Combined relay-adaptive control of flexible spacecraft orientation

Consideration was given to high stabilization of the angular position of the flexible spacecraft with the use of a new physically realizable adaptation algorithm. For the single-loop orientation system with a flywheel-engine, a structure of the combined system was proposed where a subsystem is used to stabilize the elastic oscillations over the intervals of passive motion of the flexible spacecraft within the insensitivity zone of the relay algorithm. A procedure for designing an adaptive algorithm with a reference model based on the direct Lyapunov method was described. Operability of the combined system was investigated using the methods of mathematical modeling.