Recognition of polyhedrons with a range finder

摘要

A recognition procedure with a range finder has been developed for the eye of the ETL-ROBOT, an intelligent robot studied at the Electrotechnical Laboratory. The range finder employs a vertical slit projector which projects a light beam on the objects. While the beam is moved in a field of view, the picture at each instant is picked up by a TV camera. The distance to each point can be obtained by means of trigonometrical calculation. The information thus obtained is utilized for the recognition procedure, where (1) each point is classified into lines, (2) each line is classified into planes, (3) 3-dimensional position of each plane is calculated, and (4) the object is recognized by the relationship between planes. The method is applicable to objects whose surface is not uniformly colored. It also eliminates the effects of shadows because it directly measures the 3-dimensional positions of all points in the scene.