Acquiring elastic properties of thin composite structure from vibrational testing data

TL;DR

This paper presents a method to determine the elastic properties of thin composite structures using vibrational testing data, employing finite-element analysis and optimization techniques for accurate parameter estimation.

Contribution

It introduces a novel approach combining finite-element modeling with automatic differentiation for efficient and stable identification of elastic parameters from vibrational data.

Findings

Effective parameter estimation demonstrated on simulated data

Insights provided for optimizing experimental design

Stable and efficient gradient and Hessian computations achieved

Abstract

The problem of acquiring elastic properties of a composite material from the data of the vibrational testing is considered. The specimen is considered to abide by the linear elasticity laws and subject to viscoelastic damping. The BVP for transverse movement of such a specimen under harmonic load is formulated and solved with finite-element method. The problem of acquiring the elastic parameters is then formulated as a nonlinear least square optimization problem. The usage of the automatic differentiation technique for stable and efficient computation of the gradient and hessian allows to use well-studied first and second order optimization methods, namely Newton and BFGS. The results of the numerical experiments on simulated data are analyzed in order to provide insights for the experiment planning.