Stiffness properties of “star” tensegrity structures under the compressive loading

Purpose This paper proposes a method for analyzing structural deformation under axial load, using “star” tensegrity structures as the research object. The approach simplifies the calculation process by solving a nonlinear force-density equation with only three variables: height, radius and twist angle. Design/methodology/approach The geometrical parameters of the loaded structure are obtained by solving the nonlinear force-density equation. Structural stiffness is analyzed under different prestress levels, complexities and connection modes. By defining the rates of change of twist angle and height, the relative structural deformations of different “star” tensegrity structures are compared under various loading conditions, including those with and without gravity. Findings The results show that prestress has a significant impact on structural stiffness, with higher prestress leading to improved stiffness. However, increased structural complexity and certain connection mode variations lead to reduced stiffness. Among the analyzed structures, the three-bar “star” structure exhibits the best stiffness with the smallest relative deformation. Deformation under gravity is generally greater than in the absence of gravity, and the influence of gravity intensifies as the number of bars increases. Compared to a tensegrity prism, the “star” structure offers greater geometric flexibility and higher deformability. Originality/value This paper provides theoretical references and insights for the design and optimization of “star” tensegrity structures in practical applications.