Initial shape finding and modal analyses of cyclic right-cylindrical tensegrity modules

Initial equilibrium and modal analyses of cyclic right-cylindrical tensegrity modules with an arbitrary number of stages are presented. There are m (⩾3) bars at each stage. The Maxwell number of the modules is 6−2m and is independent of the number of stages in the axial direction. Calladine’s relation reveals that there are 2m−5 infinitesimal mechanism modes. For multi-stage modules the necessary conditions for axial assembly of one-stage interior modules with the same internal element forces are investigated. One-stage modules with either congruent right-cylindrical modules or geometrically similar cone-shaped modules satisfy the necessary conditions. In this paper, the axial assembly of right-cylindrical modules with flip or quasi-flip symmetry is considered. For pre-stressed configurations, modal analyses are conducted to investigate the mode shapes of infinitesimal mechanism modes.