To extract machining feature from lightweight model effectively, after analyzing the data structure of lightweight model, a feature-oriented lightweight model was established, and a machining feature recognition method based on lightweight model was proposed. Firstly, the boundary representation(B-rep) of the lightweight model was set up by designing the algorithm of extracting geometrical information from lightweight model. Then the AAG was constructed by giving a method of judging adjacency relationship between surfaces. And then a new AAG decomposition method was put forward, which successfully resolved both protrusion features and depression features. Finally, a sample application was developed to illustrate the feasibility and validity of the method proposed. 

machining feature, feature recognition, lightweight model, boundary representation, attributed adjacency graph(AAG)

为有效提取轻量化模型中的加工特征,在分析轻量化模型的基础上,建立了面向特征的轻量化数据模型,并提出了基于轻量化模型的加工特征识别方法。通过设计轻量化模型的几何信息提取算法,建立了轻量化模型的边界表示模型;给出了一个判断表面间邻接关系的算法,建立了零件的属性邻接图;通过对属性邻接图进行二次分解,实现了对凸出类特征和凹陷类特征的识别。最后,通过一个实例验证了方法的可行性和有效性。

加工特征, 特征识别, 轻量化模型, 边界表示, 属性邻接图