Slip-Regulated Optimal Control for Hybrid-Driven Underwater Hexapod Robot with Thrusters and C-Shaped Legs

The safety of ship hulls, reservoir dams, and bridge piers must be ensured through routine fracture detection and damage repair. An underwater robot with eight thrusters and six C-shaped legs has been built to be able to walk on these intricate underwater structures. In this article, a slip-regulated optimal walking control strategy is proposed while taking into account vehicle dynamics. The controller also produces the necessary longitudinal force and yaw moment, so that the robot follows the desired forward velocity and heading direction. It then equivalently transfers the needed force and moment to the contact points of all supporting legs. The suggested controller also includes appropriate constraints and a cost function to regulate the slippage of supporting legs. In addition to preventing longitudinal slippage and enabling lateral slippage, the proposed control framework enhances walking stability and steering ability. Finally, the effectiveness of the proposed method is verified through the Gazebo platform and the hexapod robot.