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Choate, R.

Publications and source records attributed to Choate, R..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1974

Martian and lunar science with remotely-controlled long-range surface vehicles

Science objectives are outlined for long surface traverse missions on Mars and the moon, with remotely-controlled roving vehicles. Series of candidate rover science payloads are proposed, varying in purpose, development needed, cost, and weight (35 to almost 300 kg). A high degree of internal control will be needed on the Mars rover, including the ability to carry out complex science sequences. Decision-making by humans in the Mars mission includes supervisory control of rover operations and selection of features and samples of geological and biological interest. For the lunar mission, less control on the rover and more on earth is appropriate. Operational problem areas for Mars include control, communications, data storage, night operations, and the mission operations system. For the moon, science data storage on the rover would be unnecessary and control much simpler.

Jaffe, L. D.↗
NASA NTRS1973

Unmanned surface traverses of Mars and Moon: Science objectives, payloads, operations

Science objectives and properties to be measured are outlined for long surface traverse missions on Mars and the Moon, with remotely-controlled roving vehicles. A series of candidate rover payloads is proposed for each planet, varying in weight, cost, purpose, and development needed. The smallest weighs 35 kg; the largest almost 300 kg. A high degree of internal control will be needed on the Mars rover, including the ability to carry out complex science sequences. Decision-making by humans in the Mars mission includes supervisory control of rover operations and selection of features and samples of geological and biological interest. For the lunar mission, less control on the rover and more on earth is appropriate. Science portions of the rover mission profile are outlined, with timelines and mileage breakdowns. Operational problem areas for Mars include control, communications, data storage, night operations, and the mission operations system. For the moon, science data storage on the rover would be unnecessary and control much simpler.

Jaffe, L. D.↗
NASA NTRS1973

Science aspects of a remotely controlled Mars surface roving vehicle.

Particular attention is given to aspects pertinent to teleoperation, remote control, onboard control, and man-machine relationships in carrying out scientific operations with such a vehicle. It is assumed that landed operations would comprise one Martian year and that the traverse would extend across an area approximately 500 km wide. The mission is assumed to be planned for the early 1980s. Its objective is to obtain data which will aid in answering a number of questions regarding the history of the solar system, the formation of Mars, and the evolution of life on Mars. A series of candidate rover payloads is proposed to meet the requirements. The smallest payload includes a TV camera, a general-purpose manipulator arm, a crusher and siever, an X-ray diffractometer-spectrometer, a gravimeter, a magnetometer, meteorological instruments, and a radio transponder.

Choate, R.↗
NASA NTRS1972

Spacecraft techniques for lunar research.

The most significant findings about the Moon obtained by spacecraft so far, have resulted from measurements of gravity, electromagnetic properties, seismicity, mechanical properties, geologic features, composition, ages, and the lunar environment. A number of major lunar questions remain to be answered. Other properties, measurable with spacecraft, which may provide data critical to answering these questions include geometrical shape, motions, and heat flow. In this paper specific measurements that should provide critical data for each of these questions are identified, with some candidate techniques. Among the suggested techniques that have not yet been used are very long baseline interferometry (Earth-Moon baseline), gravity gradiometry, elemental analysis by neutron interactions, and remotely-controlled on-moon microscopy.

Jaffe, L. D.↗
NASA NTRS1969

Lunar soil coefficient of friction determined from Surveyor data and laboratory tests

A series of laboratory tests on simulated soils was conducted to evaluate some of these physical properties. Using soils similar to lunar soil composition, particle size distribution, and cohesion as determined from the Surveyor mission, the coefficient of friction and bulk density were evaluated by reproducing soils with the same force vs penetration characteristics as demonstrated at the Surveyor landing sites. The determination of soil coefficient of friction is presented in this paper; the soil density is treated separately in the previous paper’ of this report.

Choate, R.↗
NASA NTRS1967

Lunar surface mechanical properties

Lunar surface mechanical properties determined by landing impacts, telemetry data from Surveyor III, and comparison of data collected by Surveyor I and Surveyor III

LUNAR SURFACE↗