Nothing is as Practical as a Good Theory: Model-Free Control

Rien de plus utile qu'une bonne théorie : la commande sans modèle

Michel Fliess (1) , Cédric Join (2, 3) , Samer Riachy (3, 4)

1 LIX - Laboratoire d'informatique de l'École polytechnique [Palaiseau]
2 CRAN - Centre de Recherche en Automatique de Nancy
3 NON-A - Non-Asymptotic estimation for online systems
4 ECS-Lab - Électronique et Commande des Systèmes Laboratoire

The experience gained with numerous successful applications permits to revisit some points of model-free control. The numerical differentiation of noisy signals may be replaced by a real time parameter identification which is much simpler. The strange ubiquity of classic PIDs is explained as well as the almost universal utilization of ultra-local models of order 1. We show that even with a partially known model the utilization of an intelligent PI controller remains profitable. Two examples, an inverted pendulum and a heat exchanger, seem to confirm the superiority of model-free control with respect to sliding modes control and techniques stemming from infinite-dimensional systems, such as delays or partial differential equations. Our paper is illustrated by several computer simulations.

Mots clés: model-free control

Mots clés: intelligent controllers; PID; identification; inverted pendulum; heat exchanger; sliding modes; delays; partial differential equations

Domaines: Automatique; Automatique / Robotique; Optimisation et contrôle [math.OC]

Michel Fliess, Cédric Join, Samer Riachy. Rien de plus utile qu'une bonne théorie : la commande sans modèle. 4èmes Journées Doctorales / Journées Nationales MACS, JD-JN-MACS, Jun 2011, Marseille, France. ⟨hal-00581109v2⟩