Enhancing path following control performance of autonomous ground vehicle through coordinated approach under disturbance effect

Abstract

This study proposes the model predictive control (MPC) with proportional-integral (PI) controller for coordination of active front steering (AFS) and direct yaw moment control (DYC) maneuvers for path following control in an unmanned ground vehicle system. A single-track mode of lateral-yaw motions based on a linearized vehicle model with linear tire characteristics is used for controller design, while the vehicle model used includes roll dynamic motion for the double-track model with a nonlinear tire model. Based on a known trajectory, we tested the vehicle at high forward speed due the fact that the roll dynamic motion will be influenced at high vehicle speed for a double lane change scenario in order to follow the desired trajectory as close as possible, while rejecting the effects of a wind gust. We compared two different controllers; i) MPC with PI of an AFS and, ii) MPC with PI for coordination of AFS and DYC. The simulation results show the proposed coordinated control yielded better tracking performance through high speed maneuvers than AFS maneuvers only. It also demonstrates that the proposed control methods are useful to maintain and enhance vehicle stability along the desired path, and has the ability to eliminate the effect of crosswind.