| With productive manufacturing model changing from large-scale mode to customization mode, conventional CAPP system could not fit to multivariate manufacturing environment any longer. The ability of fast response is the insistent requirement of the customization manufacture mode. This dissertation presents the reuse theory of process plans and correlative methods. Based on the reuse theory, the process planing schemes are put forward for rotational and case parts. A system of process planning design is developed, and is applied effective to CIMS promotion subject (863-511-910-211/02) of state 863 high-tech program.In the 1st chapter, on the basis of analysis of the characteristic of customization production, the technical demand of reusing process plans for customization manufacture is discussed. The present research situation of system structure and process plans reusing technology in process planning are summarized in detail. Then, the background and content of this dissertation are described briefly.In the 2nd chapter, the modeling method of manufacture-oriented structure unit is put forward, and has been used to implement design reuse. The structure unit encapsulates manufacturing and planning data, and provides basic modular for product design and process planning reuse. With the discussion of application mode of group process , the layering design method of process plans reuse is introduced. This method is applied to different level of product modeling and different parts. To obtain the theory base of process planning design of rotational and case parts, the work fashion of process plans reuse system is built.In the 3rd chapter, by analyzing typical parts of mechanical product, the processing technical characteristics of rotational and case parts are generalized. The reason that causes multiplicity of process planning is analyzed in detail, and the descriptive method for multi-planning is provided. The hierarchical indexing model of process plans reuse base is composed of type level and case level, and the encoding rule and sorting method for type level are provided.In the 4th chapter, the hierarchical information model of rotational part is built. In order to overcome the shortage of rigid-coding, flexible-coding rule is put forward based on the part processing property. Similarity decision rule and three level retrieval strategy are presented based on part flexible code, which provides accurate cases matching. In order to generate process plan for dissimilar parts, structure degenerating match algorithm is provided. The algorithm andinference rule combine to generate part plan.In the 5th chapter, aiming at the case part of complex structure, the information description method based on foundation-structure-unit and azimuth-structure-unit-tree is presented, and hierarchical information model of case part is defined. Based on process plan reuse layering, unit-based similarity is applied to process plan design of structure unit, and the coding architecture of structure unit and grading matching strategy are presented. The modification algorithms for similar plan and method of process planning reasoning generating for new structure unit are provided. The sufficiency function is built for genetic algorithm based on constraint rule, and the genetic /tabu algorithm is introduced to process aggregating. The feasibility and efficiency of the algorithm are verified by the result of example.In the 6th chapter, on the basis of theoretic research above, a process plans reuse design system is developed. The system's architecture, characteristics and main modular are introduced. Resource guidance and recursive generation techniques of process picture sheet are presented, and have been applied to this system.In the 7th chapter, all achievements of this dissertation are summarized, and the further work in the future is given.
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