Structural comparison of scissor-hinge linkages

Deployable structures can deploy from a compact to an expanded configuration by changing their sizes. The behaviors of these structures depend on some parameters such as geometric shape, member sizes and kinematic properties. To provide the deployment, not only the arrangements of structural members but also some restrictions must be considered. Moreover, contiguous members of the structures must let the large rotations to provide the transformation between different geometric forms from fully folded to fully deployed configurations. These requirements have an important impact on the fundamental properties of the structures related with structural performance, such as stiffness and strength. In this paper, stiffness of different scissor-hinge linkages are analyzed and compared. These linkages cover the same span with almost the same geometry and have the unit elements with same size and same weight. However, the geometry of unit elements is different from each other. The paper investigates the effect of this difference on the stiffness of whole system