Research on formation control method of multi-underwater unmanned vehicle under weak communication conditions

To address the follower’s state acquisition issue during communication intervals under weak underwater communication and improve formation accuracy, this paper introduces a virtual target to establish a dynamic coupling between the leader and the follower. The trajectory mapping characteristics of the virtual target are used to enable the follower to accurately track the desired formation in a nonlinear motion environment, which provides theoretical support and a technical path for complex formation control problems. A trajectory tracking controller is designed by using the filter backstepping method, aiming at the high-order derivative problem in the backstepping method, the virtual control quantity is taken as the input of the second-order filter, the virtual control quantity and its derivative are estimated through the second-order filter, and the estimated value is used as the actual control input of the UUV (underwater unmanned vehicle) and the derivative of the virtual control quantity is obtained by the integration method, which avoids the “differential explosion” phenomenon in the traditional method and reduces the computational complexity. The proposed method effectively resolves communication delays and cycle constraints by considering communication limitations, actuator dynamics, and input restrictions. Simulation results show the controller’s effectiveness and robustness.