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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 1,099 records · Page 61
All sourcesNASA NTRSDOE OSTI
NASA NTRS1985

Space crew productivity: A driving factor in space station design

The criteria of performance, cost, and mission success probability (program confidence) are the principal factors that program or project managers and system engineers use in selecting the optimum design approach for meeting mission objectives. A frame of reference is discussed in which the interrelationships of these pertinent parameters can be made visible, and from which rational or informed decisions can be derived regarding the potential impact of adjustments in crew productivity on total Space Station System effectiveness.

Wolbers, H. L.↗
NASA NTRS1986

Japan's participation in space station design: Feasibility study of GaAs solar cells for space station applications

The report gives the results of feasibility studies and a cost analysis done on GaAs solar battery cells for space stations. The studies and their results are as follows: (1) Cell size - The 2 x 4 cm cell size was found superior to the 4 x 4 cm cell; (2) Manufacturing technology - Overall, LPE crystal growth was found more suitable than MO-CVD. Current technology for post-growth processes and applying large-area cover glass can be used with few or no modifications; (3) Cell assemblies - Tests for mechanical and thermal stresses encountered from assembly through operation are recommended; (4) Procuring materials - Steps should be taken to avoid sharp price increases due to a speculative gallium market. There are no problems with arsenic materials; (5) Production facilities - The capital investment needed remains to be determined, but a working area of 4000 m2 will be required; (6) Cell costs to be determined; (7) Cell development-supply plan - Two-year lead time will be needed to develop the necessary technology and prepare for production.

Source record↗
NASA NTRS1986

Structural integrity and durability for Space Shuttle main engine and future reusable space propulsion systems

NASA is conducting a program which will establish a technology base for the orderly evolution of reusable space propulsion systems. As part of that program, NASA initiated a Structural Integrity and Durability effort for advanced high-pressure oxygen-hydrogen rocket engine technology. That effort focuses on the development of: (1) accurate analytical models to describe flow fields; aerothermodynamic loads; structural responses; and fatigue/fracture, from which life prediction codes can be evolved; and (2) advanced instrumentation with capabilities to verify the codes in an SSME-like environment as well as the potential for future use as diagnostic sensors for real-time condition monitoring of critical engine components.

Marsik, S. J.↗
NASA NTRS1984

Space station automation study: Automation requriements derived from space manufacturing concepts,volume 2

Automation reuirements were developed for two manufacturing concepts: (1) Gallium Arsenide Electroepitaxial Crystal Production and Wafer Manufacturing Facility, and (2) Gallium Arsenide VLSI Microelectronics Chip Processing Facility. A functional overview of the ultimate design concept incoporating the two manufacturing facilities on the space station are provided. The concepts were selected to facilitate an in-depth analysis of manufacturing automation requirements in the form of process mechanization, teleoperation and robotics, sensors, and artificial intelligence. While the cost-effectiveness of these facilities was not analyzed, both appear entirely feasible for the year 2000 timeframe.

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NASA NTRS1984

Space station automation study: Automation requirements derived from space manufacturing concepts. Volume 1: Executive summary

The electroepitaxial process and the Very Large Scale Integration (VLSI) circuits (chips) facilities were chosen because each requires a very high degree of automation, and therefore involved extensive use of teleoperators, robotics, process mechanization, and artificial intelligence. Both cover a raw materials process and a sophisticated multi-step process and are therfore highly representative of the kinds of difficult operation, maintenance, and repair challenges which can be expected for any type of space manufacturing facility. Generic areas were identified which will require significant further study. The initial design will be based on terrestrial state-of-the-art hard automation. One hundred candidate missions were evaluated on the basis of automation portential and availability of meaning ful knowldege. The design requirements and unconstrained design concepts developed for the two missions are presented.

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NASA NTRS1985

Physiologic adaptation to space - Space adaptation syndrome

The adaptive changes of the neurovestibular system to microgravity, which result in space motion sickness (SMS), are studied. A list of symptoms, which range from vomiting to drowsiness, is provided. The two patterns of symptom development, rapid and gradual, and the duration of the symptoms are described. The concept of sensory conflict and rearrangements to explain SMS is being investigated.

Vanderploeg, J. M.↗
NASA NTRS1986

Structural integrity and durability for Space Shuttle main engine and future reusable space propulsion systems

NASA is conducting a program which will establish a technology base for the orderly evolution of reusable space propulsion systems. As part of that program, NASA initiated a Structural Integrity and Durability effort for advanced high-pressure oxygen-hydrogen rocket engine technology. That effort focuses on the development of: (1) accurate analytical models to describe flow fields; aerothermodynamic loads; structural responses; and fatigue/fracture, from which life prediction codes can be evolved; and (2) advanced instrumentation with capabilities to verify the codes in an SSME-like environment as well as the potential for future use as diagnostic sensors for real-time condition monitoring of critical engine components.

Marsik, S. J.↗
NASA NTRS1986

Space Research Data Management in the National Aeronautics and Space Administration

Space related scientific research has passed through a natural evolutionary process. The task of extracting the meaningful information from the raw data is highly involved and will require data processing capabilities that do not exist today. The results are presented of a three year examination of this subject, using an earlier report as a starting point. The general conclusion is that there are areas in which NASA's data management practices can be improved and recommends specific actions. These actions will enhance NASA's ability to extract more of the potential data and to capitalize on future opportunities.

Ludwig, G. H.↗
NASA NTRS1985

Effects of space shuttle launches STS-1 through STS-9 on terrestrial vegetation of John F. Kennedy Space Center, Florida

Space Shuttle launches produce a cloud containing hydrochloric acid (HCl), aluminum oxide (Al203), and other substances. Acidities of less than 0.5 pH have been measured routinely in association with the launch cloud. In an area of about 22 ha regularly exposed to the exhaust cloud during most Shuttle launches, acute vegetation damage has resulted from the first nine Shuttle launches. Changes include loss of sensitive species, loss of plant community structure, reduction in total cover, and replacement of some species by weedy invaders. Community level changes define a retrogressive sequence. One-time impacts to strand and dune vegetation occurred after launches of STS-8 and STS-9. Acute vegetation damage occurred especially to sensitive species. Within six months, however, recovery was nearly complete. Sensitivity of species to the launch cloud was partially predicted by previous laboratory studies. Far-field acidic and dry fallout from the cloud as it rises to stabilization and moves with the prevailing winds causes vegetation spotting. Damage from this deposition is minor; typically at most 1% to 5% of leaf surface area is affected. No plant mortality or community changes have occurred from far-field deposition.

Schmalzer, P. A.↗
NASA NTRS1987

Human factors in space station architecture 2. EVA access facility: A comparative analysis of 4 concepts for on-orbit space suit servicing

Four concepts for on-orbit spacesuit donning, doffing, servicing, check-out, egress and ingress are presented. These are: the Space Transportation System (STS) Type (shuttle system enlarged), the Transit Airlock (Shuttle Airlock with suit servicing removed from the pump-down chamber), the Suitport (a rear-entry suit mates to a port in the airlock wall), and the Crewlock (a small, individual, conformal airlock). Each of these four concepts is compared through a series of seven steps representing a typical Extra Vehicular Activity (EVA) mission: (1) Predonning suit preparation; (2) Portable Life Support System (PLSS) preparation; (3) Suit Donning and Final Check; (4) Egress/Ingress; (5) Mid-EVA rest period; (6) Post-EVA Securing; (7) Non-Routine Maintenance. The different characteristics of each concept are articulated through this step-by-step approach. Recommendations concerning an approach for further evaluations of airlock geometry, anthropometrics, ergonomics, and functional efficiency are made. The key recommendation is that before any particular airlock can be designed, the full range of spacesuit servicing functions must be considered, including timelines that are most supportive of EVA human productivity.

Cohen, Marc M.↗
NASA NTRS1986

National Space Transportation System telemetry distribution and processing, NASA-JFK Space Center/Cape Canaveral

Prelaunch, launch, mission, and landing distribution of RF and hardline uplink/downlink information between Space Shuttle Orbiter/cargo elements, tracking antennas, and control centers at JSC, KSC, MSFC, GSFC, ESMC/RCC, and Sunnyvale are presented as functional block diagrams. Typical mismatch problems encountered during spacecraft-to-project control center telemetry transmissions are listed along with new items for future support enhancement.

Jenkins, George↗
NASA NTRS1987

Space station integrated wall damage and penetration damage control. Task 5: Space debris measurement, mapping and characterization system

The procedures and results of a study of a conceptual system for measuring the debris environment on the space station is discussed. The study was conducted in two phases: the first consisted of experiments aimed at evaluating location of impact through panel response data collected from acoustic emission sensors; the second analyzed the available statistical description of the environment to determine the probability of the measurement system producing useful data, and analyzed the results of the previous tests to evaluate the accuracy of location and the feasibility of extracting impactor characteristics from the panel response. The conclusions were that for one panel the system would not be exposed to any event, but that the entire Logistics Module would provide a modest amount of data. The use of sensors with higher sensitivity than those used in the tests could be advantageous. The impact location could be found with sufficient accuracy from panel response data. The waveforms of the response were shown to contain information on the impact characteristics, but the data set did not span a sufficient range of the variables necessary to evaluate the feasibility of extracting the information.

Lempriere, B. M.↗
NASA NTRS1987

A two stage launch vehicle for use as an advanced space transportation system for logistics support of the space station

This report describes the preliminary design specifications for an Advanced Space Transportation System consisting of a fully reusable flyback booster, an intermediate-orbit cargo vehicle, and a shuttle-type orbiter with an enlarged cargo bay. It provides a comprehensive overview of mission profile, aerodynamics, structural design, and cost analyses. These areas are related to the overall feasibility and usefullness of the proposed system.

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NASA NTRS1987

Advanced space solar dynamic power systems beyond IOC Space Station

Three different solar dynamic power cycle systems were evaluated for application to missions projected beyond the IOC Space Station. All three systems were found to be superior to two photovoltaic systems (a planar silicon array and a GaAs concentrator array), with both lower weight and area. The alkali-metal Rankine cycle was eliminated from consideration due to low performance, and the Stirling cycle was found to be superior to the closed Brayton cycle in both weight and area. LiF salt, which establishes peak cycle temperatures for both of the considered cycles at about 1090 K, was shown to be the most suitable material for Thermal Energy Storage.

Wallin, Wayne E.↗
NASA NTRS1987

Space power system automation approaches at the George C. Marshall Space Flight Center

This paper discusses the automation approaches employed in various electrical power system breadboards at the Marshall Space Flight Center. Of particular interest is the application of knowledge-based systems to fault management and dynamic payload scheduling. A description of each major breadboard and the automation approach taken for each is given.

Weeks, D. J.↗
NASA NTRS1987

The opportunities for space biology research on the Space Station

The life sciences research facilities for the Space Station are being designed to accommodate both animal and plant specimens for long durations studies. This will enable research on how living systems adapt to microgravity, how gravity has shaped and affected life on earth, and further the understanding of basic biological phenomena. This would include multigeneration experiments on the effects of microgravity on the reproduction, development, growth, physiology, behavior, and aging of organisms. To achieve these research goals, a modular habitat system and on-board variable gravity centrifuges, capable of holding various animal, plant, cells and tissues, is proposed for the science laboratory.

Ballard, Rodney W.↗