Abstract: Modular deployable antenna has the characteristics of good versatility, strong adaptability and expansion flexibility, and is a configuration form with great development potential to meet the needs of in-orbit assembly and construction of large-scale antenna in the future. In order to better grasp the mechanical characteristics of the antenna structure, the rigid-flexible coupling design and driving force analysis of the antenna structure are developed. Firstly, a scheme design of modular deployable antenna structure is carried out, and the structure composition and deployment/stowed principles are described. Secondly, based on the analytical geometric method, a mathematical model of the equivalent envelope circles is developed, and key parameters such as the angle of the rib unit are obtained, then the three-dimensional model of deployable antenna structure is established. Thirdly, the flexible processing of radial long beams such as upper beam, diagonal beam and lower beam is carried out, and a multi-body dynamic model of rigid-flexible coupling of modular deployable antenna mechanism is established by multi-body dynamics simulation software. Finally, the change laws of the deployable driving force of single module and multi module antennas at different confinement positions are analyzed from the aspects of gravity and no gravity. The results show that if there is gravity in the deploying process, the choice of constraint position has a great influence on the driving force. In the absence of gravity, the antenna constraint position has little effect on deployment. The structural design and multi scheme driving force analysis can provide some reference for the prototype development and engineering application of this antenna.

Key words: deployable antenna, modular structure, rigid-flexible coupling structure, space geometry modeling, driving force analysis