Briefs: Medical
Exoskeletal System for Neuromuscular Rehabilitation

A system of sensors and actuators designed to fit on the lower extremities of human patients and astronauts like an exoskeleton is under development to serve diverse purposes in neuromuscular research and rehabilitation. This system will be operated under both Earth and microgravity conditions....

Studies of physical and chemical effects in the hydride-forming electrodes of rechargeable nickel/metal hydride electrochemical cells have yielded results that now guide...

Small ball (full sphere) lenses in the 0.5-mm to 3.0-mm diameter range offer a number of practical advantages for fiber-to-fiber coupling and fiber collimation. Ball lenses are...

Scientists, astronomers, optical re-searchers, and manufacturers frequently require two-axis reflective optical mechanisms to meet the requirements of robust beamsteering...

Briefs: Electronics & Computers
Compact Magnetic-Sensor Units for Detecting Mines

Compact, low-power-consumption magnetic-sensor units called "integrated sensor system" (ISS) units are being developed for detecting buried mines and arsenals without exposing human searchers...

Briefs: Electronics & Computers
Finite-Width Coplanar-Waveguide Patch Antenna

The upper part of Figure 1 illustrates an antenna derived by widening the middle strip conductor of a finite-width coplanar waveguide (FCPW) to form a rectangular patch. An FCPW offers all the...

Briefs: Manufacturing & Prototyping
Integrally Wound Skirt for Composite-Overwrapped Tank

The skirt that supports a composite-overwrapped tank would be made an integral part of the composite overwrap, according to a proposal. In current practice, the structure that supports a composite-overwrap tank usually includes a layer of rubber between the tank and its skirt. The rubber...

A crimping technique has been developed for fastening polytetrafluoroethylene (PTFE) tubes of 0.032-in. (0.81-mm) outside diameter and 0.0105-in. (0.267-mm) inside diameter onto...

Briefs: Physical Sciences
Foam Heat Exchangers

Experiments have demonstrated the feasibility of heat exchangers with flow channels containing open-cell metallic foams. Nonmetallic foams could also be used. One proposed design calls for an open-cell foam in the annular region between an inner and an outer tube, with a heat-transfer fluid flowing along the annular region...

Briefs: Robotics, Automation & Control
Human-Powered Centrifuges and Stationary Exercise Stations

Human-powered machines that can be operated as centrifuges or as stationary exercise stations have been invented. These machines are suitable for a variety of terrestrial and...

Briefs: Mechanical & Fluid Systems
High-Altitude Flight Test of the Perseus B Airplane

The Perseus B remotely piloted vehicle (RPV) has achieved a record altitude for a single-engine, propeller-driven airplane of 60,260 ft (18,367 m) on June 27, 1998. The Perseus B is one of...

Briefs: Electronics & Computers
Interlayer Stripline Transition

A proposed multilayer metal-film/dielectric-plate laminate would serve as a passive radio-frequency (RF) interlayer stripline transition. This device is designed to provide RF coupling from (a) an input...

An improved method of fabricating membrane electrode structures for methanol fuel cells is similar to the method described in the preceding article, except that in this method, the...

Briefs: Electronics & Computers
Circuit for Automatic Tunneling-Controlled Golay Cell

An automatic tunneling-controlled, micromachined Golay cell has been implemented in a multichip integrated-circuit module. The module is designed specifically for sensing infrared radiation indicative of the concentration of glucose in blood, but its low noise, high gain, and low power...

"HOTCFGM-1D" denotes a collection of four computer programs, plus the underlying theory, for calculating thermomechanical and inertial effects in axisymmetric cylindrical...

Vertical-Bloch-line (VBL) memory devices of a proposed type would include stacks of VBL memory chips plus other components (see figure on next page). Each chip would be square,...

Briefs: Physical Sciences
Details of Apparatus for Advanced Ultrasonic C-Scan Imaging

A report comprising the main contents of U. S. Patent 5,750,895 presents detailed information on the subject of "Apparatus for Advanced Ultrasonic C-Scan Imaging (GSC-13524), NASA Tech Briefs, Vol. 21, No. 4 (April 1997), page 34. The apparatus is a computer-controlled ultrasonic C-scan...

A method of computational simulation of the aerodynamic- or hydrodynamic-flow performance features of objects involves the use of neural-network mathematical models implemented in...

Briefs: Electronics & Computers
Segmented-Aperture Michelson Interferometer

In a proposed modification of the basic design of a Michelson interferometer, the beam aperture would be split into a number (N ≧ 2) of smaller areas and the optics arranged so that the beam in each area would generate a distinct segment of the overall desired interferogram. Each segment of the...

Electric arcs and electrochemical etching can be used to impart microscopic textures to surfaces of metals. In electric-arc texturing, one strikes an arc between a water-cooled...

Briefs: Robotics, Automation & Control
Miniature Lambda Sensors for Engine-Control Systems

Small, lightweight sensors that exploit the unique characteristics of nanoceramics are being developed for use in measuring air/fuel ratios in the exhaust gas flows of advanced aircraft...

Briefs: Software
Software for Operating a Forward-Link-Simulator Card

A computer program has been developed to serve as the means for setting up, controlling, and receiving information on the status of a forward-link-simulator card in a Digital Equipment Corporation (DEC) Alpha computer that runs the Digital UNIX operating system. The program performs functions...

Briefs: Electronics & Computers
Improvements in Fabrication of HgCdTe Photodetectors

Two improvements have been made to solve two problems that arise in conjunction with a fabrication process in which an HgCdTe photodetector is mounted on an alumina substrate with epoxy. Although most of the HgCdTe-photodetector industry has abandoned this process in favor of epitaxial...

Briefs: Electronics & Computers
Broad-Band GaAs/AlₓGa₁₋ₓAs QWIPs

GaAs/AlxGa1-xAs quantum-well infrared photodetectors (QWIPs) with broad-band responses are undergoing development. The broad-band responses are obtained by varying the depths and...

A robust sensor based on the electrochemical oxidation of methanol has been developed for use in measuring the concentration of methanol dissolved in water. The sensor is expected to...

Briefs: Mechanical & Fluid Systems
Model-Based Monitoring for Spacecraft Thruster Leakage

A report describes a method of detecting leakage in one of the 16 thrusters of the Cassini spacecraft. The detection method, implemented as part of the spacecraft flight software, is based on the fact that the three-axis rotational motion of a spacecraft is governed by the Euler's equation....

Monolithic, tandem two-junction InxGa1-xP/InxGa1-x As-on-Ge Solar Photovoltaic Cells are being developed. The cells are designed...

Briefs: Electronics & Computers
Mobile System for Control of a Remote Rocket-Launching Range

The Wallops Flight Facility of the Goddard Space Flight Center has designed and built in-house a Mobile Range Control System (MRCS), which is a self-contained system to be deployed in support of rocket launches at remote ranges in cases in which termination of flight may be required...

Briefs: Robotics, Automation & Control
Thermal Batteries Made With Nanostructured Material

Early experiments in a continuing research program have demonstrated that thermal batteries made from powdered solid electrode and electrolyte materials can be improved by use of smaller...

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Will Self-Erasing Chips Catch On?

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