Abstract
This paper addresses the consensus control challenge for multiple autonomous underwater vehicles’ (AUVs) formation operating under external disturbances and communication delays. A fixed-time disturbance observer (FxTDO) is developed to precisely estimate external disturbances within a fixed time. A fixed-time state observer (FxTSO) is designed to reconstruct the leader’s position and velocity states, effectively compensating for communication delays. Building upon these observer estimates, an event-triggered sliding mode controller is proposed to achieve formation consensus with guaranteed convergence time while significantly reducing communication frequency through its triggering mechanism. The entire approach ensures fixed-time convergence of the closed-loop system, and rigorous theoretical proof of this stability is provided. Simulation results confirm the effectiveness of the proposed scheme in handling external disturbances and delays, achieving accurate formation tracking with improved communication efficiency. This work provides a robust solution for multi-AUV coordination in challenging environments.