Abstract: The topological structure characteristics of a mechanism are innate topological invariants of the mechanism which reflect the essential features of structural theory, kinematics and dynamics. Through deeply analyzing the topological structure characteristics of the parallel mechanisms which are succeeded in design and application, beneficial enlightenment and lessons can be gotten. By using position and orientation characteristic (POC) method based topological structure synthesis theory, the 8 famous parallel mechanisms, which include Delta, Diamond, Tricept, TriVariant, Exechon, Z3, H4 and Stewart mechanism, and 26 parallel mechanisms which have large promoted value, are analyzed, from which, the topological structure characteristics are obtained and some common rules are concluded. Based on this, a 5-DOF hybrid testing platform and a 5-DOF hybrid spraying robot are successfully developed. The result shows that POC method based topological structure synthesis theory can well reveal key topological properties of all parallel mechanisms in industry, while these common rules for design and application of parallel mechanisms obtained provide an important reference and enlightenment for theory research, industrial design and application of parallel mechanisms.

Key words: good parallel mechanisms, parallel mechanisms, POC method, topological structure analysis, topological structure characteristics