Synthesis Method of Combined Weakly-coupled Parallel Mechanisms

doi:10.3901/JME.2025.17.041

Abstract

Abstract: In order to comprehensively obtain 3T3R parallel mechanisms with weakly-coupled characteristics, a novel synthesis method of weak coupling mergers is proposed. First of all, according to the weak coupled characteristics of the machanism, the structural power matrix, and derive the weak coupled conditions of the spatial freedom driving force on the graphic exercise without work; Secondly, according the relationship between the branches dynamic screw and the driver screw, the relationship between the branches dynamic screw and non-driving screw, the motion composition of each branch chain is obtained, the plane and the space sub -parallel mechanisms are synthesis separately; Further, optimize each branch chain of the synthesis sub-mechanisms, and add motions which does not affect the output movement, that each branch chain can meet the requirements of the final expectations; Finally, the plane mechanism and the space mechanism are combined, and a reasonable branch layout is carried out to complete the combination of six free coupling and coupling combined organization type, obtain several new types of six degrees of freedom (6-DOF) parallel mechanisms. The synthesis method proposed in this paper can be applied to other degrees of freedom for weakly coupled parallel mechanisms type synthesis, and enriches the synthesis theory of parallel mechanisms.

Key words: weekly-coupled parallel mechanisms, type synthesis, synthesis method, screw theory, novel 6-DOF parallel mechanisms

CLC Number:

TH112

LI Shihua, XU Hongyu, WANG Sen, GAO Xueyuan, HAN Xueyan. Synthesis Method of Combined Weakly-coupled Parallel Mechanisms[J]. Journal of Mechanical Engineering, 2025, 61(17): 41-49.

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