A Simultaneous Planning and Control Method Integrating APF and MPC to Solve Autonomous Navigation for USVs in Unknown Environments

This paper is devoted to solving autonomous navigation for unmanned surface vessels (USVs) in unknown environments. To overcome the deficiency of the “first planning then tracking” motion control framework, a novel simultaneous planning and control (SPC) method is developed. The developed method combines an improved artificial potential field (IAPF) and model predictive control (MPC) techniques. Improvements in the IAPF are made to deal with constraints on angular velocity. In each step of the SPC method, the IAPF is used for robust and efficient tracking in a short future. And the MPC is implemented to generate actual control commands for high-precision tracking. The IAPF and the MPC work in an alternative way to drive the USV to the prescribed target while avoiding the obstacles detected around. Simulations with static and dynamic obstacles demonstrate the effectiveness of the proposed method. The method works well when maneuvering in complex environments even crossing narrow tunnels.