FEM simulation based adaptive sensors array error compensation method for impact monitoring on stiffened composite structures

Abstract

To eliminate the sensor array based impact localization bias on stiffened composite structures, a finite element method (FEM) simulation based adaptive sensors array errors compensation method for impact monitoring is introduced. Firstly, detailed analysis and comparison discussion about Lamb wave propagation errors between the simple and stiffened plate are provided using FEM simulation, and the gain-phase errors obtained are structured as a array error matrix. Secondly, array error matrix is substituted into the steering vector of standard two-dimensional Multiple Signal Classification (2D-MUSIC) algorithm to compensate the stiffener effect. And then initial estimates of impact could be estimated by the compensated 2D-MUSIC algorithm. Finally substituting these initial estimates, the cost function is minimized by adaptive iterative to calculate the reasonable location of the impact source. The experiments on a carbon fiber composite stiffened plate demonstrate the validity and effectiveness of the proposed method.