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Joining advanced composite materials is one of the greatest obstacles to proliferating their use in aerospace structures. Another hindrance is the high cost of manufacturing advanced composite structures using conventional methods. The present trend in both the automotive and aerospace industries is lighter weight, energy efficient structures. In the aerospace community, the use of advanced composite structures has the potential for weight reductions of 35 to 40 percent as compared with the use of conventional aluminum alloys. However, this advantage is offset by the higher cost of manufacturing in using conventional composite technology. This paper identifies pultrusion and induction bonding as potential methods for manufacturing lightweight high-strength advanced composite structures.

Recovery of oxygen (O2) from water will be needed on future long-duration manned space missions. Direct electrolysis of cabin water vapor into O2 and hydrogen (H2) offers the advantage of avoiding the phase change, separation and handling of liquid water in zero gravity. These considerations affect liquid electrolysis subsystems which are presently baselined for central O2 generation aboard the Space Station. This paper presents the results of a technology development program that Life Systems, Inc., in cooperation with the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) has been undertaking. The goal of the program is to develop Water Vapor Electrolysis (WVE) hardware that can selectively be used as localized topping capability in areas of high metabolic activity without oversizing the central Air Revitalization System (ARS).

The direct electrochemical reduction of carbon dioxide (CO2) is achieved without catalysts and at sufficiently high temperatures to avoid carbon formation. The tubular electrolysis cell consists of thin layers of anode, electrolyte, cathode and cell interconnection. The electrolyte is made from yttria-stabilized zirconia which is an oxygen ion conductor at elevated temperatures. Anode and cell interconnection materials are complex oxides and are electronic conductors. The cathode material is a composite metal-ceramic structure. Cell performance characteristics have been determined using varying feed gas compositions and degrees of electrochemical decomposition. Cell test data are used to project the performance of a three-person CO2-electrolysis breadboard system.

This paper presents the design and the test results of a regenerative carbon dioxide control system, using solid ion exchange materials. The system applies a two bed approach with regeneration by steam and is designed far a 3 man operation. Two adsorber materials were investigated and applied throughout the tests. The system contains an evaporator, two adsorber beds, a condensing heat exchanger and an electronic controller. Test results concern the major performance parameters like CO2-loading, pressure loss, moisture range, stability ranges and energy required for dessorption. Furthermore, material dedicated analysis has been performed regarding offgassing products during operation.

The scenarios of Environmental Control and Life Support Systems (ECLSS) which will be necessary within the next sixty years are outlined. From this the need for technologies are derived and condensed in a programme plan. Technologies necessary for the Columbus Initial Operating Configuration (IOC) are already under development. The status of this programme which includes the development of regenerative CO2-control, condensing heat exchanger, contamination control and monitoring and a low noise variable speed fan is described. The areas where the technological development should start immediately are discussed.

An onboard simultaneous measuring method of solar absorptance αS and total hemispherical emittance εH for thermal control materials is proposed. This method allows to determine αS and εH simultaneously by giving different levels of input power to a sheet heater attached to the sample, and there is no need to use the values of the mass or the specific heat of the sample materials for the data reduction. In order to verify this method on the ground, the parameters αS and εH are measured for three kinds of thermal control materials.

This paper provides a description of the current European Space Suit System (ESSS) status. The ESSS is foreseen for servicing of various elements of space infrastructure within typical operational scenarios based on Hermes. As a result of different EVA studies the ESSS concept has been defined and structured in three modules: the EVA Suit Enclosure Module (ESEM), the EVA Life Support Module (ELSM), and the EVA Information and Communication Module (EICM). The main portion of the description herein is provided for the ELSM, since this module has been studied in more detail up to now (ESA contract) in comparison with the ESEM and the EICM.

There currently exist three practical processes for reduction of carbon dioxide in manned spacecraft environmental control and life support systems. The Sabatier (SCRS) and the Bosch (BCRS) Carbon Dioxide Reduction Subsystems are well known, while the Advanced Carbon Dioxide Reduction Subsystem (ACRS) is more recently developed. In this paper, the physiochemical fundamentals, developmental history, and reactor hardware implementation of these three processes are described. The methodology, data, and results of a logistics trade study of these carbon dioxide reduction processes for manned space mission application are presented and discussed.

It is necessary to remove carbon dioxide (CO2) and other contaminant gases generated from the crew and nonmetallic materials to keep the allowable level of them for the long duration life support in the space station. Therefore, the Air Revitalization System (ARS) shall be provided in the space station. The ARS for Japanese Experiment Module (JEM) consists of a regenerative CO2 removal system and a trace contaminant control system (TCCS). A solid amine CO2 removal system has been evaluated as the preferable technology. An adsorption and catalytic oxidizing method has been selected for the TCCS. This paper describes the outline of the investigations and study results of the ARS for JEM implemented on the phase B preliminary study (entrusted by NASDA) and subsequent activity.

FLUIDNET is a new computer program for preliminary sizing of fluid loop networks used in space thermal control systems. The program was developed at AEROSPATIALE'S Cannes facility, under a contract of the french space agency (CNES), on joint CNES/AEROSPATIALE funding. FLUIDNET is an interactive application, whose main features are portability, easy implementation, speed and flexibility. It is fully complementary with design tools like SINDA and ESATAN fluid loop analysis extensions (FLUINT and FHTS). The current version is applied to thermal and hydraulic analysis of single phase fluid loops in steady state. Further version is already in development with increased performances, in particular analysis of transient phases. For first applications, this program is essentially devoted to HERMES thermal control subsystem design.

This paper discusses designs for outfitting NASA Space Station Resource Nodes. It briefly summarizes the evolution of Resource Nodes to their current configuration and discusses functional and design requirements driving their overall configuration and internal outfitting. Significant features of Resource Node internal architecture, distributed system packaging, crew accommodations, and utility distribution are described. This approach to Resource Node outfitting meets current requirements for crew operations, on-orbit maintainability, and growth for the projected 30 year life of the Space Station.

This paper describes the development of a microcomputer based control system for a heat pump containing an electrical variable speed compressor drive and a motorized expansion valve. It is designed to operate under very much varying load conditions with minimum power consumption. Difficulties that were encountered during engineering tests could finally be overcome by a relatively simple, practical regulator configuration. It operates near optimum efficiency by regulating a certain temperature difference in the evaporator. Experimental data on operating characteristics and performance are included in the paper.

A baseline design has been selected for the Space Station Habitat (HAB) element. The HAB provides the primary living space to support man's permanent presence in space. The HAB element is designed to provide an environment that maximizes safety and human productivity. This paper outlines some of the current design features including the common core elements and the man-systems hardware. The HAB is arranged in three areas based on crew activity and acoustical considerations. The first area is the quiet zone, which contains the crew quarters. The second area is a buffer zone for noise suppression, where the stowage, medical facilities, and personal hygiene facilities are located. The third area is the active zone which contains the galley/wardroom, laundry and exercise facilities. Each of these three areas will be discussed together with the applicable requirements, the common utility elements, and the man-systems hardware furnishings.

Controlled ecological life support systems (CELSS) which include higher plants for food and oxygen production are proposed for permanent manned space stations and long-duration space flights. A primary concern in the design and operation of such a life support system is maintaining plant health and maximizing plant growth rates. It is inevitable that a variety of microorganisms such as fungi and bacteria will be introduced into CELSS. A potential problem for plant growth systems is plant pathogenic microorganisms. Pathogens could cause major perturbations which would be highly undesirable in a closed life support system. In CELSS plant growth systems, microorganisms can not realistically be excluded, but they can be managed to favor beneficial microorganisms and exclude undesirable microorganisms. There are 5 principal methods of managing microorganisms in plant growth systems.

Due to the late flight opportunity for the BOTANY FACILITY on the second EURECA mission a sized down facility, referred to as the MINI BOTANY FACILITY (MBF), to be flown in a re-entering capsule, for example the Russian BIOKOSMOS, is currently being studied. As a minimum, the following subsystems are baselined for the MBF: Experiment container/-cuvette, visualization, illumination, life support, thermal control, waste control and fluid supply. The paper addresses firstly the impact of the new boundary conditions (e.g. operation in pressure controlled environment, much shorter mission duration) on the selection of viable concepts for the Life Support Subsystem (LSS). Next a number of options for soil moisture control is discussed and analysed. Finally, the pre-development of components and a miniaturized sensor for soil moisture is addresssed.

In order to minimize the mass of a spaceplane, fuel cells are being used instead of batteries. For HERMES the development of a state of the art fuel cell system which can operate under micro-gravity conditions is under way. A modular simulation program SANFU (System Analyzer for FUel cells) has been developed and applied within the HERMES fuel cell project. All major parameters which influence the component or system performance are taken into account and have been simulated: temperatures, heat and mass flow, chemical reactions within the fuel cell, electrical interfaces and controller logic. The improved simulation program now includes analyses on component and/or system level, modular exchange of components such as fuel cell stack, heat exchangers, pumps, electrolyte regenerators, valves, sensors, system and component controllers, electrical and thermal bus, etc. The network topology can be changed for example in order to optimize the system configuration.

Animal research on the Space Station presents the need for bioisolation, which is here defined as instrumental and operational provisions, which will prevent the exchange of particles greater than 0.3 μ size and microorganisms between crew and animals. Current design principles for the Biological Research Project thus call for: 1. use of specific pathogen-free animals; 2. keeping animals at all times in enclosed habitats, provided with microbial filters and a waste collection system; 3. placing habitats in a holding rack, centrifuge, and workbench, all equipped with particulate and odor filters, 4. washing dirty cage units in an equipment cleaner, with treatment and recycling of the water; 5. designing components and facilities so as to ensure maximal accessibility for cleaning; 6. defining suitable operational procedures. Limited ground tests of prototype components indicate that proper bioisolation can thus be achieved.

Since the space station operates inside closed environment over long periods of time, it is essential to develop technologies to control trace contaminants produced by the metabolism of the crew and by the materials from which it is made. In order to accomplish this objective, we first of all conducted studies of both the constituents and amounts of all the trace contaminants expected to appear, and then, on the basis of these studies, we discussed the optimum means of controlling them. As a result, we selected a combination of adsorption and catalytic oxidation as the technology to control these trace contaminants. We conducted adsorption experiments, catalytic oxidation experiments, and experiments to determine the effect on the catalyst capabilities of silicon and halogen constituents, which are thought to be catalytic poisons.

CUPOLA: /'KYUP∂L∂ 1. a: a rounded vault raised on a circular or other base and forming a roof or a ceiling- compare dome: b: a small structure built on top of a roof to provide interior lighting, to serve as a lookout… During the past 24 months, the concept of a space station cupola evolved from a small, bubble-type viewport into the primary location for proximity operations requiring direct, unobstructed viewing. Derived from a viewing analysis conducted by the Man-Systems Division at the Johnson Space Center, the cupola represents a solution for out-of-plane viewing which can not be provided by windows placed in the shell of the habitation and/or laboratory modules. An extended Man-Systems design study resulted in several cupola configurations, each illustrating an alternate solution to the required balance between viewing, projected space station operations and human/machine interface issues.

In covered structures and semiclosed ecological systems on earth, disease epidemics occur frequently because pathogens can spread so rapidly. Chemical pesticides greatly reduce epidemics but alternative measures are needed for space applications. Two strategies for control are exclusion and sanitation procedures to prevent invasion of deleterious microorganisms and gnotobiotic infestation with organisms that act both as biological control agents and as plant growth promoters.