| In order to accurately and timely feedback the drawing error information in theprocess of design, proofing and reviewing in enterprise CAD usage and in the process ofhigh school CAD teaching, raise the level of intelligent comment in application,the thesisdeveloped a drawing comment modifying control based on AutoCAD using Visual Basiclanguage and ActiveX.The thesis includes firstly the design of three key-modules libraries--typical partsparametric design library, comment symbol library and drawings intelligent commentmodifying library. In the process of typical parts design, the thesis uses the idea ofparameterized design and can complete topology structure analysis, parts' parameterextraction and program design of several types of parts. So it can generate parts' drawingsautomatically by dimension driven. In the process of comment symbol library design, theprogram can generate automatically also the appearance and the usage method of eachcomment symbol through the drawings' errors type analysis and the collections of everycomment symbol. After all of that, the program can generate comment automatically usingdriven program written for each comment symbol operation process.The thesis includes secondly the design of intelligent comment modifying modulethrough feature extraction, graph feature recognition and the program called by parametricdesign module. And it includes also the design of feature recognition. Feature recognitionis an effective method to converse graphic information to manufacturing parameters. Itcan process images information using graph based feature recognition method. Accordingto the primitive topology structure of each part image, it can complete the component typediscriminant process through graphic preprocessing, feature extraction, primitive featurediscrimination, etc. Then the program extracts parameters' value needed for thecorresponding part type, generates a right drawing by modifying driven program with fewparameter changed, comparisons wrong drawing with the right one drawing just generated.Thus we got an intelligent comment drawings.The control can raise the level of intelligent comment by the application of graphfeature recognition method to the development of drawings' comment modifying software.The completion of this control will improve and perfect the methods and the functions ofAutoCAD drawing errors' correction. So, it can actualize intelligent drawing comment oftypical parts by man-machine interactive method, and can be used widely andconveniently in AutoCAD drawing. |
