Dynamics of tunable multistable metastructures

Abstract

Connectivity yields unconventional properties. However, the attainable dynamics are strongly dependent on the unit cell size, restricting the effective behavior to narrow, high-frequencies bands. This is due to the nature of band gaps from local resonance or scattering, both of which are strongly related to unit’s size (mass) and stiffness. We present multistable metastructures displaying strong nonlinear interactions between propagating transition waves and structural modes. We show how transition waves excite the same type of response in the metastructure’s units regardless of the input excitation. This invariant response allows for efficient electromechanical energy transduction as the mechanical response can be tuned to electrical conversion circuits robustly. We also present a new dynamic phenomenon—solitonic resonance—leveraging soliton-structural mode interactions that enable multistable metastructures to exhibit extreme input-output energy exchange. By tuning the topology of our multistable metastructures we can transform energy input frequencies into output responses orders of magnitude apart. The presented metastructures break the dependence of the attainable unconventional dynamical properties on the unit cell's size. The dynamics of multistable metastructure provide a route to accelerating metamaterials adoption in engineering applications addressing the structural bandwidth.