28 research outputs found
Soft topological modes protected by symmetry in rigid mechanical metamaterials
Topological mechanics can realize soft modes in mechanical metamaterials in
which the number of degrees of freedom for particle motion is finely balanced
by the constraints provided by interparticle interactions. However, solid
objects are generally hyperstatic (or overconstrained). Here, we show how
symmetries may be applied to generate topological soft modes even in
overconstrained, rigid systems. To do so, we consider non-Hermitian topology
based on non-square matrices, and design a hyperstatic material in which
low-energy modes protected by topology and symmetry appear at interfaces. Our
approach presents a novel way of generating softness in robust scale-free
architectures suitable for miniaturization to the nanoscale.Comment: updated articl