EKF and UKF methods for the Acoustic Emission source localization in Concrete

In this paper, two well-known nonlinear Kalman Filtering algorithms are presented to estimate the location of Acoustic Emission (AE) sources in notched concrete specimens: the Extended Kalman Filter (EKF) and Unscented Kalman Filter (UKF). These algorithms take into account uncertainty in time of flight (TOF) measurements and are applied in the case of the wave velocity known. Three-point bending tests have been realized on notched-plain concrete instrumented with a sparse array of piezoelectric transducers to validate the proposed approaches and under crack mouth opening displacement (CMOD) control. Crack evolution is monitored and followed based on the AE source locations maps. A very good agreement is obtained between the localized points and the crack growth. The results obtained by EKF and UKF are evaluated and compared.