Barvenik Kieran, Bonthron Michael, Jones Anthony, Tubaldi Eleonora
Department of Mechanical Engineering, University of Maryland, College Park, MD, USA.
Nat Commun. 2025 Aug 25;16(1):7922. doi: 10.1038/s41467-025-63072-3.
Cellular metamaterials represent unique platforms to manipulate structure-property relationships and enhance mechanical responses. While their unconventional behaviors have traditionally been obtained via pattern-transformations under compressive loading or deflation, we theoretically investigate and experimentally realize a new class of soft, porous metamaterials that undergo buckling instability upon inflation, unlocking superior programming and sequencing capabilities for soft intelligent machines. Our inflatable metamaterial reimagines the traditional rubber slab with periodic holes by incorporating a single internal pressure cavity. Upon inflation, the structure can be engineered to exhibit global short-wavelength buckling modes with a controllable circumferential lobe count of the cylindrical pores. First, we experimentally demonstrate the programmable post-buckling behavior by tuning the geometric parameters. Then, with a combination of analytical and numerical methods, we accurately predict the critical buckling pressure and pattern reconfiguration of the cellular metamaterial. By enabling different pattern rearrangements of the collapsing pores, we achieve a new actuation mechanism to suddenly reconfigure the global structure, selectively grasp slender objects, and operate multiple fluid channels with a single input.
细胞超材料是操纵结构-性能关系和增强机械响应的独特平台。虽然它们的非常规行为传统上是通过压缩加载或放气时的图案转变来实现的，但我们从理论上进行了研究，并通过实验实现了一类新型的柔软多孔超材料，这类材料在充气时会发生屈曲失稳，为软智能机器开启了卓越的编程和排序能力。我们的可充气超材料通过引入单个内部压力腔，对带有周期性孔的传统橡胶板进行了重新构想。充气时，该结构可以设计成呈现出具有可控圆柱形孔圆周波瓣数的全局短波长屈曲模式。首先，我们通过调整几何参数，实验证明了可编程的屈曲后行为。然后，结合解析和数值方法，我们准确预测了细胞超材料的临界屈曲压力和图案重构。通过使坍塌孔进行不同的图案重排，我们实现了一种新的驱动机制，能够突然重新配置全局结构，选择性地抓取细长物体，并通过单一输入操作多个流体通道。
