Multichannel Optical Fiber Interrogator

To address the Navy?s need for a low-cost, low-power, lightweight, multichannel optical fiber interrogator for structural health management of rotor blades, Physical Optics Corporation (POC) proposes to develop a new Multichannel Optical Fiber Interrogator (MOFIN). This proposed rotor health monitoring technology is based on the use of fiber Bragg grating sensor arrays and a high-speed edge-filtering demodulation method utilizing an arrayed waveguide and an ultrafast optical switch. Specifically, the innovative system design and the use of miniature, low power planar light wave circuit photonic devices and optoelectronic components will enable the MOFIN to measure strains from more than 15 locations in a single blade at a data rate of >5 KHz using less than 3 W power from energy harvesting units. As a result, this fiber interrogator offers a multi-functional, on-rotor, and impact- and usage-degradation monitoring tool which directly addresses the Navy requirements. In Phase I, POC will demonstrate the feasibility of MOFIN by building a benchtop prototype using commercial off-the-shelf components and testing in a laboratory-scale rotor blade test rig. In Phase II, POC plans to build a complete field-ready prototype reaching technology readiness level TRL-5+ and be ready for initial testing in a naval rotorcraft.