Design and analysis of scissor-like hoop truss deployable antenna mechanism with arbitrary curvature support ribs

Abstract

To align with the development trend of large aperture, high stiffness, and high expansion ratio for space antennas, we propose a scissor-like hoop truss deployable antenna mechanism with arbitrary curvature mesh support. Compared to classical AstroMesh-hoop structures, this configuration features parabolic support ribs under the mesh surface, eliminating the need for additional high columns. It has a lower stowed height and higher in-plane stiffness, which helps maintain high surface accuracy. Firstly, the Four-Parameter Method is proposed for the dimensional design of scissor-like chains with arbitrary curvature from the perspective of the deployable antenna support structure. This method allows for controlling the deployment configuration of the scissor-like support structure by adjusting the semi-major axis length and the focal length of the initial ellipse, the angles of the unit lines, and the x-coordinates of the fitting points. Then, a three-dimensional scissor-like hoop design with joint scale that satisfies the deployable conditions is performed. Subsequently, two major issues called over-deployment and bistability are discussed, which need to be considered when applying scissor-like elements (SLEs) to space-deployable antennas. The mechanisms behind these issues are analyzed from a kinematic perspective, and optimization methods are proposed. The effectiveness of the optimization methods is verified through dynamic software simulations and a prototype. The high in-plane stiffness of the configuration is verified by finite element analysis.