Vibration suppression of a flexible robot manipulator with a lightweight piezo-composite actuator

The increasing demand for high-speed performance and low energy consumption has necessitated the design of lightweight mechanical systems. The active vibration suppression of a flexible manipulator is important in many engineering applications, such as robot manipulators and high-speed flexible mechanisms, because the flexibility of lightweight manipulators induces a vibration problem. Frequently, the optimal parameters determined for a certain control algorithm might not cover a wide range of operating conditions. Hence, we have proposed and developed a lookup table control method for a flexible manipulator that can tune itself to optimal parameters on the basis of the initial maximum responses of the controlled system and a genetic algorithm. The genetic algorithm is used to search for optimal parameters with regard to positive position feedback and thereby minimizes the objective functions determined from the initial maximum responses. Our lookup table, which has the optimal parameters of the positive position feedback as a function of the initial maximum responses, can be used in a real-time control algorithm. Recommended by Editorial Board member Hyoukryeol Choi under the direction of Editor Jae-Bok Song. This work was supported by the Korea Research Foundation under grant KRF 2006-005-J03302 and the Korea Science and Engineering Foundation under grant KOSEF R0A-2007-000-20012-0. Van Phuoc Phan received the BS (2006) from the Department of Aeronautical Engineering, HCM University of Technology, Vietnam. Currently, he is a Master student at the Department of Advanced Technology Fusion, Konkuk University in Seoul, Korea. His interests are structural dynamics of small systems, smart structure and material, and finite element analysis. Nam Seo Goo graduated from the Department of Aeronautics Engineering of Seoul National University with honors in 1990, and got master and Ph.D. degrees in Department of Aerospace Engineering at the same university in 1992 and 1996, respectively. His Ph.D. degree was on the structural dynamics of aerospace systems. As soon as he got a Ph.D. degree, he entered the agency for defense development as a Senior Researcher. After four years’ service, he joined Department of Aerospace Engineering in Konkuk University, Seoul, Korea in 2002, currently serving an Associate Professor of Department of Advanced Technology Fusion. His current research interests are structural dynamics of small systems, smart structure and material, and MEMS applications. Hoon Cheol Park received his BS (1985) and MS(1987) degrees from Seoul National University in Seoul, Korea and Ph.D.(1994) degree from the University of Maryland at College Park, MD, USA. He joined the Department of Aerospace Engineering, Konkuk University in Seoul, Korea in 1995, and he is currently a Professor in the Department of Advanced Technology Fusion. His professional experience includes Kia Motors (1986–1988) and Korea Aerospace Research Institute (1994–1995). His specialty is the finite element analysis and recent research topic is mainly biomimetics.