Multiplexed fiber Bragg gratings for potential aerospace applications

Fiber optic sensor technology continues to be one of the leading technologies with significant potential for integration into existing and emerging aerospace platforms and systems for advanced in-situ diagnostics, prognostics, health monitoring and management. For the past few years, this technology has witnessed significant development but continues to be limited to trial studies on legacy aircraft. To exploit the full benefits of this promising technology in developing an integrated airframe condition-based maintenance system, several challenges need to be addressed. A major one is the development of lightweight, small size, reliable, robust handheld multisensor interrogation system. This paper highlights our current fiber optic sensor capability; identifies current implementation challenges on aerospace platforms and presents a proposed state of the art alternative. This alternative uses an arrayed waveguide gratings (AWG) based demultiplexer and provides a system resolution of 0.1°C and 1με for temperature and strain monitoring, respectively, in addition to the added benefits of weight and size.