Feedback and Uncertainty
Speaker: Professor Lei Guo
Faculty Host: Professor Zhong-Ping Jiang
Feedback is known as a most basic concept in control. The quantitative understanding of the maximum uncertainty that can be dealt with by the feedback mechanism is a fundamental issue in systems and control theory. In this talk, we will give a survey of the recent results on some criterion and impossibility theorems concerning the maximum capability of the feedback mechanism in dealing with uncertainties for some basic classes of dynamical systems to be controlled. We will show how the structural uncertainty coupled with the nonlinearity of the discrete-time or sampled-data control systems give rise to fundamental limits to the capability of feedback, where we will also find that the sensitivity function will play an important role. Moreover, we will demonstrate how the Cramer-Rao-like inequality for dynamical systems and the Heisenberg Uncertainty Principle in quantum mechanics will result in the fundamental limits on the performance of feedback.
About the Speaker
Lei GUO received the B.S. degree in mathematics from Shandong University in 1982, and the Ph.D. degree in control theory from the Chinese Academy of Sciences (CAS) in 1987. He was a postdoctoral fellow at the Australian National University (1987-1989). Since 2003, he has been the President of the Academy of Mathematics and Systems Science, CAS. Dr. Guo is Fellow of the IEEE, Member of the Chinese Academy of Sciences , Fellow of the Academy of Sciences for the Developing World , Foreign Member of the Royal Swedish Academy of Engineering Sciences, and Fellow of International Federation of Automatic Control. He is currently the President of the China Society for Industry and Applied Mathematics, a Vice-President of the Chinese Association of Automation, and the Editor-in-Chief of Journal of Systems Science and Complexity. His current research interests include the maximum capability of feedback, multi-agent systems, complex adaptive systems and quantum control systems.