Frequency domain considerations and visual servo control in a port-Hamiltonian and Euler-Lagrange setting.
Prof. Jacquelien Scherpen (University of Groningen, Netherlands)
SYSTEMS AND CONTROL SERIESDATE: 2013-08-30
TIME: 10:00:00 - 11:00:00
LOCATION: RSISE Seminar Room, ground floor, building 115, cnr. North and Daley Roads, ANU
CONTACT: JavaScript must be enabled to display this email address.
ABSTRACT:
In this talk, we will consider two frequency domain methods that are well known for improving the performance of linear systems. For nonlinear systems those methods have not been considered yet because there is no theoretical justification for their use. Here we put a standard notch filter in the port Hamiltonian framework. By having such a port-Hamiltonian description it is proven that the notch filter is a passive system. The notch filter can then be interconnected with another (nonlinear) port-Hamiltonian system, while preserving the overall passivity property. By doing so we can combine a frequency-based control method, the notch filter, with the nonlinear control methodology of passivity-based control.
In addition, we study a well known passivity based controller in the Euler Lagrange framework that is only feeding back position measurements, and provide an interpretation of a lead-compensator structure, resulting in tuning rules for the passivity based controller.
Finally, if time permits, we will take a port-Hamiltonian approach to visual servo control of a pick and place system. The resulting control strategy depends only on the camera states and a region of attraction for asymptotic stability can be found.
BIO:
Jacquelien M.A. Scherpen received her M.Sc. and Ph.D. degree in Applied Mathematics from the University of Twente, The Netherlands, in 1990 and 1994, respectively in the field of Systems and Control. Her thesis was entitled: "Balancing for nonlinear systems". From 1994 to 2006 she was at Delft University of Technology, The Netherlands. First, she was a post-doc both in the Circuits and Systems and Control Engineering groups of Electrical Engineering, followed by an assistant (1995) and associate (1999) professorship in the Control Engineering group. In 2003 the group merged into the Delft Center for Systems and Control of Delft University of Technology, The Netherlands. Since September 2006 she holds a professor position at the University of Groningen in the Industrial Technology and Management department of the faculty of Mathematics and Natural Sciences. She has held visiting research positions at the Universite de Compiegne, France, SUPELEC, Gif-sur-Yvette, France, the University of Tokyo, Japan and the Old Dominion University, VA, USA. Her research interests include nonlinear model reduction methods, realization theory, nonlinear control methods, with in particular modeling and control of physical systems with applications to electrical circuits, electro-mechanical systems and mechanical systems. Industrial and space applications are included in her interests. She has been an associate editor of the IEEE Transactions on Automatic Control, and of the International Journal of Robust and Nonlinear Control. Currently, she is associate editor of the IMA Journal of Mathematical Control and Information and she is in the editorial board of the International Journal of Robust and Nonlinear Control.
