Dual-Cavity Rayleigh Scattering Measurement System

A method and apparatus were developed for simultaneous measurement of velocity, density, temperature, and their spatial and temporal derivatives in gas flow. Langley Research Center, Hampton, Virginia Molecular-based optical diagnostics techniques capable of obtaining simultaneous measurements of multiple fluid properties are critically important for characterizing hypersonic air-breathing engines, such as scramjet engines and scramjet-rocket combined cycle engines. Correlations between those properties lead to a more detailed understanding of complex flow behavior, and aid in the development of multiparameter turbulence models required for supersonic combustion engine flow path predictions.

Posted in: Briefs, TSP, Instrumentation, Optics, Measuring Instruments, Test & Measurement


Miniature Laser Magnetometer

This conceptual design includes three key innovations future space science requires while minimizing size, mass, and power. Goddard Space Flight Center, Greenbelt, Maryland Space missions using magnetometers have been very successful. However, science missions now require higher levels of accuracy and stability in order to refine existing understanding and improve modeling. In most space missions that require high-accuracy vector measurement of magnetic fields, a separate scalar magnetometer must also be included in order to calibrate the vector measurements. The miniature laser magnetometer (MLM) addresses the need for a single, high-stability magnetometer instrument that provides both scalar and vector measurements for future space science needs while minimizing size, mass, and power.

Posted in: Briefs, TSP, Aerospace, Instrumentation, Lasers & Laser Systems, Measuring Instruments, Test & Measurement


Cryogenic Slosh Apparatus

John F. Kennedy Space Center, Florida Commercially available components are integrated into an assembly that can be used to measure the slosh dynamics of cryogenic liquids. The apparatus consists of a linear motion table that is properly instrumented to record highfidelity position, force, and acceleration measurements of all linear and rotation responses of the cryogenic liquid.

Posted in: Briefs, Instrumentation, Measuring Instruments, Test & Measurement


Negative-Ion Time Projection Chamber Polarimeter for Measuring Polarization of Bright Transient Astrophysical Sources

Goddard Space Flight Center, Greenbelt, Maryland A negative ion time projection chamber (NI-TPC) was developed that is suitable for measuring the polarization of bright transient events. The polarization of the astrophysical source is determined by imaging photoelectron tracks created by incident x-rays interacting in a gas. The tracks drift through the gas under a uniform electric field to the readout electronics. The initial photoelectron direction is correlated with the polarization of the incident x-ray, and therefore by imaging many tracks, one can determine the polarization magnitude and direction of the incident x-rays.

Posted in: Briefs, TSP, Instrumentation, Measuring Instruments, Test & Measurement


Nonlinear Swept Frequency Technique for CO2 Measurements Using a CW Laser System

The measurements would be used to significantly reduce the uncertainties in global estimates of CO2, improve climate models, and close the carbon budget for improved forecasting and policy decisions. The U.S. National Research Council recently identified the need for a near-term space mission of Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS). The primary objective of the ASCENDS mission is to make CO2 column measurements across the troposphere during the day and night over all latitudes and all seasons, and in the presence of scattered clouds. These measurements would be used to significantly reduce the uncertainties in global estimates of CO2 sources and sinks, provide an increased understanding of the connection between climate and CO2 exchange, improve climate models, and close the carbon budget for improved forecasting and policy decisions.

Posted in: Briefs, TSP, Green Design & Manufacturing, Greenhouse Gases, Lasers & Laser Systems, Test & Measurement


Advanced Rolling Mechanics Analysis (AROMA) 1.0

Lyndon B. Johnson Space Center, Houston, Texas AROMA uses a boundary-element formulation to calculate normal and shear pressure distributions and sub-surface stresses for elastic bodies in contact. In addition to handling static normal and sheer loading, it also solves the contact problem for rolling elements such as bearings, traction drives, and wheel-to-rail interfaces. AROMA is a powerful and flexible tool for studying the tractive forces that arise during rolling in combination with kinematic effects, such as creepage and spin that are related to rolling element alignment. This GUI-based tool was developed in MATLAB, and can run within the MATLAB environment or as a standalone application.

Posted in: Briefs, Motion Control, Software, Measuring Instruments


Product of the Month: March 2015

Instron, Norwood, MA, introduced the AVE 2 strain measurement system that conforms to testing standards such as ISO 527, ASTM D3039, and ASTM D638. The video extensometer utilizes patented measurement technology, and adapts to the normal fluctuations of indoor environmental conditions. It can be adapted to any testing machine that uses a ±10V analog input. Designed to reduce errors from thermal and lighting variations, the device uses the real-time 490-Hz data rate while achieving a 1-micron accuracy. It allows for testing under multiple environmental conditions and can be used for strain measurement with Digital Image Correlation (DIC). The device measures both modulus and strain-to-failure of most materials including plastics, metals, composites, textiles, films, and bio-materials.

Posted in: Products, Manufacturing & Prototyping, Materials, Measuring Instruments


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