N. Olgaç; "Stability of Linear Time Invariant-Time Delayed Systems..."
STABILITY OF LINEAR TIME INVARIANT-TIME DELAYED
(LTI-TDS) SYSTEMS AND PRACTICAL IMPLICATIONS
(LTI-TDS) SYSTEMS AND PRACTICAL IMPLICATIONS
Prof. Nejat Olgac
Mechanical Engineering Department
University of Connecticut, USA
Mechanical Engineering Department
University of Connecticut, USA
1) A Novel Method for Assessing the Stability of Time Delayed LTI Systems (LTI-TDS).
The discussion covers a novel treatment of this general class of LTI-TDS. Both retarded type and neutral TDS are considered. There are two interesting propositions, which give rise to this approach. They are under an umbrella paradigm called the ‘Cluster Treatment of Characteristic Roots (CTCR)’. CTCR brings a resolution on the subject, which has been investigated since the 70s. It suggests some systematic steps for assessing the number of unstable roots for a time delayed LTI system as an explicit function of the delay. Real time control issues will also be discussed. Nontrivial deployment of CTCR to multiple time delayed cases is also discussed.
2) A Tour of Practical Applications of Time-Delayed Control
Several practical cases are considered. a) Use of time delay as a stabilizing tool in target tracking (animation), b) Single axis arm control with delayed data and counter-intuitive observations (experiment), c) A concept of actively tuning vibration absorbers, the “Delayed Resonator” (experiment) are explained.
Biography
Nejat Olgaç:Dr. Eng. Sci. Columbia Univ 1976, M.Sc. Technical Univ. of Istanbul, Turkey 1972, both in Mechanical Engineering. He is a professor with the Mechanical Engineering Department of the University of Connecticut since 1981. His research interests are in robust nonlinear controls, active vibration absorption, time delayed systems, micromanipulation in bio-engineering. Dr . Olgac holds three patents (1995-96-99) on the Delayed Resonator active vibration suppression technique. He is the director of Advanced Laboratory for Robotics, Automation and Manufacturing (ALARM) at UConn. Dr. Olgac was Visiting Professor at INRIA (Sophia Antipolis, France) 1988-89, SEW Eurodrive Fellow - Guest Professor at Technical Univ. of Munich, Germany in 1995-96 and Visiting Professor at Harvard University 2002-03). He is an associate editor for the ASME Trans. of Dynamic Systems, Measurement and Control, and the guest editor of the Special Issue of JDSMC on Time Delayed Systems (scheduled for 2003). He is currently on the Chairman of the Executive Committee of the ASME Dynamic Systems and Control Division. Prof. Olgac is a Fellow of ASME and Senior Member of IEEE.
July 21, 2005, 11:00, G025
The discussion covers a novel treatment of this general class of LTI-TDS. Both retarded type and neutral TDS are considered. There are two interesting propositions, which give rise to this approach. They are under an umbrella paradigm called the ‘Cluster Treatment of Characteristic Roots (CTCR)’. CTCR brings a resolution on the subject, which has been investigated since the 70s. It suggests some systematic steps for assessing the number of unstable roots for a time delayed LTI system as an explicit function of the delay. Real time control issues will also be discussed. Nontrivial deployment of CTCR to multiple time delayed cases is also discussed.
2) A Tour of Practical Applications of Time-Delayed Control
Several practical cases are considered. a) Use of time delay as a stabilizing tool in target tracking (animation), b) Single axis arm control with delayed data and counter-intuitive observations (experiment), c) A concept of actively tuning vibration absorbers, the “Delayed Resonator” (experiment) are explained.
Biography
Nejat Olgaç:Dr. Eng. Sci. Columbia Univ 1976, M.Sc. Technical Univ. of Istanbul, Turkey 1972, both in Mechanical Engineering. He is a professor with the Mechanical Engineering Department of the University of Connecticut since 1981. His research interests are in robust nonlinear controls, active vibration absorption, time delayed systems, micromanipulation in bio-engineering. Dr . Olgac holds three patents (1995-96-99) on the Delayed Resonator active vibration suppression technique. He is the director of Advanced Laboratory for Robotics, Automation and Manufacturing (ALARM) at UConn. Dr. Olgac was Visiting Professor at INRIA (Sophia Antipolis, France) 1988-89, SEW Eurodrive Fellow - Guest Professor at Technical Univ. of Munich, Germany in 1995-96 and Visiting Professor at Harvard University 2002-03). He is an associate editor for the ASME Trans. of Dynamic Systems, Measurement and Control, and the guest editor of the Special Issue of JDSMC on Time Delayed Systems (scheduled for 2003). He is currently on the Chairman of the Executive Committee of the ASME Dynamic Systems and Control Division. Prof. Olgac is a Fellow of ASME and Senior Member of IEEE.
July 21, 2005, 11:00, G025