3D vision system for robot guidance with structured sine wave illumination

Abstract

A three-dimensional vision sensor that can be mounted on a robot arm in order to determine the profile and range characteristics of a diffuse object placed in its field of view is described. A sinusoidal intensity distribution is projected on the scene. Objects present in the scene deform the sinewave, resulting in its phase modulation. Analysis of an image recorded on a CCD (charge coupled device) or photodiode array camera yields object profile information. In a prototype version, a depth resolution of 0.2 mm has been achieved for objects situated about 1 m away from the camera. Performance criteria such as resolution, processing speed, and mechanical adaptability indicate that the system is suitable for use as a range/vision sensor in robot applications.