Station-Keeping Control of AUV Based on Visual Servo Under Unknown Disturbance

Nowadays, autonomous underwater vehicles (AUVs) have found new applications in submarine cable inspections or maintenance of underwater facilities. To carry out these tasks, AUVs often rely on station-keeping capabilities to maintain stability at specific positions near the targets, enabling close-up observations, data collection, position marking, and even operational repairs. In response to the potential loss of targets from the camera field of view during AUV station-keeping under unknown disturbances, this article proposes an improved linear active disturbance rejection control (LADRC) algorithm for station-keeping based on visual servo. The improved algorithm utilizes the observed velocity for disturbance trend prediction and timely compensation, thereby enabling the AUV to move quickly in the opposite direction of the external disturbances and regain the lost visual target. Simulation and tank test results confirmed the superiority of the proposed method over proportion integration differentiation and conventional LADRC algorithms, demonstrating its ability to address the issue of visual target loss caused by unknown disturbances.