December 1999

Briefs : Electronics & Computers
Optically Transparent Patch Antennas

Optically transparent patch antennas have been invented for use in communication systems at frequencies of the order of a few gigahertz. These antennas can be mounted on windows of buildings and vehicles, on computer video monitors, on solar photovoltaic panels, and on other convenient supports; this is an...

Briefs : Electronics & Computers
Improved Thermoelectric Converter Units and Power Generators

Improved thermoelectric converter units (TCUs) and radioisotope thermoelectric generators (RTGs) that contain them have been undergoing development for use as small, lightweight sources of electricity at potentials up to 5 V and power at levels up to 40 mW. These RTGs are intended...

Briefs : Motion Control
Axial Force as Indication of Alignment of Threaded Fasteners

A developmental technique for automated alignment of threaded fasteners involves the use of the axial force between the fasteners as an indication of alignment. The technique was conceived as a means to guide a robot that is required, for example, to join a bolt with a nut.

Briefs : Materials
Organic/Inorganic Coats for Packaging of Microelectronics

A method for protective packaging of multichip modules and related assemblies of microelectronic circuitry involves coating the assemblies with composite organic/inorganic layers only 1 to 2 mils (0.025 to 0.05 mm) thick. The method is suitable for a variety of advanced packages of...

Briefs : Electronics & Computers
Quick Guide to MSAT

A report presents additional information on the Mechanical System Design/Analysis Tool (MSAT) computer program, which was reported in "Program for Designing a Mechanical System" (LEW-16710, NASA Tech Briefs, Vol. 23, No. 9 (September 1999), page 32. To recapitulate: MSAT is a user-friendly, multidisciplinary software system...

Briefs : Physical Sciences
Updates on Optical Diagnosis of Fuel Spray Patterns

A collection of three reports presents an expanded discussion of the topic of "Optical Diagnostics of High-Pressure Liquid Fuel Sprays" (LEW-16701),NASA Tech Briefs, Vol. 23, No. 3 (March 1999), page 18a. The reports describe experiments in which fuel sprays representative of those in...

Briefs : Mechanical & Fluid Systems
Boundary-Layer Rake of Pitot Tubes for Flight Testing

A boundary-layer rake of pitot tubes has been designed and built for installation on a flight-test fixture (FTF) on the NASA Dryden F-15B, which is a two-seat version of the F-15 high-performance, supersonic, all-weather fighter airplane. This boundary-layer rake will be used in...

Briefs : Motion Control
Small-Stroke, High-Frequency Reciprocating Pump

A proposed reciprocating pump would operate at a small stroke and would contain no sliding parts. The oscillatory motion of a piston in the pump could be provided by a magnetostrictive actuator, for example.

Briefs : Physical Sciences
Time-Parallel Solutions of Linear PDEs on a Supercomputer

A paper describes the mathematical basis and some applications of a class of massively parallel algorithms for finite-difference numerical solution of some time-dependent partial differential equations (PDEs) on massively parallel supercomputers. In a radical departure from the...

Briefs : Software
Software for Setting Up Equipment for Testing Rocket Engines

A computer program has been developed to shorten the time needed to set up electronic instrumentation for a hot-fire test of a rocket engine. The instrumentation in question is a modular, partly computer-controlled apparatus, the modules of which contain amplifiers and other...

Briefs : Electronics & Computers
Array Detector for Charge-Detection Mass Spectrometer

The pixelated array detector (PAD) is a planar array of complementary metal oxide/semiconductor (CMOS) charge-collecting electrodes and readout circuitry for measuring the electric charges on particles in a charge-detection mass spectrometer (CDMS). In comparison with a single-Faraday-cup...

Briefs : Physical Sciences
Forward-Scattering Particle-Image Velocimetry

Forward-scattering particle-image velocimetry (FSPIV) is a technique for measuring velocities in microscopic flow fields as thin liquid films. As in other particle-image-velocimetry (PIV) techniques, the velocity of a flow is computed from temporally changing images of suitably illuminated,...

Briefs : Electronics & Computers
High-Power-Density DC-to-DC Power-Converter Modules

Dc-to-dc power-converter modules that operate with input potentials from 60 to 140 V and generate various output potentials up to 15 V are undergoing development. Designed specifically for use aboard planned spacecraft wherein electric power will be supplied at bus potentials from 70 to 120 V,...

Briefs : Physical Sciences
Imaging System With TDI and a Two-Axis-Scanning Mirror

A telescopic imaging system that includes an optomechanical scanning subsystem is undergoing development. The system is designed for use in scientific observation of the Earth from aboard a satellite in geostationary orbit. The basic principles of the optomechanical scanning subsystem may...

Briefs : Electronics & Computers
M-JPEG Video Compression System for Space-Based Applications

An M-JPEG video compression system has been modified to satisfy the unique requirements of space-based applications. ["M-JPEG" signifies the still-image-data-compression method of the Joint Photographic Experts Group (JPEG) as applied to moving (e.g., video) images.] This ruggedly...

Briefs : Information Technology
NSUTCQ: an Alternative Image-Compression Algorithm

No-shift universal trellis-coded quantization (NSUTCQ) is an image-data-compression/decompression algorithm designed to be especially useful in telemedicine. Like some other image-compression/decompression algorithms, this one provides both (1) lossy compression/decompression for transmission...

Briefs : Electronics & Computers
Acousto-Optic Tunable Filter Spectrometers

Spectrometers are used for applications such as chemical analysis, remote sensing, environmental measuring, and optical measurements. Most spectrometers utilize prisms and gratings, where the dispersion of light depends upon the angle and rotation of the grating. But gratings and other moving parts are...

Briefs : Physical Sciences
Low-Absorption Color Filters for Flat-Panel Display Devices

A proposed technique for color filtering in a liquid-crystal or other flat-panel display device would make it possible to brighten the display without increasing the amount of light supplied from behind the panel. The need for the proposed technique arises as follows: At present, each...

Briefs : Motion Control
Heat-Driven Pulse Pump

The heat-driven pulse pump has been invented in an effort to satisfy a need for pumps that can circulate heat-transfer fluids at low flow rates with high reliability over long operational lifetimes. The heat-driven pulse pump (HDPP) is so named because it generates pumping action by exploiting periodic (pulsed) heating...

Briefs : Information Technology
Software for Scanning, Storing, and Retrieving Images

An application program for scanning and storage of images and for retrieval of the images via the World Wide Web has been written in the Java programming language to be portable to any computer and operating system that support the Java Virtual Machine 1.02. The program can be run on one...

Briefs : Motion Control
Improved Magnetostrictive Pump

An improved magnetostrictively actuated pump has been developed to satisfy a need for a small, low-pressure, high-flow-rate fluid pump that contains few moving parts and can run reliably for long periods without maintenance. The pump could be used, for example, to circulate water in the portable life-support...

Briefs : Electronics & Computers
Wireless Information Network

A wireless information network (WIN) is undergoing development for use by workers at locations scattered across Kennedy Space Center (KSC). This WIN could be a prototype of a larger network that would serve all of NASA; by logical extension, it could also be a prototype of commercial WINs. By use of a combination of...

Briefs : Materials
Sputter Deposition of Catalysts for Fuel-Cell Electrodes

An improved method of fabricating electrodes for fuel cells includes the use of sputtering to deposit thin layers of catalytic electrode metals. Previously, catalytic electrode metals were deposited by means of inks and decals - means that are not amenable to mass production. The...

Motion Control Technology : Robotics, Automation & Control
Alternative One-Time-Opening Miniature Isolation Valve

The figure depicts a proposed miniature, electrically actuated, one-time-opening isolation valve that would be made mostly of silicon, by use of micromachining techniques. Isolation valves are needed in systems in which fluids must be stored for long times until use, with no leakage or...

Briefs : Software
Software for Environmental Monitoring in a Large Facility

Four computer programs enable the nearly real-time distribution, analysis, and display of data on temperature, relative humidity, and particle fallout measured by sensors in the Orbiter Processing Facility (OPF) and the Launch Pad Payload Changeout Room (PCR) at Kennedy Space Center. The...

Briefs : Electronics & Computers
Circuit Detects Pyrolysis of Polyimide Insulation on Wires

An electronic circuit has been designed as a prototype of a device that determines whether critical electrical systems have been compromised because of pyrolysis of polyimide-insulated wires. This circuit can be modified to prevent further pyrolysis and to check for indications of...

Technology Leaders