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The I-Suit has been tested in varying environments at Johnson Space Center (JSC). This includes laboratory mobility testing, KC-135 partial gravity flights, and remote field testing in the Mojave Desert. The experience gained from this testing has provided insight for design improvements. These improvements have been an evolutionary process since 1998 to the present. The design improvements affect existing suit components and introduce new components for systems processing and human/robotic interface. Examples of these design improvements include improved mobility joints, a new helmet with integrated communications and displays capability, and integration of textile switches for control of suit functions and tele-robotic operations. This paper addresses an overview of I-Suit design improvements and results of manned and unmanned performance tests.

Since the early 1980’s, the Shuttle Extra Vehicular Activity (EVA) glove design has evolved to meet the challenge of space based tasks. These tasks have typically been satellite retrieval and repair or EVA based flight experiments. With the start of the International Space Station (ISS) assembly, the number of EVA based missions is increasing far beyond what has been required in the past; this has commonly been referred to as the “Wall of EVA’s”. To meet this challenge, it was determined that the evolution of the current glove design would not meet future mission objectives. Instead, a revolution in glove design was needed to create a high performance tool that would effectively increase crewmember mission efficiency. The results of this effort have led to the design, certification and implementation of the Phase VI EVA glove into the Shuttle flight program.

The NASA/Industry Shuttle EMU team initiated an EMU program activity in 1988 to reduce EMU criticality 1 failure causes, reduce ground operations costs, and also to enhance on-orbit operational Extravehicular Activity (EVA) capability. Replacement/refurbishment hardware is being developed, certified, and delivered. System level life extention testing is expected to extend the Life Limited Components replacement schedule. Goals of this program are to achieve a 25 percent reduction in ground turn-around man-hours and processing time between missions and to extend Extravehicular Activity (EVA) on-orbit capabilities expected to be necessary to support Space Station Freedom assembly and contingency EVA operations. This paper identifies and describes tasks being implemented with expected benefits to NASA-manned spaceflight programs.

In order to provide effective cooling for astronauts during extravehicular activities (EVAs), a liquid cooling and ventilation garment (LCVG) is used to remove heat by a series of tubes through which cooling water is circulated. To better predict the effectiveness of the LCVG and determine possible modifications to improve performance, computer simulations dealing with the interaction of the cooling garment with the human body have been run using the Wissler Human Thermal Model. Simulations have been conducted to predict the heat removal rate for various liquid cooled garment configurations. The current LCVG uses 48 cooling tubes woven into a fabric with cooling water flowing through the tubes. The purpose of the current project is to decrease the overall weight of the LCVG system. In order to achieve this weight reduction, advances in the garment heat removal rates need to be obtained.

The success of astronauts performing Extra-Vehicular Activity (EVA) is highly dependent on the performance capabilities of their spacesuit gloves. Thermal protection of crewmember's hands has always been a critical concern but has recently become more important because of the increasing role of the crewmember in the manipulation of objects in the environment of space. The utilization of EVA for challenging missions, such as the Hubble Space Telescope (HST) repair and Space Station assembly missions, has prompted the need for improved glove thermal protection. The increased manipulation of hot and cold objects is necessary to complete these complex missions. Thermal protection of the spacesuit glove is accomplished by the Thermal and Micrometeoroid Garment (TMG). The TMG is a multilayered cover that fits over the restraint layer of the spacesuit glove. The TMG is engineered to provide thermal protection for crewmember's hands as well as for the glove bladder and restraint.

Recent Shuttle extravehicular activity (EVA) missions have shown the need for improved thermal performance in Space Suit Assembly (SSA) gloves to successfully complete assembly of the International Space Station (ISS). Passive thermal design improvements have been successfully incorporated, however, additional improvements are still possible. An Active Heated Glove Assembly was developed to aid in the prevention of cold hands and fingers during periods of rest and low metabolic activity. Environmental vacuum tests have shown that the system accomplishes its goals and measurably increases glove thermal performance.

The continuous development of Extravehicular Activity (EVA) spacesuit gloves has lead to an effective solution for performing EVA to date. Some aspects of the current EVA gloves have been noted to affect crew performance in the form of limited dexterity and accelerated onset of fatigue from high torque mobility joints. This in conjunction with the fact that more frequent and complex EVAs will occur with the fabrication and occupation of Space Station Freedom, suggest the need for improved spacesuit gloves. Therefore, several efforts have been conducted in the recent past to enhance the performance of the spacesuit glove. The following is a description of the work performed in these programs and their impact on the design and performance of EVA equipment. In the late 1980's and early 1990's, a spacesuit glove design was developed that focused on building a more conformal glove with improved mobility joints that could function well at a higher operating pressure.

Integration of the water and air treatment systems in confined habitats for extended duration space missions will require characterization of the constituents in the gases produced by biological water processors. A membrane bioreactor was constructed to accomplish nitrification as part of a denitrification-nitrification biological water processor to treat a simulated early planetary base wastewater. A gas chromatograph was installed inline to the influent and effluent gas lines of the membrane bioreactor to monitor nitrogen, oxygen, carbon dioxide and nitrous oxide. The inline monitoring system enabled sampling of gas effluent from the lumen of the membranes and from a gas-liquid separator. Mass flow of the gas streams was also measured to enable calculation of the mass flow rates of the four inorganic gases.

The shortened liquid cooling/warming garment (SLCWG) developed by the University of Minnesota group was compared with the standard NASA liquid cooling/ventilating garment (LCVG) garment during physical exertion in comfort (24°C) and hot (35°C) chamber environments. In both environmental conditions, the SLCWG was just as effective as the LCVG in maintaining rectal temperature (Tre) in a thermal comfort range; sweat production on the face was less; and subjective perception of overall and local body comfort was higher. The findings indicate that the SLCWG produces the same or greater comfort level as that achieved with the LCVG's total coverage of the body surface.

This paper presents an uncertainty analysis of aerodynamic force and moment coefficients for production vehicles in an automotive wind tunnel. The analysis uses a Monte Carlo numerical simulation technique. Emphasis is placed on defining the elemental random and systematic uncertainties from the tunnel’s instrumentation, understanding how they propagate through the data reduction equations and under what conditions specific elemental error sources are or are not important, and how the approach to data reduction influences the overall uncertainties in the coefficients. The results of the analysis are used to address the issue of averaging time in the context of maintaining a maximum allowable uncertainty level. Also, a maximum error requirement in the vehicle’s installation is suggested to allow the use of rapid but approximate vehicle alignment methods without incurring errors that exceed the data uncertainty. Observed reproducibility results are presented spanning a 16 month period.

ILC Dover, Inc. under contract to the United States Air Force Human Systems Division (AFSC) has developed a prototype laboratory test garment known as the “Advanced High Altitude Flight Suit” (AHAFS). The suit incorporates technologies first developed for NASA with the Apollo and Shuttle programs, but optimized in their present iteration for long term uninflated wear (as emergency decompression protection) in pressurized aircraft cockpits. The program has additionally attempted to achieve better mobility in the pressurized state by defining and systematically addressing a specified mobility envelope. Related construction techniques employ single and double axis “soft” joints, which can be engineered to permit full access to existing or contemplated cockpit designs. Proper balancing of wall tensions across these joints has resulted in lower suit loads, increased mobility, and established the feasibility of a higher suit operating pressure (5 psi).

Recent technological advancements in space inflatable structures, in the areas of material rigidization and controlled deployment, have presented a new possibility to the space community with a low cost, lightweight alternative to mechanically deployed space structures. Space inflatable structures have many benefits and advantages over current mechanical systems. They are low in mass and can be packaged into small volumes, which can potentially reduce the overall program cost by reducing the launch vehicle size. Reduction in total system mass and deployment complexity can also increase system reliability. This new technology is fast becoming a reality, especially in the field of inflatable solar arrays and other applications for spacecraft components.

Future spacesuits will require thermal insulation protection in low-earth orbit (LEO), in the near-earth neighborhood and in planetary environments. In order to satisfy all future exploration needs and lower production and maintenance costs, a common thermal insulation is desirable that will perform well in all these environments. A highly promising material is a fiber-reinforced aerogel composite insulation currently being developed at the Johnson Space Center. This paper presents an overview of aerogels and their manufacture, a summary of the development of a flexible fiber-based aerogel for NASA by Aspen Aerogels, Inc., and performance data of aerogels relative to flexible commercial insulation. Finally, future plans are presented of how an aerogel-based insulation may be integrated into a spacesuit for ground testing as well as for a flight configuration.