@techreport{eprints3120,
     institution = {IMT Institute for Advanced Studies Lucca},
            type = {Working Paper},
       publisher = {arXiv},
          author = {Andrea Bacigalupo and Marco Lepidi and Giorgio Gnecco and Luigi Gambarotta},
           title = {Optimal design of auxetic hexachiral metamaterials with local resonators},
            year = {2015},
             url = {http://eprints.imtlucca.it/3120/},
        abstract = {A parametric beam lattice model is formulated to analyse the propagation properties of elastic in-plane waves in an auxetic material based on a hexachiral topology of the periodic cell, equipped with inertial local resonators. The Floquet-Bloch boundary conditions are imposed on a reduced order linear model in the only dynamically active degrees-offreedom. Since the resonators can be designed to open and shift band gaps, an optimal design, focused on the largest possible gap in the low-frequency range, is achieved by solving a maximization problem in the bounded space of the significant geometrical and mechanical parameters. A local optimized solution, for a the lowest pair of consecutive dispersion curves, is found by employing the globally convergent version of the Method of Moving asymptotes, combined with Monte Carlo and quasi-Monte Carlo multi-start techniques.}
}