September 2005

Briefs : Electronics & Computers
Medium-Frequency Pseudonoise Georadar

Ground-probing radar systems featuring medium-frequency carrier signals phase-modulated by binary pseudonoise codes have been proposed. These systems would be used to locate and detect movements of subterranean surfaces; the primary intended application is in warning of the movement of underground water...

Briefs : Electronics & Computers
Front-Side Microstrip Line Feeding a Raised Antenna Patch

An improved design concept for a printed-circuit patch antenna and the transmission line that feeds the patch calls for (1) a microstrip transmission line on the front (radiative) side of a printed-circuit board based on a thin, high-permittivity dielectric substrate; (2) using the...

Briefs : Semiconductors & ICs
Making AlNx Tunnel Barriers Using a Low-Energy Nitrogen-Ion Beam

A technique based on accelerating positive nitrogen ions onto an aluminum layer has been demonstrated to be effective in forming thin (<2 nm thick) layers of aluminum nitride (AlNx) for use as tunnel barriers in Nb/Al-AlNx/Nb superconductor/ insulator/ superconductor (SIS)...

Briefs : Semiconductors & ICs
Making Wide-IF SIS Mixers With Suspended Metal-Beam Leads

A process that employs silicon-on-insulator (SOI) substrates and silicon (Si) micromachining has been devised for fabricating wide intermediate frequency band (wide-IF) superconductor/ insulator/ superconductor (SIS) mixer devices that result in suspended gold beam leads used for...

Briefs : Mechanical & Fluid Systems
Rugged Iris Mechanism

A rugged iris mechanism has been designed to satisfy several special requirements, including a wide aperture in the “open” position, full obscuration in the “closed” position, ability to function in a cryogenic or other harsh environment, and minimization of friction through minimization of the number of components....

Briefs : Mechanical & Fluid Systems
Alignment Stage for a Cryogenic Dilatometer

A three degree of freedom alignment stage has been designed and built for use in a cryogenic dilatometer that is used to measure thermal strains. The alignment stage enables precise adjustments of the positions and orientations of optical components to be used in the measurements and, once adjustments...

Briefs : Information Technology
Generating Solid Models From

A method of generating solid models of terrain involves the conversion of topographical data into a form useable by a rapid-prototyping (RP) machine. The method was developed to enable the use of the RP machine to make solid models of Martian terrain from Mars Orbiter laser-altimeter topographical data. The method is...

Briefs : Information Technology
Computationally Lightweight Air-Traffic-Control Simulation

An algorithm for computationally lightweight simulation of automated airtraffic control (ATC) at a busy airport has been derived. The algorithm is expected to serve as the basis for development of software that would be incorporated into flight-simulator software, the ATC component of...

Briefs : Materials
Low-Density, Aerogel-Filled Thermal- Insulation Tiles

Aerogel fillings have been investigated in a continuing effort to develop low-density thermal-insulation tiles that, relative to prior such tiles, have greater dimensional stability (especially less shrinkage), equal or lower thermal conductivity, and greater strength and durability. In...

Briefs : Materials
High-Performance Polymers Having Low Melt Viscosities

High-performance polymers that have improved processing characteristics, and a method of making them, have been invented. One of the improved characteristics is low (relative to corresponding prior polymers) melt viscosities at given temperatures. This characteristic makes it possible to...

Briefs : Materials
Diamond-Coated Carbon Nanotubes for Efficient Field Emission

Field-emission cathodes containing arrays of carbon nanotubes coated with diamond or diamondlike carbon (DLC) are undergoing development. Multiwalled carbon nanotubes have been shown to perform well as electron field emitters. The idea underlying the present development is that by...

Briefs : Materials
PETIs as High-Temperature Resin-Transfer-Molding Materials

Compositions of, and processes for fabricating, high-temperature composite materials from phenylethynyl-terminated imide (PETI) oligomers by resin-transfer molding (RTM) and resin infusion have been developed. Composites having a combination of excellent mechanical properties and...

Briefs : Materials
Nonflammable, Hydrophobic Aerogel Composites for Insulation

Aerogel composites that are both nonflammable and hydrophobic have been developed for use as lightweight thermal- insulation materials for cryogenic systems. Aerogels are well known in the industry for their effectiveness as thermal insulators under cryogenic conditions, but the...

Briefs : Materials
Advanced Ablative Insulators and Methods of Making Them

Advanced ablative (more specifically, charring) materials that provide temporary protection against high temperatures, and advanced methods of designing and manufacturing insulators based on these materials, are undergoing development. These materials and methods were conceived in an effort...

Briefs : Materials
Improved Anode Coatings for Direct Methanol Fuel Cells

Two perfluoroalkanesulfonic acids and perfluoroalkanesulfonimides have shown promise as anodecoating materials for improving the performances of direct methanol fuel cells (DMFCs). Heretofore, the state-of-the-art material commonly used for coating anodes in DMFCs has been Nafion™-H — a...

Briefs : Software
Generic Kalman Filter Software

The Generic Kalman Filter (GKF) software provides a standard basis for the development of application-specific Kalman-filter programs. Historically, Kalman filters have been implemented by customized programs that must be written, coded, and debugged anew for each unique application, then tested and tuned with...

Briefs : Software
ANTLR Tree Grammar Generator and Extensions

A computer program implements two extensions of ANTLR (Another Tool for Language Recognition), which is a set of software tools for translating source codes between different computing languages. ANTLR supports predicated-LL(k) lexer and parser grammars, a notation for annotating parser grammars to...

Briefs : Software
Custom Sky-Image Mosaics From NASA's Information Power Grid

yourSkyG is the second generation of the software described in "yourSky: Custom Sky-Image Mosaics via the Internet" (NPO-30556), NASA Tech Briefs, Vol. 27, No. 6 (June 2003), page 45. Like its predecessor, yourSkyG supplies custom astronomical image mosaics of sky regions specified by...

Briefs : Software
Computing Gravitational Fields of Finite-Sized Bodies
A computer program utilizes the classical theory of gravitation, implemented by means of the finite-element method, to calculate the near gravitational fields of bodies of arbitrary size, shape, and mass distribution. The program was developed for application to a spacecraft and to floating...
Briefs : Software
Software for Optimizing Plans Involving Interdependent Goals
A computer program enables construction and optimization of plans for activities that are directed toward achievement of goals that are interdependent. Goal interdependence is defined as the achievement of one or more goals affecting the desirability or priority of achieving one or more...
Briefs : Software
International Space Station Electric Power System Performance Code - SPACE

The System Power Analysis for Capability Evaluation (SPACE) software analyzes and predicts the minute-byminute state of the International Space Station (ISS) electrical power system (EPS) for upcoming missions as well as EPS power generation capacity as a function of ISS...

Briefs : Software
Path Following With Slip Compensation for a Mars Rover

A software system for autonomous operation of a Mars rover is composed of several key algorithms that enable the rover to accurately follow a designated path, compensate for slippage of its wheels on terrain, and reach intended goals. The techniques implemented by the algorithms are visual...

Briefs : Software
Software for Automation of Real-Time Agents, Version 2

Version 2 of Closed Loop Execution and Recovery (CLEaR) has been developed. The previous version was reported in “Software for Automation of Real-Time Agents” (NPO-21040), NASA Tech Briefs, Vol. 26, No. 7 (July 2002), page 34. To recapitulate: CLEaR is an artificial intelligence computer...

Briefs : Software
LabVIEW Interface for PCI-SpaceWire Interface Card

This software provides a LabView interface to the NT drivers for the PCI-SpaceWire card, which is a peripheral component interface (PCI) bus interface that conforms to the IEEE-1355/ SpaceWire standard.

Briefs : Software
Software for Engineering Simulations of a Spacecraft

Spacecraft Engineering Simulation II (SES II) is a C-language computer program for simulating diverse aspects of operation of a spacecraft characterized by either three or six degrees of freedom.

Briefs : Software
Component-Based Visualization System

A software system has been developed that gives engineers and operations personnel with no "formal" programming expertise, but who are familiar with the Microsoft Windows operating system, the ability to create visualization displays to monitor the health and performance of aircraft/spacecraft.

Briefs : Software
Comprehensive Micromechanics-Analysis Code Version 4.0

Version 4.0 of the Micromechanics Analysis Code With Generalized Method of Cells (MAC/GMC) has been developed as an improved means of computational simulation of advanced composite materials.

Briefs : Software
Program for Weibull Analysis of Fatigue Data

A Fortran computer program has been written for performing statistical analysis of fatigue-test data that are assumed to be adequately represented by a two-parameter Weibull distribution. This program calculates the following:

Briefs : Software
Facilitating Navigation Through Large Archives

Automated Visual Access (AVA) is a computer program that effectively makes a large collection of information visible in a manner that enables a user to quickly and efficiently locate information resources, with minimal need for conventional keyword searches and perusal of complex hierarchical...

Briefs : Manufacturing & Prototyping
Treatments To Produce Stabilized Aluminum Mirrors for Cryogenic Uses

Five metallurgical treatments have been tested as means of stabilizing mirrors that are made of aluminum alloy 6061 and are intended for use in cryogenic applications. Aluminum alloy 6061 is favored as a mirror material by many scientists and engineers. Like other alloys, it...

Briefs : Manufacturing & Prototyping
Vehicle Maintenance Shelters Meet Structural Requirements Through FEA Analysis
Anchor Industries supplies tents and fabric products to the outdoor amusement and entertainment industries, and municipalities. With their experience in producing portable structures, Anchor re-entered the military market of vehicle maintenance shelters (VMS). The first...
Briefs : Physical Sciences
Compact Infrasonic Windscreen

A compact windscreen has been conceived for a microphone of a type used outdoors to detect atmospheric infrasound from a variety of natural and man-made sources. Wind at the microphone site contaminates received infrasonic signals (defined here as sounds having frequencies <20 Hz), because a microphone cannot...

Briefs : Physical Sciences
Automated Counting of Particles To Quantify Cleanliness

A machine vision system, similar to systems used in microbiological laboratories to count cultured microbes, has been proposed for quantifying the cleanliness of nominally precisely cleaned hardware by counting residual contaminant particles. The system would include a microscope equipped...

Briefs : Physical Sciences
Phase Correction for GPS Antenna With Nonunique Phase Center

A method of determining the position and attitude of a body equipped with a Global Positioning System (GPS) receiver includes an accounting for the location of the nonunique phase center of a distributed or wraparound GPS antenna. The method applies, more specifically, to the case in...

Briefs : Physical Sciences
Sol-Gel Glass Holographic Light-Shaping Diffusers

Holographic glass light-shaping diffusers (GLSDs) are optical components for use in special-purpose illumination systems (see figure). When properly positioned with respect to lamps and areas to be illuminated, holographic GLSDs efficiently channel light from the lamps onto specified areas with...

Briefs : Physical Sciences
Wavelength Translation Using SFP Transceivers Enables Extension of Optical-Communication Links

Optical-Electrical-Optical (OEO) wavelength translation (WT) based on small-form-factor pluggable (SFP) transceivers is meeting with increased interest in metro optical-network applications. It provides a flexible and low-cost solution when it...

Briefs : Physical Sciences
Handheld Imaging Device for Security Applications

A standalone, handheld, through-wall radar unit is under development to provide three-dimensional feedback on the location and movement of people inside buildings. Applications include military and emergency service such as hostage situations and search and rescue. The unit, which can be held...

Briefs : Physical Sciences
Software Analyzes Heat Buildup in VCSELs

Internal heating is a key issue for vertical cavity surface emitting lasers (VCSELs), a semiconductor microlaser diode that emits light in a cylindrical beam vertically from the surface of a fabricated wafer. They generally have higher thermal impedance than edgeemitting lasers and are fairly efficient...

Briefs : Physical Sciences
Broadband External-Cavity Diode Laser

A broadband external-cavity diode laser (ECDL) has been invented for use in spectroscopic surveys preparatory to optical detection of gases. Heretofore, commercially available ECDLs have been designed, in conjunction with sophisticated tuning assemblies, for narrow- band (and, typically, single-frequency)...

Briefs : Physical Sciences
High-Efficiency Solar Cells Using Photonic-Bandgap Materials

Solar photovoltaic cells would be designed to exploit photonic-bandgap (PBG) materials to enhance their energy- conversion efficiencies, according to a proposal. Whereas the energy-conversion efficiencies of currently available solar cells are typically less than 30 percent, it has...

Products : Electronics & Computers
Flash Drive Records Unmanned NASA Balloon Flight Data
BiTMICRO® E-Disk® flash drive
BiTMICRO® Networks
Fremont, CA

The Cosmic Rays Energetics and Mass (CREAM) project is a NASA-sponsored high-altitude balloon experiment led by the University of Maryland in collaboration with...

Products : Photonics/Optics
Cambridge Consultants, Boston, Massachusetts

A standalone, handheld, through-wall radar unit is under development to provide three-dimensional feedback on the location and movement of people inside buildings. Applications include military and emergency service such as hostage situations and search and rescue. The unit, which can be held against...

Articles : Medical
Diverse Technologies Enable Today's Medical Breakthroughs

As advances in cellular biology, gene mapping, and other areas of medicine continue, amazing technologies for diagnosing, treating, and even curing diseases are emerging. Specifically, new technologies are being developed to fight the war against cancer, including advances in imaging and...

Briefs : Photonics/Optics
Finisar Corporation, Sunnyvale, California, and COMSOL, Inc., Burlington, Massachusetts

Internal heating is a key issue for vertical cavity surface emitting lasers (VCSELs), a semiconductor micro laser diode that emits light in a cylindrical beam vertically from the surface of a fabricated wafer. They generally have higher thermal impedance than...

Products : Electronics & Computers
Single-Board Computer Aids in Space Craft Control
SCS750 single-board computer
Maxwell Technologies
San Diego, CA

The National Polar-orbiting Operational Environment Satellite System (NPOESS) is a $6-billion, multi-year program with Northrop Grumman Space Technology (NGST) that will...

Briefs : Materials
Stable Polyimides for Terrestrial and Space Uses

Polyimides of a recently developed type have an attractive combination of properties, including low solar absorptivity (manifested as low color) when cast into thin films, resistance to atomic oxygen and ultraviolet radiation, solubility in organic solvents, high glass-transition temperatures...