基于弹性管的光纤布拉格光栅加速度传感研究

Study on fiber Bragg grating acceleration sensing based on elastic tube

为实现光纤光栅加速度测量,提出了一种基于弹性管的两点式封装光纤布拉格光栅(FBG)加速度传感器。首先理论分析了其传感原理,并建立了其响应灵敏度的解析表达式,通过引入加速度理想灵敏度的概念,讨论了此类型加速度灵敏度的频率响应;其次,基于该模型设计了FBG加速度计,实验研究了加速度的幅频响应特性、谐振频率和加速度的线性响应。结果表明:在小于共振频率的低频段具有较好的平坦区,加速度与波长具有较好的线性关系,线性度为99.8%,加速度响应灵敏度为63.0pm/G。实验值与理论值的相对误差为0.98%,实验与理论吻合的较好。

In order to realize acceleration measurement by fiber Bragg grating （FBG）,a kind of two-spot fabrication FBG model based on elastic tube for acceleration sensing is proposed. First, the sensing principle of the model is analyzed theoretically, and the analytical formula of acceleration sensitivity is also established. By introducing the conception of ideal acceleration sensitivity, the response of acceleration sensitivity to frequency is analyzed and discussed. Second, the accelerometer based on the model is de- signed. The amplitude-frequency characteristics, resonance frequency and linear response of the FBC- accelerometer are researched experimentally. Experimental results indicate that it has a good, flat and linear response at frequencies less than the resonance frequency.the linearity is 99.8 %, the sensitivity is 63.0 pm/G,and the relative error is 0.98%. Analytical investigation agrees very well with experimental results.