Lane departure assistance based on balanced longitudinal slip ratio differential braking control

This paper presents studies on differential braking-based Lane Departure Assistance System (LDAS). The dynamic threshold of Time to Lane Crossing (TLC), determined by vehicle heading error, speed, road adhesion and reaction time of human-machine system, is studied to activate driving assistance. Based on 2-DOF reference vehicle model and driver preview model, the desired yaw rate to avoid lane departure is calculated. To avoid loss of lateral stability during braking, strategies for the distribution of braking force are developed based on balanced longitudinal slip ratio, which aim to limit the slip ratio on all wheels. The Hardware in Loop (HIL) test bench is established to evaluate the rapid prototyping of LDAS. Results show that the proposed methods can confine the vehicle in lane effectively with lateral stability maintained and operate robustly, benefiting from timely assistance, model-independent control algorithm, and small and balanced slip ratio.