Search NASA⌕ Search

SEARCH · Search NASA

Results for “Design and Construction”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,585 records · Page 88

Controlling and monitoring the space-station plasma interaction: A baseline for performing plasma experiments and using advanced technology

The size, complexity, and motion of space station through the Earth's environmental plasma means that there will be a large, complicated interaction region, involving a sheath, wake, charging of surfaces, induced electric fields, secondary emission, outgassing with ionization, etc. This interaction will necessarily be a factor in carrying out and interpreting plasma experiments and in the use of certain technologies. Attention should be given ahead of time to: (1) monitoring this interaction so that it is well described; (2) implifying the interaction by appropriate design and construction of the spacecraft and by appropriate planning of technology use; and (3) controlling the interaction by both active and passive means. Plasma emitters for modifying and controlling the spacecraft charge should be placed in several locations. Portable electrostatic shields could be deployed around noisy sections of the spacecraft in order to carry out sensitive experiments. A particle umbrella could be raised to deflect the ram ions and neutrals in order to provide a controlled environment. These interactions are briefly discussed.

Whipple, Elden C.↗

Aerodynamic measurements and thermal tests of a strain-gage balance in a cryogenic wind tunnel

An internal strain-gage balance designed and constructed in Europe for use in cryogenic wind tunnels has been tested in the Langley 0.3-Meter Transonic Cryogenic Tunnel. Part of the evaluation was made at equilibrium balance temperatures and it consisted of comparing the data taken at a tunnel stagnation temperature of 300 K with the data taken at 200 K and 110 K while maintaining either the Reynolds number or the stagnation pressure. A sharp-leading-edge delta-wing model was used to provide the aerodynamic loading for these tests. Results obtained with the balance during the force tests were found to be accurate and repeatable both with and without the use of a convection shield on the balance. An additional part of this investigation involved obtaining data on the transient temperature response of the balance during both normal and rapid changes in the tunnel stagnation temperature. The variation of the temperature with time was measured at three locations on the balance near the physical locations of the strain gages. The use of a convection shield significantly increased the time required for the balance to stabilize at a new temperature during the temperature response tests.

Boyden, Richmond P.↗

Documentation of the space station/aircraft acoustic apparatus

This paper documents the design and construction of the Space Station/Aircraft Acoustic Apparatus (SS/AAA). Its capabilities both as a space station acoustic simulator and as an aircraft acoustic simulator are described. Also indicated are the considerations which ultimately resulted in man-rating the SS/AAA. In addition, the results of noise surveys and reverberation time and absorption coefficient measurements are included.

Clevenson, Sherman A.↗

Aluminum-oxygen batteries for space applications

An aluminum oxygen fuel cell is under development. Several highly efficient cell designs were constructed and tested. Air cathodes catalyzed with cobalt tetramethoxy porphorin have demonstrated more than 2000 cycles in intermittant use conditions. Aluminum alloys have operated at 4.2 kWH/kg at 200 mA/sq cm. A novel separator device, an impeller fluidizer was coupled with the battery to remove the solid hydrargillite discharge product. A 60 kW, 720 kWH battery system is projected to weigh about 2200 lbs., for an energy density of 327 WH lb.

Niksa, Marilyn J.↗

Particle cloud kinetics in microgravity

Data related to particle-particle agglomeration/deaglomeration and particle-wall attachment are discussed. Particle-cluster cloud interactions and particle-cluster agglomeration/deagglomeration kinetics are studied. An apparatus designed and constructed for examining the agglomeration/deagglomeration effects for lycopodium under the conditions of an acoustically energized mixing process and of alpha-particle-induced deagglomerative processes is described; characteristic features and applications for the apparatus are examined. Requirements for combustion experimentation are discussed.

Berlad, A. L.↗

Efficient He-4 cryostats for storage Dewars

He-4 cryostats which can be inserted into storage Dewars were designed. These cryostats have the advantages of extremely low (and recoverable) helium consumption, fast cool-down and warm-up times, excellent temperature range and stability, and they supply a low electrical noise and low vibration environment for electrical and thermal measurements. Design and construction details of one such cryostat are presented. Specific heat data on crystalline boron are also presented to demonstrate the performance of one of these cryostats in a particularly sensitive experiment.

Swartz, E. T.↗

A program to study antiprotons in the cosmic rays: Arizona collaboration

The Low Energy AntiProton (LEAP) experiment was designed to measure the primary antiproton flux in the 200 MeV to 1 GeV kinetic energy range. A superconducting magnetic spectrometer, a time-of-flight (TOF) detector, and a Cherenkov counter are the main components of LEAP. An additional scintillation detector was designed and constructed to detect the passage of particles through the bottom of the Cherenkov counter. The LEAP package was launched on August 22, 1987, and enjoyed a 27 hour flight, with 23 hours of data at high altitude. Preliminary plans for data analysis include using the Micro-Vax at the University of Arizona for data reduction of the Cherenkov and S2 signals.

Bowen, Theodore↗

MTK: An AI tool for model-based reasoning

A 1988 goal for the Systems Autonomy Demonstration Project Office of the NASA Ames Research Center is to apply model-based representation and reasoning techniques in a knowledge-based system that will provide monitoring, fault diagnosis, control and trend analysis of the space station Thermal Management System (TMS). A number of issues raised during the development of the first prototype system inspired the design and construction of a model-based reasoning tool called MTK, which was used in the building of the second prototype. These issues are outlined, along with examples from the thermal system to highlight the motivating factors behind them. An overview of the capabilities of MTK is given.

Erickson, William K.↗

MTK: An AI tool for model-based reasoning

A 1988 goal for the Systems Autonomy Demonstration Project Office of the NASA Ames Research Office is to apply model-based representation and reasoning techniques in a knowledge-based system that will provide monitoring, fault diagnosis, control, and trend analysis of the Space Station Thermal Control System (TCS). A number of issues raised during the development of the first prototype system inspired the design and construction of a model-based reasoning tool called MTK, which was used in the building of the second prototype. These issues are outlined here with examples from the thermal system to highlight the motivating factors behind them, followed by an overview of the capabilities of MTK, which was developed to address these issues in a generic fashion.

Erickson, William K.↗

Automation software for a materials testing laboratory

A comprehensive software system for automating much of the experimental process has recently been completed at the Lewis Research Center's high-temperature fatigue and structures laboratory. The system was designed to support experiment definition and conduct, results analysis and archiving, and report generation activities. This was accomplished through the design and construction of several software systems, as well as through the use of several commercially available software products, all operating on a local, distributed minicomputer system. Experimental capabilities currently supported in an automated fashion include both isothermal and thermomechanical fatigue and deformation testing capabilities. The future growth and expansion of this system will be directed toward providing multiaxial test control, enhanced thermomechanical test control, and higher test frequency (hundreds of hertz).

Mcgaw, Michael A.↗

Dielectrophoresis in the microgravity environment

Microgravity and vacuum, singly or combined, are uniquely advantageous media for the use of dielectrophoresis as a mmaterial s separation technology. In order to assess these advantages, a free-fall vacuum dielectrophoretic separator was designed and constructed for use at the earth's surface.

Rose, R. M.↗

The 13-inch magnetic suspension and balance system wind tunnel

NASA Langley has a small, subsonic wind tunnel in use with the 13-inch Magnetic Suspension and Balance System (MSBS). The tunnel is capable of speeds up to Mach 0.5. This report presents tunnel design and construction details. It includes flow uniformity, angularity, and velocity fluctuation data. It also compares experimental Mach number distribution data with computed results for the General Electric Streamtube Curvature Program.

Johnson, William G., Jr.↗

Static tensile and tensile creep testing of five ceramic fibers at elevated temperatures

Static tensile and tensile creep testing of five ceramic fibers at elevated temperature was performed. J.P. Stevens, Co., Astroquartz 9288 glass fiber, Nippon Carbon, Ltd., (Dow Corning) Nicalon NLM-102 silicon carbide fiber, and 3M Company Nextel 312, 380, and 480 alumina/silica/boria fibers were supplied in unsized tows. Single fibers were separated from the tows and tested in static tension and tensile creep. Elevated test temperatures ranged from 400 to 1300 C and varied for each fiber. Room temperature static tension was also performed. Computer software was written to reduce all single fiber test data into engineering constants using ASTM Standard Test Method D3379-75 as a reference. A high temperature furnace was designed and built to perform the single fiber elevated temperature testing up to 1300 C. A computerized single fiber creep apparatus was designed and constructed to perform four fiber creep tests simultaneously at temperatures up to 1300 C. Computer software was written to acquire and reduce all creep data.

Zimmerman, Richard S.↗

Static tensile and tensile creep testing of five ceramic fibers at elevated temperatures

Static tensile and tensile creep testing of five ceramic fibers at elevated temperature was performed. J.P. Stevens, Co., Astroquartz 9288 glass fiber; Nippon Carbon, Ltd., (Dow Corning) nicalon NLM-102 silicon carbide fiber; and 3M Company Nextel 312, 380, and 480 alumina/silica/boria fibers were supplied in unsized tows. Single fibers were separated from the tows and tested in static tension and tensile creep. Elevated test temperatures ranged from 400 C to 1300 C and varied for each fiber. Room temperature static tension was also performed. Computer software was written to reduce all single fiber test data into engineering constants using ASTM Standard Test Method D3379-75 as a reference. A high temperature furnace was designed and built to perform the single fiber elevated temperature testing up to 1300 C. A computerized single fiber creep apparatus was designed and constructed to perform four fiber creep tests simultaneously at temperatures up to 1300 C. Computer software was written to acquire and reduce all creep data.

Zimmerman, Richard S.↗

Common Graphics Library (CGL). Volume 2: Low-level user's guide

The intent is to instruct the users of the Low-Level routines of the Common Graphics Library (CGL). The Low-Level routines form an application-independent graphics package enabling the user community to construct and design scientific charts conforming to the publication and/or viewgraph process. The Low-Level routines allow the user to design unique or unusual report-quality charts from a set of graphics utilities. The features of these routines can be used stand-alone or in conjunction with other packages to enhance or augment their capabilities. This library is written in ANSI FORTRAN 77, and currently uses a CORE-based underlying graphics package, and is therefore machine-independent, providing support for centralized and/or distributed computer systems.

Taylor, Nancy L.↗

Monitoring robot actions for error detection and recovery

Reliability is a serious problem in computer controlled robot systems. Although robots serve successfully in relatively simple applications such as painting and spot welding, their potential in areas such as automated assembly is hampered by programming problems. A program for assembling parts may be logically correct, execute correctly on a simulator, and even execute correctly on a robot most of the time, yet still fail unexpectedly in the face of real world uncertainties. Recovery from such errors is far more complicated than recovery from simple controller errors, since even expected errors can often manifest themselves in unexpected ways. Here, a novel approach is presented for improving robot reliability. Instead of anticipating errors, researchers use knowledge-based programming techniques so that the robot can autonomously exploit knowledge about its task and environment to detect and recover from failures. They describe preliminary experiment of a system that they designed and constructed.

Gini, M.↗

Rapidly solidified titanium alloys by melt overflow

A pilot plant scale furnace was designed and constructed for casting titanium alloy strips. The furnace combines plasma arc skull melting techniques with melt overflow rapid solidification technology. A mathematical model of the melting and casting process was developed. The furnace cast strip of a suitable length and width for use with honeycomb structures. Titanium alloys Ti-6Al-4V and Ti-14Al-21 Nb were successfully cast into strips. The strips were evaluated by optical metallography, microhardness measurements, chemical analysis, and cold rolling.

Gaspar, Thomas A.↗

Large aperture scanning airborne lidar

A large aperture scanning airborne lidar facility is being developed to provide important new capabilities for airborne lidar sensor systems. The proposed scanning mechanism allows for a large aperture telescope (25 in. diameter) in front of an elliptical flat (25 x 36 in.) turning mirror positioned at a 45 degree angle with respect to the telescope optical axis. The lidar scanning capability will provide opportunities for acquiring new data sets for atmospheric, earth resources, and oceans communities. This completed facility will also make available the opportunity to acquire simulated EOS lidar data on a near global basis. The design and construction of this unique scanning mechanism presents exciting technological challenges of maintaining the turning mirror optical flatness during scanning while exposed to extreme temperatures, ambient pressures, aircraft vibrations, etc.

Smith, J.↗