Novel Path Following for a Four-Wheel Steering Vehicle Based on Model Predictive Control

Path following is a crucial technique for ensuring the safe and efficient operation of automatic electric vehicles. Four-wheel steering (4WS) technology is known to enhance the accuracy and flexibility of such vehicles. In this paper, we propose a new constrained model predictive control (MPC) based method for path-following, specifically for 4WS vehicles. To simplify the 4WS vehicle kinematics model, we use the assumption of pure rolling and simplify it to a single-track model. We employ a high-precision linearization transformation to convert the nonlinear kinematics models to a linear control-state system. Subsequently, we design a new objective function based on the tracking error model, and formulate the control problem as an optimization problem. Finally, we convert the optimization problem into a quadratic programming (QP) form with constraints that are suitable for real-time applications. We demonstrate the effectiveness of our proposed control method through simulation experiments.