June 1999

Briefs : Mechanical & Fluid Systems
Improved Inlets for T-38 Airplane

A change in the design of the engine inlets of the T-38 airplane significantly reduces takeoff distances while increasing safety margins. Although the newer inlet design (see Figure 1) is based on well-known engineering principles, it is unique and will prove invaluable to the NASA fleet and to other T-38...

Briefs : Mechanical & Fluid Systems
Smoother Wing Leading-Edge Joints Would Favor Laminar Flow

Some changes in the design and construction of the leading edges of metal airplane wings have shown promise as means to suppress laminar-to-turbulent flow transitions. The significance of this development is that it creates an opportunity to take advantage of laminar-flow boundary...

Briefs : Physical Sciences
Kit for Sampling Nitrosamines From Aqueous Solutions

Scientists at White Sands Test Facility (WSTF) have devised a kit for extracting nitrosamines from aqueous solutions. In comparison with extractions according to the method recommended by the Environmental Protection Agency (EPA), extractions by use of the kit are faster, cheaper and less...

Briefs : Motion Control
Linear Motors Offer New Motion Capabilities

The linear motor was invented in the mid-nineteenth century, at much the same time as its brother, the rotating electric motor. Because the linear motor always has to effect a reversing movement - from one end of the motor to the other and back again - it has physical drawbacks as a source of energy...

Briefs : Physical Sciences
Portable Multispectral Telescope

A telescope produces multiple video outputs representing coregistered images in multiple spectral bands that can range from ultraviolet through far infrared. Although the overall function of the telescope is partly equivalent to that of a color television camera equipped with telescopic lenses, its basic optical...

Briefs : Electronics & Computers
Pixel-Summing APS Imager With Differential Column Readout

A complementary metal oxide/semiconductor (CMOS) integrated-circuit video image detector of the active-pixel-sensor (APS) type has been designed to implement programmable multiresolution output (through summing of outputs from selected groups of neighboring pixels) in a low-power,...

Briefs : Information Technology
Computer Network for Distribution of Radiographic Images

The Radiographic Imaging Performance Support System (RIPSS) is a developmental computer network intended to serve as (1) a central electronic archive for the storage, retrieval, and analysis of radiographic images generated in nondestructive-evaluation (NDE) laboratories at Kennedy Space...

Briefs : Physical Sciences
Spectral Reflectometer for Quantifying Stress in Plants

A hand-held optoelectronic instrument has been designed to generate a quantitative indication of the loss of chlorophyll, and thus the level of stress, in plants. The instrument exploits the known spectral-reflectance characteristics associated with the chlorophyll contents of healthy and...

Briefs : Electronics & Computers
Cheaper, Lighter Biplates for Methanol Fuel Cells

Relatively inexpensive, lightweight biplates for methanol fuel cells have been proposed. The reductions in weight and cost, relative to biplates now used in methanol fuel cells, would be achieved by use of a combination of modified geometry, cheaper and lighter materials, and cheaper...

Briefs : Information Technology
Program Estimates Run Time on a Parallel Computer

The Pathcalc computer program estimates the time needed to execute a given application program on a parallel computer of given computation and network capabilities. Pathcalc can be used to analyze the effects of changes in such parameters as central-processing-unit (CPU) speed, network...

Briefs : Materials
Improved Aerogel-Based Thermal Insulation Systems

Improved aerogel-based thermal insulation systems have been developed to provide cost-effective and easier-to-handle alternatives to various types of multilayer insulation (MLI) and evacuated powder insulation now used on cryogenic equipment. The apparent thermal conductivities of the...

Briefs : Electronics & Computers
Improved Computer-Based System for Handling Shuttle Data

The Shuttle Projects Information Frontier (SPIF) Telemetry and Command Processor (TAC) is a personal-computer-based data-handling system that serves as part of an interface for transfer of data between Johnson Space Center and Goddard Space Flight Center (see figure). The data in question...

Briefs : Physical Sciences
Improved HSPES-Based MEAs for Methanol Fuel Cells

Improved membrane/electrode assemblies (MEAs) made partly from hydrogen form of sulfonated polyether sulfone (HSPES) have been developed for use in methanol fuel cells. In comparison with traditional fuel-cell MEAs made partly from a commercial perfluorosulfonic acid-based polymer, these MEAs...

Briefs : Mechanical & Fluid Systems
Visualization of Flows in Beds Packed With Spheres

The figure shows an oil tunnel and associated equipment used in experiments, using the full-flow-field tracking (FFFT) technique, to characterize flows in beds packed with poly (methyl methacrylate) spheres. The indices of refraction of the oil and the spheres were matched to make the spheres...

Briefs : Electronics & Computers
An Innovative Material for In-Chamber Semiconductor Applications

Vespel parts are made from a unique polymer by DuPont that has been called a problem solver for the semiconductor industry. Vespel SPC is a new generation of Vespel polyimide parts and shapes for semiconductor manufacturing, with improved performance and added value in etching...

Briefs : Robotics, Automation & Control
The X-36 Program: A Test Pilot's Perspective on UAV Development Testing

The Dryden Flight Research Center (DFRC) has been a partner in many uninhabited-aerial-vehicle (UAV) test programs. Our participation has largely been in the areas of technical oversight and range safety, but the X-36 program provided an opportunity to get some "stick and...

Briefs : Electronics & Computers
Transmissive Surface-Plasmon Light Valves

Transmissive light valves based on voltage-tunable color-selective absorption of light in surface plasmons are undergoing development. Like other surface-plasmon-based devices reported in a number of recent articles in NASA Tech Briefs, these light valves could be constructed in many different...

Briefs : Software
Planning and Resource Reasoning Software

"Planning and Resource Reasoning" ("PARR") is the name now applied to a scheduling methodology and to computer programs developed to implement the methodology during the years 1985 through 1987. In PARR, one uses heuristics and reactive techniques to build schedules. PARR software is generic enough to be...

Briefs : Physical Sciences
Portable Video Imager for Detecting Stress in Plants

A portable instrument can generate video images indicative of physiological stress in plants. The instrument exploits the known relationships among physiological stress in plants, loss of chlorophyll, and changes in spectral reflectance. The instrument acquires multispectral video images of a...

Briefs : Materials
PSSA/PVDF Polymer Electrolyte Membranes for CH₃OH Fuel Cells

Improved polymer electrolyte membranes for direct methanol fuel cells can be made by any of a variety of processes in which cross-linked polystyrene sulfonic acid (PSSA) is mobilized within electrochemically inert matrices of poly(vinylidene fluoride) (PVDF). Alternatively, other...

Briefs : Electronics & Computers
Satellite Radio Relay Internet Link for the South Pole

The South Pole TDRSS Relay (SPTR) is a satellite radio relay communication system that provides an Internet link for a station at the South Pole. As the name of the system suggests, the radio connection is made via the TDRSS. The northern end of the link is located at the TDRSS...

Briefs : Electronics & Computers
A 640 × 486 Long-Wavelength Infrared Camera

A rectangular integrated-circuit focal-plane array of 640 × 486 GaAs/AlxGa1 -xAs quantum-well infrared photodetectors (QWIPs) constitutes the image sensor in an experimental long-wavelength infrared camera. This is the first long-wavelength infrared camera containing...

Briefs : Software
Automated Scheduling and Reporting of Fire Inspections

A computer-based automated system for scheduling, reporting, and tracking fire inspections at Kennedy Space Center has supplanted a manual system based on paper fire-inspection reports transmitted by mail. The automated system not only minimizes the consumption of paper and other resources...

Briefs : Electronics & Computers
A Hybrid Position and Displacement Sensor

Sensor Products has recently filed two patents for, and introduced, the ASET® sensor for measuring interfacial stresses in real time. The sensor does not measure force, but rather the amount of surface area under compressive load. The principle of the ASET, which is a hybrid of a position and...

Briefs : Electronics & Computers
A Commercially Viable Asymmetric Ion Trap for Environmental Analysis

Basic research on ion-trap mass spectrometry (IT/MS) in the Environmental Molecular Sciences Laboratory (EMSL) at Pacific Northwest National Laboratory has resulted in a new patented design for an asymmetric ion trap instrument. This advancement, primarily supported by DOE...

Briefs : Electronics & Computers
Improved Ultrasonic Imaging of Microscopic Devices

Advances in time gating of ultrasonic signals in scanning acoustic microscopes have been proposed to enable detailed nondestructive examination of bonds and other interfaces deep within the interiors of such micromachined objects as high-density integrated electronic circuits and...

Briefs : Motion Control
PC Control withIntegrated Motion

PC-based control has become one of the fastest-growing automation solutions for the factory floor. Control engineers are quickly dropping their proprietary PLC boxes and replacing them with PC-based control systems to gain the benefits of open-systems architecture. Similar to the shift away from proprietary Wang...

Briefs : Robotics, Automation & Control
Robot Arm Actuated by Electroactive Polymers

The figure shows a robot arm that is essentially a miniature crane actuated by electroactive polymers. This mechanism has been constructed as part of a continuing effort to develop lightweight, compact, low-power-consumption telerobots.

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