Research On Sustainable Design And Assessment Methodology For Mechatronics Products

With increasing manufacturing development, there is an unbalanced development for economy, society, and environment. Sustainable design, a design concept considering environmental, social and economic feasibility, is the response to this problem. Existing design methods including environmental design, selection of green material, green process design, green packing and design for disassembly, have been studied and some results have been applied to product development. However, the environmental protection design may cause higher product cost, reduce competition in the market, and hence limit the effective implementation of sustainable design. It has important theoretical significance and practical value that the establishment of quantitative model between sustainablility and the product structure design, use intelligent methods to improve structure design, and research on the comprehensive evaluation based on multiple attribute to realize the goal of zero pollution, low cost and social benefit. It is necessary to map the social, economic and environmental requirements into the product function and structure design. Sustainability-oriented assessment criteria has the characteristics of fuzzy, qualitative and quantitative, static and dynamic, thus need quantitative assessment model using mathematical approaches from integrative and holistic viewpoint. In this research, the quantitative description method between structure design and sustainable requirements for mechatronics products is proposed, and the static and dynamic evaluation method is studied in order to meet the product sustainability requirements. Sustainable design framework is proposed based on the function structure in order to solve the broad problem of sustainable design concept leading to lack of guidance for actual product design. The relationship model of product structure and sustainable design is established based on factors of life cycle stages related to sustainability. The integrated assessment model is established to provide a comprehensive sustainability assessment framework. Furthermore, the multi-level hierarchical structure is utilized in order to feedback design improvements. As to the lack of quantitative analysis method for mapping product structure design and sustainability requirements, the sustainable design method is proposed based on product modularity. On the basis of traditional function and structure, this article integrates 6R concept(Reuse, Recycle, Reduce Recover, Redesign, Remanufacture) into module clustering criteria such as material, manufacturability, life and end-of-life options to achieve objective of sustainable design. Additionally, the relationship matrix between components is established utilizing Design Structure Matrix(DSM) which has great advantages on representing similarity and dependency relationship of component-to-component in order to determine module structure. Kernel-based fuzzy c-means algorithm is used to integrate components of product into different modules based on their correlation distance. Meanwhile, genetic algorithm is employed to determine the optimal clustering number on account of its efficiency in coming up with the global solutions. Finally, a rotor laboratory bench is utilized as a case study to illustrate the effectiveness of the proposed methodology. Based on the characteristics of complexity, fuzziness, uncertainty etc, a static evaluation quantitative model for sustainable design is established using the extension theory with the advantage of the quantitative and qualitative analysis. Furthermore, sustainability performance is calculated based on extension theory through utilizing correlation function between evaluated matter-element and classical field matter-element. Additionally, the weights of criteria are determined using entropy weight approach with the advantage of objective evaluation by exploiting the useful information of data to a maximum extent. Product sustainability performance index of manufactured product is obtained by integrating sub-criteria into criteria level. Face milling test conducted on CNC Vertical Machining Center illustrates validity of the proposed method for assisting the engineers or designers to define sustainability performance of machining process. Illustrative example involving manual mill and CNC machine tools in three use environments is discussed to demonstrate the application of the proposed methodology. The results illustrate that machine tool with high level of automation should consider sustainability aspects when increasing functionality. The static assessment method is unfit for handing the dynamic criteria related to time, thus system dynamics-based assessment method is proposed. System dynamics method is employed to establish sustainability assessment model for simulating complex interaction between sustainability indicators and searching appropriate quantitative solutions to measure product sustainability during life cycle stage. VEBSIM software process-based causality model is established using dynamic index. Illustrative example involving HURCO and HAAS machine tools is discussed under the same time, machining parameters, which demonstrates the validity considering dynamic criteria when calculates product sustainability performance index.