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 : Mechanical & Fluid Systems
Controllable Curved Mirrors Made From Single-Layer EAP Films

A document proposes that light-weight, deployable, large- aperture, controllable curved mirrors made of reflectively coated thin electroactive-polymer (EAP) films be developed for use in spaceborne microwave and optical systems. In these mirrors, the EAP films would serve as both...

Briefs : Manufacturing & Prototyping
Thermally Conductive Metal-Tube/Carbon-Composite Joints

An improved method of fabricating joints between metal and carbon-fiber-based composite materials in lightweight radiators and heat sinks has been devised. Carbon-fiber-based composite materials have been used in such heat-transfer devices because they offer a combination of high thermal...

Briefs : Photonics/Optics
Discrete Wavelength-Locked External Cavity Laser

A prototype improved external cavity laser (ECL) was demonstrated in the second phase of a continuing effort to develop wavelength-agile lasers for fiber-optic communications and trace-gas-sensing applications. This laser is designed to offer next-generation performance for incorporation into...

Briefs : Photonics/Optics
Optoelectronic Instrument Monitors pH in a Culture Medium

An optoelectronic instrument monitors the pH of an aqueous cell-culture medium in a perfused rotating-wall-vessel bioreactor. The instrument is designed to satisfy the following requirements:

Briefs : Manufacturing & Prototyping
Heat Control via Torque

In a proposed advance in friction stir welding, the torque exerted on the workpiece by the friction stir pin would be measured and controlled in an effort to measure and control the total heat input to the workpiece. The total heat input to the workpiece is an important parameter of any welding process (fusion or...

Briefs : Manufacturing & Prototyping
Setup for Visual Observation of Carbon-Nanotube Arc Process

A simple optical setup has been devised to enable safe viewing of the arc and measurement of the interelectrode gap in a process in which carbon nanotubes are produced in an arc between a catalyst-filled carbon anode and a graphite cathode. This setup can be used for visually guided...

Briefs : Manufacturing & Prototyping
Manufacturing High-Quality Carbon Nanotubes at Lower Cost

A modified electric-arc welding process has been developed for manufacturing high-quality batches of carbon nanotubes at relatively low cost. Unlike in some other processes for making carbon nanotubes, metal catalysts are not used and, consequently, it is not necessary to perform...

Briefs : Medical
Using an Ultrasonic Instrument to Size Extravascular Bubbles

In an ongoing development project, microscopic bubbles in extravascular tissue in a human body will be detected by use of an enhanced version of the apparatus described in "Ultrasonic Bubble- Sizing Instrument" (MSC-22980), NASA Tech Briefs, Vol.24, No.10 (October 2000), page 62. To...

Briefs : Medical
Transplanting Retinal Cells Using Bucky Paper for Support

A novel treatment for retinal degenerative disorders involving transplantation of cells into the eye is currently under development at NASA Ames Research Center and Stanford University School of Medicine. The technique uses bucky paper as a support material for retinal pigment epithelial...

Briefs : Electronics & Computers
Data Relay Board With Protocol for High-Speed, Free-Space Optical Communications

In a free-space optical communication system, the mitigation of transient out-ages through the incorporation of error-control methods is of particular concern, the outages being caused by scintillation fades and obscurants. The focus of this innovative technology is...

Briefs : Electronics & Computers
Analyzing Spacecraft Telecommunication Systems

Multi-Mission Telecom Analysis Tool (MMTAT) is a C-language computer program for analyzing proposed spacecraft telecommunication systems. MMTAT utilizes parameterized input and computational models that can be run on standard desktop computers to perform fast and accurate analyses of...

Briefs : Electronics & Computers
FPGA-Based, Self-Checking, Fault-Tolerant Computers

A proposed computer architecture would exploit the capabilities of commercially available field-programmable gate arrays (FPGAs) to enable computers to detect and recover from bit errors. The main purpose of the proposed architecture is to enable fault-tolerant computing in the presence of...

Briefs : Electronics & Computers
Ultralow-Power Digital Correlator for Microwave Polarimetry

A recently developed high-speed digital correlator is especially well suited for processing readings of a passive microwave polarimeter. This circuit computes the auto-correlations of, and the cross-correlations among, data in four digital input streams representing samples of in-phase...

Briefs : Electronics & Computers
Grounding Headphones for Protection Against ESD

A simple alternative technique has been devised protecting delicate equipment against electrostatic discharge (ESD) in settings in which workers wear communication headsets. In the original setting in which the technique was devised, the workers who wear the headsets also wear anti-ESD grounding...

Briefs : Electronics & Computers
Highly Efficient Vector-Inversion Pulse Generators

Improved transmission-line pulse generators of the vector-inversion type are being developed as lightweight sources of pulsed high voltage for diverse applications, including spacecraft thrusters, portable x-ray imaging systems, impulse radar systems, and corona-discharge systems for sterilizing...

Briefs : Electronics & Computers
Lightweight Stacks of Direct Methanol Fuel Cells

An improved design concept for direct methanol fuel cells makes it possible to construct fuel-cell stacks that can weigh as little as one-third as much as do conventional bipolar fuel-cell stacks of equal power. The structural-support components of the improved cells and stacks can be made of...

Briefs : Physical Sciences
Working Fluids for Increasing Capacities of Heat Pipes

A theoretical and experimental investigation has shown that the capacities of heat pipes can be increased through suitable reformulation of their working fluids. The surface tensions of all of the working fluids heretofore used in heat pipes decrease with temperature. As explained in more...

Briefs : Physical Sciences
On-the-Fly Mapping for Calibrating Directional Antennas

An improved method of calibrating a large directional radio antenna of the type used in deep-space communication and radio astronomy has been developed. This method involves a raster-scanning-and-measurement technique denoted on-the-fly (OTF) mapping, applied in consideration of the results...

Briefs : Physical Sciences
Coronagraphic Notch Filter for Raman Spectroscopy

A modified coronagraph has been proposed as a prototype of improved notch filters in Raman spectrometers. Corona-graphic notch filters could offer alternatives to both (1) the large and expensive double or triple monochromators in older Raman spectrometers and (2) holographic notch filters, which...

Briefs : Physical Sciences
Preparing and Analyzing Iced Airfoils

SmaggIce version 1.2 is a computer program for preparing and analyzing iced airfoils.It includes interactive tools for

measuring ice-shape characteristics, controlled smoothing of ice shapes, curve discretization, generation of artificial ice shapes,and detection and correction of input errors.
Briefs : Physical Sciences
Rapid Chemometric Filtering of Spectral Data

A method of rapid, programmable filtering of spectral transmittance, reflectance, or fluorescence data to measure the concentrations of chemical species has been proposed. By "programmable" is meant that a variety of spectral analyses can readily be performed and modified in software,...

Briefs : Mechanical & Fluid Systems
Centrifugal Adsorption System

The centrifugal adsorption cartridge system (CACS) is an apparatus that recovers one or more bioproduct(s) from a dilute aqueous solution or suspension flowing from a bioreactor. The CACS can be used both on Earth in unit gravity and in space in low gravity. The CACS can be connected downstream from the bioreactor;...

Briefs : Mechanical & Fluid Systems
Ultrasonic Apparatus for Pulverizing Brittle Material

The figure depicts an apparatus that pulverizes brittle material by means of a combination of ultrasonic and sonic vibration, hammering, and abrasion. The basic design of the apparatus could be specialized to be a portable version for use by a geologist in collecting powdered rock samples for...

Briefs : Mechanical & Fluid Systems
Liquid-Metal-Fed Pulsed Plasma Thrusters

A short document proposes liquid- metal- fed pulsed plasma thrusters for small spacecraft. The propellant liquid for such a thruster would be a low- melting- temperature metal that would be stored molten in an unpressurized, heated reservoir and would be pumped to the thruster by a magneto- hydrodynamic...

Briefs : Mechanical & Fluid Systems
Attitude Control for a Solar-Sail Spacecraft

A report describes the personal radiation protection system (PRPS), which has been invented for use on the International Space Station and other spacecraft. The PRPS comprises walls that can be erected inside spacecraft, where and when needed, to reduce the amount of radiation to which personnel are...

Briefs : Information Technology
Determining Sizes of Particles in a Flow From DPIV Data

A proposed method of measuring the size of particles entrained in a flow of a liquid or gas would involve utilization of data from digital particle-image velocimetry (DPIV) of the flow. That is to say, with proper design and operation of a DPIV system, the DPIV data could be processed...

Briefs : Information Technology
Faster Processing for Inverting GPS Occultation Data

A document outlines a computational method that can be incorporated into two prior methods used to invert Global Positioning System (GPS) occultation data [signal data acquired by a low-Earth-orbiting satellite as either this or the GPS satellite rises above or falls below the horizon] to...

Briefs : Information Technology
Framework for Development of Object-Oriented Software

The Real-Time Control (RTC) Application Framework is a high-level software framework written in C++ that supports the rapid design and implementation of object-oriented application programs. This framework provides built-in functionality that solves common software development problems within...

Briefs : Information Technology
Collaborative Planning of Robotic Exploration

The Science Activity Planner (SAP) software system includes an uplink-planning component, which enables collaborative planning of activities to be undertaken by an exploratory robot on a remote planet or on Earth. Included in the uplink-planning component is the SAP-Uplink Browser, which enables...

Briefs : Information Technology
Tools for Administration of a UNIX-Based Network

Several computer programs have been developed to enable efficient administration of a large, heterogeneous, UNIX-based computing and communication network that includes a variety of computers connected to a variety of sub-networks. One program provides secure software tools for administrators to...

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