Einladung zum Vortrag im Kolloquium Technische Kybernetik

 Flexible Control Lyapunov Functions

Prof. Mircea Lazar
Technische Universiteit Eindhoven
Eindhoven · The Netherlands

    Zeit: Donnerstag, 26.11.2009 · 14 Uhr
Ort: IST-Seminarraum 3.243 · Pfaffenwaldring 9 · Campus Stuttgart-Vaihingen

Abstract

A central tool in systems theory for synthesizing control laws that achieve stability are control Lyapunov functions (CLFs). Classically, a CLF enforces that the resulting closed-loop state trajectory is contained within a cone with a fixed, predefined shape, and which is centered at and converges to a desired converging point. However, such a requirement often proves to be over-conservative. In this research we propose a novel idea that improves the design of CLFs in terms of flexibility, i.e. the CLF is permitted to be locally non-monotone along the closed-loop trajectory. The focus is on the design of optimization problems that allow certain parameters that define a cone associated with a standard CLF to be decision variables. In this way non-monotonicity of the CLF is explicitly linked with a decision variable that can be optimized on-line. Conservativeness is significantly reduced compared to classical CLFs, which makes flexible CLFs more suitable for stabilization of constrained discrete-time nonlinear systems and real-time control. Already successful applications of flexible CLFs include the design of robust MPC schemes of low complexity, stabilization of delay difference inclusions and stabilization of networks of nonlinear systems with dynamic coupling.
The talk will cover to some extent the following areas of research: (i) design of flexible CLFs for discrete-time nonlinear systems; (ii) Lyapunov theory for delay difference inclusions with an application to networked control systems; (iii) decentralized and distributed algorithms for stabilization of large scale networks of systems.

Biographical Information

• PhD from the Technical University of Eindhoven, Netherlands, September 2006: “Model predictive control of hybrid systems: Stability and robustness” – “Best thesis in Europe on Networked and Embedded Control” EECI-HYCON award for the period 2006-2007;
• PhD from the Technical University “Gh. Asachi” of Iasi, Romania, September 2009. “Predictive control algorithms for nonlinear systems” – title received with the Summa cum laude distinction;
• Outstanding reviewer of IEEE Transactions on Automatic Control, 2003, 2004, 2005.
• VENI grant (personal grant for excellence in research) from the Netherlands Organization for Scientific Research (NWO), 2008 – 2011;
• IPC committees: 3rd IFAC Conference on Analysis and Design of Hybrid Systems, 2009; 48th IEEE Conference on Decision and Control, 2009;
• Member of the Conference Editorial Board of the IEEE Control Systems Society, since July 2009.