Fluidic control programming for 3D magnetic soft metamaterials with reconfigurable mechanical behaviors

Active mechanical metamaterials are an attractive proposition for soft robotics, electronic devices, and biomedical devices. However, the utilization of their uncommon physical and mechanical behaviors remains underexplored because existing fabrication processes limit the decoupling of structural frameworks from the responsive mechanisms. Here, we propose a multi-step fluidic control programming strategy by fabricating three-dimensional (3D) magnetic soft materials (MSMs) with reconfigurable mechanical metamaterial behaviors, enabling magnetic-field-driven alteration between three different geometry modes in a single structure. The MSM lattices exhibit fast 3D transitions between positive (ν_max = 3.41) and negative (ν_max = −2.64) Poisson’s ratios. We then create MSMs with reconfigurable orthotropic behaviors, which demonstrate the positive and negative Poisson’s effect in perpendicular planes. In further demonstrations, the fast and wireless response is validated by manipulating falling loads and switching the states of electrical circuits. This research provides a controllable workflow for future magnetic soft metamaterials.