FBG sensors have gained increasing importance for structural health monitoring in aeronautics, enabling large-scale measurement of most relevant structural parameters while mitigating technical constrains of conventional sensors. FBG technology application for real-time structural monitoring during flight is currently limited by the lack of flight qualified interrogation equipment.
A first goal of the present proposal was the update of currently existing instrumentation to suit the environmental and operational requiems of in-flight applications, increasing instrumentation reliability, and measurement repeatability and precision. An additional issue that should be solved if this technology is to be employed for in-flight monitoring applications was the issue of equipment interfacing with the on-board avionics. A second objective of the work was the analysis of the possible integration of avionic standards within the FBG interrogation equipment, which will allow for direct interfacing with the on-board avionics. Finally, the suitability of quasi-distributed FBG sensor arrays for whole area damage detection were assessed by the implementation and testing of a demonstrator with more than 100 sensors on a composite structure. Results were compared with other measuring techniques as thermography and ultrasounds.
These objectives were addressed by relying on the team’s strong heritage on Fiber Optic Sensing Technology and on aeronautic applications and testing. FiberSensing’s commercial product portfolio of FBG sensors and interrogation units were the starting point towards in-flight qualification of equipment and to specific FBG array sensor design for composite embedment. INEGI and NDTE’s long experience in testing provided the necessary knowledge in terms of the test design and completion and on the specific requirements associated to in-flight operation.