Practical Synchronous Steering Angle Control of a Dual-Motor Driving Steer-by-Wire System

Recently, dual-motor driving steer-by-wire (SbW) systems have been introduced and have received considerable attention because they can overcome the limitations of single motor driving SbW systems, which cannot provide large torques required by commercial vehicles and are vulnerable to faults. The two main issues on the performance of the dual-motor driving SbW systems is to ensure steering robustness against model uncertainties, external disturbances, and road condition changes and to synchronize the steering angle. In this paper, a sliding mode controller (SMC) with a disturbance observer (DOB) under master-slave control is proposed to tackle these issues. The combination of an SMC and a DOB is employed to guarantee strong robustness against model uncertainties and external disturbances. In addition, master-slave control is applied to enhance the synchronization performance of dual motor driving SbW systems with significantly different dynamic and response characteristics. Comparative experimental studies are conducted to verify the excellent performance of the proposed control scheme for dual-motor driving SbW systems.