车辆主动悬架的非线性路面自适应控制研究

NONLINEAR ROAD ADAPTIVE CONTROL OF VEHICLE ACTIVE SUSPENSION

针对不同的路面状况,提出一种车辆主动悬架的非线性路面自适应控制方法。采用增加高低通非线性滤波器的方法,对以车身垂直加速度和悬架动行程为目标的控制函数进行优化处理,并利用多滑模鲁棒控制方法,设计了一种主动悬架的非线性路面自适应控制器。进行了零动力学子系统的稳定性分析及系统频率特性分析,理论分析表明整个系统是渐进稳定的。仿真结果显示,在不同的路面激励信号作用下,都能取得较好的控制效果,与被动悬架相比,大大改善了乘座的舒适性及车辆的操纵性能。

A nonlinear control strategy is proposed to design the road adaptive active suspension.The dynamic model of a vehicle active suspension is set up,and its working feature is analyzed.Then,a low-pass nonlinear filter and a high-pass nonlinear filter are introduced to optimize the objective function which is determined by the car body vertical acceleration and the suspension travel.The road adaptive controller is designed by using multiple sliding mode robust control method.The stability of zero dynamic subsystem and the frequency performance of the system are analyzed.The theoretical analysis shows that the whole system is asymptotically stable,and the simulation results indicate that,compared with the passive suspension,the active suspension,the active suspension controlled with the proposed method can greatly improve the riding quality of vehicles over different road conditions.