Abstract: Ensemble control originated from quantum spin systems and has found many applications across various disciplines in science and engineering. In this talk, we Introduce and address a novel control problem, namely, the problem of structural controllability for continuum ensembles of linear time-invariant systems. We assume that all the individual linear systems of an ensemble are sparse and they share the same sparsity pattern. Controllability of the ensemble system is, by convention, the capability of using a common control input to simultaneously steer every individual systems in it. A sparsity pattern is said to be structurally controllable if it admits at least a controllable linear ensemble system. We provide a graphical condition that is necessary and sufficient for a sparsity pattern to be structurally controllable. Like other structural problems, the property of being structural controllable is monotone. We provide a complete characterization of minimal sparsity patterns as well.

Bio: Xudong Chen is an Assistant Professor in the Department of Electrical, Computer, and Energy Engineering at the University of Colorado Boulder. Previously, he was a postdoctoral fellow in the Coordinated Science Laboratory at the University of Illinois, Urbana-Champaign. He obtained the B.S. degree from Tsinghua University, Beijing, China, in 2009, and the Ph.D. degree in Electrical Engineering from Harvard University, Cambridge, Massachusetts, in 2014. He was an awardee of the 2020 Air Force Young Investigator Program. His research interests are in the area of control theory, stochastic processes, optimization, game theory and their applications in modeling, analysis, control, and estimation of large-scale complex systems.