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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 1,243 records · Page 69
All sourcesNASA NTRSDOE OSTI
NASA NTRS1981

A 102 cm balloon-borne telescope for far-infrared astronomical observations

In early 1971, a program was initiated to develop a balloon-borne 102-cm telescope, capable of carrying out far-infrared observations of astronomical interest above the earth's atmosphere in the wavelength range from 40 to 250 micrometers. Since 1972 the telescope has been flown and successfully recovered a total of sixteen times. Ten of the flights have produced high quality astronomical data, resulting in more than 80 hours of photometric and spectroscopic observations of numerous objects, such as H II regions, dark clouds, molecular clouds, X-ray sources, galaxies, the galactic center, planets, the Moon, and an asteroid. Attention is given to the telescope optics, the gondola, altitude control, the auxiliary attitude control system, the determination of telescope pointing position, telemetry, power requirements, the flight record, and the four instruments which are available for use on the balloon-borne telescope.

Fazio, G. G.↗
NASA NTRS1981

Technology for large space systems: A special bibliography with indexes (supplement 05)

This bibliography lists 298 reports, articles, and other documents introduced into the NASA scientific and technical information system between January 1, 1981 and June 30, 1981. Its purpose is to provide helpful, information to the researcher, manager, and designer in technology development and mission design in the area of the Large Space Systems Technology (LSST) Program. Subject matter is grouped according to systems, interactive analysis and design, structural concepts, control systems, electronics, advanced materials, assembly concepts, propulsion, solar power satellite systems, and flight experiments.

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NASA NTRS1980

A study of universal modulation techniques applied to satellite data collection

A universal modulation and frequency control system for use with data collection platform (DCP) transmitters is examined. The final design discussed can, under software/firmwave control, generate all of the specific digital data modulation formats currently used in the NASA satellite data collection service and can simultaneously synthesize the proper RF carrier frequencies employed. A novel technique for DCP time and frequency control is presented. The emissions of NBS radio station WWV/WWVH are received, detected, and finally decoded in microcomputer software to generate a highly accurate time base for the platform; with the assistance of external hardware, the microcomputer also directs the recalibration of all DCP oscillators to achieve very high frequency accuracies and low drift rates versus temperature, supply voltage, and time. The final programmable DCP design also employs direct microcomputer control of data reduction, formatting, transmitter switching, and system power management.

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NASA NTRS1982

The tethered retrievable platform concept and utilization

Main components of the current configuration of a proposed tethered satellite system (TSS) for deploying instrumentation up to 100 km upward or downward from the Orbiter in LEO are described. The TSS consists of the Deployer Module, the Tether, and the Satellite Module, and remains connected to the equipment in the Orbiter bay for the entire mission. The Deployer Module is mounted on a pallet, and has a boom, a tether control mechanism, and a tether control capability, in addition to data acquisition and control systems. The Satellite Module features a thermal control, electrical power and distribution, data management and communication, attitude determination, propulsion, and payload capability. Deployment is unpowered, taking advantage instead of gravity gradients to move the payload from the Orbiter. Safety features include a cutter mechanism to disengage the tether from the Orbiter if retrieval of the payload is judged to endanger the crew and the Orbiter.

Laue, J. H.↗
NASA NTRS1982

Technology for large space systems: A special bibliography with indexes (supplement 06)

This bibliography lists 220 reports, articles and other documents introduced into the NASA scientific and technical information system between July 1, 1981 and December 31, 1981. Its purpose is to provide helpful information to the researcher, manager, and designer in technology development and mission design in the area of the Large Space Systems Technology (LSST) Program. Subject matter is grouped according to systems, interactive analysis and design, structural concepts, control systems, electronics, advanced materials, assembly concepts, propulsion, solar power satellite systems, and flight experiments.

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NASA NTRS1983

Technology for large space systems: A bibliography with indexes (supplement 07)

This bibliography lists 366 reports, articles and other documents introduced into the NASA scientific and technical information system between January 1, 1982 and June 30, 1982. Subject matter is grouped according to systems, interactive analysis and design, structural concepts, control systems, electronics, advanced materials, assembly concepts, propulsion, solar power satellite systems, and flight experiments.

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NASA NTRS1983

Qualification testing for a central station

Qualification testing for a Central Station Photovoltaic (PV) Facility depends to a great extent on the system design, (fixed versus tracking), and the level of data acquisition/control which is incorporated into the system. The basic elements which require qualification tests include: dc power production/collection; tracker conversion systems; ac utility interface; system level control; and data acquisition/reporting. The qualification tests from the Lungo (ARCO) 1 MW Facility which were completed in January 1983 are discussed. The philosophy and many of the procedures are applicable to any central station PV facility.

Forrester, D. L.↗
NASA NTRS1984

Integrated technology wing design study

The technology development costs and associated benefits in applying advanced technology associated with the design of a new wing for a new or derivative trijet with a capacity for 350 passengers and maximum range of 8519 km, entering service in 1990 were studied. The areas of technology are: (1) airfoil technology; (2) planform parameters; (3) high lift; (4) pitch active control system; (5) all electric systems; (6) E to 3rd power propulsion; (7) airframe/propulsion integration; (8) graphite/epoxy composites; (9) advanced aluminum alloys; (10) titanium alloys; and (11) silicon carbide/aluminum composites. These technologies were applied to the reference aircraft configuration. Payoffs were determined for block fuel reductions and net value of technology. These technologies are ranked for the ratio of net value of technology (NVT) to technology development costs.

Hays, A. P.↗
NASA NTRS1985

Space shuttle flight readiness firing dress rehearsal for STS-1

The static firing of the Space Shuttle Main Engine in preparation for the launch of the Enterprise Orbiter is discussed. The following were also tested: structures and mechanics; thermal design integration; propulsion and power; avionics and software; guidance, navigation, and control; mechanical systems; communications and tracking; and integrated ground systems.

Riles, W. L.↗
NASA NTRS1986

A 25-kW Series-Resonant Power Converter

Prototype exhibited efficiency of 93.9 percent. 25-kW resonant dc/dc power converter designed, developed, fabricated, and tested, using Westinghouse D7ST transistors as high-power switches. D7ST transistor characterized for use as switch in series-resonant converters, and refined base-drive circuit developed. Technical base includes advanced switching magnetic, and filter components, mathematical circuit models, control philosophies, and switch-drive strategies. Power-system benefits such as lower losses when used for high-voltage distribution, and reduced magnetics and filter mass realized.

Frye, R. J.↗
NASA NTRS1985

A new direction in energy conversion - The all-electric aircraft

This paper reviews recent studies of all-electric aircraft that use electric-only secondary power and flight critical fly-by-wire flight controls, and brings to the attention of the power system designer the intrinsic advantages of such aircraft. The all-electric aircraft is made possible by the development of rare earth magnet materials and fault tolerant systems technologies. Recent studies have shown all-electric aircraft to be more efficient than conventional designs and offer substantial operating costs reductions. Compared to present aircraft, an all-electric transport can save at least 10 percent in fuel burn. The cornerstone of an all-electric aircraft is the electric secondary power system. This paper reviews the major features of flight critical electric secondary power systems. Research required to lay the foundation for an all-electric aircraft is briefly discussed.

Spitzer, C. R.↗
NASA NTRS1985

A two-dimensional near-infrared tracking system

Video tracking systems face the problem of discriminating between a target in space and the earth in the background. The visual tracking system described in this paper uses the near-infrared to take advantage of differences in spectral reflectance between the target and the earth in the background to enhance amplitude differences, simplifying the detection process. The real-time visual tracking system is microprocessor controlled, light weight, and low-power.

Walton, D. P.↗
NASA NTRS1988

Personnel occupied woven envelope robot

The Personnel Occupied Woven Envelope Robot (POWER) provides an alternative to extravehicular activity (EVA) of space suited astronauts and/or use of long slender manipulator arms such as are used in the Shuttle Remote Manipulator System. POWER provides the capability for a shirt sleeved astronaut to perform such work by entering a control pod through air locks at both ends of an inflated flexible bellows (access tunnel). The exoskeleton of the tunnel is a series of six degrees of freedom (Six-DOF) articulated links compressible to 1/6 of their fully extended length. The operator can maneuver the control pod to almost any location within about 50 m of the base attachment to the space station. POWER can be envisioned as a series of hollow Six-DOF manipulator segments or arms wherein each arm grasps the shoulder of the next arm. Inside the hollow arms ia a bellow-type access tunnel. The control pod is the fist of the series of linked hollow arms. The fingers of the fist are conventional manipulator arms under direct visual control of the nearby operator in the pod. The applications and progress to date of the POWER system is given.

Wessling, Francis↗
NASA NTRS1987

Flight research with the MIT Daedalus prototype

The MIT Light Eagle human-powered aircraft underwent long-duration testing over Rogers Dry Lake in California during January, 1987. Designed as a prototype for the MIT Daedalus Project, the Light Eagle's forty-eight flights provided pilot training, established new distance records for human-powered flight, and provided quantitative data through a series of instrumented flight experiments. The experiments focused on: (1) evaluating physiological loads on the pilot, (2) determining airframe power requirements, and (3) developing an electronic flight control system. This paper discusses the flight test program, its results and their implications for the follow-on Daedalus aircraft, and the potential uses of the Light Eagle as a low Reynolds number testbed.

Bussolari, Steven R.↗
NASA NTRS1987

A long-duration balloon payload for hard X-ray and gamma-ray observations of the sun

A balloon payload designed to study the processes of energy release, particle acceleration, and heating of the active corona in hard X-ray microflares and normal flares is described. An array of liquid nitrogen-cooled germanium detectors together with large area phoswich scintillation detectors provide the highest sensitivity (about 500 sq cm) and energy resolution (not greater than 0.7 keV) ever achieved for solar hard X-ray (about 15-600 keV) measurements. These detectors were flown in February 1987 from Australia on a long duration radiation controlled balloon flight (LDBF) which provided 12 days of observations before cutdown in Brazil. The payload includes solar cells for power, pointing, and navigation sensors, a microprocessor controlled data system with VCR tape storage, and transmitters for GOES and ARGOS spacecraft. This successful flight illustrates the potential of LDBFs for solar flare studies.

Lin, R. P.↗
NASA NTRS1988

Adaption of Space Station technology for lunar operations

The possible use of Space Station technology in a lunar base program is discussed, focusing on the lunar lander/ascent vehicles and surface modules. The application of the Space Station data management system, software, and communications, tracking, guidance, navigation, control, and power technologies is examined. The benefits of utilizing this technology for lunar operations are considered.

Garvey, J. M.↗
NASA NTRS1989

Apollo Lightcraft Project

The ultimate goal for this NASA/USRA-sponsored Apollo Lightcraft Project is to develop a revolutionary manned launch vehicle technology which can potentially reduce payload transport costs by a factor of 1000 below the Space Shuttle Orbiter. The Rensselaer design team proposes to utilize advanced, highly energetic, beamed-energy sources (laser, microwave) and innovative combined-cycle (airbreathing/rocket) engines to accomplish this goal. The research effort focuses on the concept of a 100 MW-class, laser-boosted Lightcraft Technology Demonstrator (LTD) drone. The preliminary conceptual design of this 1.4 meter diameter microspacecraft involved an analytical performance analysis of the transatmospheric engine in its two modes of operation (including an assessment of propellant and tankage requirements), and a detailed design of internal structure and external aeroshell configuration. The central theme of this advanced propulsion research was to pick a known excellent working fluid (i.e., air or LN sub 2), and then to design a combined-cycle engine concept around it. Also, a structural vibration analysis was performed on the annular shroud pulsejet engine. Finally, the sensor satellite mission was examined to identify the requisite subsystem hardware: e.g., electrical power supply, optics and sensors, communications and attitude control systems.

Myrabo, Leik N.↗
NASA NTRS1990

Publications of the NASA Controlled Ecological Life Support System (CELSS) Program, 1979-1989

Publications of research sponsored by the NASA Controlled Ecological Life Support System (CELSS) Program from 1979 to 1989 are listed. The CELSS Program encompasses research and technology with the goal of developing an autonomous bioregenerative life support system that continually recycles the solid, liquid, and gaseous materials essential for human life. The bibliography is divided into four major subject areas: food production, nutritional requirements, waste management, and systems management and control.

Wallace, Janice S.↗