磁流变减振器集成式压阻加速度传感器设计与试验

Design and Test of Magneto-rheological Damper Piezo-resistive Acceleration Sensor

为满足汽车半主动悬架磁流变减振器运行过程中健康状态监测的需求,提高传感系统的可靠性,设计了一种可以测量动态加速度的磁流变减振器外置集成式压阻加速度传感器。根据减振器的工作特性和压阻加速度传感器的特点,提出了减振器集成加速度传感器的概念,确定了集成方式。分析了集成式压阻传感器的设计原则并对芯片进行了结构选型。为保证传感器具有较大的灵敏度以及较好的动态特性,以测试量程为约束条件,采用理论模型推导与有限元仿真结合的方法,确定了芯片的主要尺寸参数,进一步通过理论分析完成了芯片的版图设计。参照设计的加速度传感器参数,进行了订制,在正弦和随机激励下对采用集成加速度传感器的磁流变减振器的单自由度悬架进行了测试与分析,结果证明所设计的加速度传感器具有较好的精度及动态稳定性,能够满足使用要求。

To satisfy the health monitoring requirements of the on-state magneto-rheological（ MR） semiactive suspension shock absorber and improve the reliability of the damping system,a piezo-resistive acceleration sensor integrated with MR absorber was designed to measure the dynamic acceleration.According to the characteristic of shock absorber and the piezo-resistive acceleration sensor,the concept of integrated acceleration sensor was proposed. Then the design principle of the integrated piezo-resistive sensor was analyzed. Structure selection of the chip was determined on the basis of the principle. In order to ensure the high sensitivity and good dynamic characteristics of the sensor,the main dimension parameters of chip were derived by theoretical analysis and finite element method while the testing range was set as one of the constraints. The layout of the chip,the width and length of the resistor were designed based on the theoretical analysis. Based on the finite element method analysis,the transverse sensitivity was smaller than the vertical sensitivity. Comparing with the vertical acceleration,the effects of transverse acceleration can be ignored. The maximum yield force appeared at the root of beam. Referring to the design requirements,a piezo-resistive acceleration sensor was designed. The single degree of freedom MR suspension with the MR damper integrated acceleration sensor was tested under the sine and random signals. The results showed that the designed acceleration sensor had good precision and dynamic stability which can satisfy the application requirement.