Event triggered prescribed time trajectory tracking control for unmanned surface vessels with lumped disturbances and prescribed performance constraints

This article proposes a prescribed-time trajectory tracking control algorithm for unmanned surface vessels with lumped disturbances, limited communication, and error constraints, utilizing an event-triggered mechanism. Firstly, we present a prescribed-time lumped disturbances observer to accurately estimate the lumped disturbances, including external ocean disturbances, model uncertainties, and unmodeled dynamics. Then, a prescribed-time prescribed performance function is implemented to achieve guaranteed steady-state performance within a predefined time. In addition, an event-triggered strategy is embedded into the presented prescribed-time control scheme to lessen the frequency of controller signal updates and conserve communication resources. A thorough stability analysis demonstrates that the proposed control scheme is prescribed-time stable, and Zeno behavior can be prevented. Finally, the efficacy and superiority of the designed control strategy are confirmed with numerical simulations.