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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 235 records · Page 13
All sourcesNASA NTRSDOE OSTI
NASA NTRS1978

Estimate of procession and polar motion errors from planetary encounter station location solutions

Jet Propulsion Laboratory Deep Space Station (DSS) location solutions based on two JPL planetary ephemerides, DE 84 and DE 96, at eight planetary encounters were used to obtain weighted least squares estimates of precession and polar motion errors. The solution for precession error in right ascension yields a value of 0.3 X 10 to the minus 5 power plus or minus 0.8 X 10 to the minus 6 power deg/year. This maps to a right ascension error of 1.3 X 10 to the minus 5 power plus or minus 0.4 X 10 to the minus 5 power deg at the first Voyager 1979 Jupiter encounter if the current JPL DSS location set is used. Solutions for precession and polar motion using station locations based on DE 84 agree well with the solution using station locations referenced to DE 96. The precession solution removes the apparent drift in station longitude and spin axis distance estimates, while the encounter polar motion solutions consistently decrease the scatter in station spin axis distance estimates.

Pease, G. E.↗
NASA NTRS1980

Central station market development strategies for photovoltaics

Federal market development strategies designed to accelerate the market penetration of central station applications of photovoltaic energy system are analyzed. Since no specific goals were set for the commercialization of central station applications, strategic principles are explored which, when coupled with specific objectives for central stations, can produce a market development implementation plan. The study includes (1) background information on the National Photovoltaic Program, photovoltaic technology, and central stations; (2) a brief market assessment; (3) a discussion of the viewpoints of the electric utility industry with respect to solar energy; (4) a discussion of commercialization issues; and (5) strategy principles. It is recommended that a set of specific goals and objectives be defined for the photovoltaic central station program, and that these goals and objectives evolve into an implementation plan that identifies the appropriate federal role.

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NASA NTRS1982

Current NASA space station planning

Design considerations, trials, and actions both taken and necessary in the future which lead to the establishment of a space station by NASA are reviewed. Human performance on board Skylab demonstrated the feasibility and benefits of continuous operation of a space station. The manned orbital systems concept (MOSC) program, keeping in close contact with potential users, resulted in station requirements which included support for 720 day missions, up to four specialists per payload, 8-10 kW power, a 230 x 200 n mi altitude orbit, orbit change capability of 28.5 deg, all attitude orientation, and stability to within 1,100,000 g. Although the concept will not be funded, it provides a guide for incremental growth of a manned station from previously unmanned science platforms. Initiation of hardware development is projected for 1984-85. The agencies, both domestic and international, and missions for which the station will be built, are discussed.

Culbertson, P. E.↗
NASA NTRS1982

Requirements for a space station

Near-term requirements which will guide the design of a manned space station in near-earth orbit are considered. A primary focus will be establishing a base for astronomical observations which demand long term integration times. Earth observation systems such as the thematic mappers and SAR can be utilized by a free flyer in sunsynchronous orbit. Biological experiments can be carried out only with pressurized modules, ultimately large enough for humans habitation. At first, expendables would be ferried up from earth, while over time the space station would become a closed-loop system. An orbital transfer vehicle is necessary for the repair of satellites stationed in higher energy orbits. The operations of the station would include checking out communications satellites before boost into GEO. Finally, the station would be the final staging point for interplanetary and/or asteroid intercept missions.

Herman, D. H.↗
NASA NTRS1983

Targeting space station technologies

NASA's Space Station Technology Steering Committee has undertaken the definition of the level of technology that is desirable for use in the initial design and operation of an evolutionary, long service life space station, as well as the longer term technology required for the improvement of capabilities. The technology should initially become available in 1986, in order to support a space station launch as early as 1990. Toward this end, the committee seeks to assess technology forecasts based on existing research and testing capacity, and then plan and monitor a program which will move current technology to the requisite level of sophistication and reliability. The Space Shuttle is assumed to be the vehicle for space station delivery, assembly, and support on a 90-day initial cycle. Space station tasks will be military, commercial, and scientific, including on-orbit satellite servicing.

Olstad, W. B.↗
NASA NTRS1983

Space-station crew-safety requirements

Baseline rescue and survival concepts for future space station crews are described. Preliminary studies are being carried out to identify potential threats to crew safety and means to counteract the dangers. Significant factors being considered include the type of threat, the warning time, the number of crewmembers, strategies for protection of the crew (including life-support measures redundancy), and the dependence of space station crews on ground personnel. Attention is being given to the impact of safety devices on the space station geometry and cost, as well as the equipment necessary to maintain the crew in a psychological status positive enough to cope with emergencies. Typical threats would be fire, crewmember illness or injury, and abandonment of the station. A Shuttle launch could take up to 12 days, while equipping the space station with an emergency return capsule would permit return on the same day as the capsule was occupied.

Witcofski, R. D.↗
NASA NTRS1983

Space station architectural issues - The view from science

The evolution from current missions in space from Shuttle-directed to space station-directed is projected, with consideration given to space station missions that will affect the station architecture. The Shuttle science mission is basically to support astronomy and astrophysics work into the 1990s, particularly in launching and refurbishing satellites such as the SMM, the Space Telescope, and the Gamma Ray Observatory. Various new observational facilities are being planned and may be carried by the Shuttle for assembly in orbit. The assembly crews could live on a space station if sufficient capabilities and size were built into the station. The construction of large instruments in orbit, instruments that cannot be launched by any current booster, could permit enough data to be gathered to successfully characterize the evolution of the Universe.

Mcdonald, F. B.↗
NASA NTRS1983

Space station architectural concepts and functional capability

Space program goals that NASA can best achieve by the construction of a space station in keeping with the 1958 directive to maintain U.S. pre-eminence in space technology are discussed. Science goals that can be satisfied by a suitable equipped space station include a deeper understanding of the earth/sun system and the earth as a planet, the acquisition of new data on the evolution of the solar system, of life, and of the universe, and the extended study of the laws governing the state of matter and energy. Application goals that can be pursued with a space station include assaying all renewable and nonrenewable earth resources, predicting environment, weather, and climatic changes, studying ocean dynamics, using space to develop new processes and materials, and using space for information transmission on a global basis. The space station can serve as a waypoint for voyages by manned or unmanned spacecraft, as a laboratory, observation platform, and technology proving station, and as a base for deployment and repair of other spacecraft.

Herman, D. H.↗
NASA NTRS1983

Energy consumption analysis of the Venus Deep Space Station (DSS-13)

This report continues the energy consumption analysis and verification study of the tracking stations of the Goldstone Deep Space Communications Complex, and presents an audit of the Venus Deep Space Station (DSS 13). Due to the non-continuous radioastronomy research and development operations at the station, estimations of energy usage were employed in the energy consumption simulation of both the 9-meter and 26-meter antenna buildings. A 17.9% decrease in station energy consumption was experienced over the 1979-1981 years under study. A comparison of the ECP computer simulations and the station's main watt-hour meter readings showed good agreement.

Hayes, N. V.↗
NASA NTRS1982

A study of space station needs, attributes and architectural options. Midterm briefing, executive summary

The approach used to develop a broad interest in the space station within the commercial and DoD communities is outlined. Areas of maximum benefit from a space station were identified and the associated economic benefits were quantified. Results show that the space station can provide major performance benefits for 82 man-operated missions, 18 man-tended free flyer missions, and 46 OTV missions. The man-operated OVT-based benefits are $800 M per year. The cost of shuttle flights of all STS users can be reduced by $7 M per flight. The economic benefits quantified to date exceed 1.3 B per year. Combined NASA/DoD utilization of an initial space station provided economic and technical benefits. Preliminary studies of operational missions indicate a possible need for separate stations.

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NASA NTRS1983

Space station: Cost and benefits

Costs for developing, producing, operating, and supporting the initial space station, a 4 to 8 man space station, and a 4 to 24 man space station are estimated and compared. These costs include contractor hardware; space station assembly and logistics flight costs; and payload support elements. Transportation system options examined include orbiter modules; standard and extended duration STS fights; reusable spacebased perigee kick motor OTV; and upper stages. Space station service charges assessed include crew hours; energy requirements; payload support module storage; pressurized port usage; and OTV service facility. Graphs show costs for science missions, space processing research, small communication satellites; large GEO transportation; OVT launch costs; DOD payload costs, and user costs.

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NASA NTRS1984

Petrologic comparisons of Cayley and Descartes on the basis of Apollo 16 soils from stations 4 and 11

Petrologic aspects of the Cayley and Descartes formations are reviewed in the light of new data on Apollo 16 soils. Specific comparison of the modal abundances of lithic fragments in drive tube sample 64001/2 from the slopes of Stone Mountain (station 4) and in soil 67941 from the North Ray Crater rim (station 11) shows that melt rocks, especially poikilitic rocks, are more abundant at station 4 than at station 11; the reverse is true for fragmental breccias. Such lithologic differences suggest that stations 4 and 11 do not belong to the same geologic formation. Metamorphosed breccias are pervasive in both the formations and may represent a local component that has been reworked and diluted as fresh materials were added. Lithologic compositions inferred from the study of soil samples are different from lithologic compositions inferred from the study of rake samples or breccia clasts. This difference may be related to a mixing of material of different grain size distributions. The petrology of soils at the Apollo 16 site may not accurately reflect original material associated with either the Descartes or the Cayley formation because of extensive mixing with local material.

Basu, A.↗
NASA NTRS1984

Concept for a commercial space station laboratory

The concept of a privately owned and operated fee-for-service laboratory as an element of a civil manned space station, envisioned as the venture of a group of private investors and an experienced laboratory operator to be undertaken with the cooperation of NASA is discussed. This group would acquire, outfit, activate, and operate the labortory on a fee-for-service basis, providing laboratory services to commercial firms, universities, and government agencies, including NASA. This concept was developed to identify, stimulate, and assist potential commercial users of a manned space station. A number of the issues which would be related to the concept, including the terms under which NASA might consider permitting private ownership and operation of a major space station component, the policies with respect to international participation in the construction and use of the space station, the basis for charging users for services received from the space station, and the types of support that NASA might be willing to provide to assist private industry in carrying out such a venture are discussed.

Wood, P. W.↗
NASA NTRS1985

An evaluation of oxygen-hydrogen propulsion systems for the Space Station

Conceptual designs for O2/H2 chemical and resistojet propulsion systems for the space station was developed and evaluated. The evolution of propulsion requirements was considered as the space station configuration and its utilization as a space transportation node change over the first decade of operation. The characteristics of candidate O2/H2 auxiliary propulsion systems are determined, and opportunities for integration with the OTV tank farm and the space station life support, power and thermal control subsystems are investigated. OTV tank farm boiloff can provide a major portion of the growth station impulse requirements and CO2 from the life support system can be a significant propellant resource, provided it is not denied by closure of that subsystem. Waste heat from the thermal control system is sufficient for many propellant conditioning requirements. It is concluded that the optimum level of subsystem integration must be based on higher level space station studies.

Klemetson, R. W.↗
NASA NTRS1985

Space station dynamic modeling, disturbance accommodation, and adaptive control

Dynamic models for two space station configurations were derived. Space shuttle docking disturbances and their effects on the station and solar panels are quantified. It is shown that hard shuttle docking can cause solar panel buckling. Soft docking and berthing can substantially reduce structural loads at the expense of large shuttle and station attitude excursions. It is found predocking shuttle momentum reduction is necessary to achieve safe and routine operations. A direct model reference adaptive control is synthesized and evaluated for the station model parameter errors and plant dynamics truncations. The rigid body and the flexible modes are treated. It is shown that convergence of the adaptive algorithm can be achieved in 100 seconds with reasonable performance even during shuttle hard docking operations in which station mass and inertia are instantaneously changed by more than 100%.

Wang, S. J.↗
NASA NTRS1985

Structural dynamics model and response of the deployable reference configuration space station

The analytical models and results of a structural dynamics investigation of the reference initial operation and evolutionary configurations of the nine foot bay space station are presented. This investigation was carried out between April and August 1984 as part of a team effort to define a reference configuration for the first U.S. manned space station. The results presented herein serve as a guide, a point of departure and a standard for future NASA and contractor studies leading to the design of the Space Station. The reference initial operation configuration of the nine foot bay station was found to be very flexible, with its lowest mode between 0.096 and 0.138 Hertz depending on station attachments. However, for the transient load cases which were then available, internal member loads had positive margins of safety and preliminary results indicate that laboratory experiments which require quiescent conditions can be satisfied down to the order of 0.0001 g's.

Housner, J. M.↗
NASA NTRS1985

Space Station Engineering and Technology Development: Proceedings of the Panel on In-Space Engineering Research and Technology Development

In 1984 the ad hoc committee on Space Station Engineering and Technology Development of the Aeronautics and Space Engineering Board (ASEB) conducted a review of the National Aeronautics and Space Administration's (NASA's) space station program planning. The review addressed the initial operating configuration (IOC) of the station. The ASEB has reconstituted the ad hoc committee which then established panels to address each specific related subject. The participants of the panels come from the committee, industry, and universities. The proceedings of the Panel on In Space Engineering Research and Technology Development are presented in this report. Activities, and plans for identifying and developing R&T programs to be conducted by the space station and related in space support needs including module requirements are addressed. Consideration is given to use of the station for R&T for other government agencies, universities, and industry.

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NASA NTRS1985

Applicability of 100kWe-class of space reactor power systems to NASA manned space station missions

An assessment is made of a manned space station operating with sufficiently high power demands to require a multihundred kilowatt range electrical power system. The nuclear reactor is a competitor for supplying this power level. Load levels were selected at 150kWe and 300kWe. Interactions among the reactor electrical power system, the manned space station, the space transportation system, and the mission were evaluated. The reactor shield and the conversion equipment were assumed to be in different positions with respect to the station; on board, tethered, and on a free flyer platform. Mission analyses showed that the free flyer concept resulted in unacceptable costs and technical problems. The tethered reactor providing power to an electrolyzer for regenerative fuel cells on the space station, results in a minimum weight shield and can be designed to release the reactor power section so that it moves to a high altitude orbit where the decay period is at least 300 years. Placing the reactor on the station, on a structural boom is an attractive design, but heavier than the long tethered reactor design because of the shield weight for manned activity near the reactor.

Silverman, S. W.↗