Model Updating of a 3D-Printed Metamaterial Sandwich Dynamic Response

Metamaterials have gained significant attention in engineering applications due to their unique multifield properties and high strength-to-weight ratio. Additive manufacturing methods, such as filament deposition modelling, allow for the production of complex cellular structures, including metamaterial cores with customised mechanical performance. This study explores the dynamic behaviour of a sandwich beam made of aluminum face sheets and a 3D-printed cellular core with oriented hexahedral cells. A high-resolution laser scan is used to reconstruct the beam core geometry and develop a finite element model of the beam. An optimisation algorithm, combining a genetic algorithm and pattern search, is implemented in MATLAB to tune the anisotropic material properties of the model, based on the eigenvector and eigenvalue sensitivities. Numerical modal analysis is conducted using MSC.NASTRAN, while experimental modal analysis provides validation data. The final model accurately predicts dynamic behaviour up to 5000 Hz, providing a solid foundation for future optimisation of metamaterial structures.