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 : Physical Sciences
Nonlinear FEA Analysis of Filament-Wound Composite Container Tanks

Filament-wound composites are replacing metals as the material of choice for tanks to hold liquids and gases. The composites have a high strength-to- weight ratio, making them ideal for use in aerospace and commercial ground transport. Also, the automated winding process is less...

Briefs : Information Technology
Finding Minimum-Power Broadcast Trees for Wireless Networks

Some algorithms have been devised for use in a method of constructing tree graphs that represent connections among the nodes of a wireless ommunication network. These algorithms provide for determining the viability of any given candidate connection tree and for generating an initial...

Briefs : Information Technology
Hexagonal Pixels and Indexing Scheme for Binary Images

A scheme for resampling binaryimage data from a rectangular grid to a regular hexagonal grid and an associated tree - structured pixel - indexing scheme keyed to the level of resolution have been devised. This scheme could be utilized in conjunction with appropriate image - data - processing...

Briefs : Software
Simulation of Hyperspectral Images

A software package generates simulated hyperspectral imagery for use in validating algorithms that generate estimates of Earth- surface spectral reflectance from hyperspectral images acquired by airborne and spaceborne instruments.

This software is based on a direct simulation Monte Carlo approach for...

Briefs : Software
PVM Wrapper

PVM Wrapper is a software library that makes it possible for code that utilizes the Parallel Virtual Machine (PVM) software library to run using the message-passing interface (MPI) software library, without needing to rewrite the entire code. PVM and MPI are the two most common software libraries used for applications that involve...

Briefs : Software
Algorithm for Controlling a Centrifugal Compressor

Algorithm for Controlling a Centrifugal Compressor An algorithm has been developed for controlling a centrifugal compressor that serves as the prime mover in a heatpump system. Experimental studies have shown that the operating conditions for maximum compressor efficiency are close to the...

Briefs : Mechanical & Fluid Systems
Double-Acting, Locking Carabiners

A proposed design for carabiners (tether hooks used in mountaineering, rock climbing, and rescue) is intended to make it possible to operate these devices even while wearing thick gloves. According to the proposal, the gate of a carabiner would be capable of swinging either toward or away from the hook body,...

Briefs : Motion Control
Position Sensor Integral With a Linear Actuator
Position Sensor Integral With a Linear Actuator

A noncontact position sensor has been designed for use with a specific two-dimensional linear electromagnetic actuator. To minimize the bulk and weight added by the sensor, the sensor has been...

Position Sensor Integral With a Linear Actuator
Briefs : Photonics/Optics
Fabrication of Robust, Flat, Thinned, UVImaging CCDs

An improved process that includes a high-temperature bonding subprocess has been developed to enable the fabrication of robust, flat, silicon-based charge-coupled devices (CCDs) for imaging in ultraviolet (UV) light and/or for detecting low energy charged particles. The CCDs in question are...

Briefs : Motion Control
Improved Electromagnetic Brake
Improved Electromagnetic Brake

A proposed design for an electromagnetic brake would increase the reliability while reducing the number of parts and the weight, relative to a prior commercially available electromagnetic brake. The reductions...

Improved Electromagnetic Brake
Briefs : Photonics/Optics
Semiconductor Lasers Containing Quantum Wells in Junctions

In a recent improvement upon InxGa1- xAs/InP semiconductor lasers of the bipolar cascade type, quantum wells are added to Esaki tunnel junctions, which are standard parts of such lasers. The energy depths and the geometric locations and thicknesses of the wells are tailored to exploit...

Briefs : Photonics/Optics
Improved Refractometer for Measuring Temperatures of Drops

The Dual Rainbow refractometer is an enhanced version of the Rainbow refractometer, which is added to, and extends the capabilities of, a phase Doppler particle analyzer (PDPA). A PDPA utilizes pairs of laser beams to measure individual components of velocity and sizes of drops in a...

Briefs : Photonics/Optics
Phytoplankton-Fluorescence-Lifetime Vertical Profiler

A battery-operated optoelectronic instrument is designed to be lowered into the ocean to measure the intensity and lifetime of fluorescence of chlorophyll A in marine phytoplankton as a function of depth from 0 to 300 m. Fluorescence lifetimes are especially useful as robust measures of...

Briefs : Motion Control
Active Suppression of Instabilities in Engine Combustors
Active Suppression of Instabilities in Engine Combustors

A method of feedback control has been proposed as a means of suppressing thermo-acoustic instabilities in a liquid- fueled combustor of a type used in an aircraft engine. The basic...

Active Suppression of Instabilities in Engine Combustors
Briefs : Photonics/Optics
Whispering-Gallery-Mode Tunable Narrow-Band-Pass Filter

An experimental tunable, narrowband-pass electro-optical filter is based on a whispering-gallery resonator. This device is a prototype of tunable filters needed for the further development of reconfigurable networking wavelength division multiplexers and communication systems that utilize...

Briefs : Mechanical & Fluid Systems
Flow Straightener for a Rotating-Drum Liquid Separator

A flow straightener has been incorporated into a rotary liquid separator that originally comprised an inlet tube, a shroud plate, an impeller, an inner drum, an outer drum, a housing, a pitot tube, and a hollow shaft motor. As a consequence of the original geometry of the impeller, shroud,...

Briefs : Mechanical & Fluid Systems
Hybrid Inflatable Pressure Vessel
Hybrid Inflatable Pressure Vessel

Figure 1 shows a prototype of a large pressure vessel under development for eventual use as a habitable module for long spaceflight (e.g., for transporting humans to Mars). The vessel is a hybrid that...

Hybrid Inflatable Pressure Vessel
Briefs : Physical Sciences
Solution-Assisted Optical Contacting

A modified version of a conventional optical-contact procedure has been found to facilitate alignment of optical components. The optical-contact procedure (called simply "optical contacting" in the art) is a standard means of bonding two highly polished and cleaned glass optical components without using...

Briefs : Medical
Finite Element Analysis Used to Examine the Healing of Animal Bones

When a dog or cat breaks a bone, veterinarians often mend the fracture with a combination of stabilization devices called intra-medullary (IM) pins and external skeletal fixators (ESFs), a technique that is employed daily across the U.S. Research conducted at the University of...

Briefs : Electronics & Computers
Advanced Signal Conditioners for Data-Acquisition Systems

Signal conditioners embodying advanced concepts in analog and digital electronic circuitry and software have been developed for use in data-acquisition systems that are required to be compact and lightweight, to utilize electric energy efficiently, and to operate with high reliability,...

Briefs : Electronics & Computers
Downlink Data Multiplexer

A multiplexer/demultiplexer system has been developed to enable the transmission, over a single channel, of four data streams generated by a variety of sources at different (including variable) bit rates. In the original intended application, replicas of this multiplexer/demultiplexer system would be incorporated into...

Briefs : Electronics & Computers
Parallel-Processing Equalizers for Multi-Gbps Communications

Architectures have been proposed for the design of frequency-domain least-mean-square complex equalizers that would be integral parts of parallel-processing digital receivers of multigigahertz radio signals and other quadrature - phase - shift - keying (QPSK) or 16 - quadrature -...

Briefs : Electronics & Computers
AIN-Based Packaging for SiC High-Temperature Electronics

Packaging made primarily of aluminum nitride has been developed to enclose silicon carbide-based integrated circuits (ICs), including circuits containing SiC-based power diodes, that are capable of operation under conditions more severe than can be withstood by silicon-based integrated...

Briefs : Electronics & Computers
A Building-Block Approach to COTS Technology

Historically, the price of non-commercial hardware has been astronomical due to the engineering required for it to perform specific functions and to operate reliably in harsh conditions, with ambient temperatures from -55° to +125°C, in high and low humidity, while withstanding extreme...

Briefs : Physical Sciences
Model of Mixing Layer With Multicomponent Evaporating Drops

A mathematical model of a three-dimensional mixing layer laden with evaporating fuel drops composed of many chemical species has been derived. The study is motivated by the fact that typical real petroleum fuels contain hundreds of chemical species. Previously, for the sake of...

Briefs : Physical Sciences
Role of Meteorology in Flights of a Solar-Powered Airplane

In the summer of 2001, the Helios prototype solar-powered uninhabited aerial vehicle (UAV) [a lightweight, remotely piloted airplane] was deployed to the Pacific Missile Range Facility (PMRF), at Kauai, Hawaii, in an attempt to fly to altitudes above 100,000 ft (30.48 km). The goal of...

Briefs : Mechanical & Fluid Systems
Blade-Pitch Control for Quieting Tilt-Rotor Aircraft

A method of reducing the noise generated by a tilt-rotor aircraft during descent involves active control of the blade pitch of the rotors. This method is related to prior such noise- reduction methods, of a type denoted generally as higher-harmonic control (HHC), in which the blade pitch is...

Briefs : Mechanical & Fluid Systems
Solar Array Panels With Dust-Removal Capability

It has been proposed to incorporate piezoelectric vibrational actuators into the structural supports of solar photovoltaic panels, for the purpose of occasionally inducing vibrations in the panels in order to loosen accumulated dust. Provided that the panels were tilted, the loosened dust would...

Briefs : Information Technology
Autonomous Environment-Monitoring Networks

Autonomous environment-monitoring networks (AEMNs) are artificial neural networks that are specialized for recognizing familiarity and, conversely, novelty. Like a biological neural network, an AEMN receives a constant stream of inputs. For purposes of computational implementation, the inputs are vector...

Briefs : Information Technology
Improved Discrete Approximation of Laplacian of Gaussian

An improved method of computing a discrete approximation of the Laplacian of a Gaussian convolution of an image has been devised. The primary advantage of the method is that without substantially degrading the accuracy of the end result, it reduces the amount of information that must be...