Three-dimensional path tracking control for an underactuated AUV based on discrete-time sliding mode prediction

According to the model uncertainties problem of an underactuated autonomous underwater vehicle(AUV) and the enviromental current disturbances problem,in order to achieve the three-dimensional path tracking control of the underactuated AUV,the space movement error model is established based on virtual guidance method.The discrete-time sliding mode predictive controller is designed based on recursive sliding mode designing theory.Feedback correction and receding horizon optimization approaches are employed to compensate the in?uence of uncertainties for the sliding mode predictive model.Finally,space curve tracking simulation experiment is carried out by an underactuated AUV.The simulation results show that the designed controller can overcome the in?uence of time-varying nonlinear hydrodynamic damping to the control system,even the proposed control scheme has better effect on attenuating the external current disturbances.Thus the robustness of three-dimensional path following system is guaranteed and the tracking control with high tracking precision can be achieved.