Use of Optical Fibers for Structural Health Monitoring of Aircraft Components

Abstract

Structural Health Monitoring (SHM) systems for composites are being developed to improve the in-flight monitoring and safety of new aircraft structures. One of the emerging techniques for SHM which is becoming popular in the aircraft industry involves the use of optical fiber sensors due to their ease of integration, resistance to electromagnetic interference and low signal attenuation over long distances. This thesis describes a validated technique for optical fiber embedment and extraction of data from optical fiber data to measure strain.In this research, a novel method to address ingress/egress points of optical fiber has been developed; a surface mounted component has been designed and manufactured using rapid prototyping for the protection of embedded optical fibers at the ingress/egress points. This single component can provide safety and integrity to optical fibers during manufacturing as well as cutting operation. The thesis also focuses on the study of mechanical strength of composites with embedded optical fibers.Composite panels were manufactured with integrated optical fibers using Vacuum Assisted Resin Transfer Molding. Tensile, flexural and impact tests were conducted on these coupons and their results were compared to identify any effects of the embedded fibers on the part performance. Finally, strain experienced by the material while it was in loading and unloading condition was calculated using integrated optical fiber sensors and the values were compared with extensometer data.iii