三向光纤布拉格光栅应变传感器的设计及应变特性

Design and Strain Characteristics of Trifarious Fiber Bragg Grating Strain Sensor

针对多向应变测量问题,采用凸台和圆环状基片结构设计了一种三向光纤布拉格光栅(FBG)应变传感器,实现了对结构三个方向应变的同步测量。通过振动试验台和不锈钢板进行了同电阻应变片的静态对比实验和振动监测实验。结果表明,FBG应变传感器和应变片在三个方向的静态应变曲线基本一致,相关系数分别为0.98、0.98和0.99。振动功率谱分析结果表明,FBG应变传感器和应变片均观察到了一次谐波和二次谐波,频率误差分别为2.77%和0.97%,且应变片还监测到了高次谐波信号。该传感器具有结构简单、尺寸小、测量精度高、定位准确等优点,在多向应变监测领域具有良好的应用前景。

Aiming at the problem of multidirectional strain measurement,we design a trifarious fiber Bragg grating(FBG)strain sensor based on a boss and a ringshaped substrate structure.We realize the simultaneous measurement of the strain in three directions of the structure.Static contrast and vibration monitoring experiments with resistance strain gauges were conducted using the vibration testing machine and stainless steel plate.The results show that the static strain curves of the FBG sensor and strain gauge in three directions are the same.Additionally,the correlation coefficients are 0.98,0.98,and 0.99,respectively.The results of vibration power spectrum analysis show that the FBG sensor and strain gauge can observe the first and second harmonics;the frequency error is 2.77%and 0.97%.Furthermore,the strain gauge can detect high harmonic signals.The sensor has many advantages,such as simple structure,small size,high accuracy,and accurate location,having a promising application future in multidirectional strain monitoring.