Sliding Mode Prediction Control for 3D Path Following of An Underactuated AUV

Abstract

Compared to the traditional 2D path following case, 3D path following is more complicated since the coupling effect between horizontal and vertical plane has to be taken into account. In this paper, a sliding mode prediction controller is presented, which drives an underactuated AUV to follow a desired 3D path under time-varying current disturbances. A sliding mode technique combined with the predictive control strategy is developed to compensate for the impact of the hydrodynamic damping coupling via the feedback correction and receding horizon optimization techniques. In addition, Different from the traditional reference orientation method for path following control, here a methodology named 3D virtual guidance orientation (VGO) is built to deal with the vehicle dynamics. The geometric characteristic of tracking curve is contained in the control design as an extra degree of freedom to drive the vehicle to track a virtual target along desired path. Hence, the proposed method can avoid saturation problem of driving devices (stern plane and rudder) of AUV. Numerical simulations illustrate the excellent path following performance of the AUV in 3D under the proposed control scheme.