Dial-in Topological Metamaterials Based on Bistable Stewart Platform

  title={Dial-in Topological Metamaterials Based on Bistable Stewart Platform},
  author={Ying Wu and Rajesh Chaunsali and Hiromi Yasuda and Kaiping Yu and Jinkyu Yang},
  journal={Scientific Reports},
Recently, there have been significant efforts to guide mechanical energy in structures by relying on a novel topological framework popularized by the discovery of topological insulators. Here, we propose a topological metamaterial system based on the design of the Stewart Platform, which can not only guide mechanical waves robustly in a desired path, but also can be tuned in situ to change this wave path at will. Without resorting to any active materials, the current system harnesses… 

Figures and Topics from this paper

Topologically switchable behavior induced by an elastic instability in a phononic waveguide
While topological insulators have been widely studied, they typically appear in configurations and properties that are set once a structure is fabricated. As such, there is significant interest in
Reconfigurable elastic quantum valley Hall edge states in a piezoelectric topological metamaterial
  • P. Dorin, Kon-Well Wang
  • Engineering, Physics
    Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring
  • 2020
Unlike conventional elastic waveguides, topologically protected wave transmission in topological metamaterials is immune to backscattering and localization from lattice imperfections and sharp
Tunable in-plane topologically protected edge waves in continuum Kagome lattices
In this paper, we report the evidence of topologically protected edge waves (TPEWs) in continuum Kagome lattice. According to the bulk edge correspondence principle, such edge states are inherently
Experimental demonstration of topological waveguiding in elastic plates with local resonators
It is recent that the emergence of topological insulators in condensed matter physics has inspired analogous wave phenomena in mechanical systems, mostly in the setting of discrete lattice models.
Actively controllable topological phase transition in phononic beam systems
Abstract Topological insulators, which allow edge or interface waves but forbid bulk waves, have revolutionized our scientific cognition of acoustic/elastic systems. Due to their nontrivial
Valley-dependent topologically protected elastic waves using continuous graphene membranes on patterned substrates.
This work presents a novel structure for topologically protected propagation of mechanical waves in a continuous, elastic membrane using an analog of the quantum valley Hall effect that is robust against imperfections, is immune to backscattering losses, and supports topologically-protected wave propagation along all available paths and angles.
Recent advances in topological elastic metamaterials
This paper provides a comprehensive overview of the flourishing research frontier on topological elastic metamaterials, and highlights prominent future directions in this field including three-dimensional elastic topological phases and higher-order topological insulators.
Experimental Evidence of Robust Acoustic Valley Hall Edge States in a Nonresonant Topological Elastic Waveguide
This paper presents experimental evidence of the existence of acoustic valley Hall (AVHE) edge states in topological elastic waveguides. The fundamental lattice is assembled based on a non-resonant
Topological spin-Hall edge states of flexural wave in perforated metamaterial plates
This paper investigates the pseudo-spin based edge states for flexural waves in a honeycomb perforated phononic plate, which behaves as an elastic analogue of the quantum spin Hall effect. We utilize
Observation of topological edge states of acoustic metamaterials at subwavelength scale
Topological states are of key importance for acoustic wave systems owing to their unique transport properties. In this study, we develop a hexagonal array of hexagonal columns with Helmholtz


Topological mechanics of gyroscopic metamaterials
This work presents an experimental and theoretical study of an active metamaterial—composed of coupled gyroscopes on a lattice—that breaks time-reversal symmetry and presents a mathematical model that explains how the edge mode chirality can be switched via controlled distortions of the underlying lattice.
Subwavelength and directional control of flexural waves in plates using topological waveguides
Inspired by the quantum spin Hall effect shown by topological insulators, we propose a plate structure that can be used to demonstrate the pseudo-spin Hall effect for flexural waves. The system
Topological photonics
Topological photonics is a rapidly emerging field of research in which geometrical and topological ideas are exploited to design and control the behavior of light. Drawing inspiration from the
Topologically robust sound propagation in an angular-momentum-biased graphene-like resonator lattice
The concept of topological order in classical acoustics is introduced, realizing robust topological protection and one-way edge propagation of sound in a suitably designed resonator lattice biased with angular momentum, forming the acoustic analogue of a magnetically biased graphene layer.
Transport and localization in a topological phononic lattice with correlated disorder
Recently proposed classical analogs of topological insulators in phononic lattices have the advantage of much more accessible experimental realization as compared to conventional materials. Drawn to
Topologically protected elastic waves in phononic metamaterials
Numerically a phononic topological metamaterial is demonstrated in an elastic-wave analogue of the quantum spin Hall effect, demonstrating topological protection for phonons in both static and time-dependent regimes.
Topological Creation of Acoustic Pseudospin Multipoles in a Flow-Free Symmetry-Broken Metamaterial Lattice.
It is demonstrated that tuning the strength of intermolecular coupling by simply contracting or expanding the metamolecule can induce the band inversion effect between the pseudospin dipole and quadrupole, which leads to a topological phase transition.
Stress Wave Isolation by Purely Mechanical Topological Phononic Crystals
By using numerical simulations, it is shown that this asymmetry has a direct correspondence to the topological invariant, i.e., Chern number, of the system and can be utilized for directional isolation of the stress wave propagating along the phononic crystal.
Observation of phononic helical edge states in a mechanical topological insulator
The collective behavior of mechanical oscillators exhibiting the phenomenology of the quantum spin Hall effect is characterized, and the phononic edge modes are shown to be helical, and this may enable the design of topological acoustic metamaterials that can capitalize on the stability of the surface phonons as reliable wave guides.
Tunable topological phononic crystals
Topological insulators, first observed in electronic systems, have inspired many analogues in photonic and phononic crystals in which remarkable one-way propagation edge states are supported by