Search NASASearch

Engineering topics

Couch, R. H.

Publications and source records attributed to Couch, R. H..

The Lidar In-Space Technology Experiment (LITE)

The characteristics of a large lidar system, the Lidar In-Space Technology Experiment (LITE), which is being developed for launch in 1994 into an earth orbit, are described together with the type of investigations to be performed by LITE. LITE will measure atmospheric parameters such as cloud heights, profiles of aerosols and temperature, and surface characteristics. The experiment is modular in design and can be used as a testbed for the evolution of future lidar designs and technologies. Diagrams of the LITE hardware pallet configuration for Shuttle flights, the LITE telescope receiver configuration, and the optics bench layout are presented.

Mccormick, M. P.

A lidar technology experiment from Space Shuttle - Lidar In-Space Technology Experiment (LITE)

Plans to conduct a technology experiment with a Shuttle-based lidar instrument are described. The design of the Lidar In-Space Technology Experiment (LITE) is presented, including performance goals for the laser transmitter, telescope, optical receiver, and associated electronics. Experimental results from space flight of the LITE instrument are used to define performance criteria and designs for future atmospheric sounding experiments planned for the Space Station, Earth Observing System platform, and for more complex scientific lidar experiments.

Poole, H. E.

Hot melt adhesive attachment pad

A hot melt adhesive attachment pad for releasably securing distinct elements together is described which is particularly useful in the construction industry or a spatial vacuum environment. The attachment pad consists primarily of a cloth selectively impregnated with a charge of hot melt adhesive, a thermo-foil heater, and a thermo-cooler. These components are securely mounted in a mounting assembly. In operation, the operator activates the heating cycle transforming the hot melt adhesive to a substantially liquid state, positions the pad against the attachment surface, and activates the cooling cycle solidifying the adhesive and forming a strong, releasable bond.

Fox, R. L.

Miniature Temperature-Control Circuit

Operates on any power supply voltage from 6 to 28 volts. Miniature thermostate circuit controls electric heating element to maintain constant temperature in oven or other thermal environment.

Couch, R. H.

An investigation of the existence of a surface water layer on aircraft radomes during simulated flight in heavy precipitation

An experiment to investigate the electromagnetic attenuation effects of an impacting water spray on an aircraft weather radome was conducted in Langley's 4 X 7 m. wind tunnel equipped with a water spray system. Results indicate no significant liquid water film formed at the stagnation point of the radome under the test conditions. However, a water sheath was observed standing away from the radome surface, which could possibly have significant attenuation properties of its own. Due to the lack of fidelity in modeling both the natural environment with the tunnel apparatus and the water sheath, it is recommended that further studies be undertaken to better define the water distribution in the vicinity of the radome and measure its effect on weather radar performance.

Branstetter, J. R.

STEP electronic system design

The STEP electronic system design is discussed. The purpose of the design is outlined. The electronic system design is summarized and it is found that: an effective conceptual system design is developed; the design represents a unique set of capabilities; makes efficient use of available orbiter resources; the system capabilities exceed identified potential experiment needs.

Couch, R. H.

Hot-Melt Adhesive Attachment System

Adhesive system is as effective on Earth as in space. Fiberglass cloth mounted in head assembly. When adhesive reaches melt temperature head is attached to metals composites, ceramics, and other materials. Once attached, head cooled rapidly for quick stick. Used to tether tools or attach temporary scaffolding to walls, buildings, or beams.

Fox, R. L.

Microprogramed Sequencer for Tunable RF Oscillator

Standard IC chips and digitally tuned oscillator combined. Circuit consists of PROM-based microprogramed control sequencer, which drives group of diode switches to select one of eight tuning capacitors in L-C oscillator. Circuit originally designed to "dither" transmitter frequency of K-band radar at high rates finds application in other areas, as automated test equipment or computer-controlled receiver tuning.

Couch, R. H.

Temperature controller for hyperthermia devices

Temperature controller monitors and controls temperature in local region of tumor. Medical grade thermocouples are inserted in or near tumor, controller pulse modulates radio frequency diathermy power source to maintain temperature within 0.2 C. System may be extended to control diathermy of more than one tumor or patient.

Couch, R. H.

Microwave radar and radiometric remote sensing measurements of lake ice

Simultaneous microwave radar and spectral radiometric data were collected over Lake Erie during March 1978. A theoretical development is presented which interprets the data collected at nadir in terms of changes in the ice thickness and the electromagnetic attenuation coefficient. The theory also addresses the failure of the spectral radiometer to determine ice thickness through observations of quarter wavelength excursions in the reflectivity. Radar data collected off-nadir showed a substantially different behavior compared to that collected near nadir. This difference is attributed to a change in propagation characteristics from quasi-specular return from the ice-water interface to scattering from the rough air-ice interface.

Swift, C. T.

Teletype test unit

Device may be used to facilitate testing and fault isolation in teletype and modem systems that are used for communication by people who having hearing disabilities. Unit uses CMOS digital integrated circuitry which may be operated from relatively inexpensive battery of any voltage from 3 to 18 volts.

Couch, R. H.

An airborne remote sensing 4.5 to 7.2 gigahertz stepped frequency microwave radiometer

A microwave stepped frequency radiometer operating from 4.5 to 7.2 gigahertz has been designed, fabricated and flight tested in an airborne remote sensing mission by NASA Langley Research Center. This paper describes the design of this precision microwave Dicke-switched noise feedback radiometer, calibration techniques and presents typical results from remote sensing mission employing this radiometer.

Harrington, R. F.

Phase modulating with odd and even finite power series of a modulating signal

Method and apparatus is presented for producing a phase-modulated waveform having a high degree of linearity between the modulating signal and the phase of the modulated carrier signal. Two signals representing finite odd and even power series transformations of the modulating signal are produced and multiplied with two quadrature components of the input carrier signal, respectively. One of the multiplied signals is subtracted from the other and the resulting signal is hard-limited to produce a phase-modulated output signal. The means for producing the two signals representing the odd and even power series of the modulating signal includes means for varying the coefficients of the two power series. By means of an existing computer program, the coefficients of the two power series are selected such that there is an extremely high degree of linearity between the modulating signal and the phase of the modulated carrier signal.

Hearn, C. P.

Wide deviation phase modulator

Modulator produces phase-modulated waveform having high modulating linearity. Technique is inherently wideband with respect to carrier frequency and can operate over decade carrier frequency range without adjustments. Circuit performance is both mathematically predictable and highly reproducible.

Couch, R. H.

Apparatus for aiding a pilot in avoiding a midair collision between aircraft

An apparatus for aiding a pilot in avoiding a midair collision between aircraft is described. A protected aircraft carries a transmitter, a transponder, a receiver, and a data processor; and an intruding cooperating aircraft carries a transponder. The transmitter of the protected aircraft continuously transmits a signal to the transponders of all intruding aircraft. The transponder of each of the intruding aircraft adds the altitude of the intruding aircraft to the signal and transmits it back to the receiver of the protected aircraft. The receiver selects only the signal from the most hazardous intruding aircraft and applies it to the data processor. From this selected signal the data processor determines the closing velocity between the protected and intruding aircraft, the range between the two aircraft, their altitude difference and the time to a possible collision.

Schrader, J. H.