Integral quadratic constraints

Researchers: U. Jönsson, in cooperation with C-Y Kao, University of Melbourne, A. Megretski (M.I.T), and A. Rantzer, LTH.

We are involved in an effort to develop the framework of Integral Quadratic Constraints (IQCs) for robustness analysis of uncertain and nonlinear systems. The main idea behind this framework is to use a convex set of quadratic forms (IQC) to characterize uncertainty, nonlinearities, disturbance signals and other hard-to-handle components. The analysis results in a convex optimization problem involving the nominal dynamics and the convex set of IQCs. It is applicable for analysis of general complex networked systems. We have contributed to theory development, development of IQC characterizations of several uncertainty classes, computational theory, algorithm development, and to software development.