research

        other recent selected publications (for full publication list, see here)

            - Passive decomposition of multiple mechanical systems under motion coordination requirements,

                D. Lee & P. Y. Li, IEEE Transactions on Automatic Control (submitted, pdf)

            - Passivity-based switching control for stabilization of wheeled mobile robots, D. Lee,

                 IEEE Transactions on Automatic Control (submitted, pdf)

                 Also, to appear in Robotics: Science & Systems 2007 (pdf)

                 *single robot stabilization [avi] / multirobot coordination [avi]

            - Passivity and energy in the control of biped locomotion, M. W. Spong, J. K. Holm & D. Lee,

                 IEEE Robotics & Automation Magazine (to appear, pdf)

                 *video: walking speed changing while maintaining limit-cycle trajectory [avi]

            - Passive bilateral control and tool dynamics rendering for nonlinear mechanical teleoperators,

                 D. Lee & P. Y. Li, IEEE Transactions on Robotics, vol.21, no.5, p.936-951, 2005 (pdf)

                 *video: 2-dof nonlinear telerobot [mpg]         

            - Passive bilateral teleoperation with constant time-delay, D. Lee & M. W. Spong,

                 IEEE Transactions on Robotics, vol.22, no.2, p.269-281, April 2006 (pdf)

            - Stable flocking of multiple inertial agents on balanced graphs, D. Lee & M. W. Spong,

                 IEEE Transactions on Automatic Control (to appear, pdf)

                  * unstable flocking when inertial effects are neglected [avi]

                  * stabilized flocking with inertial effects considered [avi]

                  * stable flocking of many agents [avi, avi, avi]

            - Agreement with non-uniform information delays, D. Lee & M. W. Spong,

                 2006 American Control Conference (pdf), Automatica (submitted, pdf)   

                  * homogeneous agents agreement (all second-order) [avi]

                  * heterogeneous agents agreement (two are now first-order) [avi]  

                  * agreement of many agents [avi]

            - Bilateral teleoperation of a wheeled mobile robot over delayed communication networks, D. Lee,

                 O. Martinez-Palafox & M. W. Spong, 2006 IEEE Int'l Conf. on Robotics & Automation (pdf)

                   *video 1: view from U. of Illinois (Urbana) [wmv]

                   *video 2: view from U. of New Mexico (Albuquerque: shrieks from camera) [wmv]

            - Bilateral teleoperation of multiple cooperative robots over delayed communication networks: 

                 theory, D. Lee & M. W. Spong, 2005 IEEE Int'l Conf. on Robotics & Automation (pdf)

                   *videos: maintaining rigid formation [avi]/ cooperative manipulation [avi]

                                (green is master robot/other threes are slave robots)

            - Passive decomposition approach to maneuver and formation control of multiple agents with inertias,
                 D. Lee & P. Y. Li, ASME Journal of Dynamic Systems, Measurement & Control (to appear, pdf)

                   *video 1: spacecraft formation flying (attitude & translation) [avi]

                   *video 2: string-stability under disturbance [avi]

                   *video 3: hierarchical control of nine agents [avi]

                   *video 4: hierarchical control of nine agents with temporary actuation failure [avi]