Static performances of scissor structures

Abstract

Scissor structures have very promising applications and have attracted much attention due to their novel characteristics of being deployable and foldable. However, most of the current studies have focused on its geometric and kinematic characteristics, while neglecting the analysis of their mechanical properties as load-bearing structures. In this study, general formulas for calculating the internal forces and equivalent bending stiffness of scissor structures are derived and verified using finite element method. The results show that the analytical and numerical simulation solutions are in good agreement and the expansion angle is the main factor affecting the static performances of the scissor structures. In particular, the extreme increase in axial force at expansion angles above 60°will lead to instability problems. Therefore, special attention should be paid when determining the expansion angle at or above 60°. Herein, the bending moment dominates the internal forces and the stresses generated by the bending moment exceed the axial forces by a factor of about 10–30. This study is expected to contribute greatly to scissor structure design by quantitatively evaluating preliminary design, exploring the impact of various parameters, optimizing design, and understanding limitations and potential issues.