Coordinated Motion of Playback Robot and Positioning Table.

Abstract

It is well known that by introducing coordinated motions of an arc welding robot and a positioning table, most desirable arc welding performance could be obtained. The reason is that the coordinated motions enabled the welding torch and the workpiece to have desirable configurations considering effects of the gravity. In order to realize coordinated motions, a high accuracy of the robot is required. Therefore, force sensors and vision sensors to compensate mechanical errors are often introduced.In this paper we describe a system to realize coordinated motions by employing a teaching-playback robot. Due to the feature of teaching-playback robots that mechanical errors are readily compensated by the operator during the teaching task, satisfactory coordinated motions could be realized without using any additional sensors. Furthermore, a teaching method to specify coordinated motion is described. By using this teaching method, teaching tasks of coordinated motions could be performed effectively. Experimental results reveal the applicability of our robot system to the arc welding tasks.