Research Of Key Technologies In Reconfigurable CAPP System Based On Process Knowledge Grid

Computer Aided Process Planning (CAPP) system will promote the capability of process design and management of manufacture enterprises. The trends of the rapid production and globalization in manufacture require on-demand CAPP systems. However, reuse-orient CAPP is one of the difficulties in this research field because of the complexity and individuation. Supported by National 863 Projects, and integrated with the requirement of distributed process designing and rapid reuse of process knowledge, relevant theories, key technologies and applications of reconfigurable CAPP system and dynamic process knowledge management architecture are studied to support the rapid reconstruction of CAPP applications. The main research contents and achievements are as follows:1. The theory on the Process Knowledge Management and the reconfigurable CAPP application structure are proposed based on the analysis on the current situation of the research, existing problems and trends of CAPP systems.2. Based on the analysis of the origination, hierarchy, classification and characters of the process knowledge, the Active Process Knowledge Grid Architecture (APKGA) is proposed. Through APKGA, process knowledge can be defined in uniform descriptions. The model can produce hot knowledge lists and distribution rules, which will be a basis in simulating knowledge evolution. The formalization standards based on XML of the APKGA objects are defined, and the samples of common process knowledge assemblies are provided.3. The disciplines of the memory and the forgetting of human brains are utilized for the process knowledge acquisition. The Compound Memory-Forgetting Model (CMFM) based on the mechanism of iterative excitations and long term learning is proposed. The mathematical solution, parameter estimation and features of the model are studied, as well as the equivalent and simplify for computer simulation, and the acquiring, updating and forgetting procedure in simulation are provided. On this basis, the evolvement of a single process knowledge unit is inspected and verified with test cases.4. Combined with the features of APKGA, complex process knowledge evolution procedures, including process knowledge decomposition, process knowledge self-organization, clustering and aggregation, are defined and studied. Cases of process knowledge extraction and process document are provided.5. Combined with service-oriented technologies, the CAPP.Net system is proposed and developed. With encapsulations and hierarchical platform structures, common CAPP functions are decomposed into service units and reassembled together through dynamic service list. Key technologies, including process generating, resource management, and embedding digital signatures, are studied. The CAPP.Net system has been applied in manufacture enterprises.The research on process knowledge reuse and reconfigurable network based CAPP systems provided theories, methods and models for the implementation of on-demand process knowledge management and rapid reorganization of CAPP applied systems.