Analysis and design method of a class of reconfigurable parallel mechanisms by using reconfigurable platform

This paper proposes a method to design reconfigurable parallel mechanisms by applying reconfigurable platforms. According to the requirements of convenience and reliability, the basic rules for designing a reconfigurable platform are proposed. Based on a planar four-bar mechanism, single- and double-stage mechanisms are designed based on DOF (Degree of Freedom) formulation, and the single- and multi-loop reconfigurable platforms are both presented. For the spatial reconfigurable platform, the F1 (one independent force), C1 (one independent couple), F2C1 (two independent forces and one independent couple), and F1C2 (one independent force and two independent couples) over-constrained mechanisms are designed according to screw theory. To meet the multi-limb, parallel-mechanism structural requirement, single-loop over-constrained mechanisms are developed to multi-loop over-constrained mechanisms. Finally, a typical reconfigurable parallel mechanism is selected. Both the kinematics and performance analysis are investigated, and dimension synthesis based on multi-objective optimization is explored using some global indices.