Topological Solitons Make Metamaterials Crawl

Abstract

In recent years, the ability to propagate topological solitons in mechanical metamaterials has unlocked unpaved paths towards potential applications in wave propagation, mechanical logic, and shape morphing. Here we demonstrate how a multistable metamaterial can harness topological solitons with coupled rotational and translational components, and become, itself, a crawling robot. We start by characterizing the topological solitons via experimental measurements and analysis. We then use their rotational component to produce a favorable gradient of friction between the metamaterial and the underlying substrate. This, in turn, creates locomotion. Previously proposed crawling robots have usually required complex control of multiple actuators. In contrast, our robot can be powered by a single actuator and all features needed for locomotion are embedded in the mechanics, and activated by the topological solitons.

Spin-induced valley polarization in heterobilayer Janus transition-metal dichalcogenides

“…For the coupling between occupied states and unoccupied states with the same spin (↑↑, ↓↓), a positive and a negative contribution to MAE is given when the same magnetic quantum numbers | ∆m | = 0 and | ∆m | = 1, respectively; for the coupling with different spins states (↑↓, ↓↑), the contribution to MAE is completely opposite to the above case. When the magnetic quantum numbers | ∆m | = 2 indicate that hopping between occupied and unoccupied states is prohibited, there is no contribution to MAE [56]. In order to better evaluate the contribution of different orbitals to the MAE, orbitals…”

The design, manufacture and application of multistable mechanical metamaterials-a state-of-the-art review

“…These 3D printing methods include macroscopic manufacturing technology and mesoscopic/microscopic manufacturing technology. With the support of these advanced manufacturing technologies, different types of multistable mechanical metamaterials have been prepared and have shown great application prospects in soft actuator/robot [30][31][32][33], mechanical storage/logical operation [26,[34][35][36][37], energy absorption [18,21,24,38,39], and wave control [40,41].…”

Advanced Fabrication of Mechanical Metamaterials Based on Micro/Nanoscale Technology

“…The ability to obtain programmable behavior through the interplay between material and structure leads mechanical metamaterials to the venue beyond the mechanical field, where studies have been reported on their active, adaptive, and actuating characteristics. Recent research trends have shed light on creating autonomous systems by intelligent matter in mechanical metamaterials for sensing, [20][21][22][23] energy harvesting, [24][25][26][27][28] actuation, [29][30][31][32] adaptation, [33][34][35][36] computation, [37][38][39][40][41] information processing, [42][43][44] etc. (see Figure 1a.…”