四轮线控转向横摆角速度反馈控制策略研究

为了改善传统四轮转向系统的不足,研究了四轮线控转向系统的横摆角速度反馈控制策略。后轮进行横摆角速度反馈使稳态质心侧偏角极小,并且将车辆横摆和侧偏运动解耦;前轮进行横摆角速度反馈,通过调整反馈系数来预定横摆运动的时间常数,增加转向增益,改善横摆角速度的响应特性。阶跃响应和频率响应等的仿真结果表明,提出的四轮横摆角速度反馈控制策略改善了传统四轮转向的不足转向趋势,缩短了反应时间,提高了驾驶员精确控制车辆的能力,从而提高了操纵稳定性。

Research on Yaw Rate Feedback Control Strategy of Four-Wheel Steer-by-Wire System

To improve the defects of traditional Four-Wheel-Steering system yaw rate feedback control strategy of Four-Wheel-Steer-by-Wire system was researched.Yaw rate feedback to rear wheels reduces steady sideslip angle to a very small value and decouples motions of yaw and sideslip;yaw rate feedback to front wheels can prescribe time constant of yaw, increase steering gain and improve responses of yaw rate.Simulation results of step response and frequency response show that presented four-wheel yaw rate feedback control strategy improves under steer tendency of traditional Four-Wheel-Steering,shortens reaction time,enhances the ability of driver to control vehicle accurately and so enhances handling stability.