Passivity-based stabilizing controller for an underwater robot

This paper introduces an innovative switching control method to stabilize the posture of an underwater robot. The method leverages the passivity property of the robot's open-loop dynamics and factors in inertial effects that could impact its motion. Its primary goal is to guide the robot's position to a user-defined small level set using a potential function, achieved through consecutive switching. Additionally, the method ensures the convergence of the robot's orientation angle to a desired value. By employing a passivity-based switching control approach, the robot alternates between two submanifolds while reducing the potential function during each switch, ultimately leading the robot's position to the potential function's minimum. Through exploiting the passivity property of the robot's dynamics, the method designs a controller to stabilize the robot's posture using a switching strategy guided by the potential function. Results indicate that this method effectively stabilizes the posture of the underwater robot, surpassing conventional control methods in terms of stability and convergence rate.