Abstract: It is an important issue of the mechanical product assembly technology research for conceptual design based on the representation of the assembly model. It is not able to be solved well through the forthcoming CAD system based on the geometrically constrained relation. A new representation method of product assembly model for conceptual design based on the trinity of assembly semantics is put forward, and the assembly semantics relation graph is proposed to express assembly semantic relations among parts. To build many layers of semantics relation and the assembly driving based on semantics which can support the conceptual assembly model through the assembly semantics relation graph. Then both the top-down design process commencing with conceptual design and the bottom-up design process commencing with detail design of mechanical product are implemented.

Key words: Assembly driving, Assembly model, Conceptual design, Semantic relating, Trinity