Research On Change Fitness Evaluation And Propagation Path Optimization Method For Complex Product

Improve manufacturing capacity is an important link in China’s development strategy,in which the level of complex product design is particularly important.In the production cycle of product,changes have become an unavoidable problem in the development of complex products due to factors such as product upgrades,supply chain congestion,and diversification of customer demand for products.Inappropriate design change schemes can lead to prolonged production times and sharply increased production costs,leading to a decline in the market competitiveness of products.Currently,there are still many shortcomings in the research on design change issues,such as unreasonable modeling of complex products,inaccurate impact assessment of design changes,and difficulty in obtaining the optimal propagation path of changes.In view of this,this thesis is dedicated to the research of change fitness evaluation and propagation path optimization methods for complex products.On the basis of constructing a complex product-supplier two-level network,a breadth first search based fitness evaluation mechanism for complex products is proposed,and a change propagation path optimization model is constructed by combining indicators such as change duration and change cost.An improved ant colony algorithm driven by problem characteristics is designed to efficiently solve the optimization model,The main work of this thesis is as follows.(1)The complex product-supplier two-layer network model is constructed,and a breadth-first search-based evaluation method for complex product adaptation is proposed.Firstly,the interrelated constraints,such as design and physical constraints between components,the supply capacity of components,and the mutual restraint relationships among suppliers are analyzed to construct a complex product-supplier two-layer network model.Secondly,an improved breadth-first search algorithm is proposed based on the propagation characteristics of design changes in the constructed two-layer network to determine the scope of propagation of design change effects in the two-layer network.Lastly,an adaptation evaluation method for complex product introduction of design changes is proposed by considering factors such as relationships among nodes,change intensity,and design tolerance.The feasibility of the proposed method is verified using the design change problem of a certain model of Skyworth television as an example.(2)An improved ant colony optimization algorithm driven by problem characteristics(IACO)is proposed to generate the optimal change propagation path.Firstly,based on the proposed method for evaluating the adaptation of complex products,a multi-objective optimization model for the optimization problem of complex product change propagation path is established by considering indicators such as the impact of changes on product performance,product change work period,and change cost.Secondly,the traditional ant colony algorithm is analyzed on its shortcomings in handling the optimization problem of product change propagation path.A new heuristic function based on change intensity,a new indicator value calculation strategy based on dynamic network structures and a self-adaptive volatility coefficient is designed as new operators or strategies.Thus,a problem-oriented IACO algorithm is proposed to search for the optimal propagation path for product changes accurately.Finally,the effectiveness of the proposed algorithm is verified using the design change problem of a certain model of Skyworth television as an example.The thesis has 23 figures,6 tables,and 91 references.