基于波纹管杠杆组合结构的光纤光栅压力传感器设计

针对井中水压高精度测量的需求，基于波纹管的压力传感特性，及悬臂梁的杠杆放大结构，设计了一种高灵敏度的光纤布拉格光栅压力传感器，通过弹性片连接的杠杆结构将压力作用下波纹管的轴向变形放大为光纤布拉格光栅的轴向应变，以实现压力的高精度测量。建立了传感器机械结构的力学模型，推导了传感器中光纤布拉格光栅中心波长变化与压力的数学表达式，并通过有限元方法对传感器的压力灵敏度进行了仿真。该传感器仿真和实验压力灵敏度分别为14.8 pm/kPa和14.1 pm/kPa。该压力传感器能够对小量程范围内的压力进行准确测量，同时可以通过改变杠杆臂长参数改变传感器的灵敏度，调整其测量量程。

Design of fiber Bragg grating pressure sensor based on bellows and lever composite structure

Aiming at the demand of high-precision water pressure measurement in wells, this paper designed a high-sensitivity fiber Bragg grating pressure sensor based on the pressure sensing characteristics of bellows and a cantilever beam-based lever amplification structure. The axial structure of the bellows under pressure is amplified by the lever structure connected by the hinge to the axial strain of the FBG to achieve high-precision measurement of pressure. The mechanical model of the mechanical structure of the sensor is established. The mathematical expression of the wavelength change and pressure of the FBG in the sensor is derived. The pressure sensitivity of the sensor is simulated by the finite element method. The simulated and experimental pressure sensitivities of the sensor are 14.8 pm/kPa and 14.1 pm/kPa, respectively, which are in good agreement. The pressure sensor can accurately measure a certain range of pressure, and by changing the lever arm length parameter, the sensitivity can be changed and the measuring range can be adjusted.