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Briefs: Mechanical & Fluid Systems
A mechanism has been designed to apply the loads (the stirring and the resection forces and torques) in self-reacted friction stir welding. This mechanism differs somewhat from mechanisms used in...
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Briefs: Mechanical & Fluid Systems
Back actuators have been proposed as alternatives to edge actuators considered previously for use in aligning hexagonal segments of lightweight segmented astronomical mirrors planned...
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Briefs: Mechanical & Fluid Systems
Figure 1 shows a salt pill and some parts of a thermally insulating, kinematic suspension system that holds the salt pill rigidly in an adiabatic demagnetization refrigerator (ADR)....
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Briefs: Physical Sciences
Semiconductor electron-spin filters of a proposed type would be based on the Rashba effect, which is described briefly below. Electron-spin filters — more precisely, sources of...
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Briefs: Physical Sciences
A batch of experimental diffusion-cooled hot-electron bolometers (HEBs), suitable for use as mixers having input frequencies in the terahertz range and output frequencies up to about a...
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Briefs: Physical Sciences
An improved optoelectronic apparatus has been developed to provide the position feedback needed for controlling the levitation subsystem of a containerless processing system. As...
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Briefs: Photonics/Optics
Optoelectronic sensors and magnetic actuators have been developed as parts of a system for controlling the relative position and attitude of two massive optical tables that float on...
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Articles: Photonics/Optics
Nano-optics is a valuably novel class of technology that takes advantage of light’s unique interaction with subwavelength, nano-scale patterned materials, and nanotechnology-enabled fabrication methods to create a broadly...
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Briefs: Mechanical & Fluid Systems
Demonstration of a Pyrotechnic Bolt-Retractor System
A paper describes a demonstration of the X-38 bolt-retractor system (BRS) on a spacecraft-simulating apparatus, called the Large Mobility Base, in NASA Flight Robotics Laboratory (FRL). The BRS design was proven safe by testing in NASA Pyrotechnic Shock Facility (PSF) before being demonstrated in...
Briefs: Mechanical & Fluid Systems
Simulating Operation of a Planetary Rover
Rover Analysis, Modeling, and Simulations (ROAMS) is a computer program that simulates the operation of a robotic vehicle (rover) engaged in exploration of a remote planet. ROAMS is a rover-specific extension of the DARTS and Dshell programs, described in prior NASA Tech Briefs articles, which afford...
Briefs: Mechanical & Fluid Systems
Microvalves containing silicone-rubber seals actuated by heating and cooling of paraffin have been proposed for development as integral components of microfluidic systems. In comparison with...
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Briefs: Mechanical & Fluid Systems
Flexible Shields for Protecting Spacecraft Against Debris
A report presents the concept of Flexshield —a class of versatile, light-weight, flexible shields for protecting spacecraft against impacts by small meteors and orbiting debris. The Flexshield concept incorporates elements of, but goes beyond, prior space-craft-shielding concepts,...
Briefs: Mechanical & Fluid Systems
Controllable Curved Mirrors Made From Single-Layer EAP Films
A document proposes that light-weight, deployable, large- aperture, controllable curved mirrors made of reflectively coated thin electroactive-polymer (EAP) films be developed for use in spaceborne microwave and optical systems. In these mirrors, the EAP films would serve as both...
Briefs: Electronics & Computers
The figure depicts the major functional blocks of a system, now undergoing development, for conditioning neural signals acquired by electrodes implanted in a brain. The overall functions...
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Briefs: Electronics & Computers
It has been shown that a non-square (NS)22n+1-ary (where n is a positive integer) quadrature amplitude modulation [(NS)22n+1-QAM] has inherent memory that can be exploited to obtain coding...
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Briefs: Test & Measurement
Simple, passive instruments have been developed for measuring the exposure of material specimens to vacuum ultraviolet (VUV) radiation from the Sun. Each instrument contains a silicon photodiode...
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Briefs: Test & Measurement
An apparatus and technique have been devised for measuring the radiation pattern of a microwave patch antenna that is one of a number of identical units that have been...
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Briefs: Test & Measurement
The figure depicts an apparatus for mechanical testing of nuts In the original application for which the apparatus was developed, the nuts are of a frangible type designed for use with...
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Briefs: Information Technology
Further Improvement in 3DGRAPE
"3DGRAPE/AL:V2" denotes version 2 of the Three - Dimensional Grids About Anything by Poisson's Equation with Upgrades from Ames and Langley computer program. The preceding version, 3DGRAPE/AL, was described in "Improved 3DGRAPE" (ARC-14069) NASA Tech Briefs ,Vol.21, No.5 (May 1997), page 66. These programs are so...
Briefs: Information Technology
Ground Support Software for Spaceborne Instrumentation
ION is a system of ground support software for the ion and neutral mass spectrometer (INMS) instrument aboard the Cassini spacecraft. By incorporating commercial off-the-shelf database, Web server, and Java application components, ION offers considerably more ground-support-service capability...
Briefs: Information Technology
MER SPICE Interface
MER SPICE Interface is a software module for use in conjunction with the Mars Exploration Rover (MER) mission and the SPICE software system of the Navigation and Ancillary Information Facility (NAIF) at NASA's Jet Propulsion Laboratory. (SPICE is used to acquire, record, and disseminate engineering, navigational, and other...
Briefs: Information Technology
Analyzing Contents of a Computer Cache
The Cache Contents Estimator (CCE) is a computer program that provides information on the contents of level-1 cache of a PowerPC computer. The CCE is configurable to enable simulation of any processor in the PowerPC family. The need for CCE arises because the contents of level-1 caches are not available to...
Briefs: Information Technology
Discrepancy Reporting Management System
Discrepancy Reporting Management System (DRMS) is a computer program designed for use in the stations of NASA's Deep Space Network (DSN) to help establish the operational history of equipment items; acquire data on the quality of service provided to DSN customers; enable measurement of service performance;...
Briefs: Information Technology
Product development is becoming increasingly global and as a result, new challenges have emerged, such as coordinating geographically dispersed teams of suppliers...
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Briefs: Physical Sciences
Part 2 of a Computational Study of a Drop-Laden Mixing Layer
This second of three reports on a computational study of a mixing layer laden with evaporating liquid drops presents the evaluation of Large Eddy Simulation (LES) models.
Briefs: Physical Sciences
A proposed technique for locating concealed objects (especially small antipersonnel land mines) involves the acquisition and processing of spectral signatures over broad microwave...
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Briefs: Medical
A solution has been formulated to preserve deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) in specimens of blood, saliva, and other bodily fluids. Specimens of this type are...
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Briefs: Medical
A rapid, sensitive test using chemiluminescent oligodeoxynucleotide probes has been developed for detecting, identifying, and enumerating intact cells. The test is intended especially for...
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Briefs: Materials
Brazing SiC/SiC Composites to Metals
Experiments have shown that active brazing alloys (ABAs) can be used to join SiC/SiC composite materials to metals, with bond strengths sufficient for some structural applications. The SiC/SiC composite coupons used in the experiments were made from polymer-based SiC fiber preforms that were chemical-vapor-...