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Laeser, R. P.

Publications and source records attributed to Laeser, R. P..

7 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1986

Engineering the Voyager Uranus mission

Several factors that affected the continuing expedition of Voyager 2 to Uranus are discussed. The hydrazine propellant and electrical power supplies on the spacecraft, and the radio signal strength and sun sensor and star tracker sensitivities are examined. The use of the on-board computer to steady the spacecraft and reduce image smear is described. The Voyager employs radiometric and optical data to navigate. The changes required to improve the transmission capabilities of the spacecraft and to eliminate the on-board hardware failures are analyzed.

Laeser, R. P.↗
NASA NTRS1985

Voyager-Uranus at our doorstep

Following the encounter of Voyager 2 with Saturn and the subsequent approach, in January 1986, to the planet Uranus, the NASA Deep Space Network (DSN) undertook a reshaping of Voyager's end-to-end data system to provide communication to earth with a sufficient number of images for Uranus characterization. In-flight evolution of the spacecraft and ground system is described, with particular attention given to the aspects of target motion compensation, line enhancement, arraying, and encoding data streams. Solutions to the on-board problems encountered during the flight are presented. Voyager and its principal elements, an actuator for the scan platform, and the coding diagram are among the illustrations included.

Laeser, R. P.↗
NASA NTRS1981

Operational compensation for effect of close Titan flyby on remainder of Voyager 1 Saturn near encounter

The satellite instrument pointing update process (SPUP) developed for the Voyager 1 Saturn encounter is assessed. At certain times, navigation errors translated into target pointing errors, impede camera operation. Two sigma pointing accuracy of 1.5 to 2.0 mrads per axis was required. The SPUP combines correction slews implemented by immediate action commands with preevent modifications. The process worked perfectly, producing good quality images of target areas.

Laeser, R. P.↗
NASA NTRS1972

Tracking and data system support for the Mariner Mars 1971 mission. Prelaunch phase through first trajectory correction maneuver, volume 1

The DSN command system provided the capability to enter commands in a computer at the deep space stations for transmission to the spacecraft. The high-rate telemetry system operated at 16,200 bits/sec. This system will permit return to DSS 14 of full-resolution television pictures from the spacecraft tape recorder, plus the other science experiment data, during the two playback periods of each Goldstone pass planned for each corresponding orbit. Other features included 4800 bits/sec modem high-speed data lines from all deep space stations to Space Flight Operations Facility (SFOF) and the Goddard Space Flight Center, as well as 50,000 bits/sec wideband data lines from DSS 14 to the SFOF, thus providing the capability for data flow of two 16,200 bits/sec high-rate telemetry data streams in real time. The TDS performed prelaunch training and testing and provided support for the Mariner Mars 1971/Mission Operations System training and testing. The facilities of the ETR, DSS 71, and stations of the MSFN provided flight support coverage at launch and during the near-earth phase. The DSSs 12, 14, 41, and 51 of the DSN provided the deep space phase support from 30 May 1971 through 4 June 1971.

Laeser, R. P.↗
NASA NTRS1970

The first Mars orbiters

Mariner-type spacecraft launch in 1971 to orbit Mars, discussing onboard experiments and instrument

Forney, R. G.↗