Sustainable Product Platform Design For Urban Rail Vehicle

Urban Rail Vehicles(URV)are the backbone of urban public transport.They are technology-intensive mechatronic products that integrate high-tech such as machinery,electronic,control,and communication,and show the characteristics of energy-saving,large transportation capacity,low pollution and safety.Chinese URV has developed rapidly under the pull of national policy and market demand since the beginning of the 21 st century.Manufacturers of URV have ushered in good development trends,but also faced severe challenges.On the one hand,the reuse rate of parts is low,and there are many valueless differences in products,which makes it difficult to obtain scale economies.On the other hand,the market adaptability is poor,and the products are inadequate to respond to dynamic customer needs,making it difficult to obtain the range economies.To tackle the above problems,the academic and industry have adopted product platform strategies to meet the diverse customized requirements as much as possible without sacrificing the scale economies of enterprises.However,the design process of the URV product platform is mostly One-off mode and the design results are mostly static.It does not take into account the dynamic changes of external and internal factors on the product platform design,resulting in insufficient adaptability and unable to maintain the robust ability and adaptability of product platform.To solve this problem,this paper proposes a sustainable product platform design method and develop a management tool to support the continuous positioning,planning,construction,application and update of the product platform.The proposed methodologies and systems are verified and applied in an actual project.The main research contents of this paper include six parts,as follows:(1)The definition and framework design of sustainable product platform.The sustainable product platform of URV is proposed based on the existing product platform design theories.Specifically,the connotation of the sustainable product platform is defined,and the composition,application and update model of the sustainable product platform is analyzed.Furthermore,the framework model of the sustainable product platform including data,theory,technology,tool,component,and system is proposed.Finally,the process model including product platform positioning,platform planning,product platform construction,and product platform update is proposed.(2)Product platform positioning.The factor analysis method is used to divide the URV market,and the life cycle of each market is identified based on the Logistic curve.Then,the weight of market segment is obtained by the life cycle and share of each market.Furthermore,facing the weight and life cycle of market and considering the investment timing of project,real option is used to build an investment positioning model of product platform project.Finally,the positioning model is figured out based on dynamic programming and Monte Carlo simulation methods,which helps companies to continuously use right strategies to develop product platform project in the right market segment at right time.(3)Product platform planning.Based on the results of product platform positioning,the external data including transactions and requirements and the internal data including BOM and module instances in the target market are collected and processed.Then,the two classification indicators of module similarity index and module change index are calculated based on the external and internal data.Finally,an updateable module classifier is built by using CART algorithm based on the module classification indicators,to achieve the continuous planning of common and differentiated modules.(4)Product platform construction.Based on the planning results of common and differentiated modules,the relationship between modules is analyzed and a module interface information model is built.Then,the instances of common modules are continuously developed based on multi-attribute decision making methods.Furthermore,the configuration instances and variant templates of adaptable modules are continuously developed by busing K-means clustering algorithms,multi-attribute decision making,grey correlation analysis,and association design technology.(5)Product platform update.For the established product platform,the status indicators of product platform are analyzed and identified,including the product platform life cycle,product platform economic indicators,and product platform technical indicators.Then,the operational status of the product platform in each life cycle,including two states of normal operation and abnormal operation,are identified based on the product platform economic and technical indicators.For the product platforms that show the abnormal operation,considering market and technology uncertainties,the risk decision method is used to achieve the continuously update of the product platform modules.(6)Product platform system development.Based on the theoretical and technical research results of the sustainable product platform design,a system software is developed to continuously support product platform planning,construction,application,and update.Firstly,the business requirements of the system are obtained through the exchanges with enterprises' engineers.Then,the overall architecture and main functional modules of the system are designed.Furthermore,the system interface is developed by using the C/S and B/S architecture.Finally,the system is verified by taking the design of the A-type subway product platform.This paper shows that the research of the sustainable product platform is a supplement and improvement to the existing R&D technology system of URV.The sustainable product platform not only enhances the adaptability of enterprises to respond to market requirements,but also improves the reuse rate of parts,which improves the product competitiveness.In short,the sustainable product platform is worth constructing to improve the level of digital design and management of enterprise...