Fig. 1. Physical picture of the FBG sensor

Fig. 2. Three-dimensional model of the FBG sensor

Fig. 3. Section size of the FBG sensor

Fig. 4. Schematic diagram of the ends-bonding of FBG sensor

Fig. 5. Schematic diagram of sensor micro element section

Fig. 6. Force distribution of the FBG section

Fig. 7. Force distribution of the bonding layer

Fig. 8. Meshing of the senser. (a) Global mesh; (b) locally enlarged mesh

Fig. 9. Schematic diagram of constraints and loads applied by the sensor

Fig. 10. Deformation distribution of the matrix layer

Fig. 11. Deformation distribution of the matrix layer at the joint with the bonding layer

Fig. 12. Relationship between the average strain at the bonding point of the matrix and the average strain of the matrix layer

Fig. 13. Influence of elastic modulus of bonding layer on average strain transfer rate of sensor

Fig. 14. Influence of Poisson's ratio of bonding layer on average strain transfer rate of sensor

Fig. 15. Influence of the distance from FBG to the bottom of bonding layer on average strain transfer rate of sensor

Fig. 16. Influence of bonding layer length on average strain transfer rate of sensor

Fig. 17. Deformation distribution of the sensor. (a) Deformation distribution of the FBG; (b) deformation distribution of matrix layer

Fig. 18. Comparison between theoretical solution and simulation solution. (a) Elastic modulus of the bonding layer; (b) Poisson's ratio of the bonding layer; (c) distance from the FBG to the bottom of the bonding layer; (d) length of the bonding layer