Development of Interrogators for Multiplexed Bragg Grating Sensors Progress Report

The increasing requirement for efficient and cost effective aircraft fleet management necessitates the integration of on-line health monitoring capability. Such capability must be reliable, robust and must easily respond to the physical and environmental constraints imposed by the aircraft environment. Highly multiplexed fibre optic Bragg grating sensors are assessed to meet this challenging environment. In an effort to develop a suitable small size, rugged, reliable data acquisition (demodulation) system to interrogate these highly multiplexed fibre optic sensors, a research and developmental activity has been initiated. This report documents the progress made towards such development. Preliminary results, demonstrated the suitability of the use of an Arrayed Waveguide Grating (AWG) demodulation system for monitoring five serially multiplexed gratings. The currently experienced limitation of this miniature demodulation system resides in its inability to perform high speed dynamic measurements.