摘要
针对被动空气悬架系统不能很好解决车辆乘坐舒适性和操控稳定性问题,基于空气悬架的非线性特点有针对性的研究主动控制策略,以进一步提高其性能,使车辆在各种路面条件下实现主动调节。开展了大客车用空气弹簧试验,获得空气弹簧的非线性弹性力及非线性阻尼力数据,并在实测数据的基础上,采用MATLAB/Simulink建立了1/4非线性主动空气悬架模型。应用微分几何理论中的输出-干扰解耦方法,通过适当的坐标变换将1/4非线性主动空气悬架模型简化为线性系统并实施线性二次型调节器(LQR)最优控制,尝试将自适应遗传算法应用于LQR最优控制权阵的确定。通过分析主动空气悬架性能评价指标的特点设置适当的适应度函数,再利用自适应遗传算法的全局寻优能力得到最优控制权阵,从而获得非线性主动空气悬架的最优反馈控制力。以模拟产生的不同路面的不平度曲线和不同车速作为激励作用于车辆模型进行仿真试验,并对仿真结果进行了分析。结果表明:设计的基于微分几何理论的最优控制器获得了良好的控制效果,对车身垂直振动加速度、悬架动挠度及轮胎形变的改善效果明显,有效提高了汽车行驶平顺性和安全性。研究结果可为非线性汽车悬架的控制提供理论参考。
Aim at the passive air suspension systems cannot solve the problem of vehicle ride comfort and handling stability well,a targeted active control strategy was researched based on the nonlinear characteristics of air suspension,to improve performance further and realize better adjustment of the vehicles under various road conditions.The bus-with-air-spring experiment was carried out,and the nonlinear elastic force of the air spring and nonlinear damping force data,which was based on the measured data,were obtained.The nonlinear active air suspension model was established using MATLAB/Simulink.The output-interference decoupling method for differential geometry theory was used,1/4 nonlinear active air suspension model was simplified into a linear system using appropriate coordinate transformation,and linear quadratic regulator（LQR）optimal control was implemented.The adaptive genetic algorithm was used to determinethe optimal LQR control matrix.The characteristics of the active air suspension performance evaluation index were analyzed to formulate the appropriate fitness functions,and the adaptive global optimization ability of the genetic algorithm was used to obtain the optimal control matrix.The optimal feedback control of the nonlinear active air suspension was thus obtained.Simulation experiments were carried out on vehicle models with different road surface roughness curves and different speeds as incentives,and the simulation results were analyzed.The results show that the design of the optimal controller based on differential geometry theory obtains good control.The body vertical vibration acceleration,suspension dynamic deflection,and improvement in the tire deformation are evident.This can improve the vehicle riding comfort and safety effectively.The results can also provide a useful theoretical reference for the control of nonlinear automobile suspensions.
作者
赵丹
马建
王建锋
ZHAO Dan;MA Jian;WANG Jian-feng(School of Automobile,Chang＇an University,Xi＇an 710064,Shaanxi,China)
出处
《长安大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2018年第4期102-110,共9页
Journal of Chang’an University(Natural Science Edition)
基金
中央高校基本科研业务费专项资金项目(310832161010)
关键词
汽车工程
空气弹簧
微分几何
自适应遗传算法
仿真
automotive engineering
air spring
differential geometry
adaptive genetic algorithm
simulation
