关键词: 线控转向系统, 路感模拟, 变传动比设计, 参数估计

Abstract:  In steering-by-wire (SBW), as the key execution system of the steer-by-wire chassis, the mechanical connection is replaced by electrical signal which can directly convey the steering operation. The control mode is more flexible, and the modular structure can be realized, which improves the coupling and control freedom between the steering system and other subsystems of the chassis. The two key technologies of steer-by-wire system (road feeling simulation technology and variable transmission ratio technology) and control parameter estimation method are comprehensively expounded. The research results of feedback torque control and return torque control involved in road feeling simulation technology are compared and analyzed. It is pointed out that the decoupling of force transfer characteristics and angular transfer characteristics will cause poor driving experience. The commonly used variable angle transmission ratio design methods are mainly the variable angle transmission ratio with constant yaw rate and the variable angle transmission ratio with the change of vehicle speed (angle). The shortcomings of the single design method are pointed out, and the advantages of the angle transmission characteristic interval satisfying different driver preferences are also clarified. The future research direction and development of steer-by-wire technology are prospected. It is proposed that the development of steer-by-wire technology should tend to be personalized, safe and reliable, and precise control.