October 2002

Briefs : Software
Embeddable Fuzzy-Logic-Toolkit Software for Tcl/Tk

A computer program of the fuzzy-logictoolkit type has been devel- oped as a relatively simple, portable, highly compatible, means of providing fuzzy-logic reasoning capabilities for control and expert-system applications.

This program is designed to work with the high-level scripting language...

Briefs : Software
Program Analyzes Use of Registers by Another Program

Regprof is a computer program that analyzes the use of registers by another program that runs on a PowerPC

750 (or equivalent) computer. Regprof is useful for showing how well compilers make use of registers and for obtaining an indication of the susceptibility of application programs...

Briefs : Software
Real-Time Desktop Manager

Real-time Desktop Manager (RDM) is a computer program that manages displays and application programs. RDM was developed for use in connection with NASA’s remote manipulator system (RMS) group of flight controllers; it could also be used in chemical plants, laboratories, factories, hospitals, and other settings where...

Briefs : Electronics & Computers
FQPSK With an Outer Code for Greater Efficiency

A proposed method of FQPSK modulation and demodulation of a radio signal would incorporate any of a number of relatively simple (short-constraintlength) outer codes. By affording significant coding gains even when using a reduced-complexity (and thus suboptimal) FQPSK receiver, this method would...

Briefs : Electronics & Computers
Noncontact Scanning Surface Profilometers

A class of optoelectronic noncontact computer-controlled scanning surface profilometers is undergoing development for use in automated or semiautomated in- spection of nominally flat surfaces. When fully developed, these profilometers would generate three-dimensional maps of the scanned surfaces for...

Briefs : Electronics & Computers
Intuitive Control System for a Dexterous Robot

The Full Immersion Telepresence Testbed (FITT) is an experimental anthropomorphic-robot remote-control system that is so named because it gives a human control operator some of the sensations of the remote environment as though the operator were in that environment in place of the robot. In...

Briefs : Information Technology
Initialized Fractional Calculus

The fractional calculus (which admits of integrals and derivatives of non-integer order) dates back almost to the origin of the better-known ordinary (integer-order) calculus, but thus far has been treated more as a mathematical curiosity than as a scientific and engineering tool. Increasingly many physical...

Briefs : Electronics & Computers
Ultrasonic System Tracks Body Movements in Three Dimensions

A system based on ultrasonic sensors has been developed as a means of tracking moving objects with centimeter accuracy. The system is intended especially for tracking pertinent parts of the body of a human subject engaged in control of a remote anthropomorphic robot or immersed in a...

Briefs : Mechanical & Fluid Systems
Cylindrical Shape-Memory Rotary/Linear Actuator

A compact actuator generates rotary or linear motion with a large torque or force, respectively. The original version of this actuator is designed to pull a wedge that, until pulled, prevents retraction of the proposed extended nose landing gear of the space shuttle. The original version is also...

Briefs : Software
Program Finds Target-Chemical Signals in Multisensor Outputs

A computer program deconvolves the digitized outputs of multiple chemical sensors in an array to extract indications of the identities and con- centrations of target chemicals (which could be individual compounds or specified mixtures of compounds). Chemical-sensor arrays — denoted,...

Briefs : Test & Measurement
Pressure-Application Device for Testing Pressure Sensors

A portable pressure-application device has been designed and built for use in testing and calibrating piezoelectric pressure transducers in the field. The device generates pressure pulses of known amplitude. A pressure pulse (in contra- distinction to a steady pressure) is needed because...

Briefs : Physical Sciences
Slab-Waveguide Interferometer for Sensing Ammonia in Wet Air

The figure depicts a single-arm, slabwave- guide interferometer that has been demonstrated to be useable as a means of sensing ammonia in wet air. The slabwaveguide portion of this device comprises a 2-μm-thick film of poly(methyl methacrylate) [PMMA] on a substrate of fused quartz....

Briefs : Software
Program Computes Outer-Space Heat-Sink Temperatures

TSCALC is a computer program that calculates the space sink temp- erature (TS), defined as the equilibrium temp- erature of a spacecraft heat-dissipation radiator or other object nominally isolated except for radiative exchange of heat with the Sun, or any star for which equilibrium...

Briefs : Materials
Ablative Coat Protects Against Brief, Intense Heating

An ablative composite coating has been developed to protect a steel substrate against a short-duration exposure to supersonic stream of hot gases and molten ceramic particles. In the original application, the short-duration hot, abrasive flow is resultant from the shuttle solid-fuel rocket...

Briefs : Materials
Insertion of Reactive Material for Treating Groundwater

An improved method of inserting reactive material in the ground for treating groundwater contaminated with chlorinated solvents has been devised. An older method involves the removal of a significant portion of soil overlying the treatment volume, and consequently the expensive off-site...

Briefs : Mechanical & Fluid Systems
Formation Alignment of Multiple Autonomous Vehicles

A table-top experiment on formation alignment of three air-levitated robotic vehicles has been performed to demonstrate the feasibility of a more general concept of controlling multiple robotic vehicles to make them move in specified positions and orientations with respect to each other. The...

Briefs : Mechanical & Fluid Systems
Microfabricated Flow Controllers and Pressure Regulators

Efforts are underway to develop microfabricated flow controllers and pressure regulators that contain as few discrete components as feasible and that are cheaper, more robust, and orders of magnitude smaller than are currently commercially available devices that have similar capabilities....

Briefs : Manufacturing & Prototyping
Growing Carbon Nanotubes Aligned With Patterns

A process has been proposed for growing carbon nanotubes aligned substantially parallel with the nominal planar surfaces of substrates and further aligned with patterns on the substrates. Prior to growth, the patterns would be formed by micromachining the substrates, which could be silicon or...

Briefs : Manufacturing & Prototyping
Process for Rapid Prototyping in Ceramic-Matrix Composites

The ceramic-composite advanced tow- placement (CCATP) process is a means of laying down continuous-fiber-reinforced, ceramic-matrix composite (CMC) materials in patterned layers to form objects that could have complex three-dimensional shapes. The CCATP process is a member of the growing...

Briefs : Manufacturing & Prototyping
Low-Temperature Thermocompressive Au-to-Au Diffusion Bonding

A technique of thermocompressive gold-to-gold diffusion bonding at relatively low temperature has been devised to provide stable, uniform, strong bonds between struc- tural components of microelectromechanical systems. The technique can also be used for vacuum sealing of microscopic...

Briefs : Physical Sciences
Aircraft Anti-Icing Heaters Made From Expanded Graphite

Improved electrical resistance heaters for preventing the accum- ulation of ice on aircraft surfaces are undergoing development. The primary intended market for these heaters is that of small single- and twin-engine airplanes and helicopters, most of which have not been equipped with...

Briefs : Physical Sciences
Regulating Pressure-Volume Control of a Gas Blanketing Liquid R-124

A system for storing and circulating a refrigerant liquid [R- 124 (chloro- tetrafluoroethane)] includes a reservoir and a subsystem that regulates the pressure of nitrogen gas in the head space of the reservoir. The purpose of the pressurization is to prevent cavitation in a...

Briefs : Physical Sciences
Improved Capacitive Quality Meter for a Two-Phase Fluid

A previously developed quality/flow meter has been redesigned to improve its performance as a device for mea- suring the quality (but not the flow) of two-phase (liquid + vapor) oxygen or nitrogen flowing in a pipe. As used in engineering disciplines concerned with two-phase flows,...

Briefs : Physical Sciences
Ellipsoidal Collecting Horns for Ultrasonic Leak Detectors

Ellipsoidal reflectors have been proposed as collecting horns for ultrasonic leak det- ectors. Exploiting the classical focusing characteristics of ellipsoids, these ref- lectors would facilitate and enhance the detection of leaks in situations in which it is possible to bring...

Briefs : Information Technology
Flash Automated Updating of Software in Multiple Computers

Program and data files in the Unified Control Modules (UCMs) of the Operational Television system at Kennedy Space Center are updated rapidly and automatically in a scheme that exploits unique features of the UCM design. Each UCM includes a VersaModule Eurocard (VME) chassis, in which...

Briefs : Information Technology
Algorithm Plans Motion of Robot With Limited Field of View

The RoverBug algorithm plans the motion of a robotic vehicle (rover) equipped with a CCD (charge-coupled device) camera or comparable sensor that has a limited field of view. The algorithm produces locally optimal (shortest-distance) paths across unbounded, previously unknown terrain;...

Briefs : Information Technology
Product Attributes Database

Product Attributes Database (PAD) is a computer program that enables a team of engineers, managers, and administrators involved in a product-development project to collaborate more effectively. PAD serves as a single, network-accessible repository for all essential parametric information (the data- base) that...

Briefs : Test & Measurement
Simulating the Structural Behavior of Laminated Glass

This report investigates the strength of archi- tectural laminated glass and the viability of its use for window glass in commercial buildings. Some researchers recommend that the structural behavior of laminated glass (typically consisting of two glass layers and a plasticized PVB [polyvinyl...

Briefs : Mechanical & Fluid Systems
Synchronizing Attitudes and Maneuvers of Multiple Spacecraft

A report discusses the problem of controlling the maneuvers of multiple spacecraft flying in formation and, more specifically, making the entire formation rotate about a given axis and synchronizing the rotations of the individual spacecraft with the rotation of the formation. Such...

Briefs : Materials
Lightweight Solar Sail for a Spacecraft Flying Near the Sun

A report proposes a high-temperature- resistant solar sail with an areal mass density less than 1 g/m2, for a spacecraft that would approach the Sun to within a distance of 0.2 astronomical unit (≈3 × 107 km). The sail would be made in multiple segments of a carbon...

Briefs : Mechanical & Fluid Systems
Mesoscopic Winch for Precise Extension and Retraction

A proposed lightweight, micromachined winch would have microscopic structural details and mesoscopic overall dimensions and would be capable of generating bidirectional macro- scopic motion (maximum cable extension or retraction ≈1 m) with submicron increments. Winches like this one could...

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

Hardware and decentralized-control algorithms have been developed during continued research on the sensors, the actuators, and the design and functional requirements for systems of multiple mobile robots cooperating in the performance of tightly coupled tasks — for example, grasping...

Briefs : Physical Sciences
Electrohydrodynamic Conduction Pumps

Electrohydrodynamic (EHD) conduction pumps have been investigated in theo- retical and experimental studies. In general, EHD pumps contain no moving parts. They generate pressure gradients and/or flows in dielectric liquids via any of a variety of inter- actions between (1) applied electric fields and (2)...

Briefs : Manufacturing & Prototyping
Process for Rapid Prototyping in Ceramic-Matrix Composites

The ceramic-composite advanced tow-placement (CCATP) process is a means of laying down continuous-fiber-reinforced, ceramic-matrix composite (CMC) materials in patterned layers to form objects that could have complex three-dimensional shapes. The CCATP process is a member of the growing...

Briefs : Photonics/Optics
Self-Aligning Fiber Couplers for Microsphere Resonators

Fiber-optic couplers for spherical, toroidal, and other, similarly shaped microscopic optical resonators that operate in whispering-gallery (WG) modes would be fabricated with integral alignment features, according to a proposal. These alignment features would facilitate coupling...

Briefs : Photonics/Optics
Spotlight Radiometer

A proposed radiometric instrument denoted the spotlight radiometer (SLR) would operate in a frequency band centered at ≈557 GHz and would scan in a conical or circular pattern. The SLR was conceived for use in obtaining spatially and spectrally resolved indications of CO and H2O molecules in the Martian...

Briefs : Photonics/Optics
Relatively Inexpensive Unobscured Large-Aperture Laser-Beam Expander

A design for an unobscured, large-aperture but otherwise compact laser-beam expander relies solely on spherical reflecting and refracting surfaces, yet provides a reasonably well corrected wavefront suitable for most applications. This design results from a tradeoff among...

Briefs : Photonics/Optics
General-Purpose Stereo Imaging Velocimetry

An improved and expanded method of stereo imaging velocimetry (SIV) for diagnosing three-dimensional flows of gases, liquids, and other fluids involves the use of standard charge-coupled-device cameras positioned orthogonally to each other. In addition to providing a full-field, quantitative,...

Briefs : Physical Sciences
Infrared Fiber-Optic Endoscope

A proposed infrared transmitting fiber-optic endoscope, which would partly resemble a visible-light fiber-optic endoscope, instrument could be used to perform thermal imaging in harsh environments and/or confined spaces in a variety of situations in aerospace, industrial, automotive, and medical settings.

Briefs : Photonics/Optics
Adjusting Polarization To Reduce Error in an Interferometer

An unconventional and highly effective technique has been devised to reduce cyclic errors that arise in the operation of a displacement-measuring heterodyne optical interferometer. The cyclic errors are attributable largely to undesired small exchanges of power between light beams that...

Briefs : Photonics/Optics
Fiber-Optic Probe Uses Evanescent Waves To Sense Biofilm

A compact instrument includes a fiber-optic probe that utilizes the evanescent-wave interaction to measure the accumulation of a biofilm. This instrument is a prototype of instruments that could be used to effect continuous monitoring and provide early warning of biofilms associated with...