August 2002

Briefs : Electronics & Computers
“Morphing” in Evolutionary Synthesis of Electronic Circuits

A method of automated evolutionary synthesis of electronic circuits has been augmented by a concept called “morphing through fuzzy topologies.” Previous versions of the method provided for the evaluation of “crisp” topologies were precisely specified by open/closed (on/off)...

Briefs : Electronics & Computers
Miniature Fuel Cells for Small, Portable Electronic Devices

Miniature fuel cells in a “flat-pack” configuration are being developed as alternatives to recharge- able batteries in cellular telephones, laptop computers, and other small, portable electronic devices. These fuel cells exploit the electrochemical oxidation of organic fuel (usually...

Briefs : Materials
Internal-Combustion Engines With Ringless Carbon Pistons

Internal-combustion engines would be constructed with cylinders and ringless pistons made of lightweight carbon/carbon composite materials, according to a proposal. This proposal is a logical extension of previous research that showed that engines that contain carbon/carbon pistons with...

Briefs : Electronics & Computers
Mixtrinsic Evolutionary Synthesis of Electronic Circuits

A method of automated synthesis of analog and/or digital electronic circuits involves evolution in both software simulations and hardware. Heretofore, the evolutionary auto- mated synthesis of electronic circuits has been accomplished by use of either software simulations or hardware, but...

Briefs : Electronics & Computers
Sequential-Color LED Illumination for Reflective Microdisplays

Integrated silicon microdisplays, such as liquid-crystal-on-silicon (LCOS) devices, are becoming the most effective image source for high-resolution viewfinders, head- mounted displays, and helmet-mounted displays (HMDs). Since these microdisplays are reflective in nature, they...

Briefs : Electronics & Computers
Multifunction Input/Output Integrated Circuits

Integrated circuits that would perform a variety of analog-signal, digital- signal, and power input/output functions have been proposed. Conceived for use as versatile, fault-tolerant interfaces among components and subsystems of spacecraft, these multifunction integrated circuits could also be...

Briefs : Electronics & Computers
SEU-Tolerant Flip-Flops

Several improvements in the designs of flip-flop circuits that are parts of logic circuits have been proposed to reduce the incidence of logic errors associated with single- event upsets (SEUs) [bit flips caused by incident energetic ionizing particles]. Traditionally, radiation-hardened integrated circuits have been...

Briefs : Electronics & Computers
Console for an Overhead-Bridge Crane

Human factors engineering has been applied to the design of an overheadbridge crane control console for use by a seated operator in a clean-room environment. The crane console provides the operator with the ability to lift and move loads up to 27.5 tons (24.9 tonnes) in three vertical speed ranges and three...

Briefs : Electronics & Computers
High-Temperature Coils for Electromagnets

Coiled electric wires have been developed for use in electromagnets that operate at high temperatures. Examples of such electromagnets could include the actuators in magnetic bearings in advanced gas turbines.

Briefs : Software
Software Generates Sequences of Operations for a Mars Rover

Automated Rover Sequence Generation (ARSG) is a prototype computer program for ground-based automatic generation of sequences of commands that can be used for a robotic exploratory vehicle (rover) on Mars. ARSG is based on the Automated Scheduling and Planning Environment (ASPEN)...

Briefs : Software
Web-Based Software Service Improves Space-Shuttle Processing

Human data-transfer from space-shuttle checkout systems to shuttle business systems is slow, error-prone, and expensive. The Operations and Maintenance Requirement Specification-Automated Buy Off System (OMRS-ABOS) is a software system that automatically transfers test-validation data...

Briefs : Software
Program Analyzes Current Signatures of Solenoid Valves

A computer program processes signal data in the instrument described in “Current- Signature Sensor for Diagnosing Solenoid Valves” (KSC-12152), NASA Tech Briefs, Vol. 25, No. 9 (September 2001), page 30. Ten-bit samples of the electric current in a solenoid valve are acquired at a rate...

Briefs : Software
Program Predicts Radiation Forces on a Satellite

A computer program predicts the radiation forces on the TOPEX/ Poseidon satellite at any point in its orbit around the Earth. The program performs a unified analysis of the thermal, radiative, power-generation, and orbital-mechanics aspects of operation because these aspects are inter- dependent:...

Briefs : Software
OwWwL and AgentNation: Knowledge-Robot Software

OwWwL and Agent- Nation are Java- language computer programs that act together, quickly scanning Internet databases for relevant information, then organizing the infor- mation into a format suited to the user. OwWwL is a search- engine program that, like other such programs, includes a “spider”...

Briefs : Software
Application Fault Injector

Application Fault Injector (AFI) is a simple com- puter program for testing the fault tolerance of other programs. AFI is a library of subroutines designed to inject faults into memory, data structures, and registers. The library is modular, can easily be extended, and can easily be ported to different computer...

Briefs : Materials
Reducing Wear and Friction of CVD Diamond Films

Progress has been achieved in continuing research directed toward increasing the wear resistance and enhancing the self- lubrication properties of chemical-vapor-deposited (CVD) diamond films. Such films are potentially useful as friction- and wear-reducing coats on sliding mechanical components...

Briefs : Mechanical & Fluid Systems
Water-Jet Accelerator for Launching a Spacecraft

A proposed ground- based apparatus would accelerate a spacecraft to speed of about mach 1, thus making it possible to increase the payload and/or reduce the cost of launching the space- craft into orbit. The apparatus would include a track along which the spacecraft would ride on a sled. Hundreds...

Briefs : Mechanical & Fluid Systems
Modular, Highly Maintainable, and Flexible Control Software

Model Rocket Engine Software System (MRECS) is a system of control software that was originally intended for use in controlling rocket engines but is also applicable to almost any real-time, closed- loop process-control system — for example, the feedback control system of a robot....

Briefs : Manufacturing & Prototyping
Low-Plasticity Burnishing

Low-plasticity burnishing (LPB) has been devel- oped as an affordable means of imparting residual compressive stresses to surface layers of metal parts (especially engine components) in order to increase their fatigue lives. Heretofore, surface compressive stresses to enhance the fatigue lives have been produced,...

Briefs : Physical Sciences
System for Detecting Hazardous Gases at Multiple Locations

The Hazardous Gas Detection System 2000 (HGDS 2000) is the latest in a series of instrumentation systems for detecting gases leaking from a space shuttle on a launch pad. The HGDS is a fully redundant system that includes analog and digital electronic control circuitry and a sub- system...

Briefs : Physical Sciences
Temperature-Compensation Method for High-Temperature Strain Gauges

A relatively simple and inexpensive method of fabricating a temperature-compensation element for high- temperature strain gauges has been devised. This element, connected in the adjacent arm of a Wheatstone bridge, provides temperature compensation for an active strain gauge...

Briefs : Information Technology
Windowed Revocation of Public-Key-Encryption Certificates

Windowed revocation is a technique for the revocation of the digital certificates that provide assurance of the auth- enticity and integrity of public encryption keys and associated private decryption keys. These keys are used to protect the privacy of communications via the Internet. The...

Briefs : Software
Mechanical Event Simulation for MEMS Design

This report examines the simulation of the dynamic behavior of a MEMS (Micro Electro Mechanical Systems) optical switch in order to meet the Telcordia telecommunication industry standards for shock. The setup of the finite element model of the telecommunications device is discussed in detail, along...

Briefs : Physical Sciences
Narrowband Tunable Optical Filter Using Fiber Bragg Gratings

Research at Langley Research Center has developed a special fiber- Bragg grating optical filter for use in aircraft or spaceborne differential absorption lidar (DIAL) systems for measuring water vapor in the atmosphere of the Earth. The filter is an optical fiber containing two Bragg...

Briefs : Information Technology
Technical Background of Special Bus-Driver Software

A short report discusses the technical back- ground of, and the need for, special bus-driver software for part of a test-bed computer system that is to be used in experi- mentation for develo- pment of advanced avionics. The system features a scalable, fault-tolerant, distributed architecture...

Briefs : Mechanical & Fluid Systems
Advances in Cooperative Transport by Two Mobile Robots

Special gimbal mechanisms and algorithms that implement decentralized compliant control have been developed for use in research on the sensors, the actuators, and the design and functional requirements for systems of multiple mobile robots cooperating in site-clearance and construction...

Briefs : Mechanical & Fluid Systems
Magnetostrictive Motor and Circuits for Robotic Applications

A magnetostrictive motor and its drive circuit and control system have been designed to be especially suitable for robotic applications in which there are requirements for precise, high-force linear actuators. The motor includes a laminated armature made of the magnetostrictive alloy...