Research On The Methods Of Mechanism Evolutionary Design Based On Unit Coupling

A new theory and method of evolutionary design for mechanism motion scheme based on unit coupling is presented in this dissertation. The new theory and method is based on the study of effective way to transfer and exchange design information between different stage in mechanism design, including definition and classification of Kinematic Chain Unit (KCU), abstracting the commonly Unit Couple Semantics(UCS), foundation of coupling constraints, managing the design information lie in mechanism design and linkage-evolutionary of mechanism motion scheme. The theoretical research is proved with the development of the mechanism motion scheme design prototype system.The dissertation is organized as follows:Chapter 1 gives an overview of the current situation, character and key technologies of Computer Aided Product Motion Scheme Design. Then, the merits and deficiencies of existing design method for product motion scheme design are discussed. After that, the main strategy of the new theory for mechanism evolutionary design based on unit coupling is introduced.Chapter 2 presents the basic principle and method of mechanism motion scheme design based on unit coupling. Through analyzing the unit-character lie in mechanism design, the design units with formal definition are abstracted, and classified to several groups according to their character. Then, the dissertation gives the evolutionary process of mechanism motion scheme guided by the evolution of design units.Chapter 3 introduces the key factors in the process of unit coupling through examining the coupling constraints, and investigates the whole process of unit coupling, including the matching of unit relations, coupling the constraints of design units, driving the coupling semantics and so on. In the last, a management model of information of mechanism motion scheme design is founded.Chapter 4 puts forward the evolutionary process of mechanism motion scheme which based on the enrichment of the coupling constraints. The library of KCU instance is constructed to support the mapping from KCU to KCU instance. Through enriching and detailing the constraint sets of kinematic chain, the evolution of UCS is realized. Guided by the data structure of relations between design units, the dissertation gives the whole process of evolution of mechanism.With the theory and methods in this dissertation, chapter 5 introduces the mechanism motion scheme design prototype system, coming up with some examples.Finally, conclusions were drawn from this dissertation with recommendation for future research in chapter 6.