| Modern high performance NC(Numerical Controller)system has been advancing toward an open embedded architecture. Rigorous real-time capability of embedded NC system under this trend leads to more complicated system design and development. Traditional development methodology for embedded NC system usually causes fragile reliability and reusability as well as lagged system tests, thus lowering efficiency of the whole developing process. Aiming at solving these problems, the dissertation conducts thorough researches on component-based model-integrated design approach. Based on the researches, a component-based system software architecture, a kind of development method for embedded NC system components and a model-to-code transformation framework are proposed in this dissertation.The main contributions of the paper include:Taking embedded NC domain properties, interactions between components as well as system requirements into accounts, the dissertation put forward an embedded NC domain specific software architecture based on connection management units and function blocks(FB) containers. Structures and mechanism of critical modules, such as events management unit, data management unit and FB container, are described in detail. The whole architecture features the mechanisms of event-driven invocation and data-shared link structures. The first-in-first-out event queue design guarantee the concurrent execution correctness, solving the problem of events missing; Data exchanging is managed by data connection management unit, the datashared link structure make sure of integrity as well as correctness, eliminating the phenomenon of dead-lock.Classification of functional components for embedded NC system is studied according to designed principles of functional components and domain characteristics for embedded NC system. Based on the structural and run-time characteristics of functional components, the paper fulfills the templates for code generations. Furthermore, a metadata-based templates expanding method using value assignments for component-to-code mapping is implemented. The proposed component developing method is validated by the design and implement of a multisect continuous thread interpolation algorithm function block.System code realization is the key technology of implementation of the software framework based on the model integration. A method of code realization according to the requirements of hierarchical structure of systems which is appropriate for code generation of multi-node embedded NC models. Embedded NC Code Generation Framework(ENCCGF) for embedded NC with framework template and various mapping algorithms is designed according to the general code generation of models and the implementation methods of reconfiguration.Lastly, the software framework is verified by two NC systems whose structures are similar but functions different. The system application model is built in the NC domain graphic modeling environment and the code is generated automatically by using the code generator and the component this paper proposed. Two different NC is built of which one is for slotting machine of carbide micro milling-cutter of PCB, the other for two-axis lathe. The functional and performance test is carried out which validates the performance stability of auto-generated NC. The difference of the two NC systems on functions and performance validates that the requirement of easy-clipped and rapid-reconfigurable development of NC system is satisfied and a safe, rapid and effective solution for NC system based on component-based model integration is provided which can greatly improve the development efficiency and the ability of rapid respond to the market. |
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