0.07 ± 0.025 and 4 ± 2 Hz, depending on the flow rate of the switching liquid. The cross-talk levels are at 20 dB from channel output power to static noise level. With the use of parabolic mirrors, channel coupling efficiencies decrease just 2.38 dBm over four channels. The dynamic switching noise reduces the cross-talk levels by 2-5 dB, depending on the incorporation of ink-apertures. The insertion loss of these devices ranges from 17.34 to 25.42 dB. These results prove the viability of the fluidically controlled router in the low-cost PDMS platform. The intended goal of this work has been to simplify and speed up parallel sample analysis with the router integrated into a multiple path photonic component on a single chip. Development on this front is ongoing to rapidly measure methadone concentrations on chip

    Improved micro-contact resistance model that considers material deformation, electron transport and thin film characteristics

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    This paper reports on an improved analytic model forpredicting micro-contact resistance needed for designing microelectro-mechanical systems (MEMS) switches. The originalmodel had two primary considerations: 1) contact materialdeformation (i.e. elastic, plastic, or elastic-plastic) and 2) effectivecontact area radius. The model also assumed that individual aspotswere close together and that their interactions weredependent on each other which led to using the single effective aspotcontact area model. This single effective area model wasused to determine specific electron transport regions (i.e. ballistic,quasi-ballistic, or diffusive) by comparing the effective radius andthe mean free path of an electron. Using this model required thatmicro-switch contact materials be deposited, during devicefabrication, with processes ensuring low surface roughness values(i.e. sputtered films). Sputtered thin film electric contacts,however, do not behave like bulk materials and the effects of thinfilm contacts and spreading resistance must be considered. Theimproved micro-contact resistance model accounts for the twoprimary considerations above, as well as, using thin film,sputtered, electric contact

    Design, fabrication, and testing of silicon microgimbals for super-compact rigid disk drives

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    This paper documents results related to design optimization, fabrication process refinement, and micron-level static/dynamic testing of silicon micromachined microgimbals that have applications in super-compact computer disk drives as well as many other engineering applications of microstructures and microactuators requiring significant out-of-plane motions. The objective of the optimization effort is to increase the in-plane to out-of-plane stiffness ratio in order to maximize compliance and servo bandwidth and to increase the displacement to strain ratio to maximize the shock resistance of the microgimbals, while that of the process modification effort is to simplify in order to reduce manufacturing cost. The testing effort is to characterize both the static and dynamic performance using precision instrumentation in order to compare various prototype designs

    Performance of the Birmingham Solar-Oscillations Network (BiSON)

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    The Birmingham Solar-Oscillations Network (BiSON) has been operating with a full complement of six stations since 1992. Over 20 years later, we look back on the network history. The meta-data from the sites have been analysed to assess performance in terms of site insolation, with a brief look at the challenges that have been encountered over the years. We explain how the international community can gain easy access to the ever-growing dataset produced by the network, and finally look to the future of the network and the potential impact of nearly 25 years of technology miniaturisation.Comment: 31 pages, 19 figures. Accepted by Solar Physics: 2015 October 20. First online: 2015 December 7. Open Acces

    A Survey of the Spacecraft Line-Of-Sight Jitter Problem

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    Predicting, managing, controlling, and testing spacecraft Line-of-Sight (LoS) jit- ter due to on-board internal disturbance sources is a challenging multi- disciplinary systems engineering problem, especially for those observatories hosting extremely sensitive optical sensor payloads with stringent requirements on allowable LoS jitter. Some specific spacecraft jitter engineering challenges will be introduced and described in this survey paper. Illustrative examples of missions where dynamic interactions have to be addressed to satisfy demanding payload instrument LoS jitter requirements will be provided. Some lessons learned and a set of recommended rules of thumb are also presented to provide guidance for analysts on where to initiate and how to approach a new spacecraft jitter design problem. These experience-based spacecraft jitter lessons learned and rules of thumb are provided in the hope they can be leveraged on new space system development projects to help overcome unfamiliarity with previously identified jitter technical pitfalls and challenges
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