A passive localization method for stiffened composite structures with a parameterized laminate model

Passive health monitoring in real time is an effective approach to ensure the integrity and safety of aircraft composite structures. A two-step method based on a parameterized laminate model is proposed as a way to locate acoustic sources for laminates with stiffeners: calibration and monitoring, which requires neither prior knowledge of material parameters nor a large number of training samples. In step one, calibration is used to identify material parameters through acoustic emissions at three points with known locations prior to passive monitoring to ensure the accuracy of monitoring. Next in step two, monitoring is used to locate acoustic emission events with the calibrated model from step one. The arrival time of expansion waves extracted by Akaike Information Criterion is used as input features during the two-step method. The effect of stiffened components on the input feature was investigated with finite element methods and experiments. Finally, the proposed method was verified by experiments on an anisotropic stiffened composite laminate as the method was able to locate acoustic sources with high enough accuracy.