Research And Application On Hierarchical Modeling And Reuse Technology Of Product Virtual Maintenance Simulation Process

This dissertation presents a theory and method of hierarchical modeling of product virtual maintenance simulation process, great progress has been made in the research of reuse technology in the field of virtual maintenance simulation process through hierarchical decomposition. On the basis of the theoretical research, a product virtual maintenance management and reuse system is developed, which can support the designer to manage the information and dataset of virtual maintenance simulation process. It reaches a good effect of accomplishing product virtual maintenance design and simulation in the virtual environment through the reuse of similar maintenance process.The dissertation is organized as follows:In the first chapter, the dissertation introduces some key enabled technologies which are used in the virtual maintenance, and reviews the history and present status. It presents the research purpose and content of product virtual maintenance simulation process against the deficiency existing in the virtual maintenance.In the second chapter, the dissertation presents a method of hierarchical decomposition of virtual maintenance simulation process through compare and analysis of field maintenance and virtual maintenance architecture. Also, It presents a method of object-based action units assortment according to the contact process and extent of virtual man to the object. Then, analyzed the reusability of every hierarchy to find which have reuse values.In the third chapter, a method of digraph-based hierarchical modeling of product virtual maintenance simulation process is presented. If the maintenance has enough maintenance resources, PERT chart is used for process modeling, and if the maintenance resources are deficiency, stochastic Petri net is used. For the action units which can reuse, this dissertation gives standardization expression based on object attribute and constraint relation. After that, the data structure of maintenance process database is designed to help for reuse of dataset.In the forth chapter, the dissertation researches the reuse process of virtual maintenance simulation process. After searching similar virtual maintenance simulation process based on searching constraint group, it calculates the similarity between the old and new process. An algorithm of similarity calculation based on PERT chart structure and attribute property is presented. At last, the similar process is reused successfully.In the fifth chapter, the frame of product virtual maintenance management and reuse system is built. The dissertation introduces main function modules of user interface layer. At last, the system gets a successfully application in maintenance simulation and reuse of several equipments.In the last chapter, summarizes the contents and the achievements of this dissertation, and then points out the place which needs to be improving and further research direction.