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Results for “evaluation of test systems”

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 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1981

Earth orbital teleoperator system evaluation: Test report, 1979 - 1980

Areas which have significant influence upon the engineering design of an operational teleoperator are addressed. Teleoperator lighting systems, thruster systems, and stereoptic visual systems are discussed. The effects of specified levels of several teleoperator subsystems on human operator performance are determined. Four evaluations are reviewed, each dealing with operator performance under various task conditions.

Source record↗
NASA NTRS1973

Reusable surface insulation thermal protection systems test evaluation status

Changes in coating morphology of mullite, silica, and ceramic mullite fiber at two heating rates are described followed by a discussion of the changes in surface chemistry that occur during convective heating tests. Subsequently, the surface chemistry changes observed are compared to similar data obtained from radiantly heated coatings and the significance of the difference between the results is discussed. Finally, the changes in chemistry of the coatings in cross section before and after convectively heated cyclic testing are discussed and the significance of surface chemistry changes are described. Results indicate that the thermal conductivity of mullite surface insulation is higher than that of silica insulation, based on thermal response data. Acoustic excitation of cracked silica tiles does not lead to catastrophic failure such as spallation or tile loss. Cracks in mullite material after thermal exposure lead to fracturing of the coating and surface insulation material after acoustic excitation.

Strouhal, G.↗
NASA NTRS1981

The DOE ETV-1 Electric Test Vehicle. Phase 3: Performance Testing and system evaluation

Engineering tests were conducted in order to characterize overall system performance and component efficiencies within the system environment. A dynamometer was used in order to minimize the ambient effects and large uncertainties present in track testing. Extensive test requirements were defined and procedures were carefully controlled in order to maintain a high degree of credibility. Limited track testing was performed in order to corroborate the dynamometer results. Test results include an energy flow analysis through the major subsystems and incorporate the aerodynamic and rolling losses under cyclic and various steady speed conditions. The major output from all relevant dynamometer and track tests is also included.

Kurtz, D.↗
NASA NTRS1977

Shuttle communication systems compatibility and performance testing

The Shuttle communications system consists of major space and ground elements. The compatibility and performance of each of these major elements functioning as a complete system must be certified prior to operational missions. This paper discusses the Shuttle communication systems compatibility and performance testing. The system test philosophy for the complex communication channels is described in terms of the major phases, which include early breadboard system design evaluation tests, system development tests with prototype hardware, and system certification testing with qualifiable (flight) hardware. The system hardware configuration, facility requirements, test and evaluation techniques, and operational approaches required to accomplish each major phase of testing are reviewed. Results of recently completed space-to-space and space-to-ground system tests are presented. Test techniques and measurement accuracies proven over ten years of unique system-evaluation experience are reviewed. Techniques used in relating experimental and predicted system performance, and conclusions regarding the effectiveness of system level testing of such complex hardware, are addressed.

Seyl, J. W.↗
NASA NTRS1975

Pseudo-noise test set for communication system evaluation

A test set for communications systems is described which includes a pseudo noise sequence generator providing a test signal that is fed to a pair of signal channels. The first channel includes a spectrum shaping filter and a conditioning amplifier. The second channel includes a variable delay circuit, a spectrum shaping filter matched to the first filter, and an amplifier. The output of the first channel was applied to the system under test. The output of the system and the output of the second channel are compared to determine the degree of distortion suffered by the test signal due to the communications system.

Wallace, G. R.↗
NASA NTRS2001

Development of a Low-Cost, Subscale Test System to Evaluate Particle Impingement Erosion in Nozzle Ablative Materials

This viewgraph presentation gives an overview on the development of a low-cost, subscale test system to evaluate particle impingement erosion in nozzle ablative materials. Details are given on the need for a new test bed, solid fuel torch components, solid fuel torch test, additional uses for the solid fuel torch, the development of a supersonic blast tube (SSBT), and particle impingement material discrimination.

Lansing, Matthew D.↗
NASA NTRSDate not supplied

Ground-based Design of a Test System to Evaluate Static Vapor Feed Electrolysis for Oxygen Generation

NASA designed a test facility to evaluate the performance of a Static Vapor Feed Electrolysis (SVFE) cell stack to determine its viability as an alternative technology to the state-of-the-art Oxygen Generation Assembly (OGA) to generate oxygen for habitable spacecraft environments. Static Vapor Feed Electrolysis differs from the liquid cathode-feed process utilized by the OGA in that the electrolysis process occurs entirely in the gas phase, operates at a higher pressure than OGA, and potentially requires a simpler balance-of-plant system. Pressurized liquid water is statically-fed, i.e. dead-headed, through a vapor-permeable membrane into the electrolysis chamber of the cell stack. The water vapor is then electrolyzed into hydrogen and oxygen in the cathode and anode chambers, respectively, all the while maintaining above-ambient pressures to eliminate water condensation in the oxygen and hydrogen product streams. This paper presents the design of the test facility and accompanying required balance-of-plant that will be used to test the SVFE cell stack.

Zeeshan Khawar↗
NASA NTRS2014

Visual Advantage of Enhanced Flight Vision System During NextGen Flight Test Evaluation

Synthetic Vision Systems and Enhanced Flight Vision System (SVS/EFVS) technologies have the potential to provide additional margins of safety for aircrew performance and enable operational improvements for low visibility operations in the terminal area environment. Simulation and flight tests were jointly sponsored by NASA's Aviation Safety Program, Vehicle Systems Safety Technology project and the Federal Aviation Administration (FAA) to evaluate potential safety and operational benefits of SVS/EFVS technologies in low visibility Next Generation Air Transportation System (NextGen) operations. The flight tests were conducted by a team of Honeywell, Gulfstream Aerospace Corporation and NASA personnel with the goal of obtaining pilot-in-the-loop test data for flight validation, verification, and demonstration of selected SVS/EFVS operational and system-level performance capabilities. Nine test flights were flown in Gulfstream's G450 flight test aircraft outfitted with the SVS/EFVS technologies under low visibility instrument meteorological conditions. Evaluation pilots flew 108 approaches in low visibility weather conditions (600 feet to 3600 feet reported visibility) under different obscurants (mist, fog, drizzle fog, frozen fog) and sky cover (broken, overcast). Flight test videos were evaluated at three different altitudes (decision altitude, 100 feet radar altitude, and touchdown) to determine the visual advantage afforded to the pilot using the EFVS/Forward-Looking InfraRed (FLIR) imagery compared to natural vision. Results indicate the EFVS provided a visual advantage of two to three times over that of the out-the-window (OTW) view. The EFVS allowed pilots to view the runway environment, specifically runway lights, before they would be able to OTW with natural vision.

Kramer, Lynda J.↗
NASA NTRS1981

Automated pilot advisory system test and evaluation at Manassas Municipal Airport

In cooperation with the Federal Aviation Administration, NASA developed an experimental automated pilot advisory system (APAS) to provide airport and air traffic advisories at high density uncontrolled airports. The APAS concept is to utilize low cost automated systems to provide the necessary information for pilots to more safely plan and execute approach and landing at uncontrolled high density airports. The system is designed to be a natural extension of the procedural visual flight rules system used at uncontrolled airports and, as an advisory system, will enhance the "see-and-be-seen" rule and an evaluation of the APAS concept was obtained from pilots who used the system at the Manassas, Virginia airport. These evaluations and the system performance are presented.

Parks, J. L., Jr.↗
NASA NTRS1978

SEC sensor parametric test and evaluation system

This system provides the necessary automated hardware required to carry out, in conjunction with the existing 70 mm SEC television camera, the sensor evaluation tests which are described in detail. The Parametric Test Set (PTS) was completed and is used in a semiautomatic data acquisition and control mode to test the development of the 70 mm SEC sensor, WX 32193. Data analysis of raw data is performed on the Princeton IBM 360-91 computer.

Source record↗
NASA NTRS1986

Surveillance systems test and evaluation facilities

In January of 1983, a team was formed to explore test methodologies and test facility concepts required to meet the needs of space-based surveillance systems. The output of this study was a road map of test methodologies and test facilities that will aid the development of this country's critical space-based sensor assets. A condensation of those results is given.

Matty, Jere J.↗
NASA NTRS1980

Shuttle orbiter Ku-band radar/communications system design evaluation

Tasks performed in an examination and critique of a Ku-band radar communications system for the shuttle orbiter are reported. Topics cover: (1) Ku-band high gain antenna/widebeam horn design evaluation; (2) evaluation of the Ku-band SPA and EA-1 LRU software; (3) system test evaluation; (4) critical design review and development test evaluation; (5) Ku-band bent pipe channel performance evaluation; (6) Ku-band LRU interchangeability analysis; and (7) deliverable test equipment evaluation. Where discrepancies were found, modifications and improvements to the Ku-band system and the associated test procedures are suggested.

Dodds, J.↗
NASA NTRS1980

Shuttle orbiter Ku-band radar/communications system design evaluation. Deliverable test equipment evaluation

The Ku-band test equipment, known as the Deliverable System Test equipment (DSTE), is reviewed and evaluated. The DSTE is semiautomated and computer programs were generated for 14 communication mode tests and 17 radar mode tests. The 31 test modules provide a good cross section of tests with which to exercise the Ku-band system; however, it is very limited when being used to verify Ku-band system performance. More detailed test descriptions are needed, and a major area of concern is the DSTE sell-off procedure which is inadequate.

Maronde, R. G.↗
NASA NTRS1974

Path selection system development and evaluation for a Martian roving vehicle

A path selection system evaluation test procedure has been developed to enhance the analysis capability of an existing digital computer simulation package. The procedure investigates the obstacle avoidance ability of a path selection system on a sequence of test terrains with and without random effects. Using the standard test procedure a proposed mid-range sensor system has been evaluated and recommendations directed at improving the performance of the system have been made. In addition, the initial development and evaluation of a short range sensor system has been undertaken.

Campbell, R. S.↗
NASA NTRS1976

Development of thermal control methods for specialized components and scientific instruments at very low temperatures (follow-on)

Many payloads currently proposed to be flown by the space shuttle system require long-duration cooling in the 3 to 200 K temperature range. Common requirements also exist for certain DOD payloads. Parametric design and optimization studies are reported for multistage and diode heat pipe radiator systems designed to operate in this temperature range. Also optimized are ground test systems for two long-life passive thermal control concepts operating under specified space environmental conditions. The ground test systems evaluated are ultimately intended to evolve into flight test qualification prototypes for early shuttle flights.

Wright, J. P.↗
NASA NTRS2014

NEPP DDR Device Reliability FY13 Report

This document reports the status of the NEPP Double Data Rate (DDR) Device Reliability effort for FY2013. The task targeted general reliability of > 100 DDR2 devices from Hynix, Samsung, and Micron. Detailed characterization of some devices when stressed by several data storage patterns was studied, targeting ability of the data cells to store the different data patterns without refresh, highlighting the weakest bits. DDR2, Reliability, Data Retention, Temperature Stress, Test System Evaluation, General Reliability, IDD measurements, electronic parts, parts testing, microcircuits

Guertin, Steven M.↗
NASA NTRS1990

A simulation-based test bed for data-association algorithms

A modular All-Source System-evaluation Test bed (ASSET) designed and developed for aiding in the testing and evaluation of advanced data-acquisition algorithms is described, with focus placed on the problem of integrating surveillance information in supporting command decision making. The evaluation procedure employed is based on a measure of the distance between a baseline representation and the representation produced by the association algorithm at some time instant. Choices for the baseline representation are presented, and scores are defined between these baselines and an algorithm representation. The test-bed architecture implementing the evaluation procedure is described, and sample outputs from performing algorithm evaluations in the test bed are outlined.

Brown, Donald E.↗