Description: IFOS and its research institute collaborator, Washington State University (WSU), have demonstrated feasibility of a structural health monitoring (SHM) system for aerospace vehicles such as Unmanned Aerial Vehicles (UAVs) or commercial airliners. In Phase 1, a unique high-speed, high-channel count fiber Bragg grating (FBG) sensor interrogation system enabling a new Lamb wave-based damage detection method was demonstrated. This SHM system allows accurate detection of damage in rectangular composite plates simultaneously collected from a plurality of strategically placed FBG sensors using relatively few piezo actuators. Utilization of structurally integrated, distributed sensors to monitor the health of a structure allows for high-speed collection and interpretation of sensor signals, coupled with real-time data processing. The proposed system provides automated diagnosis and prognosis capabilities, greatly reducing the overall inspection burden. Phase 2 is designed to advance the technology towards specific NASA flight research testbed platforms, particularly Ikhana. During Phase 2, IFOS will collaborate with prime system contractors to address challenges and risks associated with the intended operational environment, including (a) generation of a complete flight worthy design, (b) performance enhancement and ruggedization of the interrogator and sensors, (c) optimization of damage detection algorithms and their implementation, and (d) total system performance validation and evaluation.

Benefits: For aerospace vehicle health monitoring applications, the integrated, distributed optical sensor-actuator systems developed by the IFOS team will significantly increase the sensing capability as well as extend the applicability of fiber-optic sensors systems at low cost. Further applications include instrumentation for jet engines and flight control systems, oil exploration, marine structures, power plants, and critical infrastructures for homeland security. The IFOS systems will greatly contribute to improved aviation security technologies. IFOS' high-speed, high-resolution and multiplexed sensor systems coupled with advanced SHM techniques are uniquely suited to monitoring the health and real time condition of Air Transportation Systems (ATS). The proposed technology can be readily developed into on-board and real-time monitoring systems, allowing frequent and timely damage detection, security risk assessment and incident precursor identification. Thus, timely preparedness, preventive maintenance or repair activities can be more focused and efficient, enhancing the safety, security and service life of the ATS.

This project has direct NASA applications in the following areas: 1)Real-time SHM for UAVs such as Ikhana, Golfstream and Global Hawk 2)Advanced Technology Composites (ATC) project for Ares V launch vehicle and Crew Exploration Vehicle (CEV) 3)NASA support of Air Transportation Security programs 4)Integrated Vehicle Health Monitoring (IVHM) 5)Automated Nondestructive Evaluation for faulty structural components 6)Flight control System Real-time autonomous sensor validity monitors 7)Monitoring and control of composite structures manufacturing and assembly process 8)Self-monitoring structures with alarm and abort capabilities 9)Pyrotechnic test and data acquisition for shock response spectrum analysis.