Design and analysis of modular deployable antenna mechanism based on a class of self-limiting position units

With the rapid development of space technology, deployable mechanisms have attracted much attention because of their potential applications. In this paper, novel deployable mechanism units with self-limiting position function are proposed. Then, the ring truss deployable mechanisms are constructed according to two schemes of shared-nodes and shared-edges. The ring truss deployable mechanism constructed using the shared-edges scheme has higher stability, to further expand the application potential of this scheme, a procedural method is proposed to obtain the ring topology with larger aperture. Next the degree of freedom(DOF) of deployable units are analyzed using screw theory, and according to the synchronization between the units, it is proved that the constructed ring truss deployable mechanisms have only one DOF. The dynamic model of the deployable mechanism unit with the passive actuation is established and verified by simulation. Compared with others, the deployable mechanism units proposed in this paper have the advantages of strong scalability and high stability, and they have good application prospect in constructing large deployable mechanisms.