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NASA's next generation of space suit systems will place new demands on the pump used to circulate cooling water through the life support system and the crew's liquid cooling garment. Long duration missions and frequent EVA require increased durability and reliability; limited resupply mass requirements demand compatibility with recycled water, and changing system design concepts demand increased tolerance for dissolved and free gas and the ability to operate over a broader range of flow rates and discharge pressure conditions. This paper describes the development of a positive displacement prototype pump to meet these needs. A gerotor based design has been adapted to meet pump performance, gas tolerance, and durability requirements while providing a small, lightweight pump assembly. This design has been detailed and implemented using materials selected to address anticipated water quality and mission needs as a prototype unit for testing in NASA laboratories.

Hypothermia is a well documented problem for surgical patients and is historically addressed by the use of a variety of warming aids and devices applied to the patient before, during, and after surgery. Their effectiveness is limited in many surgeries by practical constraints of surgical access, and hypothermia remains a significant concern. Increasing the temperature of the operating room has been proposed as an alternative solution. However, operating room temperatures must be cool enough to limit thermal stress on the surgical team despite the heat transport barriers imposed by protective sterile garments. Space technology in the form of the liquid cooling garment worn by EVA astronauts answers this need. Hamilton Sundstrand Space Systems International (HSSSI) has been working with Hartford Hospital to adapt liquid cooling garment technology for use by surgical teams in order to allow them to work comfortably in warmer operating room environments.

NASA has determined that human and robotic systems will cooperate to enable the space exploration enterprise. This entails many possible forms of interaction from essentially separate sequential activities linked by data exchange (e.g. robotic precursor missions enabling subsequent human exploration) to intensely coupled simultaneous collaboration in human - robotic teams. These interactions as well as the individual robotic and human exploration system components must be shaped to make the total system robust and flexible in the face of exploration challenges that cannot be fully defined or anticipated. One powerful concept for this purpose is found in recent research on robotic “swarms”. Interacting robotic swarms have been studied in numerous research efforts as a potential means of achieving flexible and robust capabilities with comparatively simple robots.

Shuttle Extravehicular Mobility Unit (EMU) studies have shown that the thermal interaction between the crewperson, liquid cooling garment and EMU thermal management system is highly transient in nature. Recent investigations of these phenomena provide a better understanding which have helped improve thermal comfort in the present system. Analyses show that the key to thermal comfort is understanding the interaction between physiological responses and EMU system thermal transients. A test program was conducted to evaluate the theorized causes of discomfort and proposed corrective actions. Several EMU thermal management related modifications were utilized in the Hubble Space Telescope repair mission where five, two crewperson ExtraVehicular Activities (EVAs) were conducted without any thermal discomfort in a mildly cold environment.

An important, though often unstated, requirement to achieve NASA’s strategic goals will be an Extravehicular Activity (EVA) system that will let future astronauts work safely and effectively at the chosen destinations without imposing unacceptable burdens on the astronauts or the mission systems that support them. Past studies have shown that this may present an insurmountable challenge if pursued with current technologies and system design concepts. With funding from the NASA Institute for Advanced Concepts (NIAC), Hamilton Sundstrand has been studying a conceptual architecture for future EVA systems to meet this challenge. The Chameleon Suit concept shifts the EVA design paradigm from one in which the pressure garment and life support system are separate, largely independent subsystems to one in which the EVA system integrates distributed life support functions with the pressure suit.

An extremely compact heat exchanger is being developed which can boil cryogenic fluids with a liquid heat source at temperatures close to its freezing point. Freezing of the heat source fluid, e.g. water is precluded by the normal flow arrangement. Boiling and superheating of the cryogen occurs as the fluid approaches the heat source in a stack of bonded jet-array laminations. This heat exchanger technology is important in many applications where the storage of fluids at cryogenic temperatures offers substantial advantages in terms of system weight and volume. Often, as in several advanced portable life support system concepts, the advantages include the use of the cryogen as a heat sink in system thermal management. Realizing this benefit and safely conditioning the stored fluid for use requires effective heat transfer between the cryogen and a secondary heat transport fluid.

As next generation space suit concepts enable extravehicular activity (EVA) mission capability to extend beyond anything currently available today, revolutionary advances in life support technologies are required to achieve anticipated NASA mission profiles than may measure years in duration and require hundreds of sorties. Since most life support systems require power, increased mass and volume efficiency of the energy storage materials can have a dramatic impact on reducing the overall weight of next generation space suits. ITN Energy Systems, in collaboration with Hamilton Sundstrand and the NASA Johnson Space Center's EVA System's Team, is developing multifunctional fiber batteries to address these challenges. By depositing the battery on existing space suit materials, e.g. scrim fibers in the thermal micrometeoroid garment (TMG) layers, parasitic mass (inactive materials) is eliminated leading to effective energy densities ∼400 Wh/kg.

As next generation space suit concepts enable extravehicular activity (EVA) mission capability to extend beyond anything currently available today, revolutionary advances in life support technologies are required to achieve anticipated NASA mission profiles that may measure years in duration and require hundreds of sorties. Since most life support systems require power, increased mass and volume efficiency of the energy storage materials can have a dramatic impact on reducing the overall weight of next generation space suits. This paper details the development of a multifunctional fiber battery to address these needs.