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 : Robotics, Automation & Control
Device Assists Actuation of a Joint in a Pressure Suit

An electromechanical device implements a unique method of actuating a fabric joint in an inflatable structure  in particular, the joint in an astronaut's pressure suit. The method is based on the principle that power from an external source can be applied to a non-constant-volume joint in...

Briefs : Physical Sciences
EPRI of Distributions of Free Radicals in Polyimide Samples

A report describes experiments in which electron paramagnetic resonance imaging (EPRI) was used to determine one-dimensional spatial distributions of free radicals in two plate specimens of PMR-15 polyimide. One specimen had been postcured at a temperature of 315 °C in nitrogen, then...

Briefs : Software
On-Line System Provides Accurate Ephemeris and Related Data

The Horizons On-Line Ephemeris and Data System ("Horizons" for short) is a computer program that provides data on the locations, motions, and dynamical parameters of solar-system objects, including the Sun, nine planets, 61 natural satellites, more than 16,000 comets and asteroids, and...

Briefs : Information Technology
Strategies for Optimal Placement of Sensors and Actuators

A paper presents a survey of sensor- and actuator-placement problems from various applications that involve a wide range of engineering disciplines. "Smart" structures that contain sensors (e.g., microphones or strain sensors) and actuators (e.g., loudspeakers or piezoelectric actuators)...

Briefs : Physical Sciences
Temperature-Stable Magnetic Sector for Mass Spectrometer

A magnetic sector in a proposed miniature mass spectrometer would include (1) a permanent magnet made of a high-energy-product material, (2) a conventional ferromagnetic yoke, and (3) a small temperature-compensating magnetic shunt. In the absence of the temperature compensation, it would...

Briefs : Electronics & Computers
Improved Control of Charging Current for Ni/H Battery

In a proposed method of controlling the electric current supplied for charging a nickel/hydrogen battery, the rate of evolution of heat would be taken into account along with the electrical quantities (voltage, current, and/or charge as functions of time) that are traditionally taken into...

Briefs : Software
Software for Planning and Execution in an Autonomous System

A software system for planning and execution of actions by an autonomous spacecraft engaged in scientific exploration has been developed to satisfy requirements to (1) maintain positive resource margins and avoid short-sighted decisions in order to achieve long-term scientific and...

Briefs : Electronics & Computers
Fast Transient-Voltage Recorder

The figure schematically illustrates an instrument designed expressly for recording lightning-induced transient voltages on power and signal cables. The principal advantage of this instrument over previously available transient-voltage recorders is high speed, as explained below.

Briefs : Robotics, Automation & Control
Modifications of the Ventricular Assist Device

A report discusses some modifications of the ventricular assist device (VAD), which was described in "Small Implantable Pump Would Assist Circulation of Blood" (MSC-22424), NASA Tech Briefs, Vol. 20, No. 7 (July 1996), page 86. The VAD is a surgically implantable, miniature rotary pump designed to...

Briefs : Motion Control
Biomorphic Robot With Distributed Power

The biomorphic robot with distributed power (BIROD) is a prototype of a class of robots that will contain simple, reliable distributed actuators that will consume power from local sources - a design concept inspired in part by biological actuators like muscles in limbs. The BIROD concept stands in...

Briefs : Manufacturing & Prototyping
Heated Weights for Adhesive Bonding

Heated weights have been found to be useful in adhesive bonding of clips, doublers, and other small parts to lightweight structures and structural components (e.g., face-sheet/honeycomb-core sandwich panels). The heated weights provide both the heat needed to accelerate curing of the adhesive and the force...

Briefs : Electronics & Computers
Improved Lightning-Current Measurements on a Protective Wire

A test procedure has been devised to increase the accuracy with which lightning currents on a protective wire can be determined from raw current measurements. The procedure was conceived specifically for determining lightning currents on a steel cable used to protect the space shuttle...

Briefs : Software
Program Generates Maps From IFSAR Data

A computer program provides for automated generation of maps from data acquired via C-band interferometric synthetic-aperture radar (IFSAR). The program reads in height, radar-brightness, and correlation data generated by IFSAR processors and computes a series of image features to be used in classifying...

Briefs : Robotics, Automation & Control
Model X-33 Subscale Flight Research Program

A program of flight testing of an instrumented subscale model of the X-33 aerospace vehicle is underway. The objectives of this program are the following:

Briefs : Electronics & Computers
Low-Power, Moderate-Speed Serial Data Communication Link

A low-power serial data communication link has been designed to transmit data among subsystems of a spacecraft instrumentation system, at rates up to 5 × 105 bits per second. The design of the link is adaptable to other spacecraft systems and to terrestrial applications that...

Briefs : Motion Control
Fault-Tolerant Feedback System for Robot Control

A fault-tolerant feedback (FTF) system has been integrated into a robot control system to prevent robot-arm runaways that could be caused by failure of one or more transducers such as joint-position, torque, and motor-temperature sensors, or in associated wiring harness channels. The FTF system...

Briefs : Materials
Lightweight, Oxidation-Resistant CwSixOyBz Ceramics

Lightweight, monolithic ceramics that retain their shapes and strengths and resist oxidation at temperatures up to 1,200 °C have been invented. These ceramics are made of carbon, silicon, oxygen, and boron. These ceramics are made by (1) using a sol-gel process to infiltrate noncarbon...

Briefs : Mechanical & Fluid Systems
Shrouds Would Catch Debris From Disintegrating Machines

Kinetic-energy-absorbing shrouds have been proposed to protect nearby persons and equipment against high-speed debris ejected by disintegrating machines. Examples of machines that could eject high-speed debris include turbines and gyroscopes. The shrouds would be laminated composites of...

Briefs : Electronics & Computers
Active-Pixel-Sensor ICs With Photosites in Substrates

Focal-plane arrays of active-pixel sensors (photodetectors integrated with in-pixel readout transistors) would be designed and fabricated within the emerging technological discipline of silicon-on-insulator (SOI) complementary metal oxide/semiconductor (CMOS) integrated circuits (ICs),...

Briefs : Electronics & Computers
Frequency-Scanning Capaciflectors

Capacitive proximity sensors of this proposed type would be based on the capaciflector concept, with an extension of hardware and software designs to incorporate capabilities for scanning in frequency and analyzing the resulting capacitance-vs.-frequency data. The proposed frequency-scanning sensors would...

Briefs : Electronics & Computers
Evolvable Multiagent Approach to Spacecraft Communication

A paper presents the concept of a system for autonomous communication among multiple satellites and other spacecraft. The design of the system would be based on an evolvable architecture of multiple intelligent agents (that is, artificial-intelligence constructs implemented in software...

Briefs : Electronics & Computers
Acoustic Sensor to Monitor Physiology and Voice

The Army Research Laboratory (ARL) has developed a new method of measuring human physiological stress parameters. This consists of an acoustic sensor positioned inside a fluid-filled bladder in contact with the body. Packaging the sensor in this manner minimizes outside environmental...

Briefs : Electronics & Computers
Integrated Infrared- and Visible-Image Sensors

Integrated circuits capable of sensing both infrared and visible images have been proposed. Until now, the usual practice for simultaneous imaging at both infrared and visible wavelengths in the same camera has involved splitting of the optical path into an infrared and a visible branch, each...

Briefs : Electronics & Computers
GaN-Based Linear Array of Ultraviolet Detectors

A recently developed gallium nitride-based linear array of ultraviolet detectors is blind to most of the visible spectrum, with a cutoff wavelength of 370 nm. This device is a prototype of GaN detector arrays for ultraviolet-light imaging in the presence of significant visible radiation, without...

Briefs : Mechanical & Fluid Systems
Deflection of Stretched Circular Membrane Under Pressure

Equations have been derived to describe the deflection of a circular membrane under both in-plane and transverse loads. More specifically, the equations describe the radial (in-plane) and perpendicular-to-the-plane deflections for the case of a circular membrane that has been stretched at...

Briefs : Software
Program for Designing Multiple-Reflector Antenna Systems

Millimeter-Wave Optics Design Tool (MOD Tool) is a computer program for analyzing and designing multiple-reflector antenna systems that operate at microwave and millimeter wavelengths. MOD Tool is intended for use in conjunction with a computer-aided-design (CAD) program along with other...

Briefs : Materials
Electrodialysis To Remove Ammonium Ions From Wastewater

Electrodialysis has been shown to be an effective means for removing ammonium ions from wastewater without use of consumable chemicals and without adding other substances to the treated water. Provided that continuing efforts to develop efficient electrodialysis equipment prove successful,...

Briefs : Mechanical & Fluid Systems
Hybrisol Rocket Engines

"Hybrisol" denotes a proposed rocket engine that would contain hybrid and solid-propellant parts within a single combustion chamber. ["Hybrid" as used here denotes a type of rocket engine in which a solid fuel is burned by use of a liquid or gaseous oxidizer and the flow of the oxidizer can be throttled to control the...

Briefs : Mechanical & Fluid Systems
Making Liquid Air in Small, Economical Quantities

A mixing apparatus combines liquid oxygen and liquid nitrogen to make liquid air in small, convenient quantities. Heretofore, equipment used to make liquid air by mixing was incapable of making batches smaller than 600 gallons (2,300 L). The present mixing apparatus produces liquid air on demand...

Briefs : Physical Sciences
Digitally Tunable Color Filters and Beam Scanners

Color-filtering and beam-scanning devices based on electro-optical switching of internal-reflection states have been proposed for use in display and measurement applications. Associated digital circuits would apply electronic control signals to spatial segments of these devices to obtain...