Emergent reconfigurable mechanical metamaterial tessellations with an exponentially large number of discrete configurations. (November 2020)

• Record Type: Journal Article
• Authors: Yang, Nan; Chen, Chun-Wei; Yang, Jinkyu; Silverberg, Jesse L.
• Is Part Of: Materials & design. Volume 196(2020)
• Publication Date: 2020-11
• Subjects: Metamaterials -- Hierarchical structures -- Structure-property relationships; Materials -- Periodicals; Engineering design -- Periodicals; Matériaux -- Périodiques; Conception technique -- Périodiques; Electronic journals; 620.11
• DOI: 10.1016/j.matdes.2020.109143
• Languages: English
• ISSNs: 0264-1275

Abstract

Abstract: Metamaterials are a class of engineered materials that often violate the routine assumptions that apply to ordinary materials. While metamaterials are typically assembled from carefully designed mesoscale units, the intended bulk-scale functionality can be obscured by unintended emergent effects driven by non-additive unit-unit interactions. These interactions are often sensitive to the number of units and their overall arrangement, making them extrinsic to the unit-scale design. As such, the emergence of extrinsic effects adds a significant hurdle for the development of general-purpose metamaterial technologies. Here, we reconceptualize bulk-scale extrinsic properties as a design opportunity and develop an approach that repurposes them in a new class of exponentially reconfigurable origami-inspired mechanical metamaterials. We illustrate the use of extrinsic properties to design a single general-purpose structure that can be transformed into a variety of passive mechanical devices including a waveguide, a wave lens, and a wave cloak. Bench-top experiments validate the core concepts of our approach and show how unintentional extrinsic effects become useful for applications of reconfigurable metamaterials. Graphical abstract: Unlabelled Image Highlights: Modular metamaterials are proposed with an exponentially large number of configurations. Each unit cell can switch into 4 patterns with multiple acoustic properties. Cellular metamaterial can be in situ set as wave filter, guide, lens and cloak. Extrinsic effect is reconceptualized as a design opportunity to form reconfigurable metamaterials.