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For NASA's Constellation Program, an Intravehicular Activity (IVA) and Extravehicular Activity (EVA) Life Support Umbilical System (LSUS) will be required to provide environmental protection to the suited crew during Crew Exploration Vehicle (CEV) cabin contamination or depressurization and contingency EVAs. The LSUS will provide the crewmember with ventilation, cooling, power, communication, and data, and will also serve as a crew safety restraint during contingency EVAs. The LSUS will interface with the Vehicle Interface Assembly (VIA) in the CEV and the Suit Connector on the suit. This paper describes the effort performed to develop concept designs for IVA and EVA umbilicals, universal multiple connectors, handling aids and stowage systems, and VIAs that meet NASA's mission needs while adhering to the important guiding principles of simplicity, reliability, and operability.

Lunar dust exposures occurred during the Apollo missions while the crew was in the lunar module on the moon's surface and especially when micro-gravity conditions were attained during rendezvous in lunar orbit. Crews reported that the dust was irritating to the eyes, and in some cases, respiratory symptoms were elicited. NASA's current vision for lunar exploration includes stays of 6 months on the lunar surface hence the health effects of periodic exposure to lunar dust in the habitat need to be assessed. NASA is performing this assessment with a series of in vitro and in vivo tests with authentic lunar dust. Our approach is to “calibrate” the intrinsic toxicity of lunar dust by comparison to a relatively low toxicity dust (TiO2) and a highly toxic dust (quartz) using intrapharyngeal instillation of the dusts to mice. A battery of indices of toxicity is assessed at various time points after the instillations.

The Geoscience Laser Altimeter System (GLAS) instrument is NASA Goddard Space Flight Center's first application of Loop Heat Pipe technology that provides selectable/stable temperature levels for the lasers and other electronics over a widely varying mission environment. GLAS was successfully launched as the sole science instrument aboard the Ice, Clouds, and Land Elevation Satellite (ICESat) from Vandenberg AFB at 4:45pm PST on January 12, 2003. After SC commissioning, the LHPs started easily and have provided selectable and stable temperatures for the lasers and other electronics. This paper discusses the thermal development background and testing, along with details of early flight thermal performance data.

A sorption-spectrophotometric platform for the concentration and subsequent quantification of biocides in spacecraft drinking water is described. This methodology, termed Colorimetric Solid Phase Extraction (C-SPE), is based on the extraction of analytes onto a membrane impregnated with a colorimetric reagent. Quantification of the extracted analytes is accomplished by interrogating the surface of the membrane with a commercially available diffuse reflectance spectrophotometer. Ground-based experiments have shown that C-SPE is a viable means to determine biocide concentrations in the range commonly found in water samples from the Space Shuttle and the International Space Station (ISS). This paper details efforts to advance C-SPE closer to space flight qualification and ISS implementation, starting with the modification of the ground based biocide detection platform to simplify operation in a microgravity environment.

The primary objectives of this study were to determine the factors that affect stability during locomotion in both lunar and martian gravity environments and to determine the criteria needed to enhance stability and traction. This study tested the effects of changing the speed of locomotion and the pattern of locomotion under three gravity conditions. The results showed that as the gravity level decreased, the amount of vertical and horizontal forces dropped significantly. The results also showed that there are some similarities across gravity levels with regard to changing the speed as well as the pattern of locomotion. In general, an increase in the speed resulted in an increase in the vertical and the horizontal forces. A change in the pattern of locomotion showed that even at reduced gravity, it will be more difficult to stop than compared to continue or start the motion.

The Hubble Space Telescope (HST) was designed to be serviced from the shuttle by astronauts performing extravehicular activities (EVA). During the first HST Servicing Mission (STS-61) two types of power tools were flown, the Power Ratchet Tool (PRT) and the HST Power Tool. Each tool had both benefits and drawbacks. An objective for the second HST servicing mission was to combine the reliability, accuracy, and programmability of the PRT with the pistol grip ergonomics and compactness of the HST Power Tool into a new tool called the EVA Pistol Grip Tool (PGT). The PGT is a self-contained, microprocessor controlled, battery powered, 3/8-inch drive hand-held tool. The PGT may also be used as a non-powered ratchet wrench. Numerous torque, speed, and turn or angle limits can be programmed into the PGT for use during various servicing missions. Batteries Modules are replaceable during ground, Intravehicular Activities (IVA), and EVA operations.

This paper describes flight test results of the CAPL 2 Flight Experiment, which is a full scale prototype of a capillary pumped loop (CPL) heat transport system to be used for thermal control of the Earth Observing System (EOS-AM) instruments. One unique feature of CAPL 2 is its capillary starter pump cold plate design, which consists of a single capillary starter pump and two heat pipes. The starter pump enhances start-up success due to its self-priming capability, and provides the necessary capillary pumping force for the entire loop. The heat pipes provide the required isothermalization of the cold plate. Flight tests included those pertinent to specific EOS applications and those intended for verifying generic CPL operating characteristics and performance limits. Experimental results confirmed that the starter pump was indeed self-priming and the loop could be successfully started every time.

The Capillary Pumped Loop Flight Experiment (CAPL 2) employs a passive two-phase thermal control system that uses the latent heat of vaporization of ammonia to transfer heat over long distances. CAPL was designed as a prototype of the Earth Observing System (EOS) instrument thermal control systems. The purpose of the mission was to provide validation of the system performance in microgravity, prior to implementation on EOS. CAPL 1 was flown on STS-60 in February, 1994, with some unexpected results related to gravitational effects on two-phase systems. Start-up difficulties on CAPL 1 led to a redesign of the experiment (CAPL 2) and a reflight on STS-69 in September of 1995. The CAPL 2 flight was extremely successful and the new “starter pump” design is now baselined for the EOS application. This paper emphasizes the design history, the CAPL 2 design, and lessons learned from the CAPL program.

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.

As the maintenance and disposal costs of aircraft batteries have risen, it has become critical to increase battery lifetime and to reduce maintenance cycles. This has led to the development of charging techniques designed to increase battery life while continuing to satisfy battery performance requirements. However, the cost of battery chargers accounts for 60% to 80% of the battery/charger system cost. AFRL/PRPB has initiated an in-house project to evaluate F-16 batteries using the existing F-16 charger. The objective is to determine which batteries can pass all F-16 performance and lifetime requirements using this charger. Several batteries were procured from several sources and two F-16 chargers are on loan to us from Sacramento/ALC. Depending on the outcome of this phase the project may be extended to include other aircraft and other chemistries such as Nickel-Metal Hydride and Lithium-Ion. Results to date and future plans will be discussed in this paper.

The thermal design and modeling of NASA’s James Webb Space Telescope (JWST) Integrated Science Instrument Module (ISIM) is described. The ISIM utilizes a series of large radiators to passively cool its three near-infrared instruments to below 37 Kelvin. A single mid-infrared instrument is further cooled to below 7 Kelvin via stored solid Hydrogen (SH2). These complex cooling requirements, combined with the JWST concept of a large deployed aperture optical telescope, also passively cooled to below 50 Kelvin, makes JWST one of the most unique and thermally challenging space missions flown to date. Currently in the preliminary design stage and scheduled for launch in 2010, NASA’s JWST is expected to replace the Hubble Space Telescope as the premier space based astronomical observatory.