Real-Time Front-Wheel Drive Torque Coordinated Control for Path Tracking Under Rear-Wheel Adhesion Coefficient Variations

The history of automobiles spans over a century, yet our understanding of vehicle control, especially in preventing accidents, is still evolving. This article investigates the impact of sudden changes in the rear-wheel adhesion coefficients, which can occur due to inconsistent road friction conditions, on vehicle dynamics stability and path tracking. Our study utilizes simulations to analyze vehicle behavior under such extreme conditions and proposes a novel control system that coordinates front-wheel drive torque with steering adjustment for path tracking. This system incorporates an observer that detects changes in tire forces resulting from alterations in road adhesion coefficient. A stability index, derived from the lateral dynamics model and the Lyapunov function, is employed to determine the optimal times for activating or deactivating the control system. The front-wheel drive torque controller is designed with three cascading feedback loops to enhance path tracking precision. We evaluated the effectiveness of this controller through integrated simulations using CarMaker and Simulink. Additionally, we compare our Front-Wheel Drive Torque Coordinated Control (FDTCC) method with a classical Direct Yaw-Moment Control (DYC) method, demonstrating the advancements made in this research.