Reconstructing Skewed Quadric Surfaces from the Three Orthographic Views of Engineering Drawings

Quadric surfaces are commonly adopted in mechanical parts as boundary surfaces and they might be intersected by planes in skew positions．This paper proposes an algorithm to recognize and reconstruct the skewed quadric surfaces based on the analysis of their projection features．The proposed algorithm first detects their intersections with the adjacent planes according to their projection traces on three orthographic views, athen retrieves the skewed quadric surfaces and calculates their geometry．The precise intersection lines between the complete quadric surfaces and the adjacent planes are then determined and the topologies of the surfaces are constructed in the 3D object space． The proposed approach could handle the skewed quadric surfaces in arbitrary positions, awhich extends the domain of shape reconstruction based on engineering drawings．The method has been implemented in a solid reconstruction system, aand experimental results demonstrate its usability．