Proposal of lateral force observer with active steering for electric vehicle

The motion stability of vehicle depends on yaw-rate and side-slip angle. These variables influence each other, so we applied decoupling control for yaw-rate and side-slip angle for electric vehicle (EV) with active steering and torque difference between left and right in-wheel motors. However the robustness of decoupling control is fragile for road condition. In this paper, we propose lateral force observer (LFO) which is more robust against variation of cornering stiffness. Then we apply LFO and yaw-moment observer (YMO) to our EV with active steering and two in-wheel motors. The results of simulations and experiments show that the proposed method achives better performance than our conventional method.