Highly-Multiplexed Fiber-Optic Acoustic Emission Sensor System for Adaptive Structural Health Monitoring
Abstract
Acoustic emissions (AE) are elastic waves in solids generated when elastic energy stored in a material is suddenly released as a result of irreversible transformation in the structure of a material such as from dislocation movement, void formation and coalescence, microcrack initiation and growth, impact events, composite delamination, fiber breakage and fretting, to name just a few. Each such event releasing acoustic energy with a characteristic frequency content. Therefore, AE detection can be a powerful tool for structural health monitoring (SHM). Fiber-optic AE sensors are an emerging technology and, compared to their electronic counterparts, they have many advantages such as small size, light weight, immunity to electromagnetic interference, and multiplexing capability. In the past decade, significant advancement has been made in the development of fiber-optic AE sensor in terms of sensor sensitivity and adapting to dynamic operating environment. However, high-density sensor multiplexing and demodulation with high performance and reasonable cost, characteristics important for practical applications in SHM, are yet to be achieved.The goal of this project is to investigate fiber optic sensors and demodulating approaches that couldultimately lead to the development of a distributed a fiber-optic acoustic emission (AE) sensor system that features high-density sensor multiplexing and a reconfigurable sensor demodulation. This will be achieved by implementing a remote bonding method for AE sensors based on fiberBragg gratings combined with novel sensor design, innovative closed-loop control, and advanced sensor demultiplexing technologies.If successful, the research will enable a distributed a fiber-optic AE sensor system where the sensors are permanently deployed in navy platforms such as ships and aircrafts to form a sensor network to monitor of the health of critical components. Such sensor system can provide real-time, in situ health monitoring during the service and does not affect the operation of the platforms. It will allow us to detect structural flaws and defects in a large area in their early stages. Such capability will greatly reduce the cost of maintenance and repairs and increase the safety confidence levels of Naval platforms.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 26, 2018
- Source ID
- N000141812597
Entities
People
- Ming Han
Organizations
- Michigan State University
- Office of Naval Research
- United States Navy