Constrained attitude control of flexible spacecraft with external disturbances and stochastic uncertainties on SO(3)

Abstract

This paper addresses constrained attitude control problems of flexible spacecraft on SO(3) subject to external disturbances and stochastic uncertainties without modal variable measurement. To handle the attitude constraints, an artificial potential function (APF) is constructed based on the rotation matrix. By combining the adaptive super-twisting control technique and the APF, an adaptive robust control law is proposed to achieve constrained attitude control of flexible spacecraft without prior information on the bound of the norm of flexible vibration and external disturbance. The results are then extended to the case that stochastic uncertainties exist and the adaptive robust control law is modified by designing a Lyapunov-function-based control parameter. Numerical simulations are presented to demonstrate the effectiveness of the proposed control laws.