由三视图重建包含圆环面的形体

Reconstructing Solids with Tori from Three Orthographic Views Engineering Drawings

机械零件中的管道和曲面过渡通常都由圆环面构成.分析了圆环面在三视图中的投影性质,将圆环面不同方向投影中的具有独特性的二次曲线特征定义为它的主特征和次特征,以工程图标注的语义信息为辅,提出基于曲面特征识别的圆环面重建算法.该算法首先在三视图中识别圆环面特征,然后由特征计算曲面参数,最后构造拓扑结构.用该算法对带有管道和曲面过渡的实例进行了验证.

Tori are mainly used to construct pipes and blend surfaces in mechanical design. This paper proposes an algorithm of torus reconstruction based on feature recognition and semantics of engineering annotations. For tori, the projection characteristics in three orthographic views are analyzed; the unique conic features in different projections are accordingly defined as primary and secondary features. The presented algorithm first recognizes torus features in the views, and then calculates the geometry parameters based on the features. The topology of tori is finally constructed with respect to other surfaces. The reconstruction of solids with tori is implemented. The experimental results show that the algorithm is applicable to mechanical parts with various pipes and blending.