Keyword: Calibration

Briefs: Physical Sciences

"Health check" would be built into pressure transducers, according to a proposal, to enable occasional, rapid, in situ testing of the transducers between normal pressure-measurement...

Briefs: Test & Measurement
A Mass-Spectrometer System for Detecting Gas Leaks

The Hydrogen Umbilical Mass Spectrometer (HUMS) consists of an integrated sample delivery system, a commercial mass-spectrometer- based gas analyzer, and a set of calibration gas mixtures traceable to NIST (National Institute for Standards and Technology). The system, except for the calibration...

Briefs: Photonics/Optics

A spatially modulated prism interferometer (SMPI) has been developed that overcomes the complexities of traditional interferometers and the inherent limitations of diffraction gratings, dispersion...

Briefs: Test & Measurement
A Mass-Spectrometer System for Detecting Gas Leaks

The Hydrogen Umbilical Mass Spectrometer (HUMS) consists of an integrated sample delivery system, a commercial mass-spectrometer-based gas analyzer, and a set of calibration gas mixtures traceable to NIST (National Institute for Standards and Technology). The system, except for the calibration...

Briefs: Software
Software for Processing RADARSAT ScanSAR Data Into Images

SAR Processing System ScanSAR Processor (SPS SSP) is a computer program that is used in the Alaska SAR Facility (ASF) to processes scanSAR downlink data from the RADARSAT (a Canadian Earth-observation satellite) into a suite of image data products. ["SAR" means "synthetic-aperture...

Briefs: Software
Software for Obtaining Ideal SAR Chirps

A computer program introduces a predistortion into the chirp signal used to frequency-modulate a synthetic-aperture-radar (SAR) signal at the transmitter. The predistortion is intended to compensate for distortions introduced by nonideal performance of the various pieces of SAR equipment — especially the...

Briefs: Electronics & Computers

Two airborne spectrum analyzers were developed for acquiring dynamic data, characterized by frequencies up to 25 kHz, from a hypersonic-crossflow-transition experiment aboard the...

Briefs: Test & Measurement

An algorithm has been devised to greatly simplify and improve the calibration and the reduction of systematic noise of an imaging interferometer or other similar interferometric instrument....

Briefs: Test & Measurement

A miniature birefringence-measuring system has been developed for use in investigating extensional flows of non-Newtonian polymers in microgravity. The system could also be used on Earth to perform...

Briefs: Information Technology
Software for Ground Processing of Data From Landsat 7

Three computer programs have been developed for ground processing of Enhanced Thematic Mapper Plus (ETM+) data from Landsat 7. The three programs and their functions are the following:

Briefs: Motion Control

A proposed method of calibration of micromachined vibratory gyroscopes would make it unnecessary to test the gyroscopes at known rates of rotation. At present, calibration entails inertial...

Briefs: Information Technology
A Standard for Scientific Data Files

The term "Instrument Data File Set" (IDFS) denotes both software and an underlying concept of a prescribed format for files of scientific data and metadata. The IDFS was developed to satisfy a need, in the space science community, to maintain data and metadata in a format that promotes efficient use of the...

Briefs: Mechanical & Fluid Systems

Work performed at Johnson Space Center has brought about a major improvement in the means for measuring the bending that occurs whenever stress is applied to a bolted joint. This major improvement...

Briefs: Physical Sciences

A temperature correction has been developed to enable the extraction of pressure images and corresponding pressure data from images of photoluminescence of pressure-sensitive paints (PSPs)....

Briefs: Photonics/Optics

A complementary metal oxide/semiconductor (CMOS) focal-plane readout circuit for an imaging array of long-wavelength infrared (LWIR) photodetectors effects in-pixel current-mode...

Briefs: Mechanical & Fluid Systems

Mathematical models to approximate the dynamics of aircraft are often generated by considering aircraft structures to be rigid bodies. These models may be unsuitable for evaluating...

Briefs: Robotics, Automation & Control

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: Photonics/Optics
High-Speed Image Detectors With Subelectron Noise Floors

Parallel ultra-low-noise hybrid detectors (PHUDs) are developmental image-detector devices for use in low-power, scientific-grade video cameras. The hybrid nature of a PHUD lies in the incorporation of both charge-coupled-device (CCD) image-detection circuitry and complementary metal...

Briefs: Electronics & Computers

The Shuttle Projects Information Frontier (SPIF) Telemetry and Command Processor (TAC) is a personal-computer-based data-handling system that serves as part of an interface for...

Briefs: Mechanical & Fluid Systems

Direct measurement of aircraft-engine thrust by use of strain gauges offers several advantages over traditional model-based methods of calculating thrust, provided that care is...

Briefs: Manufacturing & Prototyping

Electron-beam (e-beam) lithography has shown promise as a technique for fabricating diffractive optical elements on nonflat substrates. Such optical elements could include convex or...

Briefs: Physical Sciences
Low-Distortion Imaging Spectrometers

"Pushbroom" imaging spectrometers of a proposed type would exhibit little or no distortion in either the spectral or spatial direction. These spectrometers would feature modified Offner optics, which afford a desirable combination of compactness and a high degree of optical correction. Although Offner optics...

Briefs: Electronics & Computers

Modules of electronic circuitry that perform the amplitude- and phase-control and the status-monitoring functions for eight-element (2 ×4) subarrays of K-band phased-array antennas...

Briefs: Physical Sciences
Microlenses for Calibrating Phase Doppler Particle Analyzers

Simple optical devices called "scattering reticles" have been invented for calibrating Phase Doppler Particle Analyzers (PDPAs), which are optical instruments that analyze scattered light to determine the sizes and velocities of droplets. A scattering reticle comprises a polymeric...

Briefs: Electronics & Computers

A single-block fixture enables the rapid and accurate electrical characterization of planar microwave electronic components, by use of the through-reflect-line (TRL) technique, in...

Briefs: Physical Sciences

Easy-to-use high-temperature strain-sensor systems based on strain gauges made from Pd/Cr-alloy wires have been developed. These systems include strain-gauge units comprising Pd/Cr wires...

Briefs: Physical Sciences
Automated Calibration of Temperature Transducers

An automated system of laboratory equipment and computer hardware and software reduces the time that technicians must spend in calibrating temperature transducers. The laboratory equipment includes a controlled-temperature bath, two digital multimeters for processing the outputs of two...

Briefs: Mechanical & Fluid Systems
Automated Calibration of Torque Analyzers Without Weights

An automated apparatus calibrates digital torque analyzers that, in turn, are used to verify the accuracies of torque wrenches. The apparatus is located in a central laboratory, and the digital torque analyzers are brought to the laboratory for calibration. Previously, the torque...

Briefs: Physical Sciences

The figure schematically illustrates an improved apparatus for generating a flow of gas with precise, stable humidity. Such flows are needed for calibration of dew-point, frost-point, and...