Trajectory tracking control of a Macro-Micro welding robot based on the vision navigation

A trajectory tracking control scheme of a Macro-Micro welding robot based on the vision navigation is proposed. The robot system is composed of macro manipulator and micro manipulator attached to the tip of the macro part. Based on the visual sense, the robot is capable of effectively realizing the teaching mode and real-time tracking mode simultaneously, which is quite advantage to achieve better seam tracking performance. When using the teaching mode, several points sampled by the visual system can be used to build seam model that can be regarded as a standard seam curve of trajectory plan motion of the macro part. The correction bias control of the micro manipulator is to compensate the seam errors between standard seam position and real measures. The coordinated motion control is adopted to keep the joint values of the micro manipulator in desired range. Experiments results show the effectiveness of these control schemes and the good tracking results are obtained.