Mechanical metamaterials and beyond

Abstract

Mechanical metamaterials enable the creation of structural materials with unprecedented mechanical properties. However, thus far, research on mechanical metamaterials has focused on passive mechanical metamaterials and the tunability of their mechanical properties. Deep integration of multifunctionality, sensing, electrical actuation, information processing, and advancing data-driven designs are grand challenges in the mechanical metamaterials community that could lead to truly intelligent mechanical metamaterials. In this perspective, we provide an overview of mechanical metamaterials within and beyond their classical mechanical functionalities. We discuss various aspects of data-driven approaches for inverse design and optimization of multifunctional mechanical metamaterials. Our aim is to provide new roadmaps for design and discovery of next-generation active and responsive mechanical metamaterials that can interact with the surrounding environment and adapt to various conditions while inheriting all outstanding mechanical features of classical mechanical metamaterials. Next, we deliberate the emerging mechanical metamaterials with specific functionalities to design informative and scientific intelligent devices. We highlight open challenges ahead of mechanical metamaterial systems at the component and integration levels and their transition into the domain of application beyond their mechanical capabilities.

Lattice Architectures for Thermoelectric Energy Harvesting

“…Other forms of bioinspired lattices such as honeycombs and nacre can also give rise to re-entrant honeycomb metamaterials or nacre-like composite metamaterials . These lattice structures create opportunities for lightweight, high-energy absorption, high-strength, and sound absorption engineered materials. − These metamaterials serve to increase the mechanical characteristics of engineered tools and have been reviewed by several groups. − …”

Maximizing Triboelectric Nanogenerators by Physics‐Informed AI Inverse Design

“…For example, mechanical metamaterials, manmade structural materials assembled by numerous microstructures in a periodic manner, have recently been applied in TENGs to promote the electrical performance due to their structural programmability. [11,114,115] Figure 5d demonstrates the inverse design on the contact interfaces of TENGs by physical patterning based on Maxwell's equations in theoretical analysis. [58] b) Framework of the physics-informed DL for solving an elasticity problem in conductive materials.…”

Pneumatic elastostatics of multi-functional inflatable lattices: realization of extreme specific stiffness with active modulation and deployability

“…Artificially engineered materials can achieve a wide range of tailor-made multi-functional abilities which may not always be available in naturally occurring materials [1][2][3][4][5]. Their micro-scale design can present unprecedented and unconventional, yet useful, properties like ultra-lightweight characteristics [6][7][8][9], shape programming [6,10], crushing resistance and high specific energy absorption [11][12][13][14], auxetic properties [15][16][17][18][19], negative elastic moduli [20][21][22], meta-fluid characteristics [23,24], negative mass density [25,26], tunable wave propagation characteristics and vibration control [27][28][29], programmable constitutive laws [30][31][32], active mechanical property modulation [33][34][35][36][37] and many other multiphysical properties [38][39][40][41][42].…”