Disturbance Observer-based Robust Speed Control of Autonomous In-Wheel Driven Electric Vehicle

Abstract

This paper presents a disturbance observer (DOB) based robust speed tracking control considering tire slip for autonomous electric vehicle (AEV) driven by in-wheel motors. The variation of driving situation brings about the change in the load added to the longitudinal vehicle dynamics. The change is regarded as a disturbance and compensated by the proposed DOB designed with a first-order low-pass Q-filter. Also, maximum transmissible torque estimation (MTTE) is introduced to control the tire slip, thus sufficiently controlling the tire force generated by the motor torque. The tire force is estimated based on the wheel dynamic model satisfying energy function, consisting of vehicle motion variables. The proposed control strategy is validated by vehicle dynamic simulation software Carsim.