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The thermal design strategy is discussed as it relates to the production of up to 34 identical small satellites in a relatively short period of time. Tight production and launch schedules and the need to design for low mass, risk, and cost presented a design challenge for all disciplines. A specific arrangement of passive thermal control features, including ITO-coated AgTef covered structure radiators, MLI, and software controlled heaters established a robust design. Thermal modeling of the bus and unique antenna are presented including a comparison between the predicted and required component temperature ranges. Also described are the primary mission objective, the spacecraft configuration, requirements and design drivers, mission environments, and design parameters.

A wide range of environmental exposures, stringent payload interface conditions, a low risk requirement, low allowable heater power, constraints of a fixed price contract and aggressive schedule presented a challenge in developing the FUSE bus (spacecraft) thermal design. The bus provides power, attitude control and telemetry for the satellite, which includes the bus and instrument payload. The thermal design that evolved is remarkably self-regulating. This is attributed to the synergistic effect of a compact structure that allows cross-coupling of radiators with different exposures in addition to the advantages of a large louver. This paper discusses the design approach, key thermal control features, supporting analyses and trade studies, and how predicted results compare with requirements for the design envelope and beyond.

New Space Support Equipment (SSE) components developed for the Hubble Space Telescope Second Servicing Mission are described, with particular emphasis on how flight experience from the 1993 First Servicing Mission was utilized in the design and testing process. The new components include the Second Axial Carrier (SAC) Axial Scientific Instrument Protective Enclosure (ASIPE), the magnetic-damped SAC ASIPE Load Isolation System, the Enhanced Power Distribution and Switching Unit (EPDSU), and the Multi-Mission Orbital Replacement Unit Protective Enclosure (MOPE). Analytical modeling predictions are compared with on-orbit data from the Hubble Space Telescope (HST) Second Servicing Mission. Those involved in thermal designs of hardware for use on the Shuttle or Space Station, particularly with astronaut interaction, may find interest in this paper.

Chemical processing of the dusty, low-pressure Martian atmosphere for production of propellants and other consumables will require conditioning and compression of the gases as first steps. A temperature-swing adsorption process can perform these tasks using solid-state hardware and with relatively low power consumption compared to alternative processes. The process can also separate the atmospheric constituents, producing both pressurized CO2 and a buffer gas mixture of nitrogen and argon. We have developed and tested adsorption-based compressors with production levels appropriate for near-term robotic flight experiments, which are needed to demonstrate the basic technologies for ISRU-based human exploration missions. In this talk we describe the characteristics, testing, and performance of these devices. We also discuss scale-up issues associated with meeting the processing demands of sample return and human missions.

Common bus spacecraft development and constellations of spacecraft such as ORBCOMM have led to a need for common thermal models. For years, spacecraft design engineers have used common parts stored in a parts library to expedite the process of drafting the spacecraft in a CAD package such as Pro/Engineer. This methodology is implemented into the thermal modeling process for common parts used on one or more spacecraft. Using the previously developed Pro/Engineer parts library as the model template, the component thermal model is developed in FEMAP and translated into a complete thermal model using the TCON thermal software suite. The models are checked for accuracy at the component level to ensure that errors do not propagate to system level models. The result is a component level thermal model ready for integration into a system level model.