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Damage-Free Finishing of Silicon X-Ray Optics Using Magnetic Field-Assisted Finishing

Goddard Space Flight Center, Greenbelt, Maryland Thin, segmented mirrors have been fabricated from monocrystalline silicon blocks. The material is economically viable, and is virtually free of internal stress because of its nearly perfect crystalline structure. The mirror surfaces will first be accurately figured and finished on thick silicon blocks, then sliced off at the desired thickness by wire electro-discharge machining. A finishing process has been conceived in which existing mirror-finishing processes are adapted to be capable of quickly and accurately figuring and finishing damage-free, segmented, monocrystalline silicon mirrors in a cost-efficient manner.

Posted in: Manufacturing & Prototyping, Briefs

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Smart Crucibles and Heat Pipes

Molybdenum and molybdenum alloys are the leading candidates for making the new heat pipe modules. Marshall Space Flight Center, Alabama Near-net-shape vacuum plasma spray (VPS) forming techniques were developed to produce advanced components with internal features such as smart heat pipes and crucibles. The initial results demonstrated the ability to incorporate features such as channels and a porous layer within the wall of a smart crucible.

Posted in: Manufacturing & Prototyping, Briefs

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Technology-Independent RHBD Library Through Gate Array Approach

All gates in the library are based on one common cell. Goddard Space Flight Center, Greenbelt, Maryland As semiconductor technology nodes scale down, the limitation on polysilicon pitch makes it almost impossible to shrink libraries built for previous technologies. To design a library for a new technology, all of the cells have to basically start from scratch. Starting over for each technology node shrink is time-consuming and expensive. Further, obtaining space qualification for a technology node will require significant time and money. If a RHBD (radiation-hardened-by-design) library gates invention shares the same transistor structured as the SASIC (Structured Application-Specific Integrated Circuit), it will benefit from the existing qualification effort and high-performance advanced technology of the SASIC design flow.

Posted in: Electronics & Computers, Briefs

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Advanced Pulse Compression System and Testbed

Industrial applications include 3D machine vision systems that rely on radar for target identification and obstacle avoidance. Goddard Space Flight Center, Greenbelt, Maryland Detection of low-level water clouds from space is one of the outstanding challenges in radar remote sensing. Spaceborne remote sensing is the only means of assessing the distribution and variability of cloud cover on a global basis. Uncertainties in models of the Earth’s heating budget will persist until CloudSat and follow-on missions such as ACE (Advanced Composition Explorer), with enhanced radar capabilities, complete their missions. Detecting weak scatters at lower altitudes presents significant challenges. Millimeter-wave radars offer the only chance to measure these scatters from space. Unfortunately, the peak power available at Ka and W-band — desirable wavelengths for cloud remote sensing — does not provide adequate sensitivity at the resolution required. For many spaceborne radars, pulse compression techniques are used to overcome the limitations in peak power and take advantage of the average power available. But the backscatter from clouds, even at W-band, can be 7 to 8 orders of magnitude weaker than the surface backscatter. In order to use pulse compression techniques, peak range sidelobes need to be suppressed by upwards of 80 dB.

Posted in: Electronics & Computers, Briefs

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Quasi-Static Electric Field Generator

This generator is an essential component for human-safe electric field imaging for military and civilian security applications. Langley Research Center, Hampton, Virginia This innovation is an electric field “illumination” system that is a companion component to the e-Sensor. This generator, when combined with the e-Sensor, enables a new, nondestructive inspection technology called electric field imaging (EFI) by producing spatially uniform, large-magnitude, quasi-static electric fields with human-safe currents (supporting only microampere currents) over large areas or large distances. These fields “illuminate” the objects to be inspected, and enable the EFI method to quantify the distortion of the applied electric field of the invention to detect, locate, and characterize materials present (liquid, solid, insulating, semiconducting, conducting, metallic, non-metallic, polymer, ceramic, composite, etc.), material variations, material damage, material age, and to identify hidden structures.

Posted in: Electronics & Computers, Briefs

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Hydraulic High-Pressure Valve Controller Using the In Situ Pressure Difference

This technology is applicable to any system or device requiring high-pressure-differential valves. NASA’s Jet Propulsion Laboratory, Pasadena, California Various applications exist where high-pressure valves are required, but the problem for control of such valves lies in that they have to move against a strong pressure differential that may require significant force, energy, and large actuators. The solution to this problem is to take advantage of the in situ pressure differential to operate valves by opening small valves to change the pressure on either chamber of a hydraulic cylinder that is connected to the valve’s moving element.

Posted in: Mechanical Components, Briefs

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Safely Testing Parachute-Based Extraction Systems

Functional testing can be conducted under a wide range of performance parameters. Lyndon B. Johnson Space Center, Houston, Texas This invention relates to the safe, reliable, and repeatable testing under external load of the Extraction Force Transfer Coupling (EFTC) currently used in the extraction of airdrop platforms from both the C-17 and C-130 cargo transport aircraft. The invention enables functional testing of the EFTC at various loading angles and load magnitudes, as well as in different hardware configurations, to verify its performance in both nominal and off-nominal extraction scenarios.

Posted in: Mechanical Components, Briefs

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