四轮独立转向车辆稳定性的模糊最优控制方法  

Fuzzy-optimal Control of Four-Wheel Independent Steering Vehicles

作　　者：金立生[1] 高琳琳[1] 谢宪毅 王发继 李科勇[1] 

机构地区：[1]吉林大学交通学院,吉林长春130022

出　　处：《西南交通大学学报》2016年第6期1064-1072,共9页Journal of Southwest Jiaotong University

基　　金：国家自然科学基金资助项目(51575229)

摘　　要：为改善四轮独立转向(4WIS)车辆的操纵稳定性,在设计了4WIS模型跟踪最优控制器的基础上,对最优控制参数对控制性能的影响以及4WIS车辆转向动力学特性进行了分析,提出了一种基于车辆转向状态的最优控制器参数调整策略,并设计了模糊逻辑控制参数调节器,实现最优控制器参数的自适应调整.结合4WIS车辆的八自由度动力学模型对提出的模糊最优控制系统进行仿真实验分析,结果表明:设计的4WIS模糊最优控制系统能够极大地改善车辆的稳定性与安全性;在高速低附着系数的极限工况下,该系统仍然够能保证车辆的理想转向状态.该系统对于强侧向风一类的侧向干扰具有很强的抑制能力;风速90 km/h的强侧风且无驾驶员干预情况下,车辆在320 m行驶距离内,侧向偏移量仅为0.78 m.A fuzzy-optimal control method was proposed to improve the handling stability of four-wheel independent steering （4WIS） vehicles. Upon completion of the optimal controller designing, the influence of optimal control parameters on control performance and the dynamic characteristic of 4WIS vehicles were analyzed, and a control parameters adjustment strategy based on the vehicle steering state was proposed. By using fuzzy control theory, a fuzzy logic control parameter adjuster was put forward, which can achieve the self-adjustment of optimal control parameters. Simulation experiments were done by using an eight-degree-of-freedom dynamic model of 4WIS vehicle. The simulation results show that the proposed fuzzy-optimal controller can effectively improve the handling stability and safety of 4WIS vehicles. The ideal steering states can be guaranteed even under high speed and low adhesion conditions. Moreover, the proposed controller also provides a good robustness to reject strong cross- wind disturbance, which ensure the vehicle safety under lateral disturbance. In the conditions of strong cross-wind （with a speed of 90 kin/h） disturbance and without driver intervention, the lateral deviation of 4WIS vehicle under the control of the proposed system is only 0.78 m at a driving distance of 320 m.

关 键 词：车辆工程 四轮独立转向 稳定性控制 模糊最优控制 

分 类 号：U461.6[机械工程—车辆工程]