基于对称铰链的中低频光纤加速度传感器及其优化设计

考虑到光纤布拉格光栅(FBG)在振动监测中的 优势,设计了一种基于对称铰链的中低 频布拉格光栅加速度传感器。阐述了传感器的结构和工作原理,并提出了一种拟合的方法计 算铰 链刚度,同时推导出了传感器固有频率和灵敏度的理论公式。采用SQP优化方法以两种不同 的思 路对传感器的结构参数进行优化,得到了两种满足不同需求的传感器尺寸。最后通过在振动 台上 的标定实验,测试了传感器的灵敏度、幅频响应特性和抗横向干扰能力等性能。实验结果表 明, 传感器的谐振频率约为400Hz,灵敏度约为230pm/g,横向干扰小于8%,具备较好的抗横向干扰能力。

Medium-low frequency fiber optic acceleration sensor based on symmetrical gemel and its optimization design

Taking the advantage of fiber Bragg grating (FBG) applied in vibration detection into account, a kind of FBG medium-low frequency acceleration sensor base d on symmetrical gemel is designed.In this paper,the structure and the operation principle of the se nsor are proposed,and a fitting method to calculate the stiffness of gemel is brought up.At the same time,the theoretical formulas of nature frequency and sensitivity of the FBG acceleration sensor are deduced.By optimizing the structure parameter of the sensor in SQP from two different routes,two structure size results that can meet different practical needs are received.At last, in order to verify the accuracy of the theoretical formula,the sensor is tested from three aspects of t he sensitivity,the amplitude-frequency response feature and the transverse anti-interference abil ity through calibration experiment on the vibration table.The experimental results show that the senso r resonant frequency is about 400Hz,and the sensitivity is approximately 230pm/g,which are both fundam entally consistent with the theoretical calculation.What is more,the transverse response amplitude is less than 8%.It shows that the FBG acceleration sensor designed in the paper is equipped with a good t ransverse anti-interference ability.