Jee-Hwan RYU

Séminaire iSiR
Jee-Hwan RYU
BioRobotics Lab, School of Mechanical Engineering,
Korea University of Technology and Education, Cheonan, Rep. of Korea
 01 44 27 5141/5131
Fax: 01 44 27 51 45
Mardi 13 septembre 2011 à 14h30
Campus Jussieu, 4 place Jussieu, Paris
Pyramide ISIR, 56/65, niveau Jussieu, salle de réunion H20
Time Domain Passivity Approach
and its Applications to Haptic and Telerobotic Systems
One of the most significant problems in haptic interface design is to create a control system which
simultaneously is stable (i.e., does not exhibit vibration or divergent behavior) and gives high fidelity under
any operating conditions and for any virtual environment parameters. One fruitful approach is to use the
idea of passivity to guarantee stable operation. However, the major problem with using passivity for design
of haptic interaction systems is that it is too conservative. In many cases, performance can be poor if a fixed
damping value is used to guarantee passivity under all operating conditions.
In this talk, a new concept of energy based approach, so called Time Domain Passivity Approach
(TDPA), which inject adaptive virtual damping to satisfy the time domain passivity constraint will be
introduced from the basic concept to its applications to Haptic, Telerobotic Systems and even humanoid
First, the definition of the “Passivity Observer” (PO) which measures net energy flow in real-time, and
the “Passivity Controller” (PC), an adaptive dissipative element, will be reviewed. After we study the basic
concept, its applications to haptic and telerobotic systems will be introduced including time-delayed
teleoperation. In addition, efforts to generalize the TDPA to more general telerobotic systems even including
general motion control system will be briefly introduced.
At the end of the talk, I would like to comment on some recent extension and future issues.
Short bio:
Jee-Hwan Ryu received the B.S. degree in mechanical engineering from Inha University, Inchon, Korea,
in 1995, and the M.S. and Ph.D. degrees in mechanical engineering from Korea Advanced Institute of
Science and Technology, Taejon, Korea, in 1995 and 2002, respectively. From 2002 to 2003, he was a PostDoc. in the Biorobotics Laboratory in the Department of Electrical Engineering, University of Washington,
Seattle. While he was in U. of Washington, he was invited for three months as a visiting scientist from the
Institute of Robotics and Mechatronics, DLR in Munich. From 2003 to 2005, he was a research professor in
the Department of Electrical Engineering, Korea Advanced Institute of Science and Technology. He is
currently an Associate Professor in the School of Mechanical Engineering, Korea University of Technology
and Education. His research interests are control of haptics and telerobotic systems including autonomous
Sous la co-tutelle de
Institut des Syst"mes Intelligents et de Robotique
UPMC – CNRS / UMR 7222
Pyramide Tour 55 - Boîte courrier 173
4 Place Jussieu – 75252 PARIS cedex 05 – France
Tél. +33 (0)1 44 27 51 31 / 51 41 – Fax +33 (0)144 27 51 45