一种新型滑动杆式光纤光栅振动传感器研究

Study of a novel sliding rod FBG vibration sensor

为了提高振动传感器对加速度信号测量的灵敏度,本文提出了一种新型的基于悬臂梁和滑动杆结合的光纤光栅振动加速度传感器。详细阐述了传感器的结构和工作原理,并推导了传感器固有频率和灵敏度的理论公式。最后通过振动台测试了传感器的固有频率和灵敏度,并和光纤光栅仅沿光纤轴向上受力的实验数据进行了比较。实验结果表明,传感器频率响应曲线的平坦区域在10～38Hz之间,传感器的固有频率为62Hz,灵敏度为52.8pm/g。与光纤光栅仅沿光纤轴向受力的实验相比较,加速度灵敏度提高了70.8%。

In order to improve the sensitivity of vibration sensor in the measurement of acceleration sig- nal, a new type of fiber Bragg grating vibration acceleration sensor based on the combination of cantilever beam and sliding rod is presented in this paper. The structure and working principle of the sensor are de- scribed, and the theoretical formulae of the natural frequency and sensitivity of the sensor are derived. Fi- nally,the natural frequency and sensitivity of the sensor are tested by vibration table. The experimental results show that the wavelength of the fiber Bragg grating changes only in the axial direction, and the flat area of the sensor frequency response curve is between 10 Hz and 38 Hz. The natural frequency of the sensor is 62 Hz and the sensitivity is 52.8 pm/g. Compared with the fiber grating with force only a- long the axis,the acceleration sensitivity is increased by 70.8%.