Adaptive Mechanical Metamaterials with On‐Demand Binary Local Modulus for Embodied Intelligence

Biological materials in nature are inherently adaptive, evolving through continuous interaction with their environment. Achieving such adaptability and self‐optimization in artificial materials remains a major challenge. In this work, a simple yet robust mechanism is introduced that enables instantaneous changes in local stiffness components in response to strain. This is realized by designing binary meta‐capsules with two discrete states 0 and 1, each corresponding to a different modulus in one direction. These strain‐responsive capsules switch states based on applied deformation, serving as the building blocks for a new class of adaptive mechanical metamaterials (AMMs). Computational tools are developed to guide the design, and selected structures are fabricated via multi‐material polymer jetting. Mechanical experiments, including compression and indentation tests, confirm the functionality of the AMMs. Because the stiffness change in each meta‐capsule is reversible, the material can reconfigure itself after loading‐unloading cycle. This enables AMMs to dynamically adjust their local properties based on external loads and/or constraints, effectively “reprogramming” or redesigning themselves post‐fabrication, paving the way for transforming 3D/4D printing into adaptive, “infinity‐D” printing.