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Two-phase flow technology has the potential to significantly improve spacecraft heat acquisition, transport, and control. Using the latent heat of fluids, ammonia in particular, orders of magnitude more heat can be transferred than is possible using the sensible heat of single-phase fluids. During the past several years, two-phase heat transport systems, in which surface-tension forces established in a fine-pore capillary wick circulate the working fluid, have demonstrated performance potentials compatible with future Space Station and advanced space-based program requirements. This paper presents details of the design, analysis, fabrication, and test plan of a CPL flight experiment program. Results of this program will be important in the overall qualification of this technology for use on such advanced programs as Space Station and beyond.

The HERMES Thermal Control System necessitates the adoption of both Active and Passive Thermal Control techniques. The ATCS (Active Thermal Control Section) utilizes fluid coolant loops collecting and transporting heat loads from the various sources to the available sink devices. The methods of analysis and trade-off applied in the preliminary phase of the design activities are described, with particular attention to the selection of the fluid, the architecture of the loop, the flow sequence of the equipment in line and the redundancy policy. The design driving criteria are then discussed, outlining the optimization efforts concerning the aspects of mass saving and safety. For the PTCS (Passive Thermal Control Section), the design philosophy together with analysis approach and techniques are described.

The Space Station (SS) presents a plethora of human factors engineering opportunities. In particular, design for the space suited (extravehicular mobility unit) EVA crewperson is critical from several aspects, e.g., safety, ease of task conduct, timeline reductions, risk elimination, productivity enhancement, etc. This paper will address the human factors engineering effort undertaken to aid in the early-on design of the Space Station structure, with particular emphasis on structural assembly operations.

The HERMES Spaceplane is being designed and developed by AEROSPATIALE for the European Space Agency (ESA). The Spaceplane is designed to transport three people and three metric tons of payload to a Space Station. This paper describes the thermal control system for the HERMES Spaceplane. It is comprised of the outer thermal protection system, the internal passive thermal control system and an internal active thermal conditioning device, including and Environmental Control and life Support system (ECLS) and an Active Thermal Control System (ATCS). Different mission conditions including reentry, in-orbit and launch phases are described.

NASA-STD-3000, Man-Systems Integration Standards (MSIS), is the first NASA and industry-wide design specification for living and working in space. The EVA section of MSIS affects all future EVA systems and operations. This paper presents an overview of this far-reaching new standard with particular focus on its implications for EVA and human engineering. The MSIS provides the specific information needed to ensure proper integration of man-system interface requirements with those of other aerospace disciplines. These man-system interface requirements apply to the launch, entry, on-orbit, and extraterrestrial space environments. The MSIS is intended for use by design engineers, operations analysts, human factors specialists, and others engaged in the definition and development of manned space programs. In addition to requirements, the MSIS provides design considerations and examples for the various topics, including EVA.

Recently, interest has developed for a process to reclaim waste water from experiments in the Space Station United States Laboratory (USL). The need for a water recovery system has been generated from a growing list of experiments proposed for the Space Station that will require ultrapure water. These proposed experiments will require water that meets both USP XXI and the ASTM proposed Electronics Grade Specifications. This high quality water may be produced by a hybrid of new technologies and by water subsystems currently considered for Environmental Control and Life Support on the Space Station. To evaluate these water recovery systems and other technologies, a testing program was conducted to challenge individual water recovery subsystems with waste solutions from experiments typical of those that will be a part of the USL. The water recovery systems are being evaluated based on the permeate water quality.

A new system has been designed to simulate orbital-extravehicular (EVA) work to provide for real-time measurement of physiological parameters. Such a system described here incorporates an experimental protocol, exercising subject, controlled-atmosphere chamber, EVA-work simulation exercise device, medical instrumentation and a data acquisition system. Applications of the neutral-buoyancy method and other laboratory-simulation methods are described. This information is presented to facilitate the understanding of this exercise device as a possible additional orbital-EVA work-simulation tool. Important engineering issues associated with the design of the proposed system are discussed.

With the coming of the U.S. Space Station, the testing of the water reclamation system in zero-g could become very important to avoid costly redesigns and logistic problems. There are currently no plans to test the hardware in zero-g for long durations. This paper outlines one possible way to test the potable water reclamation system as a spacelab payload and the hygiene water reclamation system as a middeck payload in zero-g, while using existing National Space Transportation System (NSTS) flight hardware.

New components have been developed for an active thermal control system, to meet the extreme thermal requirements of the SPACELAB fluid science “Critical Point Facility”. A water cold plate with a double spiral fluid channel acts as a variable conductance heat sink for the high precision thermostat. This channel geometry achieves high heat flux densities on its planar isothermal contact surface. A thermostat unit consisting of two thermo-electrical Peltier element heat pumps and one electrical heater regulates the upstream temperature inside an air cooled electronic box. Both of these elements are pulse-width operated, to compensate the environmental temperature fluctuations.

The range of motion of space suits has traditionally been described using limited two-dimensional mapping of limb, torso, or arm movements performed in front of an orthogonal grid. This paper describes an improved technique for recovering range of motion data, and a validation of the technique performed on an Extravehicular activity space suit. The new technique uses digitized data which is automatically acquired from video images of the subject. Three-dimensional trajectories are recovered from these data, and can be displayed using three-dimensional computer graphics. Target locations are recovered using a unique video processor and close range photogrammetry. Such data can be used in a wide variety of applications, including the animation of anthropometric computer models. The applications and limitations of the new technique are discussed.

Contaminant monitoring and control is vital in maintaining a habitable atmosphere in an enclosed environment. Substances which impair normal human psychophysiological functions are constantly being produced. This requires both contaminant monitoring and removal equipment. In addition to actively removing contaminants, a passive control program can limit the types of undesirable materials allowed inside the environment. This paper will discuss potential sources of airborne contaminants, how they are monitored, and passive and active methods of contaminant control. The paper will also discuss some of the system design constraints and parameters involved in both an undersea submersible vehicle and a space based facility.

Current space lab and space shuttle workstatiins are inadeqauate for the next generation of space experimentation. The capability of the current expermient computers is severely limited, the maximum sample rate that can be acquired and processed for on board display is 10 samples per second, and the dispays have a maximum of 750 words: of storage associated with them. Second, the ability to modify experiment operations real time as non-existent unless it was programmed in approximately 18 months before glight. The appearance of new generations of computers will alleviate these problems but acceptance by the space engineering community is still limited. This paper will discuss the concepts and requirements for future workstations and capabilities that should be inherent in the next generation of space craft.

A life support system capable of sustaining crew members in an isolated, hostile environment has been designed, fabricated and tested. This system's test was funded by Air Force Systems Command through the Ballistic Missile Office and was designed to demonstrate the technology of a deep underground, remote endurance operational control facility. The three month test involved operation of the habitat under varying external environments to assess the system response. The system design supported physiological requirements such as: recycling waste water, cleansing the atmosphere of internal as well as external contaminants, and providing for emergency operations. Crew members operated the system under simulated peacetime and endurance conditions in order to assess the livability and maintainability of the facility design.

Several areas for improvement in the thermal and mechanical properties of the passive thermal control optical solar reflectors (OSRs) have been identified and discussed in a previous paper (1). These include the use of specialised optical coatings to optimise the emittance and absorptance of OSRs and also chemical treatments to provide greater resistance to handling and better conductivity where necessary. Each of the proposed techniques have been demonstrated and the most promising have been incorporated into development programmes leading to production. In parallel with this activity, examination of aspects of the whole passive thermal control system, in terms of optimal construction and assembly, and thermal and conductive properties is expected to commence shortly. It is anticipated that these will result in the specification and use of optimal thermal control systems for future satellites.

IRIS (Italian Research Interim Stage) is a European launcher which complements the NASA Space Shuttle System (STS) with an expendable, spinning solid upper stage, capable of placing payloads into orbits with energy requirements beyond the Shuttle basic capabilities. The IRIS System is completely conceived and developed in Italy by national aerospace industries led by AERITALIA. The Thermal Balance Test (TBT) activities are part of the development and qualification plan. The test has been performed on a Structural Thermal Model (STM). The purpose of this test was to qualify the thermal design and to validate the thermal mathematical models. Three relatively new circumstances characterised the testing: the actuation in a simulated space thermal environment of the Sunshield mechanism; the use of a Cargo Bay simulator; the TBT was performed at ESTEC in the new thermal vacuum chamber LSS (Large Space Simulator, which was utilized for the first time for a test of this type).

Space Biospheres Ventures, a private for-profit firm, has undertaken a major research and development project in the study of biospheres with the objective of creating and producing biospheres. Biosphere II - under construction at present and scheduled for completion in January, 1990 - will be essentially isolated from the existing biosphere by a closed structure, composed of components derived from the existing biosphere. Like the biosphere of the Earth, Biosphere II will be a stable, complex, evolving, essentially materially closed, life closed, energetically open, informationally open system containing five kingdoms of life, at least five ecosystems, plus humankind, culture and technics. Biosphere II will cover approximately 2.25 acres in floor area, and contain 5 million cubic feet in volume, with seven major biomes: tropical rainforest, tropical savannah, marsh, marine, desert, intensive agri-culture, and human habitat.

A biological treatment process employing immobilized microbial populations was field tested on contaminated ground waters and industry effluent having elevated concentrations of volatile organics, semi-volatile organics and organic pesticides, respectively. The process, consisting of a packed bed biological reactor, containing specific adapted microbial strains immobilized on a porous diatomaceous earth support was operated in a plug flow configuration over an extended period. General process measurements included temperature, pH, total organic carbon and COD. Microbial adenosine 5′-triphosphate (ATP) measurements provided estimates on immobilized biomass performance. Specific chemical analyses of waste stream constituents were determined using gas chromatography/mass spectroscopy (GC/MS) methods for both feed and treated streams.

SPACEHAB provides a habitable pressurized living compartment in the shuttle orbiter cargo bay. Previous experience in Shuttle flights demonstrated that the middeck of the crew's compartment was an excellent area for the conduct of man tended Life Science experiments. However, this same area serves both as a astronaut living area and as a working area. The availability of lockers or racks for mounting experiments or other life science hardware in the shuttle middeck is limited. SPACEHAB provides an additional 1000 cubic feet of volume, designed for ease of integration of payload, yet has a small enough load factor to facilitate manifesting opportunities. Many Life Science experiments are designed to fly in the middeck area. SPACEHAB is particularly suited to accommodate these type experiments. In addition. SPACEHAB can also accommodate space station type racks for rack mounted experiments and still retain sufficient space for such Life Science hardware as exercise machines, etc.

A field-deployable microchip gas chromatograph with high resolution capillary column separating capabilities has been linked to an external microcomputer. The instrument system produces rapid, high quality field analyses of volatile organic compounds in both ambient air and water samples with an analysis time of approximately two minutes. The newest version of the instrument system actually analyzes samples simultaneously on two capillary columns, each coated with a different liquid phase. This correlations chromatographic technique allows for a much higher degree of accuracy in compound identification than is obtainable with single capillary column analyses. A modified, temperature independent Kovats retention index system, in which the retention times of the reference compounds are calculated at ambient temperature rather than measured, eliminates the need for standard gases in the field and minimizes the need for temperature control.

After a hiatus of nearly 20 years, NASA is once again actively examining manned Mars missions. As part of this activity, a very recent engineering study has shown that providing artificial gravity for the crew of a long-duration Mars mission might be accomplished with a primary vehicle mass penalty of about 20% or less. This finding is important because it carries the promise of removing one more potential barrier to the long term human habitation of space. Before committing to the inclusion of artificial gravity on a Mars mission, however, a Variable Gravity Research Facility (VGRF) in low Earth orbit would be necessary in order to build confidence in the technology of large, flexible, rotating systems and to fill in the gaps in the scientific understanding of the response of humans to rotating, partial gravity environments. This paper discusses both the Mars mission vehicle study results and other drivers for the VGRF design.