Comparative Analysis of Two Tensegrity Grids Considering Slack and Rupture of Cables

摘要

Tensegrities have found many technologically important applications in architecture, aerospace, biological engineering, and soft robotics. Loss of members in tensegrity structures may have an important effect on their nonlinear behaviors. In this paper, the effect of the rupture of cables on two periodic tensegrity grids (with and without clustered cables) is investigated by using the corotational approach. A tangent stiffness matrix is derived for a clustered cable running through pulleys. The rupture of cables is modeled by considering the elastoplastic deformation. The proposed finite element formulation is validated by a simple example and then applied into the analysis of complex tensegrity grids. The propagation of slack and the rupture of cables are discussed in detail. The results of the numerical simulation show that clustered cables play important roles in sharing external loads such that the clustered tensegrity grid has a uniform deformation in comparison with the classical one. On the other hand, interestingly, a global deformation resilience induced by local mechanism modes is observed for the classical tensegrity grid. The finding may be valuable for designs of tensegrity-based metamaterials and energy harvesting devices. The work provides an efficient and numerical way of nonlinear analysis of both classical and clustered tensegrities.