Neural adaptive attitude tracking controller for flexible spacecraft

This article presents a neural network adaptive controller for attitude tracking of flexible spacecraft in situations when there exist inertial matrix and external disturbance. In this approach, neural network technique is employed to approximate the unknown system dynamics with finite combinations of some basis functions, and a robust controller is also designed to attenuating the effect of approximation error, more specially, the knowledge of angular velocity is not required. In the closed-loop system, Lyapunov stability analysis shows that the angular velocity trajectories asymptotically follow the reference output trajectories. Finally, simulation results are presented for the attitude tracking of a flexible spacecraft to show the excellent performance of the proposed controller and illustrate its robustness in face of external disturbances and unknown dynamics.