Fault-Tolerant Prescribed Performance Control Algorithm for Underwater Acoustic Sensor Network Nodes With Thruster Saturation

This paper designs a prescribed performance fault-tolerant control strategy for the underwater acoustic sensor network nodes (UASNN) trajectory tracking control in the presence of ocean current disturbances, modeling uncertainties, and thruster faults. By using a general uncertainties observer, the influence of disturbances and uncertainties are estimated. Additionally, a novel performance function which determines explicitly the maximum convergence time is utilized. Based on the new performance function and corresponding error transformation, the 6-DOF tracking errors are restricted to prescribed bounds to ensure the desired transient and steady response. Furthermore, when considering thruster saturation, we introduce an auxiliary system to compensate for the saturation. The closed-loop system stability is proved by Lyapunov theory. The numerical simulations for three thruster faults are carried out to demonstrate that the proposed strategy is effective.