Rotational Parts Of The Process Design Cbr System And Its Key Technologies

Because of the bad practicability of process planning expert system, in order to improve process planning efficiency and accuracy, considering the intelligence and practicability, case-based reasoning theory is applied to process planning in this thesis. This thesis is to do research on application of CBR to process planning and its key technologies.Taking the rotational parts as example, an approach of case representation in case-based reasoning process planning is presented. It contains parts information expression and process representation . Two branch tree of feature is adopted to express parts information, while two branch tree of machining process and machining step is adopted to express process. Formulas are constructed to calculate the similarity coefficients. Strategies and algorithms are worked out to retrieve and match the most promising candidate cases. The detailed matching information which make the case modification easy to realize are carefully recorded. Rule-Based approach is adopted in case modification of the system. Algorithms are worked out to decide feature whose process needs to be deleted and whose process needs to be added. How to accomplish process planning case modification is also presented.Based on above-mentioned research and considering enterprise needs, CAPP system which is independent of CAD system is programmed based on Visual C++6.0 and SQL Server 2000. At last, running case of CAPP system is presented in order to validate the system. Process which is planned by this system accords with real process, which validates indirectly the feasibility of technology and theory of the thesis.