Research on multi-UAV cooperative follow control for tree obstacle-clearing operations

A cooperative formation follow-control method based on a single-leader and multiple-follower structure is proposed to address the problem of insufficient operational accuracy and safety caused by the limited visibility of the leading unmanned aerial vehicle (UAV) during tree-obstacle-clearing operations. The system adopts a leader-follower control strategy and is designed with a two-layer control architecture consisting of an upper cooperative sliding mode controller and a lower trajectory and attitude tracker. For follow-control tasks with fixed desired distance and azimuth, a relative pose and reference velocity model of the follower UAVs is established in the leader’s heading coordinate frame, and a super-twisting sliding mode control law is developed. For three-dimensional azimuth-switching tasks, a polar-coordinate feedforward term is introduced into the reference velocity while the sliding mode control structure is kept unchanged, so that the followers are enabled to perform smooth circular transitions around the leader. Simulation results show that the proposed method achieves high follow-control accuracy, and that the position and yaw errors of the followers converge rapidly during azimuth switching, verifying its effectiveness and applicability in industrial multi-view cooperative operations.