An FBG-Based 2-D Vibration Sensor With Adjustable Sensitivity

A new fiber Bragg grating (FBG)-based 2-D vibration sensor with adjustable sensitivity has been presented in this paper. The sensor uses screw as elastic body and arranges FBGs in two vertical directions, which can make the sensitivity of the two measurement directions equal to each other and ensure measurement of plane isometric. Four FBGs are used to measure the deflection of the screw tip caused by the combination of fiber and mass rings, which can increase the sensitivity and achieve temperature compensation. The position of the mass rings can be adjusted to achieve adjustable sensitivity. The principle of the sensor as well as modal simulation analyses is introduced. The dynamic and static property experimental analyses of the sensor are proposed. Experimental results show that the sensitivities of the sensor in the X- and Y-directions resides in 16.096 pm/g ~ 152.290 pm/g and 16.398 pm/g ~ 150.680 pm/g, respectively. The flat frequency range is 0-180 Hz.