Vibration Suppression Control Using Vibration Node of Articulated Robot with Multiple Vibration Modes

A high-speed, highly accurate positioning operation is required for industrial robots. However, residual vibration is generated in high-speed operation because industrial robots are cantilever structure. It takes the long settling time to the positioning operation. Acceleration feedback control is effective for vibration control. In the robot with two or more modes of vibration, the vibration mode besides targeted mode is excited by the difference of the vibration phase. In this paper, the phase relation and the vibration mode shape are clarified, and it aims at the control of the two or more modes using vibration node of the mode. The vibration modes are clarified by a modal analysis, and the vibration is controlled by the acceleration feedback. Using the vibration node of the mode stabilizes the difference of the phase of the first mode and the second mode. The effect of vibration control is verified by the experiment.