The Output Feedback Of VSC Of The Spacecraft With Elastic Appendiges

With the rapid development of the satellite technique and its widelyapplication, the flexible satellite attitude control is paying more and moreimportant in the high requirements of the satellite's pointing accuracy and itsstability. Consequently, the design and research of the satellite's attitude controlsystem and its simulation become focused naturally. In the thesis, in order todesign the control system of some flexible satellite, firstly, we establish themodel for the simulation system. Based on the models, we design the controlsystem, initially complete tits simulation system according to the above research.The main contents are as follows:First of all, we choose mode truncation method to illustrate the math model,and then we get the kinematical function. By the same time, we analyze theinterferential moment when the satellite in the space, and the math modelfunction is listed accordingly.Afterwards, in the design course of the attitude control system, from thecommon questions of the attitude's control, we discuss the influence of theflexible satellite's numbers of flexibility mode, and at last, we get the functionfor the simulation system. Based on this function, we design the control systemsby PID method, and get the needed modes from the simulation results.Then, we design a variable structure control (VSC) system. The VScontroller has some merits, such as simple construe, easily designed. And it isinsensitive to the change of the parameters, as well as, it has very high robost.But in fact, because the switch performing system has some delay or inertia,inevitably, it will bring some oscillation in high frequency. Base on this resultand the unknown flexible modes, we advance a designing method with outputfeedback variable structure controller, and give out the result of the simulation.Compared with the PID method, we can easily know that the VSC is moreadaptive, such as in the stability, dynamic characteristics and robosts.