21 Novembre 2019, 14.00
salle des commissions
Campus St. Jérôme
In this talk, I will present various techniques of stabilization in finite time for perturbed and unperturbed chains of integrators. These issues arise in sliding mode control.
Joint work with M Harmouche and S Laghrouche.
21 Octobre 2019, 14.00
salle des commissions
Campus St. Jérôme
Modeling and Simulation methods have been used to better analyze the behavior of complex physical systems and it is now common to use simulation as a part of the scientific and technological discovery process. M&S advanced thanks to the improvements in computer technology, which, in many cases, resulted in the development of simulation software using ad-hoc techniques.
Formal M&S appeared in order to try to improve the development task of very complex simulation systems. Some of these techniques proved to be successful in providing a sound base for the development of discrete-event simulation models, improving the ease of model definition and enhancing the application development tasks; reducing costs and favoring reuse.
The DEVS formalism is one of these techniques, which proved to be successful in providing means for modeling while reducing development complexity and costs. DEVS model development is based on a sound theoretical framework. The independence of M&S tasks made possible to run DEVS models on different environments (personal computers, parallel computers, real-time equipment, and distributed simulators) and middleware.
We will present a historical perspective of discrete-event M&S methodologies, showing different modeling techniques. We will introduce DEVS origins and general ideas, and compare it with some of these techniques. We will then show the current status of DEVS M&S, and we will discuss a technological perspective to solve current M&S problems (including real-time simulation, interoperability and model-centered development techniques). We will show some examples of the current use of DEVS, including applications in different fields.
We will finally show current open topics in the area, which include advanced methods for centralized, parallel or distributed simulation, the need of real-time modeling techniques, and our view in these fields.
23 Mai 2019, 14.00
salle des commissions
Campus St. Jérôme
Le but de ce séminaire est de présenter la conception et la commande de robots bipèdes. De l’analyse des modèles de ces robots et de celle de la marche, on peut déduire une commande hybride non linéaire stabilisant la marche. A partir du cas le plus simple d’un robot plan au cas des bipèdes 3D, on arrive progressivement à déterminer les conditions nécessaires pour élaborer la commande d’un robot humanoïde ainsi que de résumer les principales caractéristiques de ces robots.
25 Avril 2019, 14.00
salle X133
Campus Toulon
Moving-horizon estimation (MHE) for dynamic systems relies on the simple idea of using a limited amount of most recent information to estimate the state variables at the current time instant, thus ensuring intrinsic robustness. The literature on MHE is vast since it has followed a favorable trend induced by the success of the model predictive control. MHE has been applied to estimation of many kind of systems in different application fields. The talk will concern the various approaches adopted to perform MHE to systems with linear, nonlinear, and switching dynamics and different optimization tools.
28 Mars 2019, 14.00
salle des commissions, bât Polytech
Campus de St. Jérôme
Le problème est initialement posé, et résolu par J-P. Gauthier et I. Kupka [G-K] pour résoudre le problème d’existence d’entrées analytiques qui rendent observable un système analytique. Dans cet exposé, il s’agit d’une part d’étendre le résultat existant, d’autre part de réduire la preuve. Pour résoudre ce problème [G-K] ont fait appel à la stratification d’un certain cône tangent en tant qu’ensemble sous-analytique. Dans ce travail, je propose une preuve basée toujours sur la stratification des ensembles sous-analytique, mais qui ne nécessite pas le passage par la stratification du cône tangent.
21 Mars 2019, 14.00
salle des commissions, bât Polytech
Campus de St. Jérôme
Recent results pertaining to the stabilizations of systems with long delays in the input will be presented. In particular, the so-called prediction model approach and prediction approaches will be described and applied to time-varying systems. Fundamental new tools used to established the results will be explained. In particular, a technique of stability analysis called « trajectory based approach » and its recent extensions will be presented.