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Rupp, Charles C.

Publications and source records attributed to Rupp, Charles C..

Jovian electrodynamic tether experiment

A case is made for an electrodynamic tether scientific platform to be put into orbit around Jupiter as a follow-on to the present series of earth-based Tethered Satellite System (TSS) experiments. Preliminary system trades are made to bound the amount of power (assuming 100 percent plasma contactor efficiency) that can be obtained from the orbiting Jovian tether. With magnetic field strengths of roughly 4 to 7 Gauss, power levels of the order of 100 kilowatts can be obtained with a thin 500 km long tether. This should suffice to power a Jovian scientific experiment package. The electrodynamic tether also affords a loitering capability as it can be operated as a thruster in addition to a power generator. Further study and research is needed to characterize the Jovian tether as to its electrodynamic and dynamic performance potential. Hollow cathode plasma contactor operation needs to be verified in near earth space.

Hammond, Walter E.

Small Expendable-tether Deployer System (SEDS) development status

Plans for proposed flight of the Small Expendable-tether Deployer System (SEDS) on a Delta II launch vehicle are discussed. The SEDS tether concept and mission requirements are outlined. Results are presented from calculations of the tether dynamics and computer modeling to determine tether behavior. The tether's thermal characteristics, electronics system, material, data collection procedure, payload, and orbital trace are described.

Harrison, James K.

Coding Ropes For Length And Speed Measurements

Ferromagnetic staples serve as markers. Like crude magnetic-tape-playback head, sensor detects ferromagnetic staples as rope is unwound or wound. Pulses from staples analyzed electronically; numbers of pulses and intervals between them interpreted in terms of velocity of rope and length payed out. Adaptable to laying submarine cables and contstruction of suspension bridges.

Rupp, Charles C.

Tether Dynamics Simulation Workshop summary

The Tether Dynamics Simulation Workshop focused on the efforts of the Tether Applications Simulation Working Group (TASWG) to catalog various dynamics simulations, document environmental models, and provide a set of verified simulation results. The workshop consisted of reports on these activities and the presentation of papers on current dynamics topics of general interest. This paper documents the work performed at the Workshop and the results and recommendations for further work.

Rupp, Charles C.

Early tether dynamics flight experiments

This paper proposes an evolutionary series of tether-dynamics flight experiments using the Small Expendable Deployer System (SEDS). Such experiments could be launched as secondary payloads on the Delta ELV. The purpose of the series of experiments is to acquire data on tether deployment rate, tension, tether shape, and operating environment to compared with computer-based tether simulations. A second purpose is to serve as a precursor for the Orbiter-based SEDS, since both the tether deployer and the flight profile are similar. Additional flights could observe tether dynamics over a much wider range of operational and environmental conditions and could employ more comprehensive measurements.

Rupp, Charles C.

Get-Away tether experiment - Experimental plans

The experimental capabilities of the Get-Away Tether Experiment (GATE) are presented and a series of demonstration mission are proposed. The GATE is a free-flying tether system that will develop or demonstrate technology in the areas of tether dynamics (deployment and stabilization, retrieval, stationkeeping, and severance), tether electrodynamics, micrometeor hazards to tethers, and disturbance rejection. The system consists of two subsatellites connected by 1 km of tether. The free-flying system is ejected from the Orbiter via a Getaway Special (GAS) canister. Two dynamics missions are profiled along with a description of electrodynamic mission capabilities. The dynamic interactions of the end body and tether may be observed from the Orbiter or from an on-board video tracking system. Hence, GATE provides a unique, low cost capability to demonstrate various tether technologies, and address critical design and safety issues associated with future tether applications. An assessment of the significant measurable parameters and associated instrumentation is given. Future work and system development projection schedules are also outlined.

Greene, Michael

A manned Mars artificial gravity vehicle

Data are presented on an artificial-gravity vehicle that is being designed for a manned Mars mission, using a 'split-mission' concept, in which an unmanned cargo vehicle is sent earlier and stored in a Mars orbit for a rendezvous with a manned vehicle about 1.5 years later. Special attention is given to the vehicle trajectory and configuration, the tether design, and the vehicle weight and launch requirements. It is shown that an artificial-G vehicle for a manned Mars missions is feasible technically and programmatically. Using an artificial-G vehicle instead of a zero-G vehicle for the piloted portion of a split mission provides physiological and human-factor-related benefits, does not eliminate requirements for zero-G countermeasures research (since zero-G is an abort mode), and could possibly reduce some life science activities. Diagrams are included.

Schultz, David N.

Space Station tethered waste disposal

The Shuttle Transportation System (STS) launches more payload to the Space Station than can be returned creating an accumulation of waste. Several methods of deorbiting the waste are compared including an OMV, solid rocket motors, and a tether system. The use of tethers is shown to offer the unique potential of having a net savings in STS launch requirement. Tether technology is being developed which can satisfy the deorbit requirements but additional effort is required in waste processing, packaging, and container design. The first step in developing this capability is already underway in the Small Expendable Deployer System program. A developmental flight test of a tether initiated recovery system is seen as the second step in the evolution of this capability.

Rupp, Charles C.

Simulation and measurement of disturbance propagation in a single tether system

One of the missions of the Getaway Tether Experiment (GATE) is to investigate disturbance propagation and control in a tethered system. In order to understand the nature of the propagation, simulation of the tether response is vital. A single finite duration pulse is the source of the disturbance. A bead model is used to predict the motion of the tether and the end masses (modeled as point masses). System response is checked for different magnitudes of force and for different points of impact on the tether. Along with simulation, hardware development is needed, especially in the area of tension measurement. At this time, hardware is being developed to measure the tension in the tether, so that the tethered system can be controlled via tension feedback. The hardware will then be tested in conjunction with the Dynamics and Control Mission of the GATE project.

Greene, Michael