Test & Measurement

Electromechanical Testing of Microelectromechanical Devices

Devices would be probed at the wafer level before dicing and packaging. A method of electromechanical testing has been proposed for general diagnosis, evaluation of performance, and burn-in (accelerated life testing) of microelectromechanical devices. The tests would ordinarily be performed at the wafer level; that is, after the devices have been fabricated on wafers but before the wafers have been diced and the dies packaged. Alternatively or in addition, the tests could be performed at other stages of the fabrication process.

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Automated Apparatus for Testing Gyroscopes

Except for initial setting of conditions, the entire testing process is automated. The Gyroscope Automated Testbed is a computer-controlled apparatus designed primarily for automated testing of vibratory gyroscopes. It can also be used to test other devices: By changing testing-system/tested-device interface circuitry that is part of the apparatus, one can set up the apparatus to test nonvibratory gyroscopes. The apparatus can also be used as a general-purpose noise-analysis system for characterizing a variety of devices in addition to gyroscopes.

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Measuring NO and OH Concentrations at High Pressure

An optoelectronic laboratory apparatus could be developed into a portable instrument. An apparatus based on line-of-sight resonant absorption of ultraviolet light yields measurement data from which one can calculate the concentrations of nitric oxide (NO) and of hydroxyl radicals (OH) in a laboratory flat flame at a pressure up to 30 atm ≈3 MPa). The basic measurement principle is distinct from the principles of laser-induced fluorescence and other laser diagnostic techniques; hence, the data generated by this apparatus could provide independent verification of data from laser-based instruments.

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Laser Heating for Testing Rocket-Engine Insulating Phenolic

A continuous-wave CO2 laser has been selected as a source of heat for testing the thermal response of carbon-cloth phenolic like that used as insulating material in a reusable solid-fuel rocket motor (RSRM). The particular thermal response of interest, observed during operation of an RSRM, is pocketing. By suitable adjustment of the size and power of the laser beam, the rate of heating can be made nearly identical to that in the RSRM nozzle during operation.

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Software for Testing Access List Integrity

Many networks rely on firewalls or filtering routers for frontline network security. Packet filtering firewalls or routers filter incoming or outgoing packets based on a set of access rules. The IP (Internet Protocol) Packet Generator computer program assists in verifying that a packet filtering firewall is configured correctly, by detecting security holes in the firewall's filtering rules.The IP Packet Generator enables the user to build TCP/IP (Transmission Control Protocol/Internet Protocol) packets and transmit them via the network, to detect errors in access list configuration.The user can specify the source IP address of a packet to simulate attempted access from a remote host. The user can also specify the destination IP address, the type of packet, the destination port number, the size of the packet, the number of packets to send, and the packet rate. Thus, the software helps the user perform an exhaustive test of the access list.

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Improved Electrical-Impedance Body-Fluids Monitor

Measurements that yield a variety of data can be done quickly, frequently, and safely. The Johnson Space Center (JSC) body-fluids monitor advances the state of the art of measuring hydration levels in humans during spaceflight. Neither bulky nor heavy, this noninvasive instrument is built around a commercial inductance-capacitance-resistance meter, which is used to obtain electrical-impedance-vs.-frequency data for equivalent-circuit/electrical-components analyses. The instrument is expected to prove invaluable not only in space-flight settings but also in such other settings as veterans' hospitals, clinical facilities, and medical research laboratories.

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Apparatus Measures Thermal Conductance Through a Thin Sample From Cryogenic to Room Temperature

An apparatus allows the measurement of the thermal conductance across a thin sample clamped between metal plates, including thermal boundary resistances. It allows in-situ variation of the clamping force from zero to 30 lb (133.4 N), and variation of the sample temperature between 40 and 300 K. It has a special design feature that minimizes the effect of thermal radiation on this measurement.

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