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Viewing 70801 to 70830 of 103976
1988-07-01
Technical Paper
881039
Paul A. Webley, Jefferson W. Tester
Future long term space flights will require on-board water/waste recycling in a partially or fully enclosed life support system. Oxidation of the products of human metabolism in supercritical water has been shown to be an efficient way to accomplish this recycling. Fundamental understanding of the oxidation of compounds in supercritical water is essential for the design, development and operation of a supercritical water oxidation unit. Oxidation studies of methane up to 700°C have recently been completed and are presented in this paper. Experiments are currently being performed to determine reaction kinetic parameters for the oxidation of other model compounds in supercritical water such as ammonia, methanol, acetaldehyde, and mixtures of ammonia and co-oxidants. Theoretical studies of fundamental kinetics and mechanistic pathways in supercritical water oxidation are discussed.
1988-07-01
Technical Paper
881040
Arnold O. Isenberg, Robert J. Cusick
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.
1988-07-01
Technical Paper
881050
Sjoerd L. Bonting, Roger D. Arno, Jenny S. Kishiyama, Catherine C. Johnson
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.
1988-07-01
Technical Paper
881048
Ralph Baker
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.
1988-07-01
Technical Paper
881047
Berlin Nelson
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.
1988-07-01
Technical Paper
881044
D. Parnitzki
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.
1988-07-01
Technical Paper
881056
Jen-Kuang Huang, Yong-Hua Wei, Robert L. Ash, Ming-Tsang Ho
Abstract This paper describes a prototype expert system being developed for maintaining autonomous operation of a Mars oxygen production system. System and sensor failure modes and their corresponding symptoms are identified. For a set of operating condition definitions, a knowledge-based diagnostic algorithm is developed to handle several housekeeping functions. These functions include self-health checkout; an emergency shutdown program; failure detection and isolation and active control commands. Finally, a computer simulation using BASIC language has demonstrated the feasibility of the expert system and verifies its rule-based diagnosis and decision making algorithms.
1988-07-01
Technical Paper
881054
Benton-C. Clark
Astronaut missions to Mars call for voyages remote from Earth on unprecedented scales of time and distance. Mission success will center around the management of certain critical compounds containing the atoms H and O. This generalization is true for both the life support systems and propulsion systems (for early missions at least). Mission lengths of one to three years allow virtually no possibility of timely rescue. Nonetheless, even with one or more major system failures, contingency mode H/O utilization can provide the key to survival on the road back to Earth.
1988-07-01
Technical Paper
881053
Ferolyn T. Powell
Key design drivers of the Life Support System (LSS) of advanced manned space missions are duration, distance from Earth and cost. All drive the LSS design towards the elimination of expendables and resupply requirements (from Earth). Two approaches can be taken towards achieving this goal: (1) increasing the LSS closure - via the use of regenerative technologies and (2) utilization of local resources - via the use of LSS specific technologies and/or the use of products and by-products from other systems and activities (e.g., propulsion system and manufacturing processes). Local resource utilization will be required to completely eliminate resupply requirements from Earth (e.g., to make up atmospheric losses as a result of leakage, airlock uses, etc.). Also, in some instances, it may be advantageous to utilize local resources instead of regenerative technologies. This paper provides an introduction and overview to local resource utilization related to the LSS of advanced missions.
1988-07-01
Technical Paper
881051
M. Novara, H. S. Cullingford
The piloted Mars sprint scenario of NASA's “Humans to Mars” initiative involves round-trip “sprints” with a 2-week exploration of the Martian surface. This paper investigates the bio-isolation dynamics of plants and humans in a piloted Mars sprint. To simulate a life support system for a crew of six, a transient, thermal-network model is used. Two crops, lettuce and winged beans, are chosen for a cabin greenhouse. The crew cabin and the greenhouse are physically separated but dynamically interfaced with mass and energy flows. The plants provide the bio-regenerative portion of air, water, food, and waste cycles. The percentage of contribution by bio-regeneration to air revitalization, water reclamation, wet food supply, and waste processing functions are 9, 29, 22, and 50 percent, respectively.
1988-07-01
Technical Paper
881059
H. S. Cullingford, M. Novara
This paper presents the conceptual design of a life support system sustaining a crew of six in a piloted Mars sprint. The requirements and constraints of the system are discussed along with its baseline performance parameters. An integrated operation is achieved with air, water, and waste processing and supplemental food production. The design philosophy includes maximized reliability considerations, regenerative operations, reduced expendables, and fresh harvest capability. The life support system performance will be described with characteristics of the associated physical-chemical subsystems and a greenhouse. MANNED MISSIONS TO THE PLANET MARS are included in the present NASA plans for the first decade of the next century [1]*. The first step of human exploration and eventual settlement on Mars will probably be a series of fast missions (“sprints”), with a duration of just over one year, round trip [2].
1988-07-01
Technical Paper
881061
M. C. Lee, Martin Sudar, P. S. Beckstrom, R. J. Cusick
Regenerable carbon dioxide (CO2) and moisture removal techniques that reduce expendables and logistics requirements are needed to sustain people undertaking extravehicular activities for the Space Station. Life Systems, working with National Aeronautics and Space Administration has been developing and investigating the ways to advance the Electrochemically Regenerable CO2 and Moisture Absorption (ERCA) technology to replace the nonregenerable solid lithium hydroxide absorber for the advanced Portable Life Support System (PLSS). During extravehicular activities the ERCA technique uses a mechanism involving gas diffusion and absorption into liquid absorbent for the removal and storage of the metabolically produced CO2 and moisture. Following the extravehicular activities, the expended absorbent is regenerated on-board the Space Station by an electrochemical method which restores the CO2 and moisture absorption capabilities of the absorbent.
1988-07-01
Technical Paper
881058
Warren D. Hypes, John B. Hall
A baseline ECLS system for a lunar base manned intermittently by four crewpersons and later permanently occupied by eight crewpersons has been designed. A summary of physical characteristics for the intermittently manned ECLS system includes a launch weight of 10,590 lb, launch volume of 955 ft3, 90-day resupply weight of 5972 lb, 90-day resupply volume of 346 ft3, and a power requirement of 10.494 kW. Evolution into a continuously manned base generates the following incremental requirements: launch weight of 19,935 lb, launch volume of 1178 ft3, 90-day resupply of 4928 lb, 90-day resupply of 403 ft3, and power requirement of 10.695 kW. A supplementary study assessed tankage requirements, penalties incurred by adding subsystem redundancy and by pressurizing large surface structures, and difficulties imposed by intermittent occupancy. Alternate concepts using lunar derived oxygen, the gravity field as a design aid, and a city utility type ECLS system offer potential advantages.
1988-07-01
Technical Paper
881057
S.H. Schwartzkopf, D.G. Kane, R.L. Stempson
This paper describes the major lunar resources that would be tapped in developing a Controlled Ecological Life Support System (CELSS) greenhouse for a manned lunar base. The use of the moon's gravitational field, natural sunlight, and mineral resources from the lunar surface are discussed. Lunar soil processing technologies with CELSS relevance, and their contributions to greenhouse development are presented.
1988-07-01
Technical Paper
881078
W. L. Bell, A. Miedaner, J. C. Smart, D. L. DuBois, C. E. Verostko
Long duration activities by man in space requires a regenerable CO2 removal system. Current systems under study include those based on the oxygen/hydrogen fuel cell and an amine resin. Both approaches are based on well-known acid-base chemistry of CO2. Our efforts are directed at the development of electroactive CO2 carrier molecules that are capable of binding CO2 when in the reduced form and releasing CO2 in the oxidized form. The successful development of these carriers would provide the chemical basis for a more efficient CO2 removal system and offers other potential advantages as well. The general requirements and advantages of electroactive CO2 carrier molecules are discussed. In addition, studies on carrier molecules which demonstrate the feasibility of this approach are described.
1988-07-01
Technical Paper
881077
Steven J. Carnevale, Anwyl McDonald
Conventional oxygen separation from gases has a low extraction efficiency and requires a large energy source. An innovative low power, efficient oxygen extractor could capture free oxygen from the Martian atmosphere for use in life support systems. It might also be used during the lunar oxygen separation process from the soil or a Space Station ECLSS (Environmental Control and Life Support System) for oxygen concentration and distribution. Aquanautics Corporation received a Small Business Innovative Research (SBIR) Grant from NASA's Johnson Space center to develop such a system. The contract began in January 1988. The technology has involved a substantial research effort that is now entering into the first phase of prototype development. This paper discusses the technology in general terms and the specific work which is being performed for NASA to determine the feasibility for Martian applications.
1988-07-01
Technical Paper
881075
G. Primeaux, K. Newkirk, L. Miller, G. Lewis, R. Michaud, M. Singletary, N. Wilson, D. Herrin, N. Jackson
Life sciences research facilities planned for the U.S. Space Station will accommodate life sciences investigations addressing the influence of microgravity on living organisms. Current projects within the Life Sciences Space Station Program (LSSSP), the Life Sciences Space Biology (LSSB) and Extended Duration Crew Operations (EDCO) projects, will explore the physiological, clinical, and sociological implications of long duration space flight on humans and the influence of microgravity on other biological organisms/systems. Initially, the primary research will emphasize certifying man for routine 180-day stays on the Space Station. Operational crew rotations of 180 days or more will help reduce Space Station operational costs and minimize the number of Space Transportation System (STS) shuttle flights required to support Space Station.
1988-07-01
Technical Paper
881073
Paul C. Rambaut
The advent of non-resupplied space missions of several year's duration poses some unique nutritional problems. Such problems have been of little consequence on missions that have been resupplied with natural foods at intervals of from one to two months or on missions that have been so short that the body's reserves of essential nutrients have not been depleted. Foods used on prolonged, non-resupplied missions must, in addition to providing a nutrient supply sufficient to meet ground-based nutritional requirements, also provide nutrients at levels needed to minimize any adverse effects stemming from weightlessness. Nutritional specifications must also reflect the now well recognized relationships between nutrition and such diseases as cancer and atherosclerosis.
1988-07-01
Technical Paper
881094
James A. Strack
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.
1988-07-01
Technical Paper
881095
Scott R. Johnson
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.
1988-07-01
Technical Paper
881096
William F. Dempster
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.
1988-07-01
Technical Paper
881112
K. Otsuji, O. Hanabusa, T. Etoh, M. Minemoto
One of the most closely related system to the life of crew in a manned spacecraft is the Environment Control and Life Support System. ECLSS includes such functions as temperature control, humidity control, pressure control, air circulation, carbon dioxide removal and concentration, carbon dioxide reduction and oxygen generation, and contamination control. The first Japanese space habitable system called JEM (Japanese Experimental Module) will be operated by being attached to the U.S. Space Station. Several functions such as CO2 and trace contaminant control are considered in JEM. while others are dependent on the U.S. module. (1)* It is necessary to expand ECLS functions for the future Japanese peculiar space station. Solid Amine water desorbed carbon dioxide removal and concetration test bed using heat recovery provision for the energy saving operation has been successfully tested with more than 99% of carbon dioxide concentration purity.
1988-07-01
Technical Paper
881079
R. M. Taylor, E. S. Van Valkenburg, R. J. Cusick
A new type of oxygen sensor is being developed for potential use in future manned space missions. This sensor incorporates two independent measurement schemes using dual electrochemical cells formed in a common body of solid electrolyte-zirconia. A combination of potentio-metric and coulometric measurements yields accurate and fast response to cabin atmosphere oxygen. Means for self-calibration, fault detection and diagnosis by computer operation are discussed.
1988-07-01
Technical Paper
881080
John W. Small, Wayne L. Odegard
This paper discusses new technology developments in carbon dioxide (CO2) detection using Non-Dispersive Infrared (NDIR) techniques. The method described has successfully been used in various applications and environments. It has exhibited extremely reliable long-term stability without the need of routine calibration. The analysis employs a dual wavelength, differential detection approach with compensating circuitry for component aging and dirt accumulation on optical surfaces. The instrument fails “safe” and provides the operator with a “fault” alarm in the event of a system failure. The NDIR analyzer described has been adapted to NASA Space Station requirements and a breadboard furnished under NASA contract NAS9-17612.
1988-07-01
Technical Paper
881081
Robert S. Barker, Kenneth T. So
The G198A generalized environmental control and life support system (ECLSS) simulation computer program has a library of ECLSS component and subsystem subroutines that can be used to model the complexity of planned ECLSS's for advanced manned spacecraft. The G189A program has successfully provided the necessary mathematical modeling functions for the Skylab and the Space Shuttle orbiter. This paper presents developments at Rockwell International concerning the preparation of the user-friendly computer program (PrepG189) for facilitating G189A program schematics and input data preparation. The two major subprograms in PrepG189 are the schematic processor and the panel processor. The program is operated on a VAX computer terminal. A high level of maneuverability has been achieved in moving between the subordinate portions of the program that participate in numerical data and schematic preparation.
1988-07-01
Technical Paper
881082
H. V. Venkatasetty
There is a great need for reliable environmental sensors that can monitor the concentrations of gases and vapors such as oxygen, carbon dioxide, carbon monoxide, water vapor and other contaminants of the cabin air in a manned space station. Honeywell has developed a new class of electrochemical gas sensors based on nonaqueous electrolytes. Sensors with three electrode configuration and gold sensing electrodes have been fabricated and used for monitoring both carbon dioxide and oxygen with the capability to monitor water vapor using linear scanning voltammetry. Sensors with platinum sensing electrodes have been used to monitor low concentrations of toxic gases such as carbon monoxide and nitrogen oxides with potential capability to monitor organic contaminants. Experimental results obtained with these low-power and microprocessor-based sensors will be presented.
1988-07-01
Technical Paper
881119
Richard L. Olson, Brand N. Griffin, James S. Hawkins
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.
1988-07-01
Technical Paper
881118
Dr. Helmut R. Löser
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.
1988-07-01
Technical Paper
881121
Daryl Rasmussen, Vicki Johnson, Arshad Mian
Abstract The operational environment for life sciences on the Space Station will incorporate telescience, a new set of operational modes for conducting science and operations remotely. This paperpresents payload functional requirements for Space Station Life Sciences habitat monitoring and control and describes telescience concepts and technologies which meet these requirements. Special considerations for designing sensors and effectors to accommodate future evolutions in technology are discussed.
1988-07-01
Technical Paper
881120
John F. Daily, Frank T. Eichstadt, John B. Lauger
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.