On the mechanical modeling of the extreme softening/stiffening response of axially loaded tensegrity prisms

TL;DR

This paper investigates the nonlinear axial behavior of tensegrity prisms, revealing both extreme stiffening and softening responses that depend on structural parameters, with implications for acoustic and phononic applications.

Contribution

It introduces new models predicting extreme softening behavior in tensegrity structures, expanding understanding of their nonlinear mechanical responses.

Findings

Identified conditions for extreme softening and stiffening in tensegrity prisms.

Discovered a softening response leading to snap buckling and axial collapse.

Linked mechanical behaviors to potential applications in phononic crystals.

Abstract

We study the geometrically nonlinear behavior of uniformly compressed tensegrity prisms, through fully elastic and rigid--elastic models. The presented models predict a variety of mechanical behaviors in the regime of large displacements, including an extreme stiffening-type response, already known in the literature, and a newly discovered, extreme softening behavior. The latter may lead to a snap buckling event producing an axial collapse of the structure. The switching from one mechanical regime to another depends on the aspect ratio of the structure, the magnitude of the applied prestress, and the material properties of the constituent elements. We discuss potential acoustic applications of such behaviors, which are related to the design and manufacture of tensegrity lattices and innovative phononic crystals.