Explicit robustness and fragility margins for linear discrete systems with piecewise affine control law

Ngoc Anh Nguyen (1, 2) , Sorin Olaru (2, 3) , Pedro Rodriguez-Ayerbe (2) , George Bitsoris (4) , Morten Hovd (5)

1 CentraleSupélec
2 L2S - Laboratoire des signaux et systèmes
3 DISCO - Dynamical Interconnected Systems in COmplex Environments
4 University of Patras
5 ITK NTNU - Department of Engineering Cybernetics [Trondheim]

In this paper, we focus on the robustness and fragility problem for piecewise affine (PWA) control laws for discrete-time linear system dynamics in the presence of parametric uncertainty of the state space model. A generic geometrical approach will be used to obtain robustness/fragility margins with respect to the positive invariance properties. For PWA control laws defined over a bounded region in the state space, it is shown that these margins can be described in terms of polyhedral sets in parameter space. The methodology is further extended to the fragility problem with respect to the partition defining the controller. Finally, several computational aspects are presented regarding the transformation from the theoretical formulations to explicit representations (vertex/halfspace representation of polytopes) of these sets.

Keywords: PWA control; explicit robustness margin; fragility analysis

Domains: Automatic

Ngoc Anh Nguyen, Sorin Olaru, Pedro Rodriguez-Ayerbe, George Bitsoris, Morten Hovd. Explicit robustness and fragility margins for linear discrete systems with piecewise affine control law. Automatica, 2016, 68, pp.334-343. ⟨10.1016/j.automatica.2015.10.048⟩. ⟨hal-01408554⟩