Multiplexed Fiber Optic Sensor System for Structural Health Monitoring of Ships

In Phase I, IFOS demonstrated the feasibility of developing a high-speed, configurable and highly distributed load monitoring system based on fiber-optic sensor technology. Specifically, IFOS demonstrated static and dynamic load testing capability for 50 sensors on a large cantilever beam with 200Hz/sensor sampling using an innovative multiplexing scheme. In Phase II, IFOS will develop and deliver a scaled-up prototype system designed for smooth transition into Navy platforms, to operate reliably with durability in sea environments. The system will monitor a minimum span of 400ft with high sensitivity (<µstrain) and large dynamic range using miniature cost-effective non-intrusive sensors. This reconfigurable, adaptive and scalable system can accommodate 512 sensors with excellent frequency response. The innovative IFOS approach involves a small and rugged interrogator with parallel photonic signal processing using integrated-optics, ruggedized fiber sensing cables with embedded fiber Bragg gratings (FBGs) and advanced algorithms with robust and user-friendly software. Other attributes include EMI resistance, ease of use and low maintenance. Phase II will include testing and delivery of a dynamically reconfigurable fiber-optic sensor system, validation tests conducted with a prime contractor during Option 1, followed by sea trials during Option 2.