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Foster-Miller, Inc., is currently developing a heat pump system to produce hot water for crew hygiene on future manned space missions. The heat pump utilizes waste heat sources and a nonazeotropic working fluid in a highly efficient cycle. The potential benefits include a reduction in peak power draw from 2 to 5 kW for electric cartridge heaters, to just over 100W for the heat pump. As part of the heat pump development program, a unique high efficiency compressor was developed to maintain lubrication in a zero-gravity environment. Initial testing has resulted in measured COPs of 8.5.

This paper discusses the development of driver-vehicle interface (DVI) requirements for an inner-city transit bus collision avoidance system (CAS). In 1998, there were over 23,000 transit bus collisions resulting in over 20,000 injuries. Using structured interviews with transit bus operators and naturalistic observation, the transit bus operating environment was characterized. Then, a set of CAS functional requirements was generated. Lastly, a set of human factors DVI requirements for a transit bus CAS was developed. The DVI requirements focused on the physical aspects of the display and the display's cognitive demands on the bus operator.

This paper describes the process and analysis used to select a refrigerant and thermodynamic cycle as the basis of a vapor compression heat pump requiring a high temperature lift. Use of a vapor compression heat pump versus other types was based on prior work performed for the Electric Power Research Institute. A high lift heat pump is needed to enable a thermal control system to remove heat down to 275K from a habitable volume when the external thermal environment is severe. For example, a long term habitat will reject heat from a space radiator to a 325K environment. The first step in the selection process was to perform an optimization trade study, quantifying the effect of radiator operating temperature and heat pump efficiency on total system mass; then, select the radiator operating temperature corresponding to the lowest system mass. Total system mass included radiators, all heat pump components and the power supply system.

The Locally Commutated Linear Synchronous Motor (LCLSM) concept was analyzed and demonstrated. Design and analysis of an 8 MW propulsion motor for a Maglev vehicle resulted in an LCLSM system capable of generating smooth thrust with non-overlapping propulsion coils. Each coil is separately powered by a dedicated H-bridge inverter operating from a DC bus and controlled by a dedicated microcontroller which communicates to a base station via fiber optic bus. A 1/10th scale experiment was built which demonstrated the viability of the LCLSM concept. Very high efficiency, power factor, reliability, system flexibility, ride quality and levels of safety can be achieved with LCLSM.