Luo Binbin, Yang Wanmeng, Hu Xinyu, Lu Huafeng, Shi Shenghui, Zhao Mingfu, Lu Ye, Xie Lang, Sun Zhongyuan, Zhang Lin
Appl Opt. 2018 Mar 20;57(9):2128-2134. doi: 10.1364/AO.57.002128.
An equal strength cantilever beam vibration sensor based on an excessively tilted fiber grating (Ex-TFG) with light intensity demodulation is proposed. The basic principles and sensing characteristics of vibration sensing of an equal strength cantilever beam and Ex-TFG, the combination of which is applied into vibration sensing, are analyzed. An Ex-TFG is attached to the middle axis of an equal strength cantilever beam. As the vibration of a piezoelectric ceramic causes the equal strength cantilever beam to deform, the same and uniform deformation also occurs on the Ex-TFG. Experimental results show that when the thickness of the equal strength cantilever beam is 0.3 mm and the Ex-TFG is at transverse electric (TE) polarization state, the sensing performance is the best, with the maximum acceleration sensitivity reaching 81.065 mv·m·s, and the fast Fourier transform (FFT) main frequency components of the sensing signal accounting for more than 80%. In addition, this sensor is stable in sensing performance, easy in demodulation, simple in structure, high in sensitivity, and easy in manufacture, applicable for the sensing and on-line monitoring of low-frequency vibration signals.
提出了一种基于过度倾斜光纤光栅(Ex-TFG)且采用光强解调的等强度悬臂梁振动传感器。分析了等强度悬臂梁和Ex-TFG振动传感的基本原理及传感特性,并将二者结合应用于振动传感。将一个Ex-TFG附着在等强度悬臂梁的中轴线位置。当压电陶瓷的振动使等强度悬臂梁发生形变时,Ex-TFG也会发生相同且均匀的形变。实验结果表明,当等强度悬臂梁的厚度为0.3毫米且Ex-TFG处于横向电场(TE)偏振态时,传感性能最佳,最大加速度灵敏度达到81.065 mv·m·s,传感信号的快速傅里叶变换(FFT)主频分量占比超过80%。此外,该传感器传感性能稳定,解调容易,结构简单,灵敏度高,易于制造,适用于低频振动信号的传感与在线监测。