Memory Resilient Gain-scheduled State-Feedback Control of Uncertain LTI/LPV Systems with Time-Varying Delays

The stabilization of uncertain LTI/LPV time delay systems with time varying delays by state-feedback controllers is addressed. At the difference of other works in the literature, the proposed approach allows for the synthesis of resilient controllers with respect to uncertainties on the implemented delay. It is emphasized that such controllers unify memoryless and exact-memory controllers usually considered in the literature. The solutions to the stability and stabilization problems are expressed in terms of LMIs which allow to check the stability of the closed-loop system for a given bound on the knowledge error and even optimize the uncertainty radius under some performance constraints; in this paper, the $\mathcal{H}_\infty$ performance measure is considered. The interest of the approach is finally illustrated through several examples

A Full-Block S-procedure application to delay-dependent state-feedback control of uncertain time-delay systems

International audienceThis paper deals about the robust stabilization of uncertain systems with timevarying state delays in the delay dependent framework. The system is represented using LFR and stability is deduced from Lyapunov-Krasovskii theorem and full-block S-procedure. We derive sufficient conditions to the existence of a robust H-infinity state-feedback control law. As this sufficient condition is expressed in terms of nonlinear matrix inequality (NMI), we propose a relaxation based on the cone complementary algorithm which is known to lead to good results for such problems. We show the efficiency of our method trough an example

Une approche algébrique pour la commande des systèmes linéaires à retards de type neutre

International audienceOn s'intéresse dans ce papier à la définition d'un cadre algébrique pour la résolution de problèmes de commande pour les systèmes à retards de type neutre. Les problèmes de commande abordés sont la stabilisation, le suivi de trajectoire, et le rejet de perturbation. Le schéma de compensation retenu permet d'inclure une large classe de schémas linéaires et dynamiques. Chacun de ces problèmes est résolu de manière algébrique. On met en évidence la structure de compensation à partir d'invariants structurels, afin qu'une solution au problème mentionné ci-dessus existe. Enfin, un lien avec le principe du modèle interne est réalisé

Delay-Scheduled State-Feedback Design for Time-Delay Systems with Time-Varying Delays - A LPV Approach

International audienceThis paper is concerned with the synthesis of delay-scheduled state-feedback controllers which stabilize linear systems with time-varying delays. In this framework, it is assumed that the delay is approximately known in real-time and used in the controller in a scheduling fashion. First, a new model transformation turning a time-delay system into an uncertain LPV system is introduced. Using this transformation, a new delay-dependent stability test based on the so-called full block S-procedure is developed and from this result, a new delay-dependent stabilization result is derived. Since the resulting LMI conditions depend polynomially on the parameters, a relaxation result is then applied in order to obtain a tractable finite set of finite-dimensional LMIs. The interests of the approach resides in 1) the synthesis of a new type of controllers scheduled by the delay value which has a lower memory consumption than controllers with memory (since it is not necessary to store past values of the state), and 2) an easy consideration of uncertainties on the delay knowledge

Delay systems . From theory to numerics and applications.

International audienceThis volume offers the latest advances in the research of analyzing and controlling dynamical systems with delays. The contributions in this series are a collection across various disciplines, encompassing engineering, physics, biology and economics, and some are extensions of those presented at the IFAC conferences since 2011. The series is categorized in five parts: Stability analysis and control design - Networks and graphs - Time delay and Sample data systems- Computational and software tools - Applications. This volume will be a good reference point for researchers or PhD student in the field of delay systems, and it will be also a resource for control engineers who will find innovative control methodologies for relevant applications, from both theory and numerical analysis perspectives

Verticilliose de la tomate : expressions de la résistance générale chez deux lots d'origine sauvage

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Contrôle latéral partagé d'un véhicule automobile

Afin de faciliter la conduite et prévenir les accidents par sortie de voie, ce travail porte sur le développement d un dispositif d assistance au contrôle latéral de la trajectoire d'un véhicule automobile. L état de l art des travaux portant sur ce thème a mis en évidence la nécessité de mieux prendre en compte l interaction du conducteur avec l ensemble véhicule-route. Ceci nous a conduit à développer un mode de contrôle partagé basé sur l anticipation du risque et sur la prédiction des actions les plus probables du conducteur. Le travail de la thèse a été articulé principalement autour de deux axes : la modélisation cybernétique du conducteur dans sa tâche de contrôle latéral, et la conception du contrôle partagé de la direction sur la base du modèle global CVR (conducteur-véhicule-route). Un modèle du conducteur a été développé en cohérence avec les connaissances actuelles sur la sensorimotricité humaine. Ses paramètres ont été identifiés en utilisant des données expérimentales issues d un simulateur de conduite SCANeRTM. Ensuite, Deux stratégies du contrôle partagé ont été conçues et évaluées expérimentalement. La première (nommée CoLat1) se repose sur un principe similaire à celui des assistances LKS commercialisées à ce jour. Sa conception repose sur l utilisation d un modèle véhicule-route, et ne fait appel à aucun modèle du conducteur. Le partage n est fait que de la mise en œuvre en appliquant partiellement la commande qu il produit. La deuxième (nommée CoLat2) repose sur une conception tenant compte des modalités du partage de la conduite avec le conducteur. Sa conception repose sur l utilisation d un modèle global (CVR).In order to facilitate driving and prevent accidents due to lane departure, this thesis focuses on the development of an assistance device for lane keeping of a passenger vehicle. The review of the literature on this subject has highlighted the need for a better understanding of the interactions between the driver and the vehicle-road system. The goal is to develop a shared control mode based on the anticipation of risk and the prediction of the most probable actions of the driver. The thesis was mainly articulated around two axes: the cybernetic modeling of the driver in his task of lateral control, and the design of a shared steering control using a Driver-Vehicle-Road model (DVR). The proposed driver model is consistent with what is known about sensorimotor and cognitive control in humans. It has been identified from experimental data collected on a fixed-base driving Simulator SCANeRTM. Two shared control experimental studies were performed. The first (so-called CoLat1) is similar to already existing LKS systems. CoLat1 is primarily designed as an "electronic pilot" that has to drive alone the vehicle. Without using a driver model, it results from applying the H2-preview control synthesis to a vehicle-road model. Shared steering is performed only in the implementation phase: the control that it provides is partially applied to the steering wheel leaving the complementary control part to be applied by the driver. The second (so-called CoLat2) addresses a shared control resulting from applying the H2-preview control synthesis to the global model (DVR).NANTES-Ecole Centrale (441092306) / SudocSudocFranceF

Decoupling with stability for a class of linear systems via static state feedback

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