Robust Hinf tracking control design for a class of switched linear systems using descriptor redundancy approach

International audienceThe work presented in this paper concerns the output feedback tracking control for a class of Switched Linear Systems (SLS) with external disturbances. The main result is based on a descriptor redundancy formulation of the closedloop dynamics. The proposed approach allows the avoiding of the crossing terms appearance between the controller's and the switched system's matrices leading to easier Linear Matrix Inequality (LMI) formulation. Multiple Lyapunov functional methods are utilized to the stability analysis and controller design. By introducing the Proportional-Derivative (PD) controller, a robust Hinf output feedback tracking performance has been satisfied. The efficiency of the proposed synthesis procedure has been illustrated by a numerical example

Diagnosis of a class of switched linear systems : an approach based on robust observer

Ce travail de thèse porte, en premier lieu et principalement, sur le diagnostic à base de modèle d’une classe de SLC (Systèmes Linéaires à Commutations). Une problématique récurrente dans ce type de problème concerne la prise en considération de façon explicite les deux aspects, continu et discret, constituant un SLC. Dans ce cadre, nous avons proposé une méthodologie de détection et de localisation de défauts qui combine les outils initialement dédiés au diagnostic des systèmes continus et d’autres spécifiques aux SED (Systèmes à Evénement Discrets). L’approche proposée est conçue autour de trois modules : deux types de générateurs de résidus (issus de l’Automatique continue) et un estimateur en-ligne de l’état discret, appelé diagnostiqueur (issu de l’Automatique événementielle). Notre diagnostiqueur utilise les deux types de résidus, provenant de la partie continue, afin d’identifier le mode de fonctionnement du SLC et d’isoler les défauts de capteurs. Les résidus utilisés pour la localisation des défauts de capteurs sont générés à travers un générateur développé autour d’un schéma DOS (Dedicated Observer Scheme) à base d’observateurs hybrides,à la fois robustes vis-à-vis des entrées inconnues et sensibles aux défauts de capteurs. En second lieu, sur la base des résultats obtenus à l’aide de l’approche de diagnostic développée, nous avons proposé une approche préliminaire de synthèse de lois de commande tolérantes aux défauts de capteurs stabilisante via un retour d’état. Cette approche permet de préserver les performances nominales du système (situation non défaillante)en présence d’un défaut de capteurs. L’idée consiste à reconfigurer le retour d’état en remplaçant le vecteur d’état estimé à partir d’une sortie en défaut par un autre estimé à partir d’une sortie saine. La redondance des estimations est assurée dans cette approche par un banc d’observateurs hybrides robustes qui fournit plusieurs estimations correctes des vecteurs d’état et de sorties.This thesis focuses, in first and foremost, on the model-based diagnosis of a class of SLC (Switched Linear Systems). The basic idea is to consider the continuous and discrete aspects, forming an SLC, explicitly.In this context, we proposed a methodology for detecting and locating faults that combines the tools originally dedicated to the continuous systems and the DES (discrete event systems) diagnosis. The proposed approach is designed around three modules: two types of residual generators (from the continuous Automatic) and anon-line estimator of the discrete state, called diagnoser (from the event Automatic). Our diagnoser uses the residual generators issue from the continuous part to identify the SLC mode and isolate sensor faults.Residues used for fault location sensors are generated through a generator developed around a scheme DOS(Dedicated Observer Scheme) based on hybrid observers. These observers are robust vis-à-vis the unknown input and sensitive to sensor faults. Secondly, based on the obtained results using the previous diagnosis approach, we proposed a preliminary approach for fault-tolerant state-feedback control law synthesis. This approach preserves the nominal performance of the system (as non-defaulting) in the presence of defective sensors. The idea is to reconfigure the state feedback by replacing the state vector estimated from defected output by another estimated from non-defected one. Redundancy estimates is provided in this approach by a bank of robust hybrid observer that provides several accurate estimates of state vectors and outputs

The impact of non-uniform bifunctional catalyst for the isomerization of n-hexane in fixed bed catalytic reactor

International audienceCatalytic reforming is a very important process in chemical industry. The aim of this process is to transform treated naphtha (paraffins, olefins, naphtens, aromatics) into reformates with a better yieldin aromatics such as benzene, toluene, and xylenes (BTX) that are very important petrochemical materials and providing a high octane index. In this work, a mathematical model is proposed to investigate the influence of the concentration and the non-uniform distribution of the catalytic sites on the performances of an isothermal fixed bed reactor with axial dispersion and mass transfer resistance. This model is applied to the naphtha catalytic reforming network. The simulation of the model for a particular chemical reaction network showed that the catalyst activity and selectivity depend on the balance between the number, per unit volume, of the active sites and the way they are distributed throughout the pellet

Recent Advances on Multisensor Attitude and Heading Estimation: Fundamental Concepts and Applications

International audienceIn 1965, Grace Wahba introduced the problem of attitude estimation within the estimate of satelliteattitude and aerospace applications. Over the past few years, there has been an increasing interestin multidisciplinary research on multisensor attitude estimation technology. This interest is motivated by the versatility of the diverse areas of application such as aerial and underwater navigation,pedestrian navigation, biomedicine, motion analysis, and smartphone applications. Attitude estimation consists in the determination of rigid body orientation in 3D space (principally in terms ofEuler angles, rotation matrix, or quaternion). This research area is a multilevel, multifaceted processinvolving the automatic association, correlation, estimation, and combination of data and information from several sources. Another interest consists in the fact that redundant and complementarysensor data can be fused and integrated using multisensor fusion techniques to enhance systemcapability and reliability.Data fusion for attitude estimation is therefore a research area that borrows ideas from diversefelds, such as signal processing, sensor fusion, and estimation theory, where enhancements areinvolved in point-of-view data authenticity or availability. Data fusion for attitude estimation ismotivated by several issues and problems, such as data imperfection, data multimodality, datadimensionality, and processing framework. As a majority of these problems have been identifedand heavily investigated, no single data fusion algorithm is capable of addressing all the aforementioned challenges. Consequently, a variety of methods in the literature focuses on a subset of theseissues.The idea of this book comes as a response to the immense interest and strong activities in thefeld of multisensor attitude estimation during the past few years, both in theoretical and practicalaspects. This book is targeted toward researchers, academics, engineers, and graduate studentsworking in the feld of sensor fusion, fltering, and signal processing for attitude estimation.This book, Multisensor Attitude Estimation: Fundamental Concepts and Applications, capturesthe latest data fusion concepts and techniques for attitude estimation drawn from a broad arrayof disciplines. It is intended to provide the reader with a generic and comprehensive view of contemporary data fusion methodologies for attitude estimation, as well as the most recent researchesand novel advances on multisensor attitude estimation task exploring the design of algorithms andarchitectures, benefts, and challenging aspects, as well as a potential broad array of disciplines,including navigation, robotics, biomedicine, and motion analysis. These issues arise from the datato be fused, imperfection and diversity of sensor technologies, and the nature of the applicationenvironment. The issues that make data fusion for attitude estimation a challenging task, and whichwill be discussed through the different chapters of the book, are related to (1) the nature of sensorsand information sources (accelerometer, gyroscope, magnetometer, GPS, inclinometer, etc.); (2) thecomputational ability at the sensors; (3) the theoretical developments and convergence proofs; and(4) the system architecture, computational resources, and fusion level.With contributions from world’s leading fusion researchers and academicians, this book consisting of 31 chapters, is roughly divided into two sections. Each chapter is complete in itself and canbe read in isolation or in conjunction with other chapters. This book is introduced by Grace Wahbawith a brief historical note on attitude estimation problem. In Section I, Chapters 1 through 3 aredevoted to some preliminaries on attitude representations, rotations, kinematics, and dynamics. InSection II, Chapters 4 through 31 focus mostly on the main theories and novel advances in multisensor fltering for attitude estimation with several experimental tests and showcase advancements suchas aerial navigation, motion analysis, and satellite.We are grateful to all the contributors for making their valuable contributions to this book, andwe expect to offer here a good balance between academic and industrial researches in this book.We sincerely hope that this book will be a source of inspiration for new concepts and applications and stimulate further the development of attitude estimation architectures. We also acknowledgethe technical and editorial assistance provided by CRC Press and its staff, which helped to improvethe quality of this work

Design of a Robust Tracking PD Controller for a Class of Switched Linear Systems with External Disturbances

International audienceThis paper concerns the design of a robust output feedback tracking controller for a class of Switched Linear Systems (SLS) subject to external disturbances. The proposed synthesis approach, based on a descriptor redundancy formulation, allows to avoid of the crossing terms appearance between the switched Proportional-Derivative (PD) controller's and the switched system's matrices. Using the multiple Lyapunov functional methods, a robust H¥ output feedback tracking performance has been formulated in terms of set of Linear Matrix Inequality (LMI). The effectiveness of the proposed synthesis procedure has been illustrated by a numerical exampl

Diagnostic d'une classe de systèmes linéaires à commutations (approche à base d'observateurs robustes)

Ce travail de thèse porte, en premier lieu et principalement, sur le diagnostic à base de modèle d une classe de SLC (Systèmes Linéaires à Commutations). Une problématique récurrente dans ce type de problème concerne la prise en considération de façon explicite les deux aspects, continu et discret, constituant un SLC. Dans ce cadre, nous avons proposé une méthodologie de détection et de localisation de défauts qui combine les outils initialement dédiés au diagnostic des systèmes continus et d autres spécifiques aux SED (Systèmes à Evénement Discrets). L approche proposée est conçue autour de trois modules : deux types de générateurs de résidus (issus de l Automatique continue) et un estimateur en-ligne de l état discret, appelé diagnostiqueur (issu de l Automatique événementielle). Notre diagnostiqueur utilise les deux types de résidus, provenant de la partie continue, afin d identifier le mode de fonctionnement du SLC et d isoler les défauts de capteurs. Les résidus utilisés pour la localisation des défauts de capteurs sont générés à travers un générateur développé autour d un schéma DOS (Dedicated Observer Scheme) à base d observateurs hybrides,à la fois robustes vis-à-vis des entrées inconnues et sensibles aux défauts de capteurs. En second lieu, sur la base des résultats obtenus à l aide de l approche de diagnostic développée, nous avons proposé une approche préliminaire de synthèse de lois de commande tolérantes aux défauts de capteurs stabilisante via un retour d état. Cette approche permet de préserver les performances nominales du système (situation non défaillante)en présence d un défaut de capteurs. L idée consiste à reconfigurer le retour d état en remplaçant le vecteur d état estimé à partir d une sortie en défaut par un autre estimé à partir d une sortie saine. La redondance des estimations est assurée dans cette approche par un banc d observateurs hybrides robustes qui fournit plusieurs estimations correctes des vecteurs d état et de sorties.This thesis focuses, in first and foremost, on the model-based diagnosis of a class of SLC (Switched Linear Systems). The basic idea is to consider the continuous and discrete aspects, forming an SLC, explicitly.In this context, we proposed a methodology for detecting and locating faults that combines the tools originally dedicated to the continuous systems and the DES (discrete event systems) diagnosis. The proposed approach is designed around three modules: two types of residual generators (from the continuous Automatic) and anon-line estimator of the discrete state, called diagnoser (from the event Automatic). Our diagnoser uses the residual generators issue from the continuous part to identify the SLC mode and isolate sensor faults.Residues used for fault location sensors are generated through a generator developed around a scheme DOS(Dedicated Observer Scheme) based on hybrid observers. These observers are robust vis-à-vis the unknown input and sensitive to sensor faults. Secondly, based on the obtained results using the previous diagnosis approach, we proposed a preliminary approach for fault-tolerant state-feedback control law synthesis. This approach preserves the nominal performance of the system (as non-defaulting) in the presence of defective sensors. The idea is to reconfigure the state feedback by replacing the state vector estimated from defected output by another estimated from non-defected one. Redundancy estimates is provided in this approach by a bank of robust hybrid observer that provides several accurate estimates of state vectors and outputs.REIMS-SCD-Bib. electronique (514549901) / SudocSudocFranceF

Design of a Robust Observer-Based FDI Scheme For a Class of Switched Systems Subject to Sensor Faults

International audienceThis paper concerns the Fault Detection andIsolation (FDI) problem for a class of Switched Linear Systems(SLS) subject to sensor faults and unknown boundeddisturbances. The main work is based on the design of ageneralized switched observer scheme. The FDI problems havebeen solved by using a robust control techniques. A suitabletrade-off between the robustness to disturbances and thesensitivity to sensor faults was obtained. The main results arereformulated by using Linear Matrix Inequality (LMI)formulation. An example is included to illustrate the efficiency ofthe proposed approach

Design of a Robust Observer-Based FDI Scheme For a Class of Switched Systems Subject to Sensor Faults

International audienceThis paper concerns the Fault Detection andIsolation (FDI) problem for a class of Switched Linear Systems(SLS) subject to sensor faults and unknown boundeddisturbances. The main work is based on the design of ageneralized switched observer scheme. The FDI problems havebeen solved by using a robust control techniques. A suitabletrade-off between the robustness to disturbances and thesensitivity to sensor faults was obtained. The main results arereformulated by using Linear Matrix Inequality (LMI)formulation. An example is included to illustrate the efficiency ofthe proposed approach

Diagnosis of systems with multiple operating modes

Chapter 6International audienc

Diagnostic des systèmes à modes multiples de fonctionnement

National audienc