Study on the Active Steering System with Direct Yaw-moment Control for Electric Vehicle with Electric Motored Wheels

This article presents a novel active steering control strategy with direct yaw moment control rather than the steering angle of the front wheels for electric vehicles with electric motored wheels to help the vehicle follow the ideal path when it is understeering. As a feature of this control strategy, the ideal path is acquired by the route planning system, which will be converted into the ideal yaw rate of the vehicle. According to that, a sliding mode controller is developed to calculate the differential drive torque of the two rear wheels to make the yaw of the vehicle meet the expected yaw rate. Given the condition that the vehicle is understeering while the steering angle of the driver is random, the extreme condition, namely when the steering angle of the front tire is zero, is used to verify the feasibility of the proposed system.