A Master-Slave Trajectory Generation and Relative Error Compensation Mechanisms for High-Accuracy Industrial Robot Collaboration

This paper proposes a collaborative trajectory generation and error compensation mechanism for two industrial robots controlled by one central controller, in order to achieve high accuracy collaborative task execution. For such tasks requiring high accuracy and synchronization of both robots, the emerging offline programming method is much more efficient than teaching and playback approach. However, the relatively lower absolute accuracy of industrial robot is an inevitable challenge for implementing the offline programmed trajectories directly. Therefore, the collaborative trajectory generation process is analyzed first. The kinematic chain of the closed tworobot system is formulated and illustrated in detail, in order to determine and calibrate relative parameters. Afterwards, the relative errors between the end-effectors of both robots are measured during the movement. A corresponding error compensation method is then proposed to correct the trajectories. Physical experiments are conducted with EFFORT ER15-1400 and INOVANCE IRB-R10 robots, to verify the effectiveness and robustness of the proposed method.