An active disturbance rejection controller for depth-pitch control of an underwater vehicle

This paper proposes an improved active disturbance rejection controller for depth and pitch controls of the autonomous underwater vehicle (AUV). In this new proposed controller, the gain adjustment function is replaced by a hyperbolic tangent function in the extended state observer and its convergence and stability are demonstrated using the lyapunov’s direct method. The proposed controller is used to simulate a 3- DOF underactuated underwater vehicle and the results confirm that this improved active disturbance rejection controller has better performances in diving and hovering period of the AUV than the conventional active disturbance rejection controller. © 2017 ICIC International.