Conveyor Visual Tracking using Robot Vision

Robot conveyor tracking is a task in which a robot follows and obtains objects on a conveyor belt. Prior to obtaining an object from an automation line, a robot needs information about the object, such as its position, orientation, velocity, size, etc. Compared to ultrasonic sensors and infrared ray sensors, vision sensors can provide more information about the object on the conveyor belts. Generally, an object tracking system has several steps: obtaining an image, recognizing objects, and extracting information for object position and orientation. The object tracking process for a conveyor system should be fast enough to support a real-time environment. In this article we describe a robotic tracking system that uses vision information extracted from sequential image frames. For fast extraction of vision information we applied a difference image technique which carries out a subtraction operation between two sequential frames with a small time interval. This simple method is useful for obtaining information about an image when there are minimal background effects caused by the conveyor system. In this article we present some results of some experiments using an integrated robot conveyor, vision system, and robot user interface software.