Hierarchical Fault-Tolerant Control for Lateral Stability of Steer-by-Wire Vehicles

This paper presents a hierarchical fault-tolerant control system design to enhance the lateral stability of steer-by-wire vehicles. The control system can be divided into two layers. The upper layer focuses on designing a controller that determines the desired front steering angle from driver's command to improve lateral stability. The lower layer includes a steering controller that ensures the execution of the desired steering angle from the upper layer. However, the tracking errors of lower layer controller can lead to actuator faults in the upper controller. To address this, we propose a fault-tolerant control strategy for the upper layer. Theoretical analysis and simulation results using Simulink/Carsim demonstrate the effectiveness of the proposed control system in maintaining lateral stability under external disturbance input.