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With a renewed focus on manned exploration, NASA is beginning to prepare for the challenges that lie ahead. Future manned missions will require a symbiosis of human and robotic infrastructure. As a step towards understanding the roles of humans and robots in future planetary exploration, NASA headquarters funded ILC Dover and the University of Maryland to perform research in the area of human and robotic interfaces. The research focused on development and testing of communication components, robotic command and control interfaces, electronic displays, EVA navigation software and hardware, and EVA lighting. The funded research was a 12-month effort culminating in a field test with NASA personnel.

Introduction: There are contradictory opinions regarding the contribution of local hand thermal insulation to support local and total comfort during extravehicular activity (EVA). Instead of a local correction by means of thermal insulation on the periphery of the body to prevent heat dissipation, it may be optimal to prevent heat dissipation from the body core. To examine such a concept, the effects of different insulation levels on the left and right hands on the heat flux and temperature mosaic on the hands was measured. These variables were assessed in relation to the level of heat deficit forming in the core organs and tissues. Methods: Six subjects (4 males, 2 females) were donned in a liquid cooling/warming garment (LCWG) that totally covered the body surface except for the face. Participants wore the Phase VI space gloves including the entire micrometeoroid garment (TMG) on the left hand, and the glove without the TMG on the right hand.

As Extra-Vehicular Activity (EVA) is becoming more challenging and a renewed interest into planetary exploration is being pursued, having a spacesuit glove that is able to perform more complex and dexterous tasks with less hand fatigue is critical. In an effort to build upon an already proven foundation a new investigation has been made into reducing the torque of the Phase VI Glove Thermal Micrometeoroid Garment (TMG) along with improving dexterity and tactility. This paper addresses the makeup of the Phase VI Glove TMG and details the investigation into improving the current design. An investigation into alternative heating methods was also pursued.

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.

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.

With the initial construction of the International Space Station (ISS) underway, NASA has increased the number of astronauts to meet the demands of such a large construction effort. Both American astronauts and international partners will use NASA's space suit, the Space Shuttle Extravehicular Mobility Unit (EMU) to construct ISS. An increasing number of these new astronauts are females who do not adequately fit in the existing sizes of the EMU. In order to accommodate these astronauts, a smaller version of the EMU is under development. This development will examine all aspects of the EMU and design and fabricate new components to provide the astronauts with a space suit which provides adequate fit and is highly mobile.

The maximal capability of several body areas to absorb/release heat by varying the circulating water temperature in different zones of a multi-compartment liquid cooling/warming garment (LCWG) was explored. The goal was to identify the areas that are highly effective to stabilize body comfort, and to use this information for developing a more physiologically-based design of the space suit. The results showed a high capability of the upper compared to the lower body in the conductive heat exchange process. The involvement of the head in this process is still problematic, because there was not a high level of direct heat absorption/release through the cooling/warming hood in the LCWG. Exclusion of the legs but with involvement of the feet in heat exchange had no effect on comfort of the distal parts of the extremities and core body status.

This pilot study explored the effectiveness of local wrist warming as a potential countermeasure for providing finger comfort during extended duration EVA. Four subjects (3 males and 1 female) were evaluated in three different experimental conditions. Two additional body surface and wrist thermal conditions were evaluated on a smaller number of subjects. Wrist warming significantly increased finger temperature in ambient temperature. A clear positive effect to the fingers was evident when total body heat deficit was 30% of basal metabolic heat production in resting conditions. These initial findings indicate that wrist warming has considerable potential for increasing astronaut comfort during EVA while decreasing power requirements.

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.

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.