For Virtual Assembly Process Planning Key Technology Research

With the increasing competition of gloabal manufacturing markets, developing and manufacturing the high-quality and low-cost products at the shortest time have been becoming the goal of each enterprise's pursuit. Carrying through assembly process planning and reasoning assembly sequence with computer can provide foundation for guaranteeing assembly feasibility and optimization during actual product assembly procedure, and is very important improving product quality, decreasing product cost and shortening production cycle.On the base of studying assembly process planning technics, in this paper, three-layer assembly information modeling is established and an assembly sequence's reasoning method depending on the layer-built modle is put forward. A solution of assembly sequence planning for a complex product can be simplified by this method, which changes a complex assembly with many of parts and components to sereval simple subassembly with few of parts and components, furthermore, to reason subassembly sequence in each layers uses generating algorithm based on disassembly with better practicality. This paper also proposes evaluating model based on fuzzy theory, which is used for evaluating and optimizing the possible assembly process.Under this premise, prototype system of process planning facing virtual assembly is tapped, and the demands of function, performance, information of the system are analyzed in detail. This paper also researches systematically key techniques such as collecting information, assembly sequence generation, etc., solves reasonably the questions of building assembly model, generating assembly sequence, evaluating and optimizing them, and provides the basis of realizing following product's virtual assembly process simulation.Prototype system verified by the reducer, indicates the feasibility and validity of assembly information building, assembly sequence planning and evaluation.