Vibration Sensing Characteristics of Reflection-Type Excessively Tilted Fiber Grating Cantilever

A vibration sensor based on the reflection-type excessively tilted fiber grating (ExTFG) cantilever is proposed in this work. The bending strain characteristics and vibration sensing principle of ExTFG arc theoretically analyzed, and a finite element model is constructed by ANSYS to analyze the modality and resonance characteristic response of the sensor. The dynamic response characteristics of bending vibration of the sensor under the periodic load arc studied experimentally. The results show that the vibration sensor based on the reflection-type ExTFG cantilever exhibits a good dynamic response to the acceleration continuous excitation signal. The natural frequency of the sensor can be changed by adjusting its length. The sensor has a good linear response in the range of 1-5g, and its maximum acceleration sensitivity is increased by about 2.5 times compared to the transmission -type ExTFG vibration sensor. The maximum acceleration sensitivity of the transverse electric mode and transverse magnetic mode reaches 0.3 V/g and 0.26 V/g, respectively. In addition, the size of the sensor probe is small enough, and the ExTFG is used as the sensitive unit without additional packaging, so it has potential value in practical applications.