自传感磁流变半主动悬架滑模观测及控制

Sliding Mode Observation and Control for Semi-Active Suspension Based on Self-Sensing Magnetorheological Damper

针对自传感磁流变半主动悬架系统控制问题,建立了1/4悬架系统动力学模型,采用滑模变结构方法设计了基于相对位移自传感的半主动悬架状态观测器与控制器。首先对系统状态方程进行重构,设计了状态观测器,通过簧上、簧下质量相对位移自传感信息,对系统状态变量进行准确估计,然后以二阶天棚阻尼系统为参考模型,对磁流变半主动悬架进行了滑模控制。仿真结果表明,状态观测器具有很好的估计精度,能有效跟踪系统状态,基于状态估计的滑模控制器能显著改善汽车舒适性,对系统参数变化具有高度的鲁棒特性。

A semi-active suspension based on self-sensing magnetorheological damper is highly integrated, safe and reliable. However, since the signals from the self-sensing device are always very limited, most of conventional control approaches are not applicable. In this paper, the sliding mode varying structure control theory was used to design tile sliding mode observation and controller of the semi-active suspension with self sensing magnetorheological damper based on one quarter vehicle model. As some necessary signals can not be directly measured from the self-sensing magnetorheological damper, the sliding mode observation was designed by rebuilding the system state equation, which makes it possible to obtain some other system state variables fi＇om the relative displacement signal between sprung and unsprung mass. The second-order skyhook model was used as the reference model in the sliding mode control. The simulation results indicate that the sliding mode observation is able to track system state variables accurately and the proposed sliding mode controller can improve tide suspension performance significantly and increase the ride comfbrt and handling perfbrmance of vehicle. Meanwhile, it has also a high robustness to the parameter variation in the suspension system.