Self-Contained, Miniaturized, Robust, High-Speed Fiber Bragg Grating Sensor Interrogator

Safety and reliability of ordnance, such as that in solid rocket motors, requires determination of system integrity. To achieve this, a need exists for embedded sensors to provide real-time high-speed indication of system health. Optical Fiber Bragg Grating (FBG) sensors are the most promising types of sensors for dynamic strain measurements due to their light weight, small size, immunity to electromagnetic interference and multiplexibility. However, commercial FBG sensor interrogators are too heavy and large to be deployed in such applications. Based on years of experience and innovations in FBG sensor systems, IFOS proposes a novel miniaturized FBG sensor interrogator with low power consumption to be incorporated into tactical solid fuel rocket motors. It will be capable of interrogating a single optical fiber containing well over five sensors based on commercially available FBGs, under 0.25 pounds in weight and 5 cubic inches in volume, involving no moving parts. The interrogator will operate over the C (extendable to C+L) wavelength band(s), with resolution of 1 pm, dynamic range of 4000+ microstrain per sensor and speed over 5 kHz per sensor. Implementation will be primarily based on well-tested long-lifetime and highly reliable commercially available components.