The variable steering ratio of steer-by-wire is analyzed in this paper. To improve the defects of traditional control method and increase the steering behavior of vehicle, this paper presents a novel intelligent control approach for steering ratio of steer-by-wire system. For the uncertainty and non-linear characteristic of steer system, the control method of steering ratio based on fuzzy control and fuzzy neural network were researched in this paper. Fuzzy controller of steering ratio was designed. Then the structure and algorithm of fuzzy neural network were researched. The controller of steering ratio was optimized using fuzzy neural network, center value and width of membership function can be adjusted on- line and steering ratio was optimized. Simulation results show that based on the fuzzy neural network control method expanded the vehicle speed scope compared to the fuzzy control method, and satisfied the requirements of ideal ratio. So the method based on fuzzy neural network is more practical and effective.%以线控转向汽车的传动比控制为重点进行研究,提出了传动比智能控制策略,旨在进一步改善系统的转向性能.针对转向系统的不确定性、非线性的特点,在原有基于模型控制方法的基础上,研究了模糊控制和模糊神经网络在传动比控制中的应用；首先利用模糊控制技术设计传动比控制器,然后研究了模糊神经网络的结构和算法,利用模糊神经网络对理想传动比控制进行改进,实现了输入变量隶属函数中心值和宽度的在线调节,进而对传动比进行优化；从仿真结果可以看出基于模糊神经网络的控制方法比单模糊控制扩大了传动比变化的车速范围,更加符合理想传动比的要求,表明基于模糊神经网络控制方法更具有可行性和有效性.
展开▼
