The Benelux Meeting 2020 will host the following renowned invited speakers:

Luca Zaccarian

Title Plenary 1: Two decades of saturated linear feedback design via global and generalized sector conditions

Abstract: The saturation nonlinearity and its sector properties perhaps provided the main inspiration for absolute stability theory and sector properties. The advent of linear matrix inequalities (LMI) and their efficient solvers, in the mid 1990s, provided fertile ground for the development of LMI-based stability/performance analysis and control design algorithms for linear time-invariant (LTI) plants subject to input saturation. The corresponding results, mainly developed in the past 20 years, started from state feedback designs in parallel with anti-windup augmentations of predefined linear controllers, combined with quadratic Lyapunov certificates ensuring global exponential stability. The peculiar nature of saturation, however, is such that no LTI plant can be globally exponentially stabilized from a bounded input, unless it is already globally exponentially stable in open loop. Due to this fact, non-global (or generalized) sector conditions were invented, which opened up important questions about the size of (suitable estimates of) the basin of attraction. The ensuing generalized (or non-global) absolute stability conditions evolved over the past 15 years into several increasingly advanced control design and performance analysis algorithms for input-saturated systems. In this talk we provide an overview of these developments, covering the notion of generalized sector conditions, highlighting the limits of global versus local designs, the use of deadzone-induced piecewise smooth Lyapunov functions, the multi-agent extensions of the results for bounded synchronization of identical linear plants, and possible approaches for robust designs in the presence of uncertain plants.

Title plenary 2: Optimizing shifted equilibria for enlarged basins of attraction in quadratically stabilizing saturated feedback

Abstract: With asymmetric actuator saturation standard LMI-based approaches conservatively rely on symmetric sublevel sets of Lyapunov functions and conservative estimates based on the lowest saturation margin, between the available positive and negative actuator range. We describe here an approach based on an asymmetric feedback scheme focusing on shifted equilibria, selected via the solution of an optimization problem ensuring convergence to the origin of the shifted equilibrium. To enable the computational time required by the optimizer, we impose sampled-data updates of the shifted equilibria and cast our description within a hybrid dynamical systems formulation. Exact and inaccurate optimization algorithms are both allowed in our scheme, thus establishing interesting trade-offs between continuous-time dynamics and computationally expensive iterative discrete-time parametric optimization schemes. The results are illustrated on numerical examples and a toy experimental testbed.

Jacquelien Scherpen

Title Plenary: Krasovskii passivity based control and output consensus

Abstract: This talk presents novel passivity based control techniques by introducing the new passivity concept named Krasovskii passivity.  We investigate properties of Krasovskii passive systems and establish relations between four relevant related passivity concepts. We develop novel dynamic controllers based on Krasovskii passivity. The proposed controllers are applicable to a class of systems for which the standard passivity based controllers are not easily applicable. 
We then consider a class of resistive–inductive–capacitive (RLC) circuits and switched RLC  circuits modeled in the Brayton–Moser framework. Furthermore, we explore the usage of Krasovskii passivity for designing output consensus controllers. We apply these concepts to DC networks.

Margarita Chli

Title Plenary: Vision-based robotic perception

Abstract: will follow.

Mustafa Khammash

Title Plenaries: Cybergenetics: Theory and Implementation of Biomolecular Control Systems

Abstract: Homeostasis, the ability of living systems to maintain dynamic equilibrium, is a theme that runs across all of biology. Achieved through regulation, homeostasis ensures that regulated variables robustly adapt to uncertain environmental perturbations. What architectural constraints do such adapting networks obey? How can we exploit this knowledge to design and engineer novel synthetic control systems that achieve precision and robustness at the biomolecular level? In this talk, I will address these questions for networks that exhibit robust perfect adaptation (RPA).  I will show that there is a single fundamental biomolecular controller topology, based on integral feedback, that realizes RPA in arbitrary intracellular networks with noisy dynamics.  On the basis of this concept, I will describe genetically engineered synthetic feedback controllers in bacterial and mammalian cells and demonstrate their tunability and robust perfect adaptation properties.  These results provide conceptual and practical tools for the engineering of advanced genetic control systems, with application in industrial biotechnology and cell therapy.