AUV near-wall-following control based on adaptive disturbance observer

When detecting the wall crack, interferences caused by wall effect will significantly increase the difficulty of controlling AUV. This paper focuses on observing and compensating for interferences in the design of the controller. The optimal weight distribution algorithm is proposed to obtain the desired real-time optimal heading, which ensures that the AUV can achieve autonomous following of the wall by adjusting the heading. The backstepping sliding mode controller based on a slow time-varying adaptive disturbance observer (ADO) is proposed, which can effectively observe and compensate for the interference during AUV near-wall following. Results show that the tracking error of the proposed controller can be greatly reduced compared with the PID controller, and the tracking error is significantly reduced compared with the conventional sliding mode controller. The proposed controller can converge fast with small overshoot and stable control effect. The ADO provides strong robustness against interference, such as wall effect. Thus, AUVs can stably perform near-wall-following tasks and capture clear videos.