Inputting Constructive Solid Geometry Representations from Two-Dimensional Orthographic Engineering Drawings

摘要

An approach to inputting geometric representations of three-dimensional objects via two-dimensional orthographic views is introduced. The user has to identify, from an engineering drawing, the primitive volumes such as cuboids, cylinders and spheres, from which a model of the object is constructed. The identified primitives have to be input. Their dimensions and transformation parameters are derived by the program from a set of points input via a digitizer from two or three views of the object on a single drawing. Set operations for combining the primitives are input separately. Based on this input, the system produces a Constructive Solid Geometry (CSG) representation of the object. Input of a CSG representation appears simpler for the user and for the system than input of the object via a boundary representation in terms of points, lines, and faces.