光电工程, 2017, 44 (6): 626, 网络出版: 2017-11-27
可调量程拉绳式光纤布拉格光栅位移传感器
Adjustable range draw-wire type fiber Bragg grating displacement sensor
光纤布拉格光栅 悬臂梁 位移传感器 可调量程 fiber Bragg grating(FBG) cantilever beam displacement sensor adjustable range
摘要
为了解决在复杂电磁环境下大位移量的监测问题,实现对大型机械和工程结构健康安全状况的实时监测,设计了一种基于悬臂梁结构的可调量程拉绳式光纤布拉格光栅位移传感器。悬臂梁两侧对称粘贴了两个不同中心波长的光纤光栅,当悬臂梁自由端的位置发生变化时,两个光纤光栅分别受到拉力和压力,因此光栅的中心波长向相反方向漂移。通过对两个中心波长差值与位移量关系的标定,可以排除温度的影响,实现对位移量的测量。传感器采用了拉绳式的位移传递方式,使得传感器的安装位置及测量方式更加灵活;便于拆装的位移转换装置,可以方便地调整传感器的量程,使其具有更广泛的适用性。位移传感实验结果表明,在传感器量程为60 mm时,位移传感器的平均灵敏度为47.7 pm/mm,相关系数达到0.998,重复性误差为2.83% FS,迟滞误差为1.02% FS。该位移传感器具有结构简单、量程可调的特点,可以满足不同环境下的位移测量需求。
Abstract
In order to solve the problem of displacement monitoring of health monitoring system in the complex electromagnetic environment, and realize the real-time monitoring of large mechanical and engineering struc-ture health and safety conditions, a novel fiber Bragg grating displacement sensor based on the structure of the cantilever beam is designed. Two fiber gratings with different central wavelengths are symmetrically pasted on the both sides of the cantilever beam. When the free end of the cantilever beam is changed, the two fiber grat-ings are respectively subjected to tension and pressure, which leads to the drift of the gratings center wavelength to the opposite directions. Through demarcating the relationship between the two center wavelength difference and displacement, it is possible to realize the measurement of the displacement. At the same time, the problem of cross sensitivity between temperature and displacement is solved. The sensor adopts draw-wire type dis-placement transmission mode, which makes the sensor installation location and measurement method more flexible. In addition, a smart device used to change the measuring range of the sensor is designed and it is also easy to be assem-bled and disassembled, so the whole sensor can be widely used. The experimental results show that when the range is 60 mm, the average sensitivity of the displacement sensor is 47.7 pm/mm,the correlation coefficient is 0.998, the repeatability error is 2.83% FS and the hysteresis error is 1.02% FS. The displacement sensor is char-acterized by simple structure and adjustable range, which can meet the demands of displacement measurement under different environments.
张燕君, 田永胜, 付兴虎, 毕卫红, 张亦男, 王会敏. 可调量程拉绳式光纤布拉格光栅位移传感器[J]. 光电工程, 2017, 44(6): 626. Yanjun Zhang, Yongsheng Tian, Xinghu Fu, Weihong Bi, Yinan Zhang, Huimin Wang. Adjustable range draw-wire type fiber Bragg grating displacement sensor[J]. Opto-Electronic Engineering, 2017, 44(6): 626.