Algorithm of adaptation in the attitude control system of a flexible spacecraft

The problem of designing of an adaptive and high-accuracy control system for orientation of flexible spacecraft (FS) is considered. It is assumed that control is a relay one. In this case elastic oscillations of spacecraft flexible elements are the most dangerous from the viewpoint of control system stability. Also it is assumed that for control only limited information about object’s co-ordinates can be used and the FS mathematical model is nonstationary and (or) badly defined. It is presented the procedure of the synthesis of the adaptive control algorithm with reference model that is based on Lyapunov’s method. The structure of a combined control system is suggested. It has a subsystem of the elastic oscillations damping during the intervals of the FS’ passive motion that correspond to the dead zone of relay control algorithm. The computer simulation results illustrating workability and control quality of combined adaptive system are described.