Interpreting engineering drawings of polyhedrons

摘要

A system is discussed that restores solid models, or a set ofpolyhedra consistent with a given set of three orthographic views whichare input by using a facsimile device. Emphasis is on the description oftwo novel techniques: the line-segment extraction method and thepolyhedron restoration method. The line-segment extraction is performedby using a probe, a small fragment of line, which moves along thecentral axis of each line segment represented by a binary image.Therefore, the method does not require any preprocessing such as noiseelimination, or thinning of the given binary image. The polyhedronrestoration method uses a face-oriented approach, rather than theconventional wire-frame-oriented approach. The method is basically acombinatorial search procedure that finds all of the legal combinationsof possible faces