Rule-Based Geometrical Reasoning For The Interpretation Of Line Drawings
Elizabeth T. Whitaker, Michael N. Huhns · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1986
The design of a knowledge-based system for inferring the three-dimensional structure of an object based only on three orthogonal views of it is presented. The three views are line drawings obtained from digitized two-dimensional images of the front, top, and one side of the object. The system attempts to make the same deductions as would be made by a draftsman observing these line drawings. Although the information in only three views is insufficient to uniquely characterize an object, a draftsman is still able to infer a reasonable three-dimensional interpretation by making appropriate assumptions about hidden surfaces and using intuition about the structure of objects in three-space. The system incorporates similar intuitive knowledge and reasoning techniques which enable it to make the same assumptions. The knowledge which is used by the system is encoded as productions in the rule-based language OPS5. The system successfully produces a correct three-dimensional description for many simple polyhedral objects. It can be easily expanded to include new polyhedral objects simply by adding new production rules.