Study On Product Configuration In Manufacture

Content:Mass Customization (MC) is a production mode, which provides the products and services satisfying the customer's personal demands, having the low cost, high quality and high efficiency as the same as those provided by Mass Production. Along with the globalization of manufacture competition and diversification of customer demand, MC production mode is adopted by more and more enterprises, and holds the leading status gradually.Product Configuration (PC) is a key technology of MC for development and design in manufacture. PC selects the ones from a set of pre-defined and modularized components, and confirms the connection between them according to some fixed rules, in order to get the products fitting the design requirements and satisfying the customer's personal demands.For the modern products become more and more complex, implementing the PC tasks by computer has become one of the most popular means of research and application of PC technology. With the rapid development of network technology, the research and application of PC technology has made great progress.Since 1990s, AAAI, ECAI and IJCAI have held the meetings regularly about PC, which have attracted many famous universities and company's R&D staff to attend and have published a large number of good papers. With PC technology, application enterprises have winned more customer resources, reduced the cost of production and improved the market competitiveness. Many successful application cases appeared in manufacture, power, traffic, architecture, dress, software development, and so on.In the background of PC technology, the thesis conducts a research on several key technologies of PC, including PC knowledge representation, PC reasoning, PCM (product configuration manager) design, and the integration of PCM & PDM (product data management).The main contributions and results included in the thesis are as follows:Firstly, the research and application of PC technology is introduced. The appearance and development process of PC technology are introduced. The main research methods adopted by PC technology are summed up, including the rule-based, logic-based, constraint-based, resource-based, structure-based and ontology-based methods. Their current research and characteristics are pointed. The work task of PCM is analyzed. The application of PCM is classified. On the basis of above-mentioned points, the main research contents of PCM are discussed. These contents are the base of further research of this thesis.Secondly, the PC knowledge representation method is studied. The structure-based knowledge representation method is widely adopted by manufacture. It can clearly express the structure relations among the parts. However, its description ability to the configuration constraint is relatively weak. To this problem, a PC knowledge representation method for manufacture is provided in this thesis. Comparing with other methods, it has the following characteristics: First, the rule-based knowledge representation method is imported to the structure-based method. The logic information is separated from the structure information in the PC knowledge. That is, the structure information is expressed by the structure-based method and the logic information is expressed by the rule-based method. Furthermore, the configuration logic model is built. Second, the object-oriented design method is imported to the design for configuration rule and the weight-constraint design method is imported to the design for configuration parameter. This knowledge representation method can well describe the structure and logic information in the PC knowledge, and has good expansibilities and strong expressiveness for configuration constraint. It is easy to be understood and mastered by the field experts and implemented by the application systems.Thirdly, the PC reasoning method is studied. The configuration reasoning is mainly executed with the product tree-structure characteristics in the traditional structure-based PC knowledge representation method. However, because its expression ability to the configuration constraint among the parts is relatively weak, the configuration reasoning ability is greatly reduced along with the increasing of the configuration problem complexity. To this problem, a configuration reasoning graph is provided based on the knowledge representation method given in this thesis. Then, a configuration reasoning method is provided with the data-driven depth-first graph search strategy, which is used to solve the configuration constraint problem among the parts. Its arithmetic description is also given. The method has the following characteristics: First, the configuration parameter value is assigned based on weight constraint. Thus, those invalid data to solve configuration results are filtrated out with weight constraint. It can revise the data-driven direction and heighten the data-driven validity and the reasoning ability. Second, different resolution methods are provided according to the different reasons of rule match conflicts. It can decrease the number of configuration rules and the complexity of configuration rules. Furthermore, it reduces the search space of PC reasoning and simplifies the logic of PC reasoning. Comparing with the traditional methods, this method can increase the reasoning efficiency in a certain degree.Fourthly, the design of PCM for manufacture is studied. The present theory research of PCM can well direct its application design and development. However, it lacks systematic research in the following two problems: one is the subsequent disposal to the configuration results in PCM. The other is the system framework design to PCM on a developing view. To the two problems, some improvements are made in the thesis. First, the PCM work fashion is improved. The PCM task is divided into three sub-tasks: modeling, configuring and registering, and the PCM application modules are correspondingly divided into modeler, configurater and register. The registering task and register answer for the subsequent disposal to the configuration results. Second, the PCM system framework design is given based on the MVC design method. Its models have low coupling degree and are maintained easily. Furthermore, a human-computer interaction oriented configuration task executing algorithm is put forward, which enhances the enforceability of the PCM design model. The above-mentioned design has a certain reference to the PCM development in manufacture.Fifthly, the integration of PCM & PDM is studied. The integration has preferable practicability, which avoids the waste of enterprise resources and the redundancy of information. Current researches pay more attention to the close integration in the function layer and less attention to it in the data layer, and the platform portability of configuration logic is not so perfect. To this problem, an integration framework and UML model design for the PC knowledge representation are given in the thesis. First, the framework is given based on the PDM informatization management, which realizes the close integration in the function layer. It supports persistence, version, privilege, role, user, item and workflow managements of PDM to product configuration. Second, the UML model design is given based on the part and product structure designs in PDM system, which realizes the close integration in the data layer. It separates the configuration logic information from the structure information in configuration knowledge. It lowers the coupling degree between the both and supports the platform portability. The UML model design also helps to develop the PCM system independently.Sixthly, the research results of this thesis are applied in the actual system. The PCM in Qiming"Phosphor/cPDM"system is designed and developed with the above-mentioned studies. The PCM in Phosphor/cPDM is mainly used in the automobile manufacture. The PCM in Phosphor/cPDM includes three sub-modules: Configuration Modeler, Configuration Specification Editor and Product Register. It can express complex configuration logic, provide flexible and friendly customer interface, and realize the close integration with the PDM system.The study results of the thesis, especially of the PC knowledge representation, the configuration reasoning, the PCM design, and the integration of PCM & PDM, are of both theoretical and practical benefit to further researches in PC technology for manufacture.