Strain Sensor

Fibre optic 3D strain sensor

Aim

New types of fibre optic strain sensors based on fibre Bragg gratings (FBG) for integration into CFRP components.

Contact

Dipl.-Ing. (FH) Simon Kibben (FBG sensors)
Dipl.-Phys. Miron Kropp (data evaluation)

Figure 1
Inscription of Bragg gratings in photosensitive glass fibres using a quartz glass phase mask.

Summary

Conventional, one dimensional fibre Bragg gratings are established in many fields of application such as structural health monitoring (SHM) of CFRP components. At critical points of such structures, like in the vicinity of bolted joints, more dimensional and directionally discriminative strain detection can supply additional hints at existing mechanical damage and remaining lifetime of the laminate. The present project will provide methods for production of 3D fibre Bragg gratings from conventional, commercially available glass fibres. The fibres are locally ground to produce an asymmetric, D-shaped cross section in the area of the actual sensor. Further to the grinding process, a microoptical data acquisition and processing unit will be developed which, as a customized device, combines minimum size and weight.

Keywords

Fibre-Bragg-Gratings, fibre optic sensor, Structural Health Monitoring (SHM), carbon fibre reinforced plastics (CFRP), aeronautical components