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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.

Mechanical counter-pressure (MCP) spacesuit designs have been a promising, but elusive alternative to historical and current gas pressurized spacesuit technology since the Apollo program. One of the important potential advantages of the approach is enhanced mobility as a result of reduced bulk and joint torques, but the literature provides essentially no quantitative joint torque data or quantitative analytical support. Decisions on the value of investment in MCP technology and on the direction of technology development are hampered by this lack of information since the perceived mobility advantages are an important factor. An experimental study of a simple mechanical counter-pressure suit (elbow) hinge joint has been performed to provide some test data and analytical background on this issue to support future evaluation of the technology potential and future development efforts.

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.

Future spacesuit systems for the exploration of Mars will need to be much lighter than current designs, while at the same time reducing the consumption of water for crew cooling. One of the technology paths NASA has identified to achieve these objectives is the replacement of current high pressure oxygen storage technology in extravehicular activity (EVA) systems with cryogenic technology that can simultaneously reduce the mass of tankage required for oxygen storage and enable the use of the stored oxygen as a means of cooling the EVA astronaut. During the past year NASA has funded production of a prototype system demonstrating this capability in a design that will allow the cryogenic oxygen to be used in any attitude and gravity environment. This paper describes the design and manufacture of the prototype system. The potential significance and application of the system is also discussed.

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.

This paper is based on preliminary results of a joint study performed by MDA and Hamilton Sundstrand which examines evolving adaptive robotics systems through early robotic and human missions to the moon. NASA has placed increased emphasis on the role of robotics in future lunar exploration. The recent NASA Exploration System Architecture Study (ESAS) outlines a strategy for human return to the moon that begins with robotic precursor missions, and is followed by a series of short sortie missions made by human-robotic teams. Robotic systems would be better utilized if they can evolve to support multiple stages of the lunar exploration strategy, rather than being designed for “single-shot” mission. For example, pre-cursor rovers could be upgraded to support a human-robot sortie team, and later could remain after the astronauts depart to complete and continue exploration tasks, possibly in co-operation with other robotic assets transported on the Lunar Surface Access Module.

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.

The space exploration enterprise that will lead to human exploration on Mars requires pressure suit system capabilities and characteristics that change significantly over time and between different missions and mission phases. These capabilities must be provided within tight budget constraints and severely limited launch mass and volume, and at a pace that supports NASA's over-all exploration timeline. As a result, it has not been obvious whether the use of a single pressure suit system (like Apollo) or combinations of multiple pressure suit designs (like Shuttle) will offer the best balance among life cycle cost, risk, and performance. Because the answer to this question is pivotal for the effective development of pressure suit system technologies that will met NASA's needs, ILC and Hamilton Sundstrand engineers have collaborated in an independent study to identify and evaluate the alternatives.

NASA's plans to implement the Vision for Space Exploration include extensive human-robot cooperation across an enterprise spanning multiple missions, systems, and decades. To make this practical, strong enterprise-level interface standards (data, power, communication, interaction, autonomy, and physical) will be required early in the systems and technology development cycle. Such standards should affect both the engineer and operator roles that humans adopt in their interactions with robots. For the engineer role, standards will result in reduced development lead-times, lower cost, and greater efficiency in deploying such systems. For the operator role, standards will result in common autonomy and interaction modes that reduce operator training, minimize workload, and apply to many different robotic platforms. Reduced quantities of spare hardware could also be a benefit of standardization.

Spacesuit shoulder mobility is critical in performing EVA tasks. In addition, risk of failure must be minimized and injuries during operations and training eliminated. The pressure suit design elements that control shoulder mobility interact strongly and in complex ways with many aspects of the pressure suit and system design and are constrained by anthropometric factors. To properly develop the problem statement for the shoulder section in a new suit design that is appropriate for a return to the Moon and eventual exploration of Mars, a Quality Function Deployment (QFD) is under development. QFD is a powerful and widely used method to define your customers, determine their needs, benchmark the competition, and define engineering parameters and targets, that when met, will lead to a successful product. Since many of the requirements for the next generation suit are unknown, the QFD will continually be updated.

When humans visited the moon, the lunar rover provided an enabling resource that dramatically multiplied the scope of their exploration activities and science yield. Due to longer expected mission durations and Mars’ larger size and higher gravity, rovers will be even more crucial to effective human exploration. Unlike the Apollo program in which rovers were added part way through the program, rovers for Mars can be fully considered and integrated into the development of EVA systems at the outset. Research and mission studies of Mars exploration systems at HSSSI and elsewhere in recent years reflect this thinking. However, specifics have varied widely from small, EVA-assist rovers that are not ridden to large, pressurized rovers intended to support extended traverses over hundreds of kilometers.

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.

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 long recognized the advantages of providing improved information interfaces to EVA astronauts and has pursued this goal through a number of development programs over the past decade. None of these activities or parallel efforts in industry and academia has so far resulted in the development of an operational system to replace or augment the current extravehicular mobility unit (EMU) Display and Controls Module (DCM) display and cuff checklist. Recent advances in display, communications, and information processing technologies offer exciting new opportunities for EVA information interfaces that can better serve the needs of a variety of NASA missions. Hamilton Sundstrand Space Systems International (HSSSI) has been collaborating with Simon Fraser University and others on the NASA Haughton Mars Project and with researchers at the Massachusetts Institute of Technology (MIT), Boeing, and Symbol Technologies in investigating these possibilities.

The demands of future NASA exploration and scientific missions in space force the reevaluation of some of the basic assumptions and approaches that underlie current extravehicular activity (EVA) systems. Developing designs that can simultaneously achieve the advanced capabilities and the reductions in system mass and mission expendables targeted by NASA has proven to be a formidable challenge. The constraints of human needs, space environments, and current EVA system architectures demand technical capabilities beyond current expectations to achieve system goals. Under NASA Institute for Advanced Concepts (NIAC) sponsorship, Hamilton Sundstrand has been studying a new system paradigm to achieve the EVA system goals. The Chameleon Suit concept employs an active pressure suit that directly interacts between human systems and space environments.

Hamilton Sundstrand has been working on the development of a new cryogenic flow boiler based on its patented compact, high-intensity cooler (CHIC) technology intended to provide low weight and volume and overcome freezing problems associated with cryogen use in EVA spacesuit cooling. Tests of the prototype device resulting from that effort have now been completed. The test data demonstrate that the design is extremely resistant to freezing the heat transport fluid as anticipated. Highly effective heat transfer is achieved in a compact device combining the functions of several conventional heat exchangers. This novel heat exchanger, a “normal flow” layered impingement arrangement should provide a very compact solution to any heat transfer applications where the cold fluid operates below the warm fluid's freezing point. Test results are generally consistent with design analyses for the prototype.

In applications that require space-suited crewmembers to traverse rough terrain, boot fit and mobility are of critical importance to the crewmember's overall performance capabilities. Current extravehicular activity (EVA) boot designs were developed for micro-gravity applications, and as such, incorporate only minimal mobility features. Recently three advanced space suit boot designs were evaluated at the National Aeronautics and Space Administration Johnson Space Center (NASA/JSC). The three designs included: 1) a modified Space Shuttle suit (Extravehicular Mobility Unit or EMU) boot, 2) the Modified Experiment Boot designed and fabricated by RD & PE Zvezda JSC, and 3) a boot designed and fabricated by the David Clark Company. Descriptions of each configuration and rationale for each boot design are presented.

Hamilton Sundstrand Space Systems International (HSSSI) participated with the National Aeronautics and Space Administration (NASA), the Search for Extraterrestrial Intelligence (SETI) Institute and Simon Fraser University in the 2001 field season of NASA's Haughton-Mars Project (HMP) to study information technologies concepts and hardware systems for advanced Extravehicular Activity (EVA). The research was focused on developing an improved understanding of the uses of the interface in an exploration / field science context. Interface integration with communication, navigation and scientific data systems, and the special challenges posed by the expeditionary environment were investigated. This paper presents a discussion of the field test systems, test activities and results. Recommendations for future, higher fidelity research are included.

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.

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.