Understanding Drawings by Compositional Analogy

Patrick W. Yaner, Ashok K. Goel

We describe an analogical method for constructing a structural model from an unlabelled 2D line drawing. The source case is represented as a schema that contains its 2D line drawing, the lines and intersections in the drawing, the shapes in drawing, and the structural model of the device depicted in the drawing. Given a target drawing and a relevant source case, our method first constructs a graphical representation of the lines and the intersections in the target drawing, then uses the mappings at the level of line intersections to transfer the shape representations from the source case to the target, next uses the mappings at the level of shapes to transfer the structural model of the device from the source to the target. The Archytas system implements and evaluates this method of compositional analogy.