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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Microminiaturization of optimized laboratory speech-compression system for spacecraft application - microcircuit technology and determination of most feasible design approach
Environmental testing of microminiature high level multicoder for spacecraft
Microminiaturized telemetry system to monitor biological functions
Basic circuitry for microminiature dc integrated- circuit, direct-coupled, signal-conditioning amplifier
Design, fabrication, testing, and operation of microminiature rate of turn vibratory sensor
Literature survey and instrumentation evaluation to determine feasibility of developing microminiaturized devices for bioastronautics monitoring and analysis
Microminiature thermocouple makes precision gas sidewall temperature readings inside large thrust chambers. It is installed by a technique whereby the sensor monitors its own installation to insure against thermal damage to the thermocouple and ensure minimum disturbance to chamber surfaces.
Microminiaturized solid state devices for bioastronautical monitoring or analysis
Reliability analysis and failure rates for microminiature high level multicoder
Analog digital filters, converters, and microminiaturized circuits for bioastronautical application
Operation and testing of spacecraft microminiature PAM decommutator system
Microminiaturized devices for bioastronautical monitoring or analysis
Microminiature solid state LSI imaging system design, construction and performance characteristics
Techniques commonly used for fabrication of integrated circuits are utilized to produce long capillary tubes for microminiature chromatographs. Method involves bonding of flat silicon plate to top of spirally grooved silicon chip to close groove and form capillary column.
The microminiaturization of an electronic analog signal to discrete time interval converter is presented. Discrete components and integrated circuits comprising the converter were assembled on a thin-film ceramic substrate containing nichrome resistors with gold interconnections. The finished assembly is enclosed in a flat package measuring 3.30 by 4.57 centimeters. The module can be used whenever conversion of analog to digital signals is required, in particular for the purpose of regulation by means of pulse modulation. In conjunction with a precision voltage reference, the module was applied to control the duty cycle of a switching regulator within a temperature range of -55 C to +125 C, and an input voltage range of 10V to 35V. The output-voltage variation was less than + or - 300 parts per million, i.e., less than + or - 3mV for a 10V output.
Ions, such as proton (pH) and potassium, play a crucial role in body fluids to maintain proper basic functioning of cells and tissues. Metabolites, such as glucose, control the energy available to the entire human body in normal as well as stress situations, and before, during, and after meals. These molecules diffuse easily between blood in the capillaries and the interstitial fluid residing between cells and tissues. We have developed and approach to monitoring of critical ions (called electrolytes) and glucose in the interstitial fluid under the human skin. Proton and potassium levels sensed using optode technology that translates the respective ionic concentrations into variable colors of corresponding ionophore/dye/polymeric liquid membranes. Glucose is monitored indirectly, by coupling through immobilized glucose oxidase with local pH that is then detected using a similar color scheme. The monitor consists of a tiny plastic bar, 100-200 microns wide and 1-2 mm long, placed just under the skin, with color changing spots for each analyte as well as blanks. The colors are read and translated into concentration values by a CCD camera. Direct optical coupling between the in vivo sensing bar and the ex vivo detector device requires no power, and thus eliminates the need for wires or optical fibers crossing the skin. The microminiature bar penetrates the skin easily and painlessly, so that astronauts could insert it themselves. The approach is fully compatible with telemetry in space, and thus, in vivo clinical data will be available real time in the Earth based command center once the device is fully developed. The information provided can be used for collecting hitherto unavailable vital data on clinical effects of space travel. Managing clinical emergencies in space with the sensor already in place should also become much more efficient than without a continuous monitor, as is currently the case. Civilian applications may include better glucose control of patients with moderate to severe diabetes: a growing health problem in the US and World-wide.
16-channel FM telemetry system with voltage controlled oscillator
RC distributed analysis, dc to dc converters, digital filters, and oximeter