Using boundary conditions for estimation of complex modulus from flexural wave experiments

Estimation of the complex Young´s modulus from transverse wave experiment is considered in this brief. The main goal is to modify the usual least squares estimate so that additional information provided by the boundary conditions can be incorporated in the estimation algorithm. As a result, it is required to solve a constrained nonlinear least squares problem instead of an unconstrained one. The analytical results are validated using experimental data, where the modified estimates outperform the conventional nonlinear least squares estimate by a significant margin.