Backstepping adaptive docking control for a full-actuated autonomous underwater vehicle with onboard USBL system

The acoustic docking control problem is investigated for the fully-actuated autonomous underwater vehicle (AUV) equipped with the USBL transceiver, which provides the positions of the two transponders on the dock station. Similar to the image-based visual servo control technology, the dynamics of the transponders´ positions is modeled with the AUV´s linear and angular velocities as the control inputs. The docking control errors are defined with the coordinates of the transponders in the local body-fixed frame. The backstepping based adaptive control is utilized to ensure the docking errors to be asymptotically stable with feedback control and adaptation laws. The performances of the proposed docking control are examined by the simulation studies.