Experimental investigation of the softening-stiffening response of tensegrity prisms under compressive loading

TL;DR

This paper introduces new assembly methods for bi-material tensegrity prisms and experimentally investigates their compressive behavior, revealing a transition from stiffening to softening depending on geometric and prestress conditions.

Contribution

It presents easy-to-implement assembly techniques and provides experimental evidence of the softening-stiffening response transition in tensegrity prisms.

Findings

Compressive response switches from stiffening to softening at large displacements.

Assembly methods include string-first and base-first approaches.

Behavior depends on geometric and prestress variables.

Abstract

The present paper is concerned with the formulation of new assembly methods of bi-material tensegrity prisms, and the experimental characterization of the compressive response of such structures. The presented assembly techniques are easy to implement, including a string-first approach in the case of ordinary tensegrity prisms, and a base-first approach in the case of systems equipped with rigid bases. The experimental section shows that the compressive response of tensegrity prisms switches from stiffening to softening under large displacements, in dependence on the current values of suitable geometric and prestress variables. Future research lines regarding the mechanical modeling of tensegrity prisms and their use as building blocks of nonlinear periodic lattices and acoustic metamaterials are discussed.