Impact source localization for composite structures under external dynamic loading condition

This paper suggests a real-time impact localization algorithm for a stiffened composite structure using acoustic emission signals acquired by multiplexed fiber Bragg grating (FBG) sensors. The suggested algorithm requires a database composed of premeasured impact signals at all training points to be used as reference signals. Once the FBG signals were measured from an arbitrary impact event, the root mean-squared (RMS) values were calculated between the obtained signals and all reference signals. Then, the training point that has the minimum RMS values was determined as the resultant impact location. In order to validate the applicability of this algorithm in the external environment, impact localization was performed under a dynamic loading condition. The dynamic loading condition was simulated by exciting the test article using a shaker. The results of validation tests show that the proposed algorithm could successively estimate the impact locations under a dynamic loading condition.