Estimation of mechanical parameters based on output-only measurements using Kronecker product equivalence and mass perturbations

Abstract

In this article the estimation of mechanical parameters using vibrational output-only measurements due to ambient excitations is elaborated. The estimated mechanical parameters are solely based on measurements. They are equivalent to analytically derived mechanical parameters of models, which are discretized corresponding to the measurement set-up. In comparison to the analytically derived models no prior knowledge (e.g. material properties) is required to apply the methods presented in this paper. The authors discuss two novel estimation methods on the basis of the Kronecker product equivalence and mass perturbations. Afterwards, both methods are compared to well-known modal approaches using real and complex eigenvectors. Finally, the discussed methods are numerically evaluated using simulated and real laboratory measurements of a cantilever steel beam. In these studies the novel Kronecker product based methods have proved more accurate than the modal approaches.