TETHER INJECTION OF A SATELLITE INTO A HIGHER ORBIT

摘要

The objective of this paper is to analyze some dynamic aspects of a rotating tether system and to apply the results to the injection of the end satellite into a higher orbit. Considering the whip dynamic as a frame of reference, we use a tether momentum transfer maneuver including retrieval from the orbiter. The TS consist of a massive tether and two masses attached to both tether ends. Assuming an initial state of out of orbital plane motion for the tether system, tether totally deployed and the mass center of the tether system following a circular Keplerian orbit. Then, retrieval process starts from the orbiter. During the retrieval process, the massive tether transfers energy and angular momentum from the system to the satellite, and so, satellite rotates progressively faster. This fact is studied to use, in a controlled way, the accumulated energy in the satellite for lifting it from a lower energy state to a higher one, at expense of the tether system energy. Different tether materials are analyzed in order to determine if they are able to resist the huge tip velocity that may be reached. Differential equations systems that describe the tether dynamic are numerically integrated using Matlab ODE solvers.