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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 469 records · Page 26
All sourcesNASA NTRSDOE OSTI
NASA NTRS1986

The Space Transportation System

The accomplishments and present budget concerns of the Space Transportation System (STS) program are discussed. The Shuttle, with the most advanced operational engine in the world and the largest rocket motor and external tank ever developed, is shown to be a successful, state-of-the-art achievement with enormous capabilities for future exploitation. The readjusted price of $71M (1982$) for a dedicated mission for the period FY 86-FY 88 is nearly twice the price estimated at the beginning of the 12-year program. Additional flights above the sixteen plus missions necessary for the U.S. government's NASA and DOD National Security payloads, are offered to U.S. and foreign, commercial and civil customers, to help recover the marginal costs of anticipated future payloads. Aspects of the present bid scheme, with a $74.0M (82$) minimum bid commencing with FY 1989, are discussed.

Lee, C. M.↗
NASA NTRS1985

National space transportation systems planning

In the fall of 1984, the DOD and NASA had been asked to identify launch vehicle technologies which could be made available for use in 1995 to 2010. The results of the studies of the two groups were integrated, and a consumer report, dated December 1984, was forwarded to the President. Aspects of mission planning and analysis are discussed along with a combined mission model, future launch system requirements, a launch vehicle planning background, Shuttle derivative vehicle program options, payload modularization, launch vehicle technology implications, a new engine program for the mid-1990's. Future launch systems goals are to achieve an order of magnitude reduction in future launch cost and meet the lift requirements and launch rates. Attention is given to an advanced cryogenic engine, advanced LOX/hydrocarbon engine, advanced power systems, aerodynamics/flight mechanics, reentry/recovery systems, avionics/software, advanced manufacturing techniques, autonomous ground and mission operations, advanced structures/materials, and air breathing propulsion.

Lucas, W. R.↗
NASA NTRS1986

Precise positioning capabilities for TOPEX using differential GPS

NASA's Ocean Topographic Experiment (TOPEX), to be launched in 1991, is the first mission designed to reach the decimeter accuracy needed for the solution of the general mean circulation problem. An experimental tracking capability for TOPEX is studied using differential measurements with satellites of the U.S. DOD's Global Positioning System (GPS). Two data types are studied: (1) integrated Doppler from GPS carrier phase, and (2) GPS P-code pseudo-range. Results of covariance analysis predict that with differential GPS techniques, 5-10 cm average TOPEX altitude accuracies can be achieved over data arcs of two hours.

Lichten, S. M.↗
NASA NTRS1986

Space Shuttle development

The technical-planning and decision-making processes involved in the initiation of the NASA Space Shuttle program in 1970-1972 are briefly discussed, responding to the critical evaluation of Logsdon (1986). The complex nature of the interactions among White House, OMB, DOD, and NASA; the difficulty of making long-term commitments under the U.S. system; the positive technological achievements of the program; and the need for unemotional evaluation of the policy options available after the loss of the Challenger are stressed. In a reply by Logsdon, it is argued that the structuring of the policy process itself and the presentation of the Shuttle to Congress as a relatively inexpensive routine launch system for virtually all government needs were directly related to its failure to gain continuing full funding from Administrations and Congress. It is suggested that a strong proposal of bold scientific and exploratory objectives for the space program could be more successful in gaining such long-term support.

Fletcher, J. C.↗
NASA NTRS1986

Spacecraft Dynamics and Control Program at AFRPL

A number of future DOD and NASA spacecraft such as the space based radar will be not only an order of magnitude larger in dimension than the current spacecraft, but will exhibit extreme structural flexibility with very low structural vibration frequencies. Another class of spacecraft (such as the space defense platforms) will combine large physical size with extremely precise pointing requirement. Such problems require a total departure from the traditional methods of modeling and control system design of spacecraft where structural flexibility is treated as a secondary effect. With these problems in mind, the Air Force Rocket Propulsion Laboratory (AFRPL) initiated research to develop dynamics and control technology so as to enable the future large space structures (LSS). AFRPL's effort in this area can be subdivided into the following three overlapping areas: (1) ground experiments, (2) spacecraft modeling and control, and (3) sensors and actuators. Both the in-house and contractual efforts of the AFRPL in LSS are summarized.

Das, A.↗
NASA NTRS1986

Overview of the 1986 free-piston Stirling activities at NASA Lewis Research Center

An overview of the NASA Lewis Research Center's free-piston Stirling engine research is presented, including efforts to improve and advance its design for use in specific space power applications. These efforts are a part of the SP-100 program being conducted to support the Department of Defense (DOD), Department of Energy (DOE) and NASA. Such efforts include: (1) the testing and improvement of 25 kWe Stirling Space Power Demonstrator Engine (SPDE); (2) the preliminary design of 25 kWe single-cylinder Experimental stirling Space Engine (ESSE); and, (3) a study to determine the feasibility of scaling a single-cylinder free-piston Stirling engine/linear alternator to 150 kWe. Other NASA Lewis free-piston Stirling engine activities will be described, directed toward the advancement of general free-piston Stirling engine technology and its application in specific terrestrial applications. One such effort, supported by DOE/Oak Ridge National Laboratory (DRNL), is the development of a free-piston Stirling engine which produces hydraulic power. Finally, a terrestrial solar application involving a conceptual design of a 25 kWe Solar Advanced Stirling Conversion System (ASCS) capable of delivering power to an electric utility grid will be discussed. The latter work is supported by DOE/Sandia National Laboratory (SNLA).

Alger, Donald L.↗
NASA NTRS1986

An evaluation of the documented requirements of the SSP UIL and a review of commercial software packages for the development and testing of UIL prototypes

A review was conducted of software packages currently on the market which might be integrated with the interface language and aid in reaching the objectives of customization, standardization, transparency, reliability, maintainability, language substitutions, expandability, portability, and flexibility. Recommendations are given for best choices in hardware and software acquisition for inhouse testing of these possible integrations. Software acquisition in the line of tools to aid expert-system development and/or novice program development, artificial intelligent voice technology and touch screen or joystick or mouse utilization as well as networking were recommended. Other recommendations concerned using the language Ada for the user interface language shell because of its high level of standardization, structure, and ability to accept and execute programs written in other programming languages, its DOD ownership and control, and keeping the user interface language simple so that multiples of users will find the commercialization of space within their realm of possibility which is, after all, the purpose of the Space Station.

Gill, Esther Naomi↗
NASA NTRS1986

Ground facility for large space structures dynamics and control verification

NASA Marshall Space Flight Center has developed a facility in which closed loop control of Large Space Structures (LSS) can be demonstrated and verified. The main objective of the facility is to verify LSS control system techniques so that on-orbit performance can be unsured. The facility consists of an LSS test article or payload which is connected to a 3-axis angular pointing mount assembly that provides control torque commands. The angular pointing mount assembly is attached to a base excitation system which will simulate disturbances most likely to occur for Orbiter and DOD payloads. The control computer contains the calibration software, the reference systems, the alignment procedures, the telemetry software, and the control algorithms. The total system is suspended in such a fashion that the LSS test article has the characteristics common to all LSS.

Waites, Henry↗
NASA NTRS1986

Orbital transfer vehicle concept definition and system analysis study. Volume 1A: Executive summary. Phase 2

The objectives of the Phase 2 study were to improve the orbit transfer vehicle (OTV) concept definition by focusing on the following issues: the impact of mission requirements on OTV system design; OTV basing concepts on the Space Shuttle, separate platforms, and/or remote locations; cost reduction of an OTV program to improve its economic benefits and support its acquisition. The OTV mission scenario includes a wide range of missions the main drivers of which are manned GEO servicing, mid-inclination/polar DOD, and lunar/planetary projects. A mission model is presented which includes the type and number of missions per year and the estimated propellant requirements. To accomplish the missions, many OTV concepts were defined including ground-based OTVs launched either in the STS orbiter, the aft cargo carrier, or a heavy lift launch vehicle, and a space-based OTV. System and program trade studies were conducted using performance, cost, safety/risk, and operations/growth criteria. The study shows that mission requirements and substantial economic benefits justify a reusable, cryogenic (H2/O2) space-based OTV. Such a system would not be subjected to Earth-to-orbit launch loads and would not be constained in size or weight. Safety is enhanced by the fact that the system components are launched unfueled. Its inherent reusability and ability to be refueled in space make the space-based OTV very economical to operate.

Ketchum, W. J.↗
NASA NTRS1987

Overview: Fluid acquisition and transfer

This brief overview introduced the symposium session on microgravity fluid acquisition and transfer. It states the objective of NASA efforts in this technology and the approach being taken in the technology program. The problems are outlined and various methods for low-gravity fluid acquisition and transfer are summarized. Applications for the technology are described and an assessment of the current state of the art is presented. NASA and DOD on-going and planned programs are listed.

Meserole, Jere S.↗
NASA NTRS1987

Large space structures ground experiment checkout

NASA Marshall Space Flight Center has developed a facility in which closed loop control of Large Space Structures (LSS) can be demonstrated and verified. The main objective of the facility is to verify LSS control system techniques so that on-orbit performance can be ensured. The facility consists of an LSS test article or payload which is connected to a 3-axis angular pointing mount assembly that provides control torque commands. The angular pointing mount assembly is attached to a base excitation system which will simulate disturbances most likely to occur for Orbiter and DOD payloads. The control computer contains the calibration software, the reference systems, the alignment procedures, the telemetry software, and the control algorithms. The total system is suspended in such a fashion that the LSS test article has the characteristics common to all LSS.

Waites, Henry B.↗
NASA NTRS1987

Component variations and their effects on bipolar nickel-hydrogen cell performance

A 50 cell bipolar nickel-hydrogen battery was assembled to demonstrate the feasibility of constructing a high voltage stack of cells. Various component combinations were tested in this battery. The battery had approximately 1 ampere-hour of capacity and was constructed from components with an active area of 2" X 2". The components were parametrically varied to give a comparison of nickel electrodes, hydrogen electrodes, separators, fill procedures and electrolyte reservoir plate thicknesses. Groups of five cells were constructed using the same components; ten combinations were tested in all. The battery was thoroughly characterized at various change and discharge rates as well as with various pulse patterns and rates. Over a period of 1400 40% DOD LEO cycles some of the groups began to exhibit performance differences. In general, only separator variations had a significant effect on cell performance. It also appears that shunt currents may have been operating within the stack, resulting in electrolyte transfer from one cell to another, thus contributing to cell performance variations.

Manzo, Michelle A.↗
NASA NTRS1987

NASA/DOD Control/Structures Interaction Technology, 1986

Papers presented at the CSI Technology Conference are given. The conference was jointly sponsored by the NASA Office of Aeronautics and Space Technology and the Department of Defense. The conference is the beginning of a series of annual conferences whose purpose is to report to industry, academia, and government agencies the current status of Control/Structures Interaction technology. The conference program was divided into five sessions: (1) Future spacecraft requirements; Technology issues and impact; (2) DOD special topics; (3) Large space systems technology; (4) Control of flexible structures, and (5) Selected NASA research in control structures interaction.

Wright, Robert L.↗
NASA NTRS1986

Historical data retrieval study - Results for the first five years of KSC STS payload processing

This paper identifies general and specific quantitative and qualitative results from a study of actual operational experiences while processing 185 science, applications, and commercial payloads for the first five years of STS operations at NASA's Kennedy Space Center (KSC). All the non-DOD payloads from STS-2 through STS-33 were part of the study. The emphasis was placed on various program planning and events that affected KSC processing, payload experiences and improvements, payload hardware condition after arrival, services to customers, and the impact of STS operations and delays. From these initial considerations, operational drivers were identified, data for selected processing measurements collected and analyzed, processing criteria and options determined, and STS payload results and conclusions reached. The study showed a significant reduction in time and effort needed by STS customers and KSC to process a wide variety of payload configurations, although even the simplest payloads required more processing resources and time than were initially assumed.

Ragusa, J. M.↗
NASA NTRS1986

Overview of the 1986 free-piston Stirling SP-100 activities at the NASA Lewis Research Center

An overview of the NASA Lewis Research Center SP-100 free-piston Stirling engine activities is presented. These activities include a free-piston Stirling space-power technology feasibility demonstration project as part of the SP-100 program being conducted in support of the Department of Defennse (DOD), Department of Energy (DOE), and NASA. The space-power Stirling advanced technology effort, under SP-100, addresses the status of the 25 kWe Space Power Demonstrator Engine (SPDE) including test results. Future space-power projections are presented along with a description of a study that will investigate the feasibility of scaling a single-cylinder free-piston Stirling space-power module to the 150 kW power range. Design parameters and conceptual design features will be presented for a 25 kWe, single-cylinder free-piston Stirling space-power converter. A description of a hydrodynamic gas bearing concept is presented whereby the displacer of a 1 kWe free-piston Stirling engine is modified to demonstrate the bearing concept. And finally the goals of a conceptual design for a 25 kWe Solar Advanced Stirling Conversion System capable of delivering electric power to an electric utility grid are discussed.

Slaby, J. G.↗
NASA NTRS1986

Effect of impregnation method on cycle life of the nickel electrode

The nickel electrode has been identified as the life limiting component for individual pressure vessel (IPV) nickel-hydrogen cells when cycled under a low earth orbit (LEO) cycle regime at deep depths of discharge. As a part of an overall program to develop a long life nickel electrode for nickel-hydrogen cells, the effect of two different methods of electrochemical impregnation on the cycle life of the nickel electrode was investigated. One method was the Pickett (aqueous/ethanolic) process. The other was the modified Bell (aqueous) process. The plaques for both impregnation methods were made by sintering dry carbonyl nickel powder in a reducing atmosphere. The plaques contain a nickel screen substrate. Electrodes made from both processes were cycle tested in Air Force design IPV nickel-hydrogen cells. The only factor different for this test was the method of plaque impregnation; all other factors were the same. The cells were cycled to failure under a 90 min LEO cycle regime at a deep depth of discharge (80 percent DOD). Failure for this test was defined to occur when the cell voltage degraded to 1.0 V prior to the completion of the 35 min discharge.

Smithrick, J. J.↗
NASA NTRS1986

Ground facility for Large Space Structures dynamics and control verification

NASA Marshall Space Flight Center has developed a facility in which closed loop control of Large Space Structures (LSS) can be demonstrated and verified. The main objective of the facility is to verify LSS control system techniques so that on-orbit performance can be ensured. The facility consists of an LSS test article or payload which is connected to a 3-axis angular pointing mount assembly that provides control torque commands. The angular pointing mount assembly is attached to a base excitation system which will simulate disturbances most likely to occur for Orbiter and DOD payloads. The control computer contains the calibration software, the reference systems, the alignment procedures, the telemetry software, and the control algorithms. The total system is suspended in such a fashion that the LSS test article has the characteristics common to all LSS.

Waites, Henry↗
NASA NTRS1987

Rekindled vision of hypersonic travel

NASA has joined with the DOD to conduct the National Aerospace Plane (NASP) program, whose experimental test vehicle will be designated the X-30. NASP will study the X-30's takeoff from a runway under its own power, acceleration to high Mach number on the basis of airbreathing propulsion, emergence into LEO, reentry into the earth atmosphere, and descent to a powered horizontal landing. NASP will thereby generate technology base data for three distinct types of aircraft: upper-atmosphere hypersonic-cruise aircraft, LEO space transports, and military transatmospheric vehicles. The current concept-validation phase of NASP focuses on airbreathing propulsion, lightweight/high-strength heat-resistant materials, and computational fluid dynamics.

Colladay, Raymond S.↗