Research On Influence Analysis And Management Method Of Design Change On Complex Aerospace Product Development

Nowadays,the design and manufacturing level of complex products is the core competitiveness of manufacturing industry to occupy market.Design changes are inevitable during the development process of complex products.Take aerospace loads as an example,China’s aerospace missions have entered the stage of high-frequency launch with the rapid development of China’s aerospace technology.Aerospace product manufacturing enterprises are faced with the problem of increasing the frequency of design changes in the case of multiple projects in parallel,short development cycle and reduced cost.Frequent design changes will consume a lot of manpower and material resources,It will not only increase the development cost,but also delay the delivery time of products,and even delay the whole launch mission.If the impact analysis of design change is not perfect,it will also cause serious quality accidents.How to respond quickly and accurately during the process of design changes and find the critical path of design change to save costs and shorten the lead time are the urgent problems to be solved in manufacturing enterprise.Based on the in-depth investigation of design change management technology and in view of the shortcomings existing in the current design change management,this thesis studies the impact analysis and management methods of design change.In order to guide enterprises to plan possible product changes and reduce the risk of "avalanche" caused by design changes,this thesis studies the impact prediction of design changes based on the design structure matrix model.In order to find the critical path of design change accurately and quickly,the key technologies of design change path search and evaluation are studied.Aiming at the problems in the implementation of design change,the management method of design change is studied.The main research contents of the dissertation are as follows:(1)The modeling method of complex products is studied.Firstly,according to different application objects in complex product design change management,the multidisciplinary DSM model,structure based DSM model and parameter based DSM model are established respectively.Secondly,the analysis method of the model is studied,which provides a model basis for the prediction and analysis of the impact of design change.(2)The prediction method of design change impact is studied.Firstly,the global DSM model of complex products is established by using the hierarchical method,and the influence range of design change is preliminarily predicted by using the combination of traversal method and division method.Then,according to the communication mode of design change,the direct risk and comprehensive risk matrix of design change are established,and the influence of design change of complex products is quantitatively predicted,which provides the theoretical basis and data support for early planning for the managers of design change.(3)The propagation path search and evaluation method of complex product characteristic parameter change is studied.The characteristic parameter complex network model is established.According to the different positions of characteristic parameters in the complex network and the path search mechanism,the hierarchical characteristic parameter change propagation path search method is formulated,and the critical path evaluation index and optimization strategy are established,which provides an efficient and reasonable decision-making method for the selection of design change path.(4)Aiming at the problems of long cycle,inconsistent product change data and imperfect verification in design change management,the task management of complex product design change is studied.Firstly,the management process of design change is analyzed,and the design change activities are allocated through iterative process modeling.According to the analysis of the evolution rate and sensitivity of upstream and downstream activities,the decision-making method of shortening the task cycle is proposed,the evaluation index of activity execution is formulated by using the concept of information engine,and the technical state management process and technical state verification process are established to minimize the negative impact of design change.(5)The research content of this paper is applied to engineering practice.Taking the design change of a space load on the daily calibration mechanism as a case,the impact of the design change is predicted,and the key path is determined through the search and evaluation of the propagation path of the design change.The effectiveness of the design change management cycle is verified by using the technology change management cycle,and the effectiveness of the design change management cycle is proved.Through the research of this dissertation,a series of methods of impact analysis and task management of complex product design change are proposed,which provides effective decision-making methods and theoretical guidance for designers and managers in complex product design change process management.