A reconfigurable deployable spatial 8R-like mechanism consisting of four angulated elements connected by R joints

In this paper, a novel reconfigurable deployable spatial 8R-like mechanism consisting of four angulated elements connected by revolute (R) joints is presented and analyzed. Based on the layer arrangement and size adjustment of links, the reconfigurable angulated element with four quarter-platforms is designed. Then the reconfigurable deployable spatial 8R-like mechanism is constructed for the first time by connecting four reconfigurable angulated elements with four pairs of coaxial R joints. The obtained mechanism has two basic plane-symmetric modes and five evolved modes, and it can switch between a total of seven modes via different transition configurations. Further, the mobility and kinematics of the mechanism in two basic plane-symmetric modes are analyzed, configurations of the mechanism in five evolved modes are given, and the switch scheme of the mechanism between its seven modes is illustrated. Finally, a prototype is fabricated and tested to verify the feasibility of the proposed spatial 8R-like mechanism.