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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Gravity-sag (G-sag) for large space-based telescopes is a critical error budget element that must be taken in consideration. Absolute characterization of gravity sag provides necessary information when testing light weighted optics so that true optical performance can be determined. A method is presented for characterizing G-sag to obtain the 0-G optical surface.
The recent accelerated growth in space-related research and development activities makes the near-term need for long-term extraterrestrial habitats evident. Such habitats must operate under continuous disruptive conditions arising from extreme environments like meteoroid impacts, extreme temperature fluctuations, galactic cosmic rays, destructive dust, and seismic events. Loss of air or atmospheric leakage from a habitat poses safety challenges that demand proper attention. Such leakage may arise from micro-meteoroid impacts, crack growth, bolt/rivet loosening, and seal deterioration. In this paper, leakage estimation in deep space habitats is posed as an inverse problem. A forward pressure-based dynamical model is formulated for atmospheric leakage. Experiments are performed on a small-scaled pressure chamber where different leakage scenarios are emulated and corresponding pressure values are measured. An exponentially-weighted adaptively-refined search (EWARS) algorithm is developed and validated for the inverse problem of real-time leakage estimation. It is demonstrated that the proposed methodology can achieve real-time estimation and tracking of constant and variable leaks with accuracy.
Characterizing Gravity-sag (G-sag) is an essential part of developing a large space-based optic. A method to back out gravity sag of a light-weighted optic using a CGH will be demonstrated. The results from the G-sag CGH determination is compared to the G-sag and Zero-G figure obtained during horizontal G-sag testing. The results from the CGH testing are also compared to the G-sag figure determined from modeling.
Ebulliometric and end-group molecular weights of polyoxypropylene and polyoxyethylene glycols
Initial weight loss of plastics in a vacuum
Design of spacecraft shielding of minimum weight - protons and secondary neutrons
Fabrication and experimental evaluation of light- weight solar concentrators
Radiant black body heat rejection and weight characteristics of fin tube space radiators with linearly tapered fins
Effect of weight, density, and heat load on performance of heat shield of phenolic resin and nylon powder
Proceedings of eleventh general conference of weights and measures
Cross check study of vacuum compatibility of polystyrene and polymethylmethacrylate - weight loss determination
By mounting the Fresnel lens in eight steps above three paraboloidal reflector rings of epoxy resin with aluminized surfaces, a light weight, wide-aperture solar energy collector is devised.
Minimum weight proton shield synthesis for space vehicles
Computation of weighted root mean square of path length changes caused by deformations and imperfections of rotational paraboloidal antennas using digital computer program
Electrochemical study of prospective electrode- electrolyte systems for high-energy primary battery with minimum of 200 watt hours per pound of total battery weight
High performance light weight fuel cell electrode development