Research And Development Of Intelligent CAPP-NC System For Blades Based On CBR

In order to solve the problems of large repeatability,low efficiency and long process document preparation in the process design and NC instruction generation of enterprise blades,this dissertation introduced CBR technology into blade process design,and developed the intelligent CAPP-NC system for blades based on CBR on the basis of UG software.The main research contents and achievements are as follows:(1)On the basis of analyzing and summarizing the structure,classification and process design characteristics of the blades,the structure framework and working process of the blade intelligent CAPP-NC system based on case-based reasoning are proposed.The functions of system information description module,instance retrieval and matching module,instance correction module,process document output module and instance library management module are described in detail.(2)The case-based reasoning technology is studied,and the key technologies in this system are introduced.1)Through the research and analysis of the blade process design,the key attributes that have important influence on the process design process are extracted from the blade feature information.Based on object orientation,the composite knowledge representation method combining frame structure representation method and generation rule is adopted to describe the information of the blade process example;2)Using the nearest neighbor strategy as the retrieval strategy of the blade process,a hierarchical retrieval model of the first retrieval,depth retrieval and similarity ranking was established.A global similarity algorithm based on weighted nearest neighbor algorithm,a local similarity classification algorithm based on feature data type,and a combined weighting method based on analytic hierarchy process(AHP)and maximum deviation method(MAF)were adopted,the weight coefficient of the characteristic attributes of the blade process is calculated according to the analytic hierarchy process(AHP);3)The combination of system automatic correction and human-computer interaction correction is adopted to carry out the example correction.(3)According to the study of theory and system key technology,Microsoft Visual Studio 2015 as the system development platform,Visual C++ MFC interface development tools,Access database for blade process instance library platform,using UG secondary development technology is developed based on CBR blade intelligent CAPP-NC system,and introduces in detail the system key module of the program development process.(4)A certain blade process design of an enterprise is selected as an example to demonstrate the workflow of each module of intelligent capp-nc system based on CBR and verify the accuracy and reliability of the system.This system can obtain the most similar to the current design of the blade process example,to achieve the automatic correction of the process process card and NC instruction interaction correction,greatly reduce the repetitive work in the process of blade process design and NC instruction generation,improve the work efficiency of process designers,to improve the competitiveness of enterprises has important significance.