具有参数不确定性的车辆座椅悬架H_∞输出反馈半主动控制

H_∞ output feedback semi-active control for a vehicle seat suspension with parametric uncertainty

针对座椅悬架系统的参数不确定性和位移测量难题,基于线性矩阵不等式和H∞最优控制理论,建立了座椅悬架系统的参数不确定性H∞输出反馈控制器。控制器利用估计的状态采用鲁棒控制策略计算期望控制力。磁流变阻尼器的控制电压在满足半主动和极值约束条件下,比较期望控制力与当前阻尼力的大小,应用开关控制算法进行调整,使得磁流变阻尼器产生跟踪期望控制力的阻尼力。数值仿真结果证明,该控制器在仅利用座椅架的加速度作为测量输出进行状态估计,以及在座椅悬架系统具有参数不确定性的情况下,仍能有效地对座椅外部激励进行隔振,改善驾驶员的乘坐舒适性。

For the parametric uncertainty and displacement measurement puzzle in a vehicle seat suspension system,based on a linear matrix inequality and H∞ optimal control theory,a H∞ output feedback controller for the seat suspension system subjected to parametric uncertainty was established.This controller produced an expected control force using the states estimated with the measured system outputs.The control voltage of a magneto-rheological damper was adjusted with an on-off control algorithm,the expected control force was compared with the current damping force of the damper under the constraints of semi-active and extremum values,and the damping force of the magneto-rhological damper could track the expected control force well.The numerical simulations results showed that the controller can effectively isolate the seat from external excitations and improve ride comfort,when only the seat acceleration is taken as the measured outputs for states estimation and the parametric uncertainty exists in the seat suspension.