| With the improvement of the people’s living standard and development of economic globalization and product diversification, the customers’demands show a diversified and personalized features, the customers’demands in low-cost, high quality and personalization aspects have become the serious challenges jointly faced in current manufacturing industry, modular design and manufacture are the important approaches to meet these challenges. The modular design is used to quickly combine into the individuation products which can satisfy the demand of the customers by the reasonable product modularization system and also reduce cost due to the batch production and management of the universal modules so as to effectively resolve the contradiction between low cost and high quality of the products and satisfaction of the individuation demands. This paper conducts the research on key technologies of the modular design such as modular division method of complex mechantronic products, the metrics method of the module parameter similarity, configuration design of the modular products etc., and carries out the application research on the modular design of the wheel loaders of certain enterprise by combining the practice. The specific research contents include:(1) A min-max partition modularity method suiting complex product is proposed in this paper. Firstly, present the definition of min-max partition, then execute the primarily partition of complex products according to various complex relationships between parts and components to obtain its min and max partitions, thirdly, with these min and max partitions classify the parts and components of the complex products into different groups, then in these groups carry out the fuzzy clustering analysis using the min partition subsets as calculating unit, finally obtain the results-critical value according to the modularity polymerization degree. This method has the advantage of minimum calculation, optimum critical value and reasonable weighting coefficient. At the end, this method is applied to a wheel loaders to demonstrate its rationality and effectiveness.(2) A new modular division method based on Bill of Material (BOW) and degree of modularization (DM) is proposed in this paper. Product structure tree (PST) consisted of nodes (part or parts) is formed based on the BOM of complex products, correlation matrix (CM) and correlation graph (CG) is calculated through an analysis of relativity of geometric structure, functional and physics, the degree of modularization (DM) is defined and calculated based on CM and CG. With the optimization of DM (include the minimum and average of DM), the modular is divided in the range of PST. As an example, the methods were applied to the working unit of loaders, and the method was verified.(3) The pretreatment requirement of the module division of the wheel loaders and its unique principle of the module division are researched, the module division is performed for the wheel loaders by using the relevant module division method in this paper from multiple levels, the product is divided into17one-level modules and77two-level modules.(4) The structure similarity and parameter similarity of the electromechanical product module are researched, the metrics method of the similarities of the module structure and parameter and the module uniqueness discrimination method based on the structure similarity are proposed. The coding method and network modeling method of the module assembly type are proposed, the weighted network model is established by taking typical module for an example. The comparative intersection method is focused on research, the similarity metrics and matching method of the assembly relationship are given. Based on the similarity and matching of the assembly relationship, the method to strengthen the network matching and similarity measure is proposed and used to discriminate the module uniqueness.(5) The metrics method of the module parameter similarity and module reuse degree optimization method are researched. An optimization method of module reuse degree of module-base is proposed based on the calculation of the similarity. Firstly, the definitions of module-base, module reuse degree, similarity of module-case, similarity matrix and cluster center are introduced, and the similarity matrix are obtained by the calculation of the similarity. Then, the redundant case of module was eliminated through cluster analysis of module-base to improve the reuse degree of the module. Lastly, this method is applied to the module-base of bucket of wheel loader to demonstrate its rationality and effectiveness. With the demand of cluster analysis,12kinds of redundant case can be eliminated from the module-base while the initial number of cases is39, and the reuse degree was raised to44.4%.(6) Multi-level configuration method of the modular products is demonstrated according to the characteristics of the modular products. First, the customers’demands are divided into two types namely binding demand and selective demand, then configuration design of the modular products is presented from the multiple levels such as core platform and customized module etc. based on the analysis of the customers’demands. This paper focuses on research on the design and configuration method of core platform of the modular products, customized module and configuration method. The application research is conducted on the modular design taking the wheel loaders as the application objects.(7) The modular system design approach of the complex mechantronic products has been researched, the stages such as modular preparation of the modular design of the complex mechantronic products, modular planning, modular process and module configuration design etc. are analyzed. The four types innovation method of the products based on modularization is demonstrated.(8) The design methods of the module and module library of the electromechanical products are researched, the module design of the electromechanical products is proposed from two aspects namely module structure and module interface, construction of the module library of the electromechanical products is proposed, including module library modeling and module library database modeling, the design process and design method of the module and module library are researched. Taking the product module of the wheel loaders for an example, the module structure design, module variant design method and module interface design are analyzed.(9) The modular design platform of the electromechanical products for the wheel loaders is developed, the application verification is performed on the related research findings, engineering background analysis of the modular design of the wheel loaders, overall design of the modular design platform of the electromechanical products and the relevant design of the composition system are completed. The platform has the functions of coding management, module management and demand management etc. for the products and its components and modules, at the same time, based on multi-level configuration method of the wheel loaders, the rapid configuration design method of the wheel loaders is realized.Key technologies such as module division, the metrics method of the module parameter similarity and its application, modular product configuration etc. are solved in the modular design of complex mechantronic products by research of this paper, main results are:modular division method suited to the complex mechantronic products is presented, the characteristics such as small calculation amount, more objective and reasonable module division results etc. are possessed; the module similarity and metrics method are proposed and applied to discriminate the module repeatability and module reuse optimization; the definition of the core platform of the modular products and multi-level configuration method of the modular products are presented to effectively improve the configuration efficiency of the products. The research results have been successfully applied to the modular design of the wheel loaders. |
