模型参数摄动下的车辆侧向动力学混沌研究

Chaos study of vehicle lateral dynamics based on perturbation parameter

以车辆多自由度模型为研究对象,耦合轮胎神经网络模型,依据某车型参数及某子午线轮胎在汽车轮胎道路旋转测试台上进行瞬态试验所测得的轮胎接地力数据,构建非线性侧向动力学系统.该系统结构复杂,不易得到解析解,因此借用数值计算方法来研究随着前轮转角和车速变化下的横摆角速度和侧偏角的时间序列内在特性.仿真结果表明,在固定参数下系统具有趋于不动点的稳态响应.当系统参数进行不同频率的周期性摄动时,由计算功率谱、分岔图和最大李雅普诺夫指数图给出了系统稳定和发生分岔的条件和过程及混沌吸引子的特点,为进一步进行混沌控制提供理论参考.

A vehicle model with multiple degrees of freedom is regarded as object of study,which is coupled with tire neural network model.The nonlinear lateral dynamics system is established based on vehicle parameters and the tire data obtained from the transient test on the road rotation test bench.This system has a complicated structure,so it is difficult to obtain the analytical solution.The numerical method can be used to study the intrinsic properties of time sequence of yaw angular velocity and lateral declination with the changes in front wheel angle and the vehicle speed.The simulation results show that this system has a steady-state response tending to the fixed point when the parameters are fixed.Moreover,when system parameters make periodic perturbation with different frequencies,the calculation of power spectrum,bifurcation diagram and largest Lyapunov exponent diagram may provide the conditions and process to keep the system＇s stability and bifurcation.Meantime,the characteristics of chaotic attractor are analyzed,in order to provide a theoretical reference for the chaos control.