The Control And Application Of Tethered System

Tethered system is an important technology of astronautics, which is a new domain of space technology in these days. Since the middle of 1970, the theory of tethered system has shown its widely potential application with several decades'development. The technology of tethered system has been one of the most interesting fields of space research in America and Europe. Based on this background, the control and application of tethered system is researched, some new opinions are given and further discussion is performed in this thesis.The main innovative research in this thesis is about the control law of tethered system, the application research of tethered system in rendezvous and docking and the release technology of tethered system. There are detail descriptions of above three questions as follows.Firstly, an ameliorated control law about tether's deployment, holding and retrieval is presented. The control law is one of the most important questions of tethered system. In this thesis, an improved algorithm based on commanded distance and velocity is presented and a further control law of fixed tether distance is performed. Compared with the traditional algorithm the result of the simulation shows that the stable region and the velocity are double enlarged when the length of tether is aptotic and the excessive time of tethered system is five times shorted.Secondly, the rendezvous and docking technology of tethered system is researched. The rendezvous and docking is an important technology of space technology, the security and the flexibility should be improved and R-bar way rendezvous and docking can not come true nowadays.In this thesis, technology of tethered system is used in rendezvous and docking, three V-bar and two R-bar ways are given. The result of research shows that it has good high degree of accuracy, flexibility, much less propellant expenditure, and the security is double ensured.Lastly, the technology of emission or release based on tethered system is performed in orbit. The steady state and quickly rotated release tether programme are presented. The performance of the programme is analysed and majorized. The result of the simulation shows that the middle and low orbit below 4000 kilometers is covered by the technology of emission or release based on tethered system wich has widely potential military application.