Development Of Large Machine Basic Parts Cutting Database System Based On Feature

Machine basic parts are very important for machine tool.They are the foundation and the framework of the whole machine tool,and they are also the major parts of machine tool body. For increasing processing efficiency,improving processing quality and reducing processing costs of large machine base parts,combined with the project requirements,on the basis of the feature modeling technology and the case-based reasoning technology, this article researched and developed the large machine basic parts cutting database prototype system.The system can intelligent match the appropriate cutting parameters for the parts.The requirements analysis of the system were done firstly, and the input parameters and the output parameters were determined.On the basis,by the concept design and the logical design of the system,the whole design scheme of the system was got.Combined with the content of the function modules divided in the system, the system of function interfaces were developed,and the large machine basic parts cutting database prototype system based on feature was developed. By running the examples, all the functions of the system were verified.During the process of the system design, the expandability of the parts feature was considered fully to make the system have a certain flexibility.Based on group technology, machining features of the box parts were summarized from the shape feature.On the basis, the machining features of the large machine basic parts were extracted.On the foundation of existing part feature classification methods, the part features of the large machine basic parts was divided into shape features,precision features and material features.The routine shape feature classification method was improved,the shape feature of the parts was constituted by the three layers structure which has a dependency relationship.On the basis of the feature-modeling technology,combining the content of the part feature classification,with the modeling method based on feature design, the feature model of the large machine basic parts was built.According to the theories and methods of case-based reasoning,on the basis of determined the expression form and composition attributes of thesingle case,the new retrieval method combined the nearest-neighbor approach and the knowledge-based approach was proposed.According to the feature model of the large machine basic parts determined retrieval sequence of the case attributes.For enhancing the reasoning efficiency, the various attributes of the case were coding.Using the flexible code encoding increased the flexibility of the system. According to the original similarity function deduced the feature matching similarity algorithm.On the basis of the above research content,the feature matching which was on the basis of case-based reasoning was realized.