为实现磁流变减振器运行中的健康状态监测并满足轿车磁流变减振器控制器阻尼力的需要,设计了一种可同时测量磁流变减振器压缩和复原行程中动态阻尼力的压阻式力传感器。根据汽车磁流变减振器的工作特性和压阻式压力传感器的设计原则,对阻尼力传感器进行了整体结构设计;采用理论计算与有限元仿真相结合的方法,以达到设计量程、获得较大灵敏度和固有频率为设计目标,确定了传感器芯片尺寸;通过分析论证,确定了传感器芯片型式、制作材料;研究了压阻系数与晶向的关系,确定了电阻排布方向和位置、电阻条尺寸、电阻条折弯数,完成了芯片的版图设计。
In order to meet the requirements of health monitoring in the operation of MR dampers and damping force of MR damper controller for cars,a force transducer was proposed based on piezoresistive principles,which might measure dynamic reciprocating damping forces of MR dampers.According to the operating characteristics of the MR dampers for automobiles and the design principles of piezoresistive pressure sensor,the structure of the damper force sensor was designed.Aiming at reaching design range,acquiring high sensitivity and high natural frequency,the size of the sensor chip was determined by the combined method of theory calculation and finite element simulation.The fabrication materials and the measuring circuit were determined through analytic demonstration.The relationship among the coefficients of pressure resistance and crystal orientation,the arrangement direction,the position,the size and the bending number of the resistance were studied before finishing the sensor layout design.