A study on torus type impossible figures based on graph and knot theory

Abstract

A method of representating multibar figures and their subclass torus figures is proposed, and an automatic drawing system for torus figures based on graph and knot theory is presented. The multibar type graph that is an abstract concept of multibar figures is defined by the junction graph that represents the connections of the lines. The link structure is defined for torus type graph to be able to classify torus figures and to show geometrical constraints with edges and faces of them. The presented system and theorems give a basic tool for experiments on visual psychology and development of intelligent recognition systems.