A robust triaxial localization method of AE source using refraction path

Abstract

Acoustic emission (AE) localization algorithms based on homogeneous media or single-velocity are less accurate when applied to the triaxial localization experiments. To the end, a robust triaxial localization method of AE source using refraction path is proposed. Firstly, the control equation of the refraction path is established according to the sensor coordinates and arrival times. Secondly, considering the influence of time-difference-of-arrival (TDOA) errors, the residual of the governing equation is calculated to estimate the equation weight. Thirdly, the refraction points in different directions are solved using Snell’s law and orthogonal constraints. Finally, the source coordinates are iteratively solved by weighted correction terms. The feasibility and accuracy of the proposed method are verified by pencil-lead breaking experiments. The simulation results show that the new method is almost unaffected by the refraction ratio, and always holds more stable and accurate positioning performance than the traditional method under different ratios and scales of TDOA outliers.