Counting and Sequential Information Processing in Mechanical Metamaterials

Materials with an irreversible response to cyclic driving exhibit an evolving internal state which, in principle, encodes information on the driving history. Here we realize irreversible metamaterials that count mechanical driving cycles and store the result into easily interpretable internal states. We extend these designs to aperiodic metamaterials that are sensitive to the order of different driving magnitudes, and realize lock and key metamaterials that only reach a specific state for a given target driving sequence. Our metamaterials are robust, scalable, and extendable, give insight into the transient memories of complex media, and open new routes towards smart sensing, soft robotics, and mechanical information processing.

Automated summary

This research presents irreversible metamaterials that have an irreversible response to cyclic driving, allowing them to count mechanical driving cycles and store the result. Furthermore, the study extends these designs to aperiodic metamaterials, which are sensitive to the order of different driving magnitudes, and introduces lock and key metamaterials that only reach a specific state for a given target driving sequence. These metamaterials are robust, scalable, and provide insights into the transient memories of complex media, opening up new possibilities for smart sensing, soft robotics, and mechanical information processing.