January 2004

Briefs : Medical
Multisensor Instrument for Real-Time Biological Monitoring

The figure schematically depicts an instrumentation system, called a "fiber optic-based integration system" (FOBIS), that is undergoing development to enable real-time monitoring of fluid cell cultures, bioprocess flows, and the like. The FOBIS design combines a micro flow cytometer...

Briefs : Electronics & Computers
Backed Bending Actuator

Bending actuators of a proposed type would partly resemble ordinary bending actuators, but would include simple additional components that would render them capable of exerting large forces at small displacements. Like an ordinary bending actuator, an actuator according to the proposal would include a thin rectangular...

Briefs : Electronics & Computers
Compact Optoelectronic Compass

A compact optoelectronic sensor unit measures the apparent motion of the Sun across the sky. The data acquired by this chip are processed in an external processor to estimate the relative orientation of the axis of rotation of the Earth. Hence, the combination of this chip and the external processor finds the...

Briefs : Electronics & Computers
Micro Sun Sensor for Spacecraft

A report describes the development of a compact micro Sun sensor for use as a part of the attitude determination subsystem aboard future miniature spacecraft and planetary robotic vehicles.

Briefs : Electronics & Computers
Adaptive Fault-Tolerant Computer Capable of Error-Free Operation During Solar Flares

Space missions requiring the highest upset rate immunity typically turn to rad-hard system designs. Unfortunately, these systems are many generations behind commercial performance, and their upset immunity is becoming less effective with the increasing number of...

Briefs : Electronics & Computers
Passive IFF: Autonomous Nonintrusive Rapid Identification of Friendly Assets

A proposed optoelectronic instrument would identify targets rapidly, without need to radiate an interrogating signal, apply identifying marks to the targets, or equip the targets with transponders. The instrument was conceived as an identification, friend or foe (IFF)...

Briefs : Electronics & Computers
Finned-Ladder Slow-Wave Circuit for a TWT

A finned-ladder structure has been invented in an effort to improve the design of the slow-wave circuit of a traveling-wave tube (TWT). The point of departure for the design effort was a prototype TWT that contains a ring-plane slow-wave circuit (see Figure 1). The design effort was a response to the...

Briefs : Electronics & Computers
Directional Radio-Frequency Identification Tag Reader

A directional radio-frequency identification (RFID) tag reader has been designed to facilitate finding a specific object among many objects in a crowded room. The device could be an adjunct to an electronic inventory system that tracks RFID-tagged objects as they move through reader-equipped...

Briefs : Physical Sciences
Controllable Sonar Lenses and Prisms Based on ERFs

Sonar-beam-steering devices of the proposed type would contain no moving parts and would be considerably smaller and less power-hungry, relative to conventional multiple-beam sonar arrays. The proposed devices are under consideration for installation on future small autonomous underwater...

Briefs : Physical Sciences
The StarLight Space Interferometer

Two papers describe the StarLight space interferometer — a Michelson interferometer that would be implemented by two spacecraft flying in formation. The StarLight formation flying interferometer project has been testing and demonstrating engineering concepts for a new generation of space interferometers that...

Briefs : Physical Sciences
Champagne Heat Pump

The term "champagne heat pump" denotes a developmental heat pump that exploits a cycle of absorption and desorption of carbon dioxide in an alcohol or other organic liquid. Whereas most heat pumps in common use in the United States are energized by mechanical compression, the champagne heat pump is energized by heating.

Briefs : Physical Sciences
Freeze-Tolerant Condensers

Two condensers designed for use in dissipating heat carried by working fluids feature two-phase, self-adjusting configurations such that their working lengths automatically vary to suit their input power levels and/or heat-sink temperatures. A key advantage of these condensers is that they can function even if the...

Briefs : Physical Sciences
Sensor for Monitoring Nanodevice-Fabrication Plasmas

The term "plasma process diagnostics" (PPD) refers to a spectroscopic technique and sensing hardware that have been proposed for monitoring plasma processes used to fabricate electronic devices that feature sizes as small as several nanometers. Nanometer dimensions are characteristic of the...

Briefs : Physical Sciences
Electrokinetic In Situ Treatment of Metal-Contaminated Soil

An electrokinetic technique has been developed as a means of in situ remediation of soils, sludges, and sediments that are contaminated with heavy metals. Examples of common metal contaminants that can be removed by this technique include cadmium, chromium, zinc, lead, mercury, and...

Briefs : Mechanical & Fluid Systems
Miniature Blimps for Surveillance and Collection of Samples

Miniature blimps are under development as robots for use in exploring the thick, cold, nitrogen atmosphere of Saturn's moon, Titan. Similar blimps can also be used for surveillance and collection of biochemical samples in buildings, caves, subways, and other, similar structures on...

Briefs : Mechanical & Fluid Systems
Hybrid Automotive Engine Using Ethanol-Burning Miller Cycle

A proposed hybrid (internal-combustion/ electric) automotive engine system would include as its internal-combustion subsystem, a modified Miller-cycle engine with regenerative air preheating and with autoignition like that of a Diesel engine. The fuel would be ethanol and would be...

Briefs : Information Technology
Serial-Turbo-Trellis-Coded Modulation With Rate-1 Inner Code

Serially concatenated turbo codes have been proposed to satisfy requirements for low bit- and word-error rates and for low (in comparison with related previous codes) complexity of coding and decoding algorithms and thus low complexity of coding and decoding circuitry. These codes are...

Briefs : Information Technology
Enhanced Software for Scheduling Space-Shuttle Processing

The Ground Processing Scheduling System (GPSS) computer program is used to develop streamlined schedules for the inspection, repair, and refurbishment of space shuttles at Kennedy Space Center. A scheduling computer program is needed because space-shuttle processing is complex and it is...

Briefs : Information Technology
Bayesian-Augmented Identification of Stars in a Narrow View

An algorithm for the identification of stars from a charge-coupled-device (CCD) image of a star field has been extended for use with narrower field-of-view images. Previously, the algorithm had been shown to be effective at a field of view of 8°. This work augments the earlier...

Briefs : Materials
Making Carbon-Nanotube Arrays Using Block Polymers: Part II

Some changes have been incorporated into a proposed method of manufacturing regular arrays of precisely sized, shaped, positioned, and oriented carbon nanotubes. Such arrays could be useful as mechanical resonators for signal filters and oscillators, and as electrophoretic filters for...

Briefs : Software
Software for Checking Statecharts

HiVy is a software tool set that enables verification through model checking of designs represented as finite-state machines or statecharts. HiVy provides automated translation of (1) statecharts created by use of the MathWorks Stateflow® program to (2) Promela, the input language of the Spin model checker,...

Briefs : Software
Program Predicts Broadband Noise From a Turbofan Engine

Broadband Fan Noise Prediction System (BFaNS) is a computer program that, as its name indicates, predicts the broadband noise generated by the fan stage of a turbofan engine. This noise is the sum of (1) turbulent- inflow noise, which is caused by turbulence impinging on leading edges of...

Briefs : Software
Protocol for Delay-Tolerant Data-Communication Network

As its name partly indicates, the Delay-Tolerant Networking (DTN) Bundle Protocol is a protocol for delay-tolerant transmission of data via communication networks. This protocol was conceived as a result of studies of how to adapt Internet protocols so that Internet-like services could be...

Briefs : Software
Software Implements a Space-Mission File-Transfer Protocol

CFDP is a computer program that implements the CCSDS (Consultative Committee for Space Data Systems) File Delivery Protocol, which is an international standard for automatic, reliable transfers of files of data between locations on Earth and in outer space. CFDP administers concurrent...

Briefs : Mechanical & Fluid Systems
Modular Rake of Pitot Probes

The figure presents selected views of a modular rake of 17 pitot probes for measuring both transient and steady-state pressures in a supersonic wind tunnel. In addition to pitot tubes visible in the figure, the probe modules contain (1) high-frequency dynamic-pressure transducers connected through wires to remote...

Briefs : Mechanical & Fluid Systems
Spacecraft Orbits for Earth/Mars-Lander Radio Relay

A report discusses a network of spacecraft, in orbit around Mars, used to relay radio communications between Earth stations and mobile exploratory robots (rovers) as well as stationary scientific instruments that have been landed on the Mars surface. The relay spacecraft include two already in...

Briefs : Photonics/Optics
Fabricating Blazed Diffraction Gratings by X-Ray Lithography

Gray-scale x-ray lithography is undergoing development as a technique for fabricating blazed diffraction gratings. As such, gray-scale x-ray lithography now complements such other grating-fabrication techniques as mechanical ruling, holography, ion etching, laser ablation, laser...

Briefs : Photonics/Optics
Stroboscope Controller for Imaging Helicopter Rotors

A versatile electronic timing-and-control unit, denoted a rotorcraft strobe controller, has been developed for use in controlling stroboscopes, lasers, video cameras, and other instruments for capturing still images of rotating machine parts - especially helicopter rotors. This unit is...

Briefs : Mechanical & Fluid Systems
Multiphysics Analysis Helps Simulate Diesel Engine Cylinder Head

As part of a Small Business Innovation Research (SBIR) grant from TACOM (Tank-Automotive & Armaments Command) - a division of the U.S. Army -Adiabatics used multiphysics finite element analysis (FEA) software from ALGOR to study the thermal and structural behavior of a cylinder...

Briefs : Photonics/Optics
Measuring Gravitation Using Polarization Spectroscopy

A proposed method of measuring gravitational acceleration would involve the application of polarization spectroscopy to an ultracold, vertically moving cloud of atoms (an atomic fountain). A related proposed method involving measurements of absorption of light pulses like those used in...

Briefs : Photonics/Optics
Integrated Solar-Energy-Harvesting and -Storage Device
Integrated Solar-Energy-Harvesting and -Storage Device

A modular, integrated, completely solid-state system designed to harvest and store solar energy is under development. Called the "power tile," the hybrid device consists of a...

Integrated Solar-Energy-Harvesting and -Storage Device
Briefs : Photonics/Optics
Event-Driven Random-Access-Windowing CCD Imaging System
Event-Driven Random-Access-Windowing CCD Imaging System

A charge-coupled-device (CCD) based high-speed imaging system, called a real-time, event-driven (RARE) camera, is undergoing development. This camera is capable of readout from multiple...

Event-Driven Random-Access-Windowing CCD Imaging System
Briefs : Photonics/Optics
Laser Direct Structuring and Liquid Crystal Polymer Simplify Circuit Miniaturization
Laser Direct Structuring and Liquid Crystal Polymer Simplify Circuit Miniaturization

There has long been a desire to deposit conductive paths directly on molded plastic structures, combining the electrical and mechanical functions in one...

Laser Direct Structuring and Liquid Crystal Polymer Simplify Circuit Miniaturization
Briefs : Mechanical & Fluid Systems
Preloading To Accelerate Slow-Crack-Growth Testing
Preloading To Accelerate Slow-Crack-Growth Testing
Preloading To Accelerate Slow-Crack-Growth Testing
Briefs : Mechanical & Fluid Systems
Self-Inflatable/Self-Rigidizable Reflectarray Antenna

A report describes recent progress in a continuing effort to develop large reflectarray antennas to be deployed in space. Major underlying concepts were reported in two prior NASA Tech Briefs articles: "Inflatable Reflectarray Antennas" (NPO-20433), Vol. 23, No. 10 (October 1999), page 50 and...

Briefs : Photonics/Optics
Light Diffusion Filter Materials Enhance Flat Screen Displays
Light Diffusion Filter Materials Enhance Flat Screen Displays

Specially formulated diffusion filter materials have successfully optimized the legibility of miniature display viewing areas, providing brighter and more enhanced images for a...

Light Diffusion Filter Materials Enhance Flat Screen Displays