基于系统实时状态观测的车身高度动态调节控制研究

Research on Vehicle Body Height Dynamic Adjustment Control Based on System Real-time State Observation

本文提出了一种基于实时状态观测的车辆车身高度动态调节控制策略,以实现多种路况条件下的车辆高度动态精确控制.不同的道路条件下驾驶员对车辆高度以及姿态稳定性存在不同程度的性能需求,这就需要考虑通过系统外部随机激励来实现车辆高度的动态精确调节与控制.电控空气悬架系统具有非线性特性,仅以悬架动挠度作为参考的车辆高度调节会在随机扰动作用过程中产生极大偏差.因此,本文基于空气弹簧结构与气体流体特性,使用无迹卡尔曼滤波状态观测算法提出了一种悬架静平衡位置观测方法;根据所获知的静平衡位置信息,进一步使用滑模控制算法进行随机激励作用下的悬架高度与车身姿态动态调节.经过模型数值仿真和实车试验验证的结果可知,提出的动态调节控制策略可以实现随机扰动与激励作用下的车辆高度精确控制与车身姿态稳定性保持,从而实现不同道路条件与工况下的车辆综合性能.

In this paper,a control strategy for dynamic adjustment of vehicle body height based on real-time state observation is presented,so as to realize the dynamic and accurate control of vehicle height under various road conditions.Under different road conditions,drivers have different performance requirements for vehicle height and attitude stability,so it is necessary to consider the dynamic and accurate adjustment and control of vehicle height through external stochastic excitation of the system.The electronically controlled air suspension system has nonlinear characteristics.The vehicle height adjustment based on the dynamic deflection of the suspension will produce great deviation in the process of stochastic disturbance.Therefore,based on the pneumatic spring structure and gas fluid characteristics,a suspension static equilibrium position observation method is proposed by using the unscented Kalman filter state observation algorithm;according to the obtained static equilibrium position information,the sliding mode control algorithm is further adopted to dynamically adjust the suspension height and body attitude under stochastic excitation.The results of model numerical simulation and real vehicle experiment demonstrate that the proposed dynamic adjustment control strategy can realize the accurate control of vehicle height and the maintenance of vehicle attitude stability under stochastic disturbance and excitation,so as to ensure the comprehensive performance of vehicle under different road conditions and working conditions.