Active steering control system for an independent wheel drive electric vehicle

This research presents an active steering control system (ASCS) for an independent wheel drive electric vehicle (EV). The ASCS will manoeuvre the independently actuated (IA) all-wheel drive (AWD) EV via coordinating the angular velocities of the four wheels plus active front steering (AFS). Due to the physical and mechanical limitations of the steering input in conventional AFS, the differential speed between left and right wheels of an IA EV is used to generate the additional steering effects. The proposed ASCS is a combination of forward speed and yaw rate controllers, designed using the robust H∞ control methodology. The effectiveness of the proposed control system is analysed using a high-fidelity vehicle model by simulating different driving conditions and road disturbances cases. The simulation results indicate that the proposed system can significantly improve the vehicle performance by tracking the desired yaw rate and speed.