Modeling and Design of Integrated 3-D Vector FBG Accelerometer With High Sensitivity

A tailored 3-D integrated accelerometer theoretical model is established, and a corresponding accelerometer with higher sensitivity is proposed and demonstrated experimentally. Based on the idea that the 3-D accelerometer’s three main axes remain highly sensitive and consistent and share one inertial body, a 3-D sensitive and consistent integrated model with high symmetry is established, and a cleverly designed method of encapsulating a fiber Bragg grating (FBG) is sensitive to only one direction. A high-performance accelerometer with higher sensitivity and lower crosstalk has been designed and fabricated. The experimental results obtained show that the bandwidths of the sensor in the X-, Y-, and Z-directions range from 20 to 190 Hz, from 20 to 205 Hz, and from 30 to 205 Hz, respectively, and the sensitivities of the flat range in the X-, Y-, and Z-directions range from 112.5 to 217.0 pm/g, from 104.4 to 207.7 pm/g, and from 98.6 to 198.0 pm/g, respectively. It shows that the parameters of this type of sensor have good consistency in the three directions, which is in line with the design concept. Therefore, this type of sensor has potential theoretical significance and practical application in the field of 3-D signal detection.