CAD Rapid Modeling Based On The Relationship Among Features

At present, there are some shortcomings in the CAD modeling, such as poorquality of models, low efficiency of modeling, little design reuse and awfulspecification in models. To solve these problems, relationship among features isresearched and applied to CAD rapid modeling. Besides, a special CAD rapidmodeling tool is developed. The main job of this thesis are as followed: (1)The relationship among features is turned into component-level relationshipand part-level relationship according to the influencing area. The component-levelrelationship among features has four forms, which are relationship based onparameters, linked elements, interpart feature and semantics information; (2)An automatic assembly design method is proposed.Assembly knowledge ispackaged with the idea of relationship among features, stack-style automaticassembly rule is advanced, the process of automatic assembly is fulfilled withautomatic assembly operation, and all of these are applied to pipes' modeling, whichchanges complex assembly to simple choice; (3)An interpart feature modeling method is proposed. Design knowledge ispackaged with the idea of relationship among features to make assembly and partmodeling conducted simultaneously. Moreover, a method of interpart featuremodeling with dynamic adjusting is proposed. In this way, the change of the part toconnect can drive the whole mechanical connecting element; (4)A special CAD rapid modeling tool supporting automatic assembly designand interpart feature modeling is developed on the unigraphics platform with theUG/Open routines and applied to certain type pipes in aerocraft. Good results aregained.