摘要
为提高ＣＡＤ／ＣＡＭ系统的描述能力和效率，本文提出一种基于特征设计和参数设计的零件模型。该模型采用了一系列新的表示方法，包括辅助点线面表示、工作坐标系表示、截面轮廓和轨迹表示、实体表示、特征表示、特征关系表示和零件模型表示。辅助点线面用于定位特征。坐标系使用矩阵与参数两种方式表示。特征采用几何信息与工程信息分离表示。实体模型采用参数和Ｂ－ｒｅｐ两种表示。特征关系采用二叉树表示。零件模型采用三层表示：特征关系层、特征层和详细描述层。这些表示方法使零件模型的参数化易于实现。最后，本文讨论了如何使用特征构造零件模型及如何使用参数修改零件模型。
To improve the capability and efficiency of the CAD/CAM system, this paper presents a part model based on features and parametric technology. Adopted in the model are a series of new representations including auxiliary point, line and plane, work coordinate system, section profile and trajectory, solid model, features, feature relation between features and part model. Auxiliary point, line and plane are used as the datum of features. Work coordinate system is constructed by mixing matrix representation and parametric representation. A feature consists of geometrical information and engineering information stored separately. Solid are modeled by the use of both parametric and B-rep. Relationship between features are defined by binary tree. Part mode is described in three layers: feature relation layer, feature layer and detail description layer. Using these representations makes the parametric part model easy to be generated. Finally, the process of design-with-features and modification of the part model are discussed.
出处
《工程图学学报》
CSCD
1997年第1期26-33,共8页
Journal of Engineering Graphics
关键词
特征设计
参数设计
实体造型
变量设计
CAD/CAM
design-with-features, dimension, parametric design, solid modeling, variational design
