Novel Approach for Optimisation of Fibre Bragg Grating Sensor Network for Efficient Damage Detection in Composite Structures

Abstract

With the increased use of fibre reinforced composites in load bearing structures especially in the aerospace industry, it is crucial to have in-situ structural health monitoring systems to ensure safe operation of the structure. When it comes to using fibre Bragg grating sensors for the task, it is not possible to monitor the structure using a single sensor. Consequently, many FBG sensors are needed for monitoring the integrity of a complex composite structure. Randomly placed or uniform sensor networks prevent the optimisation of sensor layout required for efficient detection of damage. In addition, provision for error or insensitivity must be avoided in the process of structural health monitoring.This paper details research work conducted to develop a procedure for optimising an FBG sensor network. Furthermore, procedures for the immediate rehabilitation of FBG sensor networks due to obsolete/broken sensors, has also been investigated. In this study, an artificial neural network (ANN) was developed and successfully deployed to virtually simulate the broken/obsolete sensors in a FBG sensor network. The prediction of the ANN network was found to be within 0.1% error levels.