关键词: CAD模型, 机械结构形态, 基本体形态, 基本体转换模型, 三维模型检索

Abstract: Aiming at the information incomplete problem of similarity measure feature for 3D CAD model,a model retrieval method based on Mechanical Structure Morphology (MSM) was presented.Through analyzing the basic features of MSM,a gold segmentation similarity coefficient was constructed to evaluate the similarity of primitive morphology location.The calculation rules of tangential vector and normal vector were proposed to compare the attitude similarity between two models,and the contour value of constraint trochoid was defined to calculate the contour similarity.A mass retrieval method of 3D CAD model was proposed based on the above similarity indexes,and a fine retrieval method was developed based on the similarities of MSM and primitive transformation model.The experimental results showed the presented retrieval method could compare the similarities of model shape,geometric dimension and topology information to improve the accuracy of the retrieval models,and its retrieval object was not only a 3D model but also a mechanical structure morphology.

Key words: CAD model, mechanical structure morphology, primitive morphology, primitive transformation model, 3D model retrieval