Static and Dynamic Characterization of Some Tensegrity Modules

Abstract

A set of procedures was presented for characterizing static and dynamic response of tensegrity modules. The procedures were applied to two tensegrity modules: a six-bar spherical module and a two-stage cylindrical module with three bars at each stage. The singular value decomposition of the initial equilibrium matrix revealed prestress and infinitesimal mechanism modes. The prestress stiffening effect of infinitesimal mechanism modes was found to be isotropic at each node. In the initial quasi-static loading, infinitesimal mechanisms exhibited soft response. As the deformation advanced, the stiffness of tensegirty modules increased almost quadratically with infinitesimal mechanism amplitudes. Modal analyses revealed that the lowest modes were those of infinitesimal mechanism modes and their natural frequencies were an order of magnitude smaller than those of higher deformation modes.