汽车线控转向系统路感模拟方法

摘要

For steer-by-wire ( SBW) system removes mechanical linkages between steering system and front wheels, driver is unable to sense road information, a dynamic model of SBW system was established to analyze the road feel theory of vehicle steer system. The road feel control method of SBW system was designed to produce the steering road feel almost the same as that obtained in a conventional electric power steering ( EPS) system. Road feel was computed by rack force of steer system and assist characteristics of EPS system. For rack force was difficult to measure, an algorithm was proposed to estimate rack force by Kalman filter. The test results showed that drivers could effective get road feel information and SBW system could improve the vehicle maneuverability by the proposed road feel control method.%线控转向系统取消了传统转向系统方向盘到转向车轮的机械连接,因而转向路感无法直接反馈给驾驶员,为此通过对汽车转向系统路感的理论分析,建立了线控转向系统动力学模型.采用卡尔曼滤波技术对汽车转向系统齿条受力进行估计,并引入电动助力转向系统的助力特性,设计复制电动助力转向系统路感的线控转向系统路感模拟方法.试验结果表明,路感模拟方法可以使驾驶员获得有效的路感信息,提高了汽车的操纵性和舒适性.