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A series of demonstration studies were conducted with the aim of better understanding how to regulate body heat and thus enhance thermal comfort of astronauts during EVA requiring intensive physical exertion. The first study evaluated body zone heat transfer under different cooling temperatures in a liquid cooling garment (LCG), confirming the effectiveness of areas with high density tissue. The second study evaluated different configurations of hoods and neck scarves to maximize heat extraction from these key areas for heat release. The third study explored the possibility of regulating body heat by control of the water temperature circulating through selected body zones in the LCG, or blocking heat dissipation from particular body areas. The potential of heat insertion/removal from the head, hands, and feet to stabilize body comfort was evaluated in terms of the ability to advance this heat current “highway” from the core.

ILC Dover Inc. was awarded a three-year NRA grant for the development of innovative spacesuit pressure garment technology that will enable safer, more reliable, and effective human exploration of the space frontier. The research focused on the development of a high performance mobility/sizing actuation system for a spacesuit soft upper torso (SUT) pressure garment. This technology has application in two areas (1) repositioning the scye bearings to improve specific joint motion i.e. hammering (Figure 1), hand over hand translation (Figure 2), etc., and (2) as a suit sizing mechanism to allow easier suit entry and more accurate suit fit with fewer torso sizes than the existing EMU. This research was divided into three phases. In phases 1 and 2 SUT actuation technologies were developed and evaluated.

Procedures for rapid microbiological analysis were performed during simulated surface extra-vehicular activity (EVA) at Meteor Crater, Arizona. The fully suited operator swabbed rock (‘unknown’ sample), spacesuit glove (contamination control) and air (negative control). Each swab sample was analyzed for lipopolysaccharide (LPS) and β-1, 3-glucan within 10 minutes by the handheld LOCAD PTS instrument, scheduled for flight to ISS on space shuttle STS-116. This simulated a rapid and preliminary ‘life detection’ test (with contamination control) that a human could perform on Mars. Eight techniques were also evaluated for their ability to clean and remove LPS and β-1, 3-glucan from five surface materials of the EVA Mobility Unit (EMU). While chemical/mechanical techniques were effective at cleaning smooth surfaces (e.g. RTV silicon), they were less so with porous fabrics (e.g. TMG gauntlet).

Introduction Human thermoregulation during EVA remains a challenge. The establishment of a high correlation between the thermal status of the fingers and the heat surplus/deficit in the body provides an index with potential to more effectively monitor and control the astronaut’s thermal status. This series of studies evaluated the changes in finger temperature (Tfing) trajectories in conditions relevant to EVA. Methods In different experiments, subjects were donned in a liquid cooling/warming garment (LCWG) that covered the full body surface except for the face and hands; they wore either a physiologically designed warming glove or the Phase VI glove. The experimental protocols were as follows: imposition of temperature differences in the left and right gloves; different thermal insulation levels of the gloves; sequential grasping of a highly cold rail in different glove conditions; placement of the finger thermistor on different sites of the finger.

ILC Dover, LP designed and manufactured a rear entry upper torso prototype for the I-Suit advanced spacesuit. In September 2005 ILC Dover participated in the Desert Research and Technology Study (RATS) led by the Advanced Extravehicular Activity (EVA) team from National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC). Desert RATS is a two-week remote field test at Meteor Crater, Arizona. Team members are from NASA, several universities, and a number of industry partners. These groups come together to gain hands-on experience with advanced spacesuit systems and to develop realistic requirements for future Moon and Mars exploration. Desert RATS gave ILC Dover the opportunity to put the rear entry I-Suit through many rigorous tests. The lessons learned there will be valuable for determining basic requirements for future lunar and Mars missions. Desert RATS utilizes a ‘learn-by-doing’ approach for understanding what future requirements should be developed.

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.

The focus of this research is on the development of a more energy efficient shortened liquid cooling/warming garment (LCWG) based on physiological principles comparing the efficacy of heat transfer of different body zones; the capability of blood to deliver heat; individual muscle and fat body composition as a basis for individual thermal profiles to customize the zonal involvement of the garment; and the development of shunts to minimize or redirect the cooling/warming loop for different environmental conditions, physical activity levels, and emergency situations. The total length of tubing in the LCWG is approximately 35% less, and the weight decreased by 45% compared to the LCVG currently used in space.

Comfort management in extreme environments is complex, requiring temperature stabilization of the body core and distal parts of the extremities. Examination of the capability of body zones to absorb and release heat can facilitate a solution to this problem. Using an experimental shortened liquid cooling/warming garment (LCWG), heat transfer effectiveness of different body zone combinations was assessed in rest and exercise conditions, at different levels of body heat deficit and intensities of physical exertion. Comfort stabilization in terms of minimum changes in core (Tc) and finger (Tfing) temperatures was achieved in exercise (200-400 W) at 18-22°C inlet water temperature in the following zonal combination: a portion of the torso, the internal thigh area covering the femoral artery, the forearm, neck, and part of the head.

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.

Experience with the Space Shuttle Extravehicular Mobility Unit (EMU) and A7LB spacesuits has shown the need to investigate new spacesuit technologies for future missions requiring highly mobile, light weight and lower cost Extravehicular Activity spacesuit alternatives. An experimental spacesuit designated the I-Suit was developed to show the feasibility of attaining all three major design goals. The I-Suit is a highly mobile, multi-bearing, all soft fabric, prototype full pressure suit designed to operate effectively in zero gravity as well as in planetary applications. The I-Suit was designed with several fixed design requirements and a long list of goals. Once the prototype suit was fabricated, laboratory environment testing was performed in order to compare the I-Suit to the Shuttle EMU spacesuit and the Apollo A7LB spacesuit.

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.

Psychological, group interaction, and task performance characteristics were evaluated in four polar expedition teams varying in national and gender composition. Leaders played a crucial role in promoting strong group cohesiveness and morale. North American members were more highly focused on achievement strivings, Russians on avoidance of failure. Gender differences in behavior were also evident. An all women's team demonstrated a high level of cooperativeness and social support of other team members. Across teams, anxiety, tension, and health concerns increased in the early stages of the expedition and decreased significantly at later stages. The overall findings indicate the need to focus on the interaction of personality, cultural, gender, and task performance demands in personnel selection and during long duration missions. Implications for the optimal design of space vehicles and habitats are discussed.

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.