Reconstruction of quadric surface solids from three-view engineering drawings

In this paper, a robust and systematic scheme that automatically interprets three-view engineering drawings as quadric surface mechanical parts is addressed. Initially a three-dimensional wire-frame, with no face information in it, is reconstructed from the three orthographic projections. Next, all candidate faces are found within the wire-frame, using a minimum-internal-angle searching method. Then, pseudo elements that could be generated from backprojection are detected and deleted using a decision-chaining method. Finally, all true faces are assembled to form an oriented three-dimensional object. Face orientation consistency is ensured using the Moebius rule. The entire algorithm has been implemented in C on a UNIX system and experimental results are shown. (C) 1998 Elsevier Science Ltd. All rights reserved.