Acoustic Emission (AE) Distributed Crack Initiation and Growth Monitoring System Using Optical Fibers

The proposed effort will examine continuous AE monitoring of fatigue in aircraft, where uncertainty about fatigue damage threatens to retire aircraft. Noise levels and other common AE issues have been addressed by others, but fundamental limitations of commercial systems, such as weight and EMI interference, continue to hamper extensive use of AE monitoring on aircraft. During Phase I, TRI/Austin will team with Boeing. SPEC, and Felicitv Group to create a smart, single cable AE sensor system that processes AE waveforms at the sensor. This will greatly reduce the amounts of data that commercial systems must transfer via cables into a central computer. This reduction will allow a single cable to monitor many AE sensors while reducing the weight, heat generation and size of the computer. Processing data at the sensor will allow heavy, EMI susceptible pre-amps to be removed from the AE sensors. The smart sensor could be smaller than conventional sensor/preamp combinations because the chips needed to implement smart sensors are commercially available, small, and lightweight. Phase I tasks will include: smart sensor development; fiber optic data transfer system implementation; adapting software; and optimizing ssystem performance versus commercial AE equipment.