Prediction of Remaining Useful Life of Rotorcraft Structures with a Fiber-Optic-Based Sensing System and a Unified Damage Mechanism-Based Model

IFOS proposes to develop a fiber-optic-based sensing system and a unified damage mechanism model utilizing an integrated fiber Bragg grating (FBG) sensor system for prediction of remaining useful life of rotorcraft structures. The proposed new rotorcraft damage modeling technique makes it possible to incorporate temperature and acoustic emission (AE) measurements with load tracking techniques for the assessment of accumulated fatigue damage and remaining useful life without requiring prior history or data. The high sensitivity, high accuracy, state-of-the-art FBG sensors will be capable of real-time rotorcraft load tracking, temperature and AE measurements. Such a system is capable of measuring low (Hz) and high (hundreds of kHz) frequency responses that may be explored for detection of incipient damage. In Phase I the IFOS research team will implement such FBGs as ultrasonic sensors to be surface-mounted on the structure-under-test in a fashion facilitating installation and operation in the field. Advanced signal processing and physics-based fatigue damage modeling algorithms, as well as computer models of rotorcraft structures, will be applied for simulation purposes. In Phase II a prototype of an autonomous onboard Integrated Hybrid Structural Monitoring System (IHSMS) will be developed.