Single critic network based fault-tolerant tracking control for underactuated AUV with actuator fault

This work investigates the fault-tolerant control problem for underactuated autonomous underwater vehicle (AUV), in which the actuator fault is addressed, that is the sophisticated and challenging problem. A single critic network based adaptive dynamic programming (ADP) is employed to construct a novel fault-tolerant control scheme combined with the backstepping method. Firstly, a virtual velocity control vector is designed based on the kinematic model of underactuated AUV using backstepping approach. The virtual velocity control vector is taken as the virtual velocity of the dynamic model of underactuated AUV. Secondly, an error tracking system is constructed to transform the fault-tolerant tracking control problem into the optimal control problem. Then an online policy iteration algorithm is designed based on the estimated system states. Based on Lyapunov approach, the stability of the error tracking system is guaranteed by the proposed controller. Finally, the simulation results are shown to verify the effectiveness of the proposed method in this work.