Programming Sequences in Multistable Mechanical Metamaterials

Multistability—the property of having multiple stable equilibrium configurations—has recently emerged as a powerful platform to design a wide range of smart structures, including shape-reconfigurable architectures, fully elastic and reusable energy-trapping metamaterials, soft swimming robots with preprogrammed directional propulsion, and deployable solar panels for aerospace applications. Here, we focus on a model system comprising a 1D array of rigid blocks connected by rigid levers and a linear spring and use a combination of experiments and analyses to study the effect of geometric parameters on the deformation sequences that emerge when the displacement of the top unit is controlled. We then exploit these sequences to design a simple machine with programmable behavior.