Abstract: For the modular configuration of the deployable truss antenna reflector, the degree of freedom (DOF) of the module and multi-module were analyzed based on the screw theory,and the module combination idea was adopted to reduce the design complexity of deployable antenna reflector. Firstly, the module with a planar working surface was composed of three 3RR-3RRR tetrahedral elements, then the truss antenna reflector was formed by the modules. Secondly, in view of the expected deployable motion of the antenna , the expansibility of the modular truss antenna was verified by the screw theory. Finally, the connecting motion pairs between two modules were designed and optimized to achieve the maximum storage ratio. The research shows that the modular deployable antenna reflector has good expansibility. When the adjacent parts of every two modules are connected with universal joints, the upper or lower disks can be on the same plane, and the antenna reflector can be completely folded with 8 DOFs.After modules networking, the truss antenna reflector has the advantages of high storage ratio and less DOFs, which can be deployed by the motor drivers to realize the controllable deployment, and has good application in the field of aerospace institutions.

Key words: reflector, modular configuration, screw theory, motion pairs, storage ratio