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Scharfstein, Gregory

Publications and source records attributed to Scharfstein, Gregory.

3 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2012

The Mobile Chamber

A document discusses a simulation chamber that represents a shift from the thermal-vacuum chamber stereotype. This innovation, currently in development, combines the capabilities of space simulation chambers, the user-friendliness of modern-day electronics, and the modularity of plug-and-play computing. The Mobile Chamber is a customized test chamber that can be deployed with great ease, and is capable of bringing payloads at temperatures down to 20 K, in high vacuum, and with the desired metrology instruments integrated to the systems control. Flexure plans to lease Mobile Chambers, making them affordable for smaller budgets and available to a larger customer base. A key feature of this design will be an Apple iPad-like user interface that allows someone with minimal training to control the environment inside the chamber, and to simulate the required extreme environments. The feedback of thermal, pressure, and other measurements is delivered in a 3D CAD model of the chamber's payload and support hardware. This GUI will provide the user with a better understanding of the payload than any existing thermal-vacuum system.

Scharfstein, Gregory↗
NASA NTRS2011

Cryogenic Thermal Vacuum Testing with Remote Optical Metrology

Flexure Engineering was awarded an SBIR to research and develop technology needed to build a thermal vacuum chamber made to take laser radar metrology through a window. The XATF test is proof of concept for this, and demonstrated the need for such a chamber. XATF refers to two pieces of critical ground support equipment for NASA's JWST (James Webb Space Telescope) Integrated Science Instrument Module (ISIM), the ISIM Alignment Target Fixture (IATF) and the Master Alignment Target Fixture (MATF). These optical alignment assemblies require characterization while under cryogenic temperature. A thermal vacuum chamber equipped with a shroud cooled with gaseous and liquid nitrogen was used. An inner shroud was cooled with liquid helium to approximately 30K. The XATF assemblies were kinematically mounted and oriented inside the inner shroud such that the optical targets were visible from outside an optical window on one of the chamber ports. Laser radar and theodolite mounted outside the window took measurements of various optical targets. Two cold cycles were completed. A third cycle was aborted. Metrology was successfully taken. There were some problems with the helium system. The cryo pumps were turned off to reduce vibrations during metrology. Many new technologies and testing methods must be developed for JWST and future programs that will require precision measurements. These technologies will be applicable to other cold temperature applications, such as lunar missions and superconductors. Remote metrology technologies can also be applicable to testing in harsh environments. Facilities with remote metrology capability will be valuable.

Boyd, Guinevere↗