The Research Of Large Angle Maneuver Attitude Nonlinear Control Law For Satellite

Research and simulation experiments based on nonlinear control method of the satellite attitude large-angle maneuver based on reaction wheel are studied in this paper. According to the nonlinear feature of the large-angle attitude maneuver control and the requirement of th e control system , nonlinear theory is taken to design three controllers by the Lyapunov theory, the variable structure control theory and robust adaptive theory.First, attitude maneuvering control system modeled by quaternion instead of Euler angle is put forward, then the error quaternion is taken in consideration for the description of the kinematics model of the satellite. This chapter also gives mathmatical proof to the attitute transition relationship of the space sattellite, which lays solid foundation for further study in this paper.Second, control laws are designed based on the classical Lyapunov method. The global asymptotic stability under such control laws is strictly proved through theorical study. Simulation experiment are carried out under matlab inviroment for different parameters and considering of the unvertainty of the inertia,Finally conclusion is drawn that control law is not dependent on parameters and has high robustness.Third, control law designing method based on variable structure is studied in this paper. This control law uses quadratic optimal method when slecting switching face, which ensures the movement in the euler parameters and angular are optimal for the quadratic index. Meanwhile,the stability of the sliding mode is demonstrated.A sliding mode control law is designed based on general reaching law and the robustness of this control law is analyzed. In order to obtain better performance of the large angle maneuvering of spacecraft, sliding mode control law based on equivalent control method is further designed with the extra help of the jet control. Finally it is shown from simulation that control system has global stability and high robustness. The equivalent control method based variable structure control law has better performance than reaching law based one.Finally, an adaptive robust controller is designed in this paper. First, a control law is designed to ensure the stability of the system. Then the proposed designing algorithm, which combined adaptive back-stepping method with nonlinear damping algorithm, ensures that the parameters of the spacecraft are estimated and the uncertain of disturbance torques was counteracted. Finally, through the simulation of satellite control system the feasibility of the proposed controllers is proved. The design method is simple, the controller can be easily realized, and thus the controller is of great value for the practical application and suits the requirement for engineering application.