3D heuristic path following for under-actuated autonomous underwater vehicle with bounded controls and control rates

This paper addresses the problem of three dimensional (3D) path following control for an under-actuated autonomous underwater vehicle (AUV) with bounded controls and control rates. In order to prevent out-of-range control inputs from generating and acting on actuators of the AUV, 3D Line-of-Sight (LOS) guidance law and a heuristic bounded controller are applied to the control system. First, the desired pitch and yaw angles are derived from LOS guidance law in kinematics. And then, the desired pitch and yaw angular velocities are obtained based on Lyapunov stability theorem. Subsequently, a model-independent heuristic controller is designed in kinetics to force the steerable velocities of the AUV with actuator saturation to attain their desired profiles, such that the AUV converges to and follows the desired path with its resultant velocity aligned with the tangent of the path. Finally, simulation cases illustrate the satisfactory performance of the proposed control framework as well as heuristic controller subject to actuator saturation.