Tech Briefs

A comprehensive library of technical briefs from engineering experts at NASA and major government, university, and commercial laboratories covering all aspects of innovations in electronics, software, photonics, imaging, motion control, automation, sensors, test, materials, manufacturing, mechanical, and mechatronics.

Briefs : Electronics & Computers
Signaling-and-Detection Scheme for Beacon Monitoring

A signaling-and-detection scheme has been proposed for use in conjunction with the remote-monitoring concept described in "Beacon Monitoring Would Reduce Interactions With Remote Systems" (NPO-19706), NASA Tech Briefs, Vol. 21, No. 5 (May 1997), page 54. To recapitulate: A remote system (a...

Briefs : Robotics, Automation & Control
Manipulator System for a Robotic Vehicle

A prototype manipulator system that includes two different arms has been tentatively selected for use on a semiautonomous robotic vehicle called Rocky 7 (see figure). [A previous version of this vehicle with a single manipulator arm was described in "High-Performance Robotic Vehicle" (NPO-19921) NASA Tech...

Briefs : Physical Sciences
Automated Window Inspection Device

The Automated Window Inspection Device (AWID) is a prototype apparatus for computer-controlled, noncontact inspection of windows, with reproducible positioning and electronic recording of data on the locations, sizes, and depths of flaws. The AWID was developed to accelerate and facilitate (1) postflight...

Briefs : Photonics/Optics
Multimode Optical Fiber as Imaging Probe

A proposed electro-optical image-processing system would enable remote viewing of an object through a multimode optical fiber, as though the fiber were a conventional image-transmitting optic like a lens or prism. Ordinarily, it would be impractical to use a multimode optical fiber as an imaging probe or...

Briefs : Mechanical & Fluid Systems
High-Wind Masts for Meteorological Instruments

Rigid, guyed masts of a proposed type for supporting meteorological instruments would be designed to withstand considerably stronger winds than those conventionally used. The proposed fairings would also help minimize perturbations of airflows and thereby minimize the contaminating effects of the...

Briefs : Physical Sciences
Mathematical Model of Pyrolysis of Biomass Particles

A mathematical model of a special class of solid/fluid chemical reactions has been developed for use in analyzing the pyrolysis of particles of cellulose, wood, and similar biomass materials. Although it involves some simplifying assumptions (as do all models of chemical and physical...

Briefs : Physical Sciences
Mathematical Model of a Direct-Contact Pyrolysis Reactor

A mathematical model has been developed for use in assessing the performances of direct-contact pyrolysis reactors used to convert particles of raw biomass materials (usually small wood chips) into char, tar, and gas. The optimal designs are here considered to be those that maximize the...

Briefs : Physical Sciences
Protecting a Micromachined Accelerometer During Handling

A highly sensitive micromachined accelerometer that is intended to be exposed to very small accelerations during operation incorporates features for protection against much larger accelerations during handling and transport. More specifically, the accelerometer is designed to measure...

Briefs : Information Technology
Software for Improving Operational Processes

The Schedule and Cost Risk Analysis Modeling System (SCRAM) computer program identifies important sources of schedule and cost risks in an operational process. The related Process Analysis and Improvement Support System (PASS) program assists in the overall analysis and improvement of an operational...

Briefs : Electronics & Computers
Multimedia Operator Interface for a Health-Care Robot

An operator interface is undergoing development along with other subsystems of a robot that would assist in caring for elderly and disabled patients. This development has been initiated in anticipation of an increasing need for long-term care, in both home and hospital environments, with...

Briefs : Information Technology
Software for Planning in a Hierarchical Processing Environment

Decision-support software based on discrete-event simulation (DES) has been undergoing development for use in planning and scheduling work in the Orbiter Processing Facility (OPF) at Kennedy Space Center. The software is also suitable for adaptation to similar use in other facilities...

Briefs : Physical Sciences
Evaluation of Droplet-Evaporation Models for Gas/Liquid Flow

A report presents an evaluation of eight mathematical models of the evaporation of liquid droplets — models that are used in the numerical simulation of a variety of gas/liquid flows, including cooling sprays, burning liquid-fuel sprays, fire-suppression sprays, and...

Briefs : Software
Program for Simulating Dynamics of Multibody Systems

The Dynamics Algorithms for Real-Time Simulation (DARTS) computer program solves the equations of motion of tree-topology, flexible, and/or multibody mechanical systems as diverse as molecules, mechanisms, robots, spacecraft, and ground vehicles. It has proven to be particularly useful for...

Briefs : Electronics & Computers
Hybrid Superconductor/Semiconductor Planar Oscillators

Hybrid high-temperature-superconductor (HTS)/semiconductor planar oscillator circuits that operate at a frequency of 8.4 GHz have been developed. In the original intended application, one of these circuits would serve as a local oscillator in a cryogenic heterodyne receiver in a spaceborne...

Briefs : Information Technology
Work-Measurement and Methods-Analysis Studies of the OPF

Two reports describe early phases of continuing studies directed toward the selection and adaptation of industrial work-measurement and methods-analysis procedures for application to the Orbiter Processing Facility (OPF) at Kennedy Space Center. These studies were prompted by a need to...

Briefs : Photonics/Optics
A High-Repetition-Rate Optical Communications Source

High-speed communications, medical applications, and semiconductor processing would all benefit from a laser that can produce stable, high-repetition-rate pulses at 1.55 micrometers. One goal of the Naval Research Laboratory's program in ultrahigh-speed communications research is to develop...

Briefs : Photonics/Optics
Transmitting Power to Sensor Circuitry via Modulated Light

Modulated (as opposed to steady) light can be used in the optical transmission of power to remotely located sensor circuitry in a system like that described in the preceding article, "General-Purpose Optically Powered Sensor and Control System" (NPO-19604). This is analogous to the use...

Briefs : Physical Sciences
Elevation Corrections for Absolute-Pressure Measurements

A method of correcting absolute-air-pressure measurements for small differences in the elevations of pressure taps and pressure transducers has been devised. The variation in air pressure with elevation is well documented; nevertheless, in such disciplines as process control and...

Briefs : Mechanical & Fluid Systems
Self-Contained Impact-Type Damper for Bellows-Type Face Seals

A self-contained impact-type damper for a bellows-type face seals suppresses dynamic instability or chatter. In current practice, damping in a typical seal is accomplished through rubbing contact between a ground (a stationary member) and a bellows or carrier as the seal translates....

Briefs : Photonics/Optics
General-Purpose Optically Powered Sensor and Control System

The figure schematically illustrates a prototype general-purpose, microprocessor-based sensor and control system in which power, data, and control signals are transmitted via optical fibers. This system serves as an experimental model for the further development of networks of remote...

Briefs : Information Technology
Model for Investigating Human Factors in an Organization

The Kennedy Space Center Human Factors Event Evaluation Model is a model to facilitate long-term gathering and analysis of data to investigate the effects of human factors on the operations of a complex organization. The model was developed specifically for use in comprehensive...

Briefs : Robotics, Automation & Control
All-Terrain Vehicle With Self-Righting and Pose Control

A small prototype robotic all-terrain vehicle features a unique drive and suspension system that affords capabilities for self righting, pose control, and enhanced maneuverability for passing over obstacles. The vehicle is designed for exploration of planets and asteroids, and could just...

Briefs : Photonics/Optics
Measuring Flow Using Spectrally Resolved Rayleigh Scattering

An experimental study has been conducted to demonstrate the feasibility of using spectrally resolved Rayleigh scattering to nonintrusively measure the instantaneous properties of the flow in a small supersonic wind tunnel. Unlike conventional probe flow measurements, Rayleigh...

Briefs : Information Technology
Consortium Benchmarking in a Competitive Environment

The Kennedy Benchmarking Clearinghouse (KBC) is an organization for implementing an emerging methodology called "consortium benchmarking" in a competitive business environment. The partners in the KBC include NASA Kennedy Space Center and a number of its contractors. Within the KBC, the...

Briefs : Physical Sciences
Thermographic Detection of Defects in Refractory Composites

Significant effort and resources are being expended to develop ceramic-matrix composite (CMC), metal-matrix composite (MMC), and polymer-matrix composite (PMC) materials for high-temperature engine components and other parts in advanced aircraft. The development of composite materials...

Briefs : Photonics/Optics
Pulse Shepherding in Nonlinear Fiber Optics

Pulse shepherding is a nonlinear signal-propagation phenomenon that can occur when several pulses of light at different wavelengths are launched simultaneously or nearly simultaneously along the same single-mode optical fiber under suitable conditions. As its name suggests, pulse shepherding involves...

Briefs : Software
Software for Scheduling Use of Shared Resources

The Quick Utility for Intelligence Planning and Scheduling (QUIPS) computer program automates the scheduling of resources that must be shared among multiple tasks or groups. Designed to aid coordination of military intelligence operations at the division and brigade levels, QUIPS might also prove...

Briefs : Mechanical & Fluid Systems
Passive Magnetic Bearings With Ferrofluid Stabilization

Permanent-magnet rotary bearings with ferrofluid stabilization in the axial degree of freedom are undergoing development. These bearings are totally passive, yet stable in all degrees of freedom. In contrast, previously developed electromagnet and permanent-magnet bearings all exhibit...

Briefs : Motion Control
Large Gimbal Mount Enables Focal-Plane Testing

The latest missile guidance and tracking guidance systems deliver unprecedented performance, in terms of range, precision, and the ability to function in very unfavorable atmospheric conditions. These systems rely on a new generation of high-resolution, multifunction focal plane arrays to image...

Briefs : Electronics & Computers
ASIC for Viterbi Decoding With 2 ≤ K ≤ 15 and 1/2 ≥ r ≥ 1/6

An application-specific integrated circuit (ASIC) serves as a building block for a digital system that effects maximum-likelihood decoding of a Viterbi code (a binary convolutional error-correcting code) with a constraint length (K) in the range of 2 through 15 and a rate (r) in...

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