Acceleration Slip Regulation for Four-Wheel-Independently-Actuated Electric Vehicles Based on Road Identification through the Fuzzy Logic

In this paper, a novel method is proposed for tire-road adhesion coefficient estimation based on the fuzzy logic theory for a four-wheel-independently-actuated electric vehicle (FWIA EV). In the meantime, the vehicle velocity is estimated by the unscented Kalman filter method, which provides the foundation for real-time slip ratio calculation. A PID controller is further synthesized for Acceleration Slip Regulation (ASR) to derive the output torque of each in-wheel motor through feeding the error between the real-time slip ratio and the optimal slip ratio based on road identification. Finally, the effectiveness of the proposed scheme is validated under opposite roads with full acceleration in simulation, and the results show that the proposed ASR scheme is capable of improving the driving performance of the FWIA EV.