An indicator kriging-based framework for multi-damage localization in ISHM

Accurate damage localization remains a critical and challenging task within electromechanical impedance-based structural health monitoring (ISHM), particularly in multiple simultaneous damage scenarios. While numerous methods have been proposed for single-damage localization using electromechanical impedance (EMI) measurements, approaches specifically designed to identify several damage sites remain scarce and underdeveloped. To address this gap, the present study introduces a novel localization framework based on the indicator kriging technique to assess the location of multiple damages. The methodology is experimentally validated using an aluminum plate subjected to up to three concurrent damage scenarios. The influence of frequency interval selection on the performance of the kriging-based probability models is systematically assessed through three distinct frequency band selection strategies. The results demonstrate that the proposed framework effectively identified multiple damage locations with good adherence to the real positions, comparable to or even superior to other advanced methodologies for multi-damage localization. The proposed method advances the current state of the art in multi-damage localization. At the same time, comprehensive experimental investigations offer valuable insights to guide future research efforts toward implementing robust solutions to industrial-scale environments.