Adaptive Backstepping Control for Underwater Robots in Complex Environments

This paper explores the tracking control of an Autonomous Underwater Vehicle (AUV) in challenging ocean conditions. To address disturbances from waves and uncertainties in AUV parameters, a robust adaptive controller is developed. The controller utilizes an adaptive backstepping algorithm to achieve control objectives. The stability of the control law is analyzed using the Lyapunov method, and performance is validated through case studies. The study focuses on tracking control of the AUV in the presence of disturbances, which are modelled as unknown parameters. An adaptive algorithm is used to estimate these parameters, and the backstepping method is employed for system control. The backstepping controller has been implemented to effectively follow reference trajectories and maintain stability of the AUV within their vicinity. The results of the proposed method were compared with those of the sliding mode controller in the scenario of unmodeled dynamics, with the proposed method demonstrating superior performance. Results demonstrate that the adaptive backstepping controller effectively maintains tracking despite disturbances. The study highlights the benefits of incorporating disturbance estimation in underwater vehicle control.