Paper:
Robust Vibration Control of a Flexible Robot Arm Carrying an Uncertain Load That Causes Bending/Torsional Coupling
Toru Watanabe, Kohsuke Yamamoto, Kohei Takamura,
and Kazuto Seto
Dept. of Mechanical Engineering, College of Science & Technology, Nihon University, 1-8 Kanda Surugadai, Chiyoda-ku, Tokyo 101-8308, Japan
This paper presents the design procedure of a robust H∞ controller for bending/torsional coupled vibration of a flexible robot arm. If the arm does not hold the center of the load, it possesses bending/torsional coupled vibration modes that may not be precisely identified. In this research, we use H∞ robust control design with structured uncertainties used to describe the model error in the coupling of bending/torsional vibration. We set up an experimental system and identify two physical models using Seto’s modeling method. An H∞ controller is designed using these models and control simulations and experiments are conducted. Our results demonstrate the feasibility and effectiveness of the proposed modeling and controller design method.
- [1] A. Maekawa, T. Kawamura, and Y. Tanaka, “Control of a 2-Link Flexible Arm (2nd Report, Evaluation of the Robust Stability against Vibrations of an Arm’s Configuration and a Tip Mass and related Experiments),” JSME Int. J., Ser. C, 57-539, pp. 2321-2327, 1991 (in Japanese).
- [2] H. Sakamoto, and K. Nonami, “Gain-Scheduled H∞ Control Based System Design for Positioning and Vibration Control of Two-Link Flexible Arm,” JSME Int. J., Ser. C, 68-670, pp. 1753-1758, 2002 (in Japanese).
- [3] K. Seto, and S. Mitsuda, “A New Method for Making a Reducedorder Model of Flexible Structures Using Unobservability and Uncontrollability and Its Application in Vibration Control,” Proceeding of MOVIC’92, Yokohama, Vol.1, pp. 153-158, 1992.
- [4] J. C. Doyle, K. Glover, P. P. Khargonekar, and B. A. Fransis, “State-Space solutions to Standard H2 and H∞ Control Problems,” IEEE Transactions on Automatic Control, Vol.AC-34, No.8, pp. 831-847, 1989.
- [5] T. Watanabe, and K. Yosida, “Robust Vibration Control for a Flexible Structure Taking Account of Parameter Variations and Residual Dynamics,” Proceeding of the 5th International Conference on Adaptive Structures, pp. 387-396, 1995.
- [6] K. Seto, “Many Modes of Vibration Control for Flexible Structures using H-infinity Based Robust Control,” Proceeding of the Second Japan-Korea Symposium of Frontiers in Vibration Science and Technology, pp. 21-27, 1994.
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Copyright© 2004 by Fuji Technology Press Ltd. and Japan Society of Mechanical Engineers. All right reserved.