Evolution of Natural Frequencies in Tensegrity Systems: A Case Study

In this study, a dynamic analysis of self-stress levels of tensegrity systems is proposed. A direct relation between the first natural frequency of these systems and the levels of self-stress in the elements is established. It constitutes a first step toward the study of the adaptability of tensegrity systems to external loads; this adaptability could be realized by adjusting the levels of self-stress of one or several cable elements. The study is carried out using continuous struts tensegrity systems made of linear associations of simplex type modules. When subjected to static loading, tensegrity systems show an evolution of their frequencies with respect to the tension levels in the elements. The frequencies are computed assuming the structure oscillates linearly about its static equilibrium position. This evolution can be used, to associate the level of selfstress to a desired resonant frequency of the system. The harmonic dynamic loading of these systems, confirms their non linear characters and show a particular evolution of the tension-frequency relation.