Research on synchronous control strategy of steer-by-wire system with dual steering actuator motors

Abstract

Steer-by-wire (SBW) system with dual steering actuator motors is a novel and potential type of steering system by means of hardware fault tolerant redundancy to enhance the driving safety. The basic control strategy "road feel feedback and steering angle control" has been carried out. Aiming at the non-synchronous appearance of dual steering actuator motors, dual-motor synchronous control employing differential negative feedback method has been proposed to reduce the adverse influence of "servo fight" non-synchronous issue. In addition, considering the existence of unavoidable backlash impact, dual-motor anti-backlash control adopting variable bias compensation current method has been developed to abate the negative effect caused by backlash factors for SBW system, so that the precision of steering implementation for SBW system can be enhanced. The results of simulations and hardware-in-loop experiments are analysed and then the conclusion has been drawn that the proposed control strategy is effective and feasible.