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 : Information Technology
Predicting Rocket or Jet Noise in Real Time

A semi-empirical theoretical model and a C++ computer program that implements the model have been developed for use in predicting the noise generated by a rocket or jet engine. The computer program, entitled the Realtime Rocket and Jet Engine Noise Analysis and Prediction Software, is one of two main...

Briefs : Software
Computational Workbench for Multibody Dynamics

PyCraft is a computer program that provides an interactive, workbench-like computing environment for developing and testing algorithms for multibody dynamics. Examples of multibody dynamic systems amenable to analysis with the help of PyCraft include land vehicles, spacecraft, robots, and...

Briefs : Semiconductors & ICs
SiC Multi-Chip Power Modules as Power-System Building Blocks

The term “SiC MCPMs” (wherein “MCPM” signifies “multi-chip power module”) denotes electronic power-supply modules containing multiple silicon carbide power devices and silicon-on-insulator (SOI) control integrated-circuit chips. SiC MCPMs are being developed as building...

Briefs : Electronics & Computers
High-Power, High-Efficiency Ka-Band Space Traveling-Wave Tube

The L-3 Communications Model 999H traveling-wave tube (TWT) has been demonstrated to generate an output power of 144 W at 60-percent overall efficiency in continuous-wave operation over the frequency band from 31.8 to 32.3 GHz. The best TWT heretofore commercially available for...

Briefs : Electronics & Computers
Gratings and Random Reflectors for Near-Infrared PIN Diodes

Crossed diffraction gratings and random reflectors have been proposed as means to increase the quantum efficiencies of InGaAs/InP positive/intrinsic/ negative (PIN) diodes designed to operate as near-infrared photodetectors. The proposal is meant especially to apply to focal-plane...

Briefs : Electronics & Computers
Aerial Videography From Locally Launched Rockets

A method of quickly collecting digital imagery of ground areas from video cameras carried aboard locally launched rockets has been developed. The method can be used, for example, to record rare or episodic events or to gather image data to guide decisions regarding treatment of agricultural fields...

Briefs : Electronics & Computers
Optically Transparent Split-Ring Antennas for 1 to 10 GHz

Split-ring antennas made from optically transparent, electrically conductive films have been invented for applications in which there are requirements for compact antennas capable of operation over much or all of the frequency band from 1 to 10 GHz. Primary examples of such applications...

Briefs : Electronics & Computers
Power-Amplifier Module for 145 to 165 GHz
Figure 1. The Amplifier Is Packaged in a WR5 waveguide module, with electric-field-plane alumina probes to interface the chip to the waveguide, and bypass capacitors to suppress low-frequency oscillations. The module is compact and can easily be integrated into a test system or with wafer probes.

A...

Briefs : Electronics & Computers
Ice-Penetrating Robot for Scientific Exploration

The cryo-hydro integrated robotic penetrator system (CHIRPS) is a partially developed instrumentation system that includes a probe designed to deeply penetrate the Europan ice sheet in a search for signs of life. The CHIRPS could also be used on Earth for similar exploration of the polar ice caps...

Briefs : Software
Automated Design of Restraint Layer of an Inflatable Vessel

A Mathcad computer program largely automates the design and analysis of the restraint layer (the primary load-bearing layer) of an inflatable vessel that consists of one or more sections having cylindrical, toroidal, and/or spherical shape(s). A restraint layer typically comprises...

Briefs : Software
TMS for Instantiating a Knowledge Base With Incomplete Data

A computer program that belongs to the class known among software experts as output truth-maintenance systems (output TMSs) has been devised as one of a number of software tools for reducing the size of the knowledge base that must be searched during execution of...

Briefs : Software
Simulating Flights of Future Launch Vehicles and Spacecraft

Marshall Aerospace Vehicle Representation in C (MAVERIC) is a computer program for generic, low-to-high-fidelity simulation of the flight(s) of one or more launch vehicle(s) or spacecraft. MAVERIC is designed to accommodate multi-staged vehicles, powered serially or in parallel, with...

Briefs : Software
Control Code for Bearingless Switched-Reluctance Motor

A computer program has been devised for controlling a machine that is an integral combination of magnetic bearings and a switched-reluctance motor. The motor contains an eightpole stator and a hybrid rotor, which has both (1) a circular lamination stack for levitation and (2) a six-pole...

Briefs : Software
Machine Aided Indexing and the NASA Thesaurus

Machine Aided Indexing (MAI) is a Web-based application program for aiding the indexing of literature in the NASA Scientific and Technical Information (STI) Database. MAI was designed to be a convenient, fully interactive tool for determining the subject matter of documents and identifying keywords....

Briefs : Software
Arbitrating Control of Control and Display Units

The ARINC 739 Switch is a computer program that arbitrates control of two multi-function control and display units (MCDUs) between (1) a commercial flight-management computer (FMC) and (2) NASA software used in research on transport aircraft. (MCDUs are the primary interfaces between pilots and...

Briefs : Software
Web-Based Software for Managing Research

aeroCOMPASS is a software system, originally designed to aid in the management of wind tunnels at Langley Research Center, that could be adapted to provide similar aid to other enterprises in which research is performed in common laboratory facilities by users who may be geographically dispersed. Included...

Briefs : Software
Driver Code for Adaptive Optics

A special-purpose computer code for a deformable-mirror adaptive-optics control system transmits pixel-registered control from (1) a personal computer running software that generates the control data to (2) a circuit board with 128 digital-to-analog converters (DACs) that generate voltages to drive the...

Briefs : Materials
Ceramic Paste for Patching High-Temperature Insulation

A ceramic paste that can be applied relatively easily, either by itself or in combination with one or more layer(s) of high temperature ceramic fabrics, such as silicon carbide or zirconia, has been invented as a means of patching cracks or holes in the reinforced carbon-carbon forward...

Briefs : Materials
Protective Skins for Aerogel Monoliths

A method of imparting relatively hard protective outer skins to aerogel monoliths has been developed. Even more than aerogel beads, aerogel monoliths are attractive as thermal-insulation materials, but the commercial utilization of aerogel monoliths in thermal-insulation panels has been inhibited by their...

Briefs : Materials
Fabrication of Polyimide-Matrix/Carbon and Boron-Fiber Tape

The term "HYCARB" denotes a hybrid composite of polyimide matrices reinforced with carbon and boron fibers. HYCARB and an improved process for fabricating dry HYCARB tapes have been invented in a continuing effort to develop lightweight, strong composite materials for aerospace...

Briefs : Mechanical & Fluid Systems
Asymmetric Bulkheads for Cylindrical Pressure Vessels

Asymmetric bulkheads are proposed for the ends of vertically oriented cylindrical pressure vessels. These bulkheads, which would feature both convex and concave contours, would offer advantages over purely convex, purely concave, and flat bulkheads (see figure). Intended originally to be...

Briefs : Mechanical & Fluid Systems
Code Assesses Risks Posed by Meteoroids and Orbital Debris

BUMPER II version 1.92e is a computer code for assessing the risk of damage from impacts of micrometeoroids and orbital debris on the International Space Station (ISS), including those parts of the ISS covered by shielding that affords partial protection against such impacts. (Other...

Briefs : Mechanical & Fluid Systems
Self-Regulating Water-Separator System for Fuel Cells

A proposed system would perform multiple coordinated functions in regulating the pressure of the oxidant gas (usually, pure oxygen) flowing to a fuel-cell stack and in removing excess product water that is generated in the normal fuel-cell operation. The system could function in the presence...

Briefs : Manufacturing & Prototyping
Self-Advancing Step-Tap Drills

Self-advancing tool bits that are hybrids of drills and stepped taps make it possible to form threaded holes wider than about 1/2 in. (about 13 mm) without applying any more axial force than is necessary for forming narrower pilot holes. These self-advancing stepped-tap drills were invented for use by space-suited...

Briefs : Physical Sciences
Array of Bolometers for Submillimeter-Wavelength Operation

A feed-horn-coupled monolithic array of micromesh bolometers is undergoing development for use in a photometric camera. The array is designed for conducting astrophysical observations in a wavelength band centered at 350 μm. The bolometers are improved versions of previously developed...

Briefs : Physical Sciences
Delta-Doped CCDs as Detector Arrays in Mass Spectrometers

Delta-doped, back-illuminated charge-coupled devices (CCDs) are used as detector arrays in high-performance double- focusing miniature mass spectrometers of Mattauch-Herzog design (described below). The uses of delta-doped CCD detector arrays eliminates the need for microchannel plates...

Briefs : Physical Sciences
Arrays of Bundles of Carbon Nanotubes as Field Emitters

Experiments have shown that with suitable choices of critical dimensions, planar arrays of bundles of carbon nanotubes (see figure) can serve as high-current-density field emitter (cold-cathode) electron sources. Whereas some hot-cathode electron sources must be operated at supply...

Briefs : Mechanical & Fluid Systems
Staggering Inflation To Stabilize Attitude of a Solar Sail

A document presents computational simulation studies of a concept for stabilizing the attitude of a spacecraft during deployment of such structures as a solar sail or other structures supported by inflatable booms. Specifically, the solar sail considered in this paper is a square sail...

Briefs : Mechanical & Fluid Systems
Bare Conductive Tether for Decelerating a Spacecraft

A document describes a prototype of electrically conductive tethers to be used primarily to decelerate spacecraft and/or generate electric power for the spacecraft. Like prior such tethers, this tether is designed so that when it is deployed from a spacecraft in orbit, its motion across the...

Briefs : Physical Sciences
Flexible Skins Containing Integrated Sensors and Circuitry

Artificial sensor skins modeled partly in imitation of biological sensor skins are undergoing development. These sensor skins comprise flexible polymer substrates that contain and/or support dense one- and two-dimensional arrays of microscopic sensors and associated microelectronic...

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