The novel synthesis method of decoupled generalized parallel mechanisms based on motion transmission

Compared with traditional parallel mechanisms, decoupled parallel mechanisms exhibit superior motion control capabilities. In this paper, a novel synthesis method for decoupled generalized parallel mechanisms (DGPMs) based on motion transmission is proposed. This method enables the successful construction of passive chains capable of achieving input-output motions with identical rotational/translational directions and proportional velocities in both planar and spatial configurations. Subsequently, DGPMs with diverse motion types are realized by modifying the drive chain while maintaining invariant passive chains. The proposed methodology modularizes the synthesis process, allowing new mechanism designs to be generated simply by altering the input motion type of the drive chain. Furthermore, coupling chains in each branch are optimized through the integration of multiple DGPMs, where their moving platforms are rigidly interconnected to form a more stable multi-branch DGPM architecture. A representative 6-degree-of-freedom (DOF) mechanism is selected for comprehensive performance analysis. Finally, potential applications in assembly and welding manipulators are discussed to illustrate the practical relevance of this mechanism class.