Numerical Modeling of Force-Stiffness Response of Cross-Linked Actin Networks Using Tensegrity Systems

Xian Xu,Yaozhi Luo,Yafeng Wang

doi:10.1155/2015/182918

Abstract

A three-dimensional tensegrity structure is used as a computational model for cross-linked actin networks. The postbuckling behavior of the members under compression is considered and the constitutive relation of the postbuckling members is modeled as a second-order polynomial. A numerical scheme incorporating the equivalent constitution of the postbuckling members is used to predict the structural response of the tensegrity model under compression loads. The numerical simulation shows that the stiffness of the tensegrity structure nonlinearly increases before member buckling and abruptly decreases to a lower level as soon as members buckle. This result qualitatively mimics the experimentally observed stiffness to compression stress response of cross-linked actin networks. In order to take member length variety into account, a large number of simulations with the length of buckling members varying in the given range are also carried out. It is found that the mean response of the simulations using different buckling member length exhibits more resemblance to the experimental observation.

Highlights

Tensegrity is a special class of pin-jointed assemblies, whose stability is provided by the self-stress state between tensioned elements and compressed elements
The possible reason for this is that in the tensegrity model we considered the members in compression are identical to each other and buckle simultaneously under the given load, while in the actin networks there are numerous filaments with various lengths under compression, which buckle sequently as the load increases
This paper presents a numerical study on simulating the mechanical response of cross-linked actin networks by a 3D tensegrity model

Summary

Introduction

Tensegrity is a special class of pin-jointed assemblies, whose stability is provided by the self-stress state between tensioned elements and compressed elements. Sculptures containing the essential characteristics of tensegrity were first created by Snelson in 1948, while the term “tensegrity” was first used by Fuller in 1961 to name a class of cable-bar structures in a patent [1, 2]. Since it was invented a half century ago, tensegrity has attracted much attention from both researchers and practicers. The limited use of the system can be attributed to its inherently complex and flexible nature It inspired some innovative structural systems such as cable domes [3] and suspendeddomes [4], which have attained great success in architectural applications. A comprehensive review and discussion on the development and applications of tensegrity can be found in Motro [16], Skelton and de Oliveira [17], and Sultan [18]

Methods

Results

Conclusion