Structural Synthesis and Classification of the 3DOF Translational Parallel Robot Mechanisms Based on the Units of Single-Opened-Chain

Based on the units of single-opened-chain limb, some structural laws of deficiency-rank parallel robot mechanisms are revealed, and a systematic and effective new method for structural synthesis of 3d.o.f. translational parallel robot mechanisms is put forward in this paper. 31 mechanisms are synthesized and classified, 27 of which are presented for the first time. The method proposed in this paper is of universal significance and has been used for the structural synthesis of deficiency-rank parallel robot mechanisms with other kinematics output types.