Magazine

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 require...

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...

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) computer...

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...

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 of...

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: The...

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”...

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 hardware...

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 of...

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. MRECS...

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 for...

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 with a...

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...

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

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...

A relatively inexpensive, lightweight, durable, easy-to-operate radio-frequency (RF) instrument has been developed, along with special electromagnetic tags, for use in detecting buried objects to which the tags are attached. Each tag comprises a dipole antenna (basically, two collinear...

Software for decoding turbo codes that have been adopted as standard by the Consultative Committee for Space Data Systems is being developed along with hardware built around integrated-circuit digital signal processors (DSPs) that execute the software. The software enables reliable...

Liquid-level-measuring systems based on fiber-optics are under development as compact, lightweight alternatives to systems based on float gauges and other conventional sensors. For liquids that pose explosion hazards, fiber-optic sensors are inherently safer because they do not include electrical connections inside...