Test & Measurement

High-Channel-Count, High-Scan-Rate Data Acquisition System for the NASA Langley Transonic Dynamics Tunnel

The NASA Langley Research Center (LaRC) Transonic Dynamics Tunnel (TDT) has been operational since 1960, investigating a wide range of aeroelastic and non-aeroelastic phenomena. A dedicated aeroelastic test facility, the TDT is a large, variable-pressure, transonic wind tunnel. To support unique types of aeroelastic and dynamic tests, the TDT possesses a dynamic data acquisition system (DAS) with synchronous scanning of all analog channels. Steady (static) values are simply computed as the mean of any signal. The existing TDT DAS is referred to as the Open Architecture Data Acquisition System (OA-DAS). An effort was initiated to replace OA-DAS in order to increase the scan rate, increase the channel count, increase the reliability, increase user friendliness, and improve upon some features while maintaining synchronous scanning and other unique abilities. This effort has been spearheaded by researchers within the Aeroelasticity Branch (AB) co-located with the TDT; hence, the new data system has been named AB-DAS. The new data system will serve as the primary data system and will substantially increase the scan rate capabilities and analog channel count. This synchronous and dynamic system enables high-channel-count buffet and aeroacoustic tests in addition to the range of other testing done at TDT.

Posted in: Briefs, Test & Measurement, Architecture, Data acquisition and handling, Test facilities, Wind tunnel tests

Fusible Alloy Thermometer

This work was based on the need for a relatively small passive detector of maximum temperature reached by an object that can be visually inspected. The device requirements are to be hermetically sealed for contamination control, give a clear indication of maximum temperature achieved (non-reversible) with a ~10 °C resolution, have an essentially unlimited shelf-life and insensitivity to radiation, be passive without any electronics or mechanisms, provide good thermal conductivity, and be low-cost. Prior detectors have an unclear lifetime, contamination outgassing properties, and radiation tolerance. These could be used at much higher temperatures than plastic methods (>>100 °C), though out of scope for the tests performed to date.

Posted in: Briefs, Test & Measurement, Measurements, Thermodynamics, Alloys

Small-Volume Pressurized Sample Handling System

A method was developed for effective, efficient, non-destructive, in-situ sample processing. Pressure vessels are used for sample delivery and collection, a shaker is used to keep the particles suspended, a back pressure of argon gas is used to keep the system under pressure to regulate the flow, and flow restrictors and frits are used that never come into contact with the sample slurry to avoid clogs.

Posted in: Briefs, Test & Measurement, Soils, Containers, Non-destructive tests

NASA Measures Raindrop Sizes from Space

For the first time, scientists have three-dimensional snapshots of raindrops and snowflakes around the world, thanks to the joint NASA and Japan Aerospace Exploration Agency Global Precipitation Measurement (GPM) mission. With the new global data on raindrop and snowflake sizes, scientists can improve rainfall estimates from satellite data and numerical weather forecast models.

Posted in: News, Measuring Instruments, Monitoring

Advanced Capabilities of PXI-Based Semiconductor Test Systems

The ongoing challenge for today’s semiconductor test engineers is to identify and create new test solutions that can offer significantly lower test costs as well as address the need for configurable, open-architecture, flexible test solutions that can provide comparable features to proprietary ATE platforms. In particular, for test requirements with low to moderate volumes — such as pilot production, verification, and focused production test applications — the need for flexible and cost-effective ATE solutions is particularly acute. For these applications, test engineers historically have relied upon legacy test systems that have a low acquisition cost, but high operating costs or in-house designed rack-and-stack solutions. However, semiconductor test system solutions based on the PXI platform have made significant advancements in functionality and performance over the past three or four years, offering test engineers a viable alternative for both current and future test needs.

Posted in: Articles, Test & Measurement, Architecture, Semiconductors, Test equipment and instrumentation, Test procedures

Calibration Requirements for Testing Coupling-Decoupling Networks

Coupling-Decoupling Networks (CDNs) are the unglamorous workhorses that get “hitched up” to an impulse generator in order to perform impulse testing on powered equipment. As such, performance and calibration requirements for CDNs have not been specified to the same level of detail as the impulse generator. This is no longer the case with the Third Edition of IEC 61000-4-5, the international standard for surge immunity testing.

Posted in: Articles, Test & Measurement, Capacitors, Electric power, Test equipment and instrumentation

NASA Monitoring Technologies Shake Up Earthquake Prediction

The seconds to minutes of advance warning of an earthquake can allow people and systems to take actions to protect life and property from destructive shaking. Earthquake early warning systems use earthquake science and the technology of monitoring systems to alert devices and people when shaking waves generated by an earthquake are expected to arrive at their location. NASA has been one of the agencies at the forefront of earthquake early warning technology for many years, and new monitoring techniques developed by NASA are shaking up the way earthquakes are predicted.

Posted in: Articles, Test & Measurement, Weather and climate, Evacuation and escape, Satellites

Reducing Torque Measurement Uncertainty in Turbine Engine Testing

Torque is among the most important of all the measured quantities in applications ranging from characterizing high-power gas turbines, to determining the level of force required to open a screw cap on a medication container. As anyone who studied physics in high school should recall, torque is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Loosely speaking, torque is a measure of the turning force on an object such as a bolt or a flywheel. For example, pushing or pulling the handle of a wrench connected to a nut or bolt produces a torque (turning force) that loosens or tightens the nut or bolt. However, measuring torque accurately can be far from straightforward. This article offers an overview of one approach to reducing uncertainty in torque measurement using an example of turbine engine testing to illustrate the process.

Posted in: Application Briefs, Test & Measurement, Measurements, Gas turbines, Test procedures

Flow Meters

AutomationDirect (Cumming, GA) offers ProSense FMM Series magnetic-inductive flow meters (magmeters) for liquid flow monitoring in industrial processes. The magmeters, available with 1/2" to 2" NPT female process connections, are designed with a 4-digit numeric display with pushbutton setup, a 4-pin M12 quick disconnect, and two outputs. The stainless steel design mounts directly in-line.

Posted in: Products, Manufacturing & Prototyping, Test & Measurement

Pulsed Test Instrument

Instruments for Industry, a unit of AMETEK Compliance Test Solutions (Edison, NJ) introduced the S21-4KWP-2KWP FLEX solid-state micro wave pulse power amplifier with a frequency range of 1.0 GHz to 2.0 GHz. It supplies 4 kW of pulse power up to 10% duty cycle with a maximum pulse width of 100 uS. The amplifier can be configured into two separate 2-kW pulse amplifiers for lower-power requirements at multiple locations. Safety features include RF and hardware protection circuits such as voltage standing wave ratio (VSWR), over current, voltage protection, and redundant thermal and airflow sensors for the module and full system. The user interface features a backlit screen that shows forward/reverse power indication, system status, and self-diagnostic information.

For Free Info Visit http://info.hotims.com/61060-401

Posted in: Products, Manufacturing & Prototyping, Test & Measurement

The U.S. Government does not endorse any commercial product, process, or activity identified on this web site.