The Research On Assembly Sequence Planning For Airfoil

The problem of assembly sequence planning (ASP) is a kind of NP optimization problems, so it is very difficult to find an assembly sequence which can achieve the assembly request. Therefore, assembly sequence planning had been becoming the bottleneck of reducing the cost and shortening the production time of a product. The technique of virtual assembly can quickly evaluate and optimize the assembly plan by simulating the assembling procedure; it also can achieve the product design, assembly process planning, functional analysis and quality testing adopting computer simulation and 3D interactive visual model. ASP is a key technique of virtual assembly. In this thesis, a system planning of assembly sequence planning module in Virtual Assembly system is proposed which is based on analyzing the characteristic of airfoil assembly and assembly design. The core techniques of assembly sequence planning which based on genetic algorithm and fuzzy set theory are investigated in detail. Main research work and achievements are as follows:1. Researches and analyzes aircraft assembly design task, such as assembly methods, assembly action and assembly direction etc. Summarizes the characteristics and workflow of wing assembly design.2. The assembly sequence planning of product is discussed. The paper presents the method - assembly sequence planning based on genetic algorithm, which is adopted by the module.3. The genetic algorithm adopted the encode method of gene-group, expressed the assembly information of parts such as assembly actions, assembly tools, assembly fixtures and assembly directions, etc.4. The method proposed fuzzy set-based fitness function, by which can judge and optimize the assembly sequence planning.5. Based on CATIA V5 CAD Software and CAA FOR CATIA V5 Toolbox, designed and developed a module for airfoil's assembly sequence planning.