基于柔性铰链的光纤光栅二维加速度传感器的优化设计

Optimization Design of Fiber Bragg Grating Two-dimensional Accelerometer Based on Flexure Hinge

为实现对待测表面两个方向的振动监测,基于圆形柔性铰链设计了一种布拉格光栅双向加速度传感器.首先,推导出该传感器的谐振频率及灵敏度的理论公式,然后基于圆形铰链刚度的理论公式,推导并验证了铰链的刚度经验公式.通过MATLAB对传感器的数学模型进行优化设计,得到在满足工作要求时,传感器灵敏度达到最大时的尺寸参数.激振实验结果表明,该传感器的谐振频率约为368Hz,灵敏度约为107.3pm/g,横向抗干扰度为4.8%,谐振频率和灵敏度理论值与实际值的误差分别为-4.2%和7.0%.

In order to realize the vibration monitoring in two directions of the surface,a fiber Bragg grating bi-directional accelerometer is designed based on the circular flexure hinge.First,the theoretical formulas of its resonant frequency and sensitivity are derived.Then,based on the theoretical formulas of circular hinge stiffness,the empirical formulas of hinge stiffness are derived and verified.The mathematical model of the sensor is optimized by MATLAB,and the size parameters are obtained when the sensitivity of the sensor reaches the maximum as the work needs are satisfied.The experimental results show that the resonant frequency is about 368 Hz,the sensitivity is about 107.3 pm/g,and the transverse anti-interference degree is around 4.8%.The error between the theoretical value and the actual value of the resonant frequency and sensitivity are-4.2%and 7.0%respectively.