Finite-time composite dynamic compensation control for USVs with rotatable thrusters and multi-channel event-triggered inputs under thruster faults

In the event of thruster faults, this paper investigates the finite-time fault-tolerant control problem of an underactuated unmanned surface vessel (USV) system equipped with two rotatable thrusters under multi-channel event-triggered input conditions. To handle input constraints and control allocation errors caused by partial failures of rotatable thrusters, this paper designs a dynamic compensation controller. The controller improves control accuracy and speeds up convergence under actuator fault coupling. A multi-channel event-triggered control mechanism is also introduced. It reduces unnecessary control updates and lowers network bandwidth consumption. In addition, a finite-time disturbance observer is used to estimate fault-induced and external disturbances. With this observer, the tracking error can converge to a bounded neighborhood within finite time. The finite-time stability and uniform boundedness of the closed-loop system are proved by theoretical analysis. Simulation results show that the proposed method has better fault compensation performance and higher communication efficiency.