Dynamic event-triggered impulsive control for prescribed-time trajectory tracking of uncertain underactuated underwater vehicles with input saturation

초록

This paper studies prescribed-time trajectory tracking for uncertain six-degree-of-freedom (6-DOF) underactuated underwater vehicles (UUVs) under intermittent communication and actuator saturation. Unlike existing studies that separately address event-triggered control, impulsive control, or saturation compensation, this paper develops a unified event-triggered impulsive prescribed-time tracking framework for 6-DOF underactuated UUVs with an impulsive saturation-compensation mechanism. Dynamic event-triggering conditions are designed for both the sensor-to-controller and controller-to-actuator channels, ensuring that state transmissions and impulsive control updates are generated only when the corresponding conditions are met. To overcome the nondifferentiability of event-triggered piecewise-constant state signals, an adaptive prescribed-time chainlike filter is introduced to reconstruct the required state information for recursive controller implementation. Based on the reconstructed states, an error-transformation-based impulsive tracking controller is constructed to address the underactuated dynamics. Here, the impulsive saturation compensator compensates for the portion of the desired impulsive correction that cannot be delivered because of actuator saturation, thereby reducing the error accumulation caused by repeated saturation. A Lyapunov-based analysis proves that all closed-loop signals are uniformly ultimately bounded, the tracking error is practically stabilized within the prescribed time, and Zeno behavior is excluded. Comparative simulation results on 6-DOF UUVs demonstrate the effectiveness and advantages of the proposed method.

키워드