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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 829 records · Page 46
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

Teleoperators - Manual/automatic system requirements.

The teleoperator is defined as a remotely controlled, cybernetic, man-machine system designed to extend and augment man's sensory, manipulative, and cognitive capabilities. The teleoperator system incorporates the decision making, adaptive intelligence without requiring its presence. The man and the machine work as a team, each contributing unique and significant capabilities, and each depending on the other to achieve a common goal. Some of the more significant requirements associated with the development of teleoperator systems technology for space, industry, and medicine are examined. Emphasis is placed on the requirement to more effectively use the man and the machine in any man-machine system.

Janow, C.↗
NASA NTRS1973

Shuttle-Attached Manipulator System requirements.

Shuttle mission requirements and cost objectives have led to the selection of a Shuttle-Attached Manipulator System (SAMS) as a general purpose mechanism for docking, payload handling, and the general launch and retrieval of free-flying satellites. SAMS design requirements are discussed, giving attention to end effectors, kinematics, timelines, dynamics, load ratings, TV cameras and lights. Requirements for low-cost payload satellites are considered, taking into account satellites with modular subsystems which are designed for replacement and for resupply in orbit by SAMS.

Bodey, C. E.↗
NASA NTRS1973

Advanced Pioneer guidance and navigation requirements for outer planet missions

Three advanced Pioneer missions to the outer planets are analyzed to assess midcourse velocity and navigation requirements. Selecting the results of the Saturn/Uranus mission as representative values for the three missions, the Earth-Saturn midcourse mean plus 3-sigma velocity correction is 80 m/sec. Earth-based radio-only tracking results in a navigational error of 2000 km at Saturn which in turn requires a mean plus 3-sigma velocity correction of 140 m/sec on the Saturn-Uranus leg to nullify this error mapped to Uranus. In contrast to these figures, if a proposed optical V-slit sensor is incorporated into the spacecraft navigational system, a Saturn B-plane error of only 350 km results with a corresponding required mean plus 3-sigma post-Saturn velocity correction of 23.2 m/sec. An 8000 km miss at Uranus results from radio-only tracking at Saturn which can be considerably reduced to 1400 km by utilizing the optical sensor during the Saturn flyby.

Paul, C. K.↗
NASA NTRS1974

Microwave landing system requirements for STOL operations

The operational/functional requirements for the new Microwave Landing System (MLS) are examined for STOL operations. The study utilizes a nonlinear six-degree-of-freedom simulation of a De Havilland Buffalo C-8A aircraft and automatic flight control system to assess the MLS/STOL accuracy, coverage, and data rate requirements for the azimuth, DME, primary elevation, and flare elevation functions. The aircraft performance is statistically determined for representative curved flight paths through touchdown. A range of MLS errors and coverages, environmental disturbances, and navigation filtering are investigated. The study indicates that STOL applications do not place any unique requirements on the MLS.

Burrous, C. N.↗
NASA NTRS1974

MEGASTAR: The Meaning of Energy Growth: An Assessment of Systems, Technologies, and Requirements

A methodology for the display and analysis of postulated energy futures for the United States is presented. A systems approach that includes the methodology of technology assessment is used to examine three energy scenarios--the Westinghouse Nuclear Electric Economy, the Ford Technical Fix Base Case and a MEGASTAR generated Alternate to the Ford Technical Fix Base Case. The three scenarios represent different paths of energy consumption for the present to the year 2000. Associated with these paths are various mixes of fuels, conversion, distribution, conservation and end-use technologies. MEGASTAR presents the estimated times and unit requirements to supply the fuels, conversion and distribution systems for the postulated end uses for the three scenarios and then estimates the aggregate manpower, materials, and capital requirements needed to develop the energy system described by the particular scenario. The total requirements and the energy subsystems for each scenario are assessed for their primary impacts in the areas of society, the environment, technology and the economy.

Source record↗
NASA NTRS1972

Timing requirements for the Sanguine ELF communications system

The development of an extremely low frequency (ELF) communications system for command and control of naval forces is discussed. The basic requirements for the system are defined. Emphasis is placed on the clock requirements based on phase or time rather than frequency. The time and frequency requirements at the transmitter stations are tabulated.

Kruger, B.↗
NASA NTRS1974

An assessment of the Instrument Pointing Subsystems (IPS) requirements for spacelab missions

Instrument Pointing Subsystem requirements for Spacelab missions in solar physics, stellar astronomy, and earth observation are analyzed and design guidelines for fine pointing instrument platforms are presented. The requirements for the platforms are time-phased based on NASA projections of flight mission models and payload scheduling. The experiments used for these projections are to be viewed as representative payloads. Other experiments or experiment groupings within any one discipline may be accommodated by an Instrument Pointing Subsystem that meets these requirements.

Nein, M. E.↗
NASA NTRS1974

Frequency standards requirements of the NASA deep space network to support outer planet missions

Navigation of Mariner spacecraft to Jupiter and beyond will require greater accuracy of positional determination than heretofore obtained if the full experimental capabilities of this type of spacecraft are to be utilized. Advanced navigational techniques which will be available by 1977 include Very Long Baseline Interferometry (VLBI), three-way Doppler tracking (sometimes called quasi-VLBI), and two-way Doppler tracking. It is shown that VLBI and quasi-VLBI methods depend on the same basic concept, and that they impose nearly the same requirements on the stability of frequency standards at the tracking stations. It is also shown how a realistic modelling of spacecraft navigational errors prevents overspecifying the requirements to frequency stability.

Fliegel, H. F.↗
NASA NTRS1974

TERSSE: Definition of the Total Earth Resources System for the Shuttle Era. Volume 8: User's Mission and System Requirements Data (appendix A of Volume 3)

A computer printout is presented of the mission requirement for the TERSSE missions and their associated user tasks. The data included in the data base represents a broad-based attempt to define the amount, extent, and type of information needed for an earth resources management program in the era of the space shuttle. An effort was made to consider all aspects of remote sensing and resource management; because of its broad scope, it is not intended that the data be used without verification for in-depth studies of particular missions and/or users. The data base represents the quantitative structure necessary to define the TERSSE architecture and requirements, and to an overall integrated view of the earth resources technology requirements of the 1980's.

Source record↗
NASA NTRS1975

Integration time required to extract accurate static and dynamic data from transonic wind-tunnel tests

Because the forces and pressures on wind-tunnel models tested at transonic speeds are not steady, even for 'static' aerodynamic tests, integration time is required to obtain data of acceptable accuracy. The integration time required for both static and dynamic tests is evaluated analytically and confirmed by experimental measurements. It is shown that, for static and dynamic tests, the accuracy obtained is a function of integration time, frequency content of the signal, and the ratio of the dynamic amplitude to the full signal of interest. In addition, for the dynamic case, the frequency band width used in analysis is important. Results of this study indicate that, for typical data accuracy desired from models in a large transonic wind tunnel (11- by 11-ft), up to the following integration times are required: static force and moment tests, 0.5 sec; static pressure tests, 0.1 sec; flutter tests, 30 to 60 sec; and random-dynamic tests, 10 sec.

Muhlstein, L., Jr.↗
NASA NTRS1975

Manned orbital systems concepts study. Book 2: Requirements for extended-duration missions

In order to provide essential data needed in long-range program planning, the Manned Orbital Systems Concepts (MOSC) study attempted to define, evaluate, and compare concepts for manned orbital systems that provide extended experiment mission capabilities in space, flexibility of operation, and growth potential. Specific areas discussed include roles and requirements for man in future space missions, requirements for extended capability, mission/payload concepts, and preliminary design and operational requirements.

Source record↗
NASA NTRS1975

Tug and payload-to-Orbiter interface requirements

This paper presents results of a study to identify, evaluate, and develop Tug plus payload-to-Orbiter accommodation requirements. Interface areas include structural, mechanical, fluids, environmental, avionics, and safety. Each interface area was investigated to determine the best physical and operational method of accomplishing the required functions with an overriding goal of establishing sample and flexible interface requirements suitable for Tug, Tug payloads, and other cargo. The recommended system for supporting the Tug and its payload from the Orbiter employs a cylindrical load-carrying structure called a deployment adapter that has a rotational capability for Tug deployment. The design and operation of the deployment adapter and other peripheral interface equipment such as crew compartment monitor and control panels and cargo bay fluid and electrical interface panels are discussed.

Bock, E. H.↗
NASA NTRS1975

Image recording requirements for earth observation applications in the next decade

Future requirements for satellite-borne image recording systems are examined from the standpoints of system performance, system operation, product type, and product quality. Emphasis is on total system design while keeping in mind that the image recorder or scanner is the most crucial element which will affect the end product quality more than any other element within the system. Consideration of total system design and implementation for sustained operational usage must encompass the requirements for flexibility of input data and recording speed, pixel density, aspect ratio, and format size. To produce this type of system requires solution of challenging problems in interfacing the data source with the recorder, maintaining synchronization between the data source and the recorder, and maintaining a consistent level of quality. Film products of better quality than is currently achieved in a routine manner are needed. A 0.1 pixel geometric accuracy and 0.0001 d.u. radiometric accuracy on standard (240 mm) size format should be accepted as a goal to be reached in the near future.

Peavey, B.↗
NASA NTRS1977

Space station systems analysis study. Part 2, Volume 3: Appendixes, Book 1. Program requirements documentation

The objective elements representative of the kinds of space activities that will be supported by the space construction base (SCB) are discussed in (1) a brief mission overview including the primary purpose and general objectives; (2) descriptions of the processes involved (where applicable), the mission hardware, the principal activities to be undertaken, the test requirements, and the principal tests; and (3) the SCB requirements including such items as special devices (e.g., fabrication modules, assembly or construction fixtures, cranes, and airlocks), power, data management and communications, waste management, environmental control, safety, and logistics. Each program option is then described in terms of the objective elements it supports, its orbit, the general makeup of the SCB, the transportation approach, and the program schedule goals. The specific requirements that are imposed on the SCB in order to support program option L are given.

Source record↗
NASA NTRS1977

Public Service Communications Satellite User Requirements Workshop

Information on user requirements for public service communications was acquired to provide the basis of a study to determine the optimum satellite system to satisfy user requirements. The concept for such a system is described: Topics discussed included requirements for data and message services, elementary and secondary education, extension and continuing education, environmental communications, library services, medical education, medical services, public broadcasting, public safety, religious applications, state and local communications, and voluntary services. Information was also obtained on procedures to follow to make the transfer to commercial services.

Wolff, E. A.↗