Heterogeneous digital stiffness programming

A heterogeneous design of mechanical metamaterial enables digital stiffness programmability. The prototype is composed an elastomer matrix containing diamond-shaped cavities that are selectively confined along their diagonals by semi-rigid plastic beam inserts. Unit-cell perturbations caused insert placement or removal reshape the global constitutive relation, whose lower and upper bounds correspond to configurations with all holes empty inserts in place, respectively, due a gap between moduli. Bidirectional operation accomplished varying orientation inserts, longitudinal increasing macroscopic compression transverse tension. Arranged representations such local states form explicit encoding patterns, allowing both statical situ systematic programming minimal mass changes. These properties establish new paradigm for actively tuning vibration isolation systems response changes base structure’s resonances.