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Ghassani, Rashad. "Commande Unifiée des Machines à Courant Alternatif." Electronic Thesis or Diss., Université de Toulouse (2023-....), 2024. http://www.theses.fr/2024TLSEP153.
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Les lois de contrôle des machines à courant alternatif, asynchrones et synchrones, sont aujourd'hui assez mûres. Le contrôle vectoriel est un cadre général pour la modélisation, l'analyse et le contrôle des machines à courant alternatif. Une approche de synthèse basée sur le modèle est souvent utilisée, et les paramètres de la loi de commande sont définis en fonction des paramètres de la machine. Un variateur de vitesse standard est utilisé dans la plupart des applications industrielles pour contrôler la vitesse du moteur alimenté par le réseau électrique. Dans ce cas, le variateur est appelé « variateur polyvalent ». Selon le type de machine à courant alternatif, un contrôleur spécifique est nécessaire. Pour ce faire, les fabricants de variateurs devront inclure différentes lois de commande dans leur variateur. Par conséquent, l'ajout de ces lois nécessitera beaucoup de mémoire et de capacité de calcul. En outre, le changement de type de machine modifierait la loi de commande. Ce problème peut entraîner de nombreuses difficultés, telles que des coûts d'installation plus élevés, des délais de mise en service et des réglages supplémentaires. C'est pourquoi la recherche d'un « universal drive » se poursuit depuis plus d'une décennie. Cette thèse présente une étude approfondie sur le sujet de la commande unifiée pour les machines à courant alternatif. Notre objectif est d'innover une loi de commande unifiée pour les machines électriques, en particulier les machines asynchrones et synchrones, à utiliser dans les futurs produits de variateurs de vitesse à usage général. Dans le cadre de cette thèse, nous abordons l'unification de la modélisation, la conception d'observateurs et les aspects de contrôle dans le contexte des machines à courant alternatif. Pendant des décennies, les modèles CA ont été étudiés séparément dans la littérature. Cependant, grâce aux similitudes entre les machines électriques, un cadre de modélisation unifié est proposé. Le modèle unifié repose sur des paramètres équivalents du stator facilement identifiables, quel que soit le type de machine. Sur la base du modèle unifié, une contribution clé a été apportée dans cette étude, à savoir la conception de trois nouveaux observateurs de flux unifiés pour suivre les positions du flux du rotor ou du stator, quel que soit le type de moteur. Grâce à l'observateur de flux unifié, une loi de commande vectorielle unifiée pour les machines à courant alternatif devient possible. Les données expérimentales vérifient la loi de commande proposée pour les machines à induction et les machines synchrones à aimant permanent. Théoriquement, la solution proposée met en évidence le potentiel d'une «universel drive » qui n'a besoin d'aucune information sur le type de moteur. Cependant, la loi de commande unifiée donne de mauvais résultats à faible vitesse, alors qu'une méthode de démarrage unifiée est nécessaireThe control laws of AC machines, asynchronous and synchronous, are pretty mature today. Vector control is a general framework for AC machines' modeling, analysis, and control. A model-based synthesis approach is often used, and the control law parameters are defined according to the machine parameters. A standard variable speed drive is used in most industrial applications to control the speed of the motor powered by the electrical network. In this case, the drive is called a “general-purpose drive”. Depending on the type of AC machine, a specific controller is needed. This will require the drive's manufacturers to include different control laws in their drive. Consequently, adding these laws will require a lot of memory and computing capacity. Furthermore, changing the machine type would alter the control law. This problem could lead to many issues such as higher installation costs, commissioning time, and additional tuning. For this reason, the search for a "universal drive" scheme has been going on for more than one decade.This thesis presents an in-depth study on the subject of unified control for AC machines. Our goal is to innovate a unified control law for electric machines, particularly asynchronous and synchronous machines, for use in future general-purpose variable speed drive products. As a part of this thesis, we address the unification of modeling, observer design, and control aspects in the context of AC machines. For decades, the AC models have been studied separately in the literature. However, thanks to the similarities between electric machines, a unified modeling framework is proposed. The unified model relies on easily identifiable stator equivalent parameters regardless of the specific type of machine. Based on the unified model, a key contribution was made in this study, which is the design of three novel unified flux observers to track rotor or stator flux positions, regardless of the motor type. Thanks to the unified flux observer, a unified vector control law for AC machines becomes possible. Experimental data verify the proposed control law for induction machines and permanent magnet synchronous machines. Theoretically, the proposed solution highlights the potential for a “universal AC motor drive" that doesn't need any information on the motor type. However, the unified control law performs poorly at low speeds, where a unified startup method is needed
2
Babatunde, Patrick O. "Norm-based methods in observer design." Thesis, Brunel University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340841.
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Stamnes, Øyvind Nistad. "Adaptive Observer for Bottomhole Pressure During Drilling." Thesis, Norwegian University of Science and Technology, Department of Engineering Cybernetics, 2007. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-8846.
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To satisfy the increasing petroleum consumption on a world wide basis there is a need to find new resources. As mature fields are drained, reservoir pressure falls, which again leads to tight pressure margins. To reduce down time due to hole stability problems (e.g. kicks) there is a demand for accurate control of the pressure profile in the well. As the pressure profile is not known and depends on unknown factors such as friction loss there is a need to estimate the pressure. In this thesis an observer that adapts to unknown factors, such as friction and density changes, and estimates the bottomhole pressure is presented. Furthermore, a parameter estimator for the bulk modulus in the annulus is developed as an extension to the observer to facilitate for future control design. Both designs are based on a third order model and provide rigid proofs of stability and convergence of the estimated pressure and parameters. The pressure estimate from the observer is shown to converge to the true pressure under reasonable conditions. For parameter estimates to converge to their true values conditions on excitation are presented. The observer and parameter estimator are tested in simulations and also on log data from a well drilled at the Grane field in the North Sea. Simulation results show that the observer performs very well during typical drilling procedures affecting choke valve opening, pump flows and drill string movements. The observer shows promising behavior when tested on log data from the Grane field.
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Ascencio, Pedro. "Adaptive observer design for parabolic partial differential equations." Thesis, Imperial College London, 2017. http://hdl.handle.net/10044/1/49454.
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This thesis addresses the observer design problem, for a class of linear one-dimensional parabolic Partial Differential Equations, considering the simultaneous estimation of states and parameters from boundary measurements. The design is based on the Backstepping methodology for Partial Differential Equations and extends its central idea, the Volterra transformation, to compensate for the parameters uncertainties. The design steps seek to reject time-varying parameter uncertainties setting forth a type of differential boundary value problems (Kernel-PDE/ODEs) to accomplish its objective, the solution of which is computed at every fixed sampling time and constitutes the observer gains for states and parameters. The design does not include any pre-transformation to some canonical form and/or a finite-dimensional formulation, and performs a direct parameter estimation from the original model. The observer design problem considers two cases of parameter uncertainty, at the boundary: control gain coefficient, and in-domain: diffusivity and reactivity parameters, respectively. For a Luenberger-type observer structure, the problems associated to one and two points of measurement at the boundary are studied through the application of an intuitive modification of the Volterra-type and Fredholm-type transformations. The resulting Kernel-PDE/ODEs are addressed by means of a novel methodology based on polynomial optimization and Sum-of-Squares decomposition. This approach allows recasting these coupled differential equations as convex optimization problems readily implementable resorting to semidefinite programming, with no restrictions to the spectral characteristics of some integral operators or system's coefficients. Additionally, for polynomials Kernels, uniqueness and invertibility of the Fredholm-type transformation are proved in the space of real analytic and continuous functions. The direct and inverse Kernels are approximated as the optimal polynomial solution of a Sum-of-Squares and Moment problem with theoretically arbitrary precision. Numerical simulations illustrate the effectiveness and potentialities of the methodology proposed to manage a variety of problems with different structures and objectives.
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Melvin, James E. "AUV fault detection using model based observer residuals." Thesis, Monterey, Calif. : Naval Postgraduate School, 1998. http://bosun.nps.edu/uhtbin/hyperion-image.exe/NPS-ME-98-004.pdf.
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Thesis (M.S. in Mechanical Engineering and Mechanical Engineer) Naval Postgraduate School, June 1998.Title from cover. Thesis advisor(s): Anthony J. Healey. "June 1998."--Cover. "NPS-ME-98-004"--Cover. Includes bibliographical references (p. 117-118). Also available online.
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Jenkins, Benjamin Michael. "Fast adaptive observers for battery management systems." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/111732.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2017.Cataloged from PDF version of thesis. Page 145 blank.
Includes bibliographical references (pages 139-144).
With the proliferation of batteries in transportation, mobile devices and, more recently, large scale energy storage, the demand for new efficient and safe algorithms for battery management has surged. More complex chemistry cells, such as lithium-ion batteries, with their sensitivity to mishandling, misuse and defects as is evident with recent device recalls due to fires, have historically been treated more conservatively. Maximizing performance of these cells safely requires knowledge of internal variables of interest which are not directly measurable. Therefore, accurate models which estimate these variables are needed. The focus of this thesis will be on a modified Single Particle Model (SPM), specifically its internal state estimates. Unfortunately, while the model structure is known, internal parameters which specify it are not, hence, state estimation alone is not enough. This motivates simultaneous state estimation and parameter identification of the electrochemical model. Existing solutions to this task are minimal in the literature. Hence this thesis. This thesis enumerates multiple developments in electrochemical modeling and adaptive observers in general. The first and fundamental component is a modification of the SPM with attractive features such as the encapsulation of lithium diffusion as a linear dynamical system independent of nonlinearities and decoupling of the nonlinear relationships defining the kinetic properties of lithium ion transfer and open circuit potential respectively. A second development defines a set of guidelines reducing the design parameters for adaptive observers to a single tuning parameter, enabling rapid implementation and prototyping. Third, a new variant of adaptive observer, using multiple simultaneous equivalent system representations, is derived for fast parameter convergence. A novel selection of observer design variables and augmentation of the underlying equivalent system with nonlinear basis functions constitutes a fourth development extensively validated through numerical simulation and theory. This adaptive observer combined with an independent offline algorithm to update effective electrode capacity and available lithium adapts every parameter of the modified SP model to account for aging or manufacturing differences. Validation of this observer in hardware using commercially available Panasonic 18650 cells completes the goals originally set forth for this research. The developments presented pave the way for fast, computationally efficient, advanced battery management systems with the potential to increase the effective capacity of a battery or alternatively reduce the size, and therefore cost, of batteries in various applications.
by Benjamin Michael Jenkins.
Ph. D.
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Heydari, Mahdi. "Adaptive distributed observers for a class of linear dynamical systems." Digital WPI, 2015. https://digitalcommons.wpi.edu/etd-dissertations/227.
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The problem of distributed state estimation over a sensor network in which a set of nodes collaboratively estimates the state of continuous-time linear systems is considered. Distributed estimation strategies improve estimation and robustness of the sensors to environmental obstacles and sensor failures in a sensor network. In particular, this dissertation focuses on the benefits of weight adaptation of the interconnection gains in distributed Kalman filters, distributed unknown input observers, and distributed functional observers. To this end, an adaptation strategy is proposed with the adaptive laws derived via a Lyapunov-redesign approach. The justification for the gain adaptation stems from a desire to adapt the pairwise difference of estimates as a function of their agreement, thereby enforcing an interconnection-dependent gain. In the proposed scheme, an adaptive gain for each pairwise difference of the interconnection terms is used in order to address edge-dependent differences in the estimates. Accounting for node-specific differences, a special case of the scheme is presented where it uses a single adaptive gain in each node estimate and which uniformly penalizes all pairwise differences of estimates in the interconnection term. In the case of distributed Kalman filters, the filter gains can be designed either by standard Kalman or Luenberger observers to construct the adaptive distributed Kalman filter or adaptive distributed Luenberger observer. Stability of the schemes has been shown and it is independent of the graph topology and therefore the schemes are applicable to both directed and undirected graphs. The proposed algorithms offer a significant reduction in communication costs associated with information flow by the nodes compared to other distributed Kalman filters. Finally, numerical studies are presented to illustrate the performance and effectiveness of the proposed adaptive distributed Kalman filters, adaptive distributed unknown input observers, and adaptive distributed functional observers.
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Shriba, S. "Adaptive identifier and observer algorithms for unknown order linear systems." Thesis, Brunel University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.351772.
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Ingallina, Alessandro. "Adaptive High-Gain Observers via Discete time Identifier." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
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The system's state observation is one of the most important problem in control theory, and it becomes extremely challenging when the system model is not entirely known. For linear systems the problem is solved by using Luenberger observer in a deterministic framework and by Kalman filter in a stochastic framework, while for nonlinear systems, the observation problem is still a research topic. The aim of this thesis is to give a framework, in which the adaptation problem, relative to the model unknowns, can be performed by system identification techniques. In particular, in this thesis we develop and implement adaptive observers design, that uses "universal approximator" to perform the adaptation problem. Moreover, we present simulations on the performance of the proposed observer.
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Kappus, Julia Johanna. "Nonparametric adaptive estimation for discretely observed Lévy processes." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät II, 2012. http://dx.doi.org/10.18452/16613.
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Die vorliegende Arbeit hat nichtparametrische Schätzmethoden für diskret beobachtete Lévyprozesse zum Gegenstand. Ein Lévyprozess mit endlichen zweiten Momenten und endlicher Variation auf Kompakta wird niederfrequent beobachtet. Die Sprungdynamik wird vollständig durch das endliche signierte Maß my(dx):= x ny(dx) beschrieben. Ein lineares Funktional von my soll nichtparametrisch geschätzt werden. Im ersten Teil werden Kernschätzer konstruiert und obere Schranken für das korrespondierende Risiko bewiesen. Daraus werden Konvergenzraten unter Glattheitsannahmen an das Lévymaß hergeleitet. Für Spezialfälle werden untere Schranken bewiesen und daraus Minimax-Optimalität gefolgert. Der Schwerpunkt liegt auf dem Problem der datengetriebenen Wahl des Glättungsparameters, das im zweiten Teil untersucht wird. Da die nichtparametrische Schätzung für Lévyprozesse starke strukturelle Ähnlichkeiten mit Dichtedekonvolutionsproblemen mit unbekannter Fehlerdichte aufweist, werden beide Problemstellungen parallel diskutiert und die Methoden allgemein sowohl für Lévyprozesse als auch für Dichtedekonvolution entwickelt. Es werden Methoden der Modellwahl durch Penalisierung angewandt. Während das Prinzip der Modellwahl im üblichen Fall darauf beruht, dass die Fluktuation stochastischer Terme durch Penalisierung mit einer deterministischen Größe beschränkt werden kann, ist die Varianz im hier betrachteten Fall unbekannt und der Strafterm somit stochastisch. Das Hauptaugenmerk der Arbeit liegt darauf, Strategien zum Umgang mit dem stochastischen Strafterm zu entwickeln. Dabei ist ein modifizierter Schätzer für die charakteristische Funktion im Nenner zentral, der es erlaubt, die punktweise Kontrolle der Abweichung dieses Objects von seiner Zielgröße auf die gesamte reelle Achse zu erweitern. Für die Beweistechnik sind insbesondere Talagrand-Konzentrationsungleichungen für empirische Prozesse relevant.This thesis deals with nonparametric estimation methods for discretely observed Lévy processes. A Lévy process X having finite variation on compact sets and finite second moments is observed at low frequency. The jump dynamics is fully described by the finite signed measure my(dx)=x ny(dx). The goal is to estimate, nonparametrically, some linear functional of my. In the first part, kernel estimators are constructed and upper bounds on the corresponding risk are provided. From this, rates of convergence are derived, under regularity assumptions on the Lévy measure. For particular cases, minimax lower bounds are proved. The rates of convergence are thus shown to be minimax optimal. The focus lies on the data driven choice of the smoothing parameter, which is being considered in the second part. Since nonparametric estimation methods for Lévy processes have strong structural similarities with with nonparametric density deconvolution with unknown error density, both fields are discussed in parallel and the concepts are developed in generality, for Lévy processes as well as for density deconvolution. The choice of the bandwidth is realized, using techniques of model selection via penalization. The principle of model selection via penalization usually relies on the fact that the fluctuation of certain stochastic quantities can be controlled by penalizing with a deterministic term. Contrarily to this, the variance is unknown in the setting investigated here and the penalty term is hence itself a stochastic quantity. It is the main concern of this thesis to develop strategies to dealing with the stochastic penalty term. The most important step in this direction will be a modified estimator of the unknown characteristic function in the denominator, which allows to make the pointwise control of this object uniform on the real line. The main technical tools involved in the arguments are concentration inequalities of Talagrand type for empirical processes.
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Sarkar, Samrat. "Blur adaptation with source and observer methods." Thesis, Queensland University of Technology, 2017. https://eprints.qut.edu.au/103277/1/Samrat_Sarkar_Thesis.pdf.
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Blur adaptation is the improvement of visual and perceptual performance with time following viewing of a blurred target. It is possible to generate blurred images with two different methods – source and observer methods. This study compared blur adaption with source and observer methods for combinations of defocus and higher-order aberrations. Participants adapted to a blurred natural scene for 1 minute and performed a visual acuity task with tumbling Es. Negligible blur adaption was noticed for both source and observer methods. A longer adapting period might be necessary to achieve significant improvement in visual acuity following blur adaptation.
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Sevinc, Ata. "Speed sensorless control of induction motors." Thesis, University of Bristol, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364962.
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Limoge, Damas Wilks. "Reduced-order modeling and adaptive observer design for lithium-ion battery cells." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/111722.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2017.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 167-171).
This thesis discusses the design of a control-oriented modeling approach to Lithium- Ion battery modeling, as well as the application of adaptive observers to this structure. It begins by describing the fundamental problem statement of a battery management system (BMS), and why this is challenging to solve. It continues by describing, in brief, several different modeling techniques and their use cases, then fully expounds two separate high fidelity models. The first model, the ANCF, was initiated in previous work, and has been updated with novel features, such as dynamic diffusion coefficients. The second model, the ANCF II, was developed for this thesis and updates the previous model to better solve the problems facing the construction of an adaptive observer, while maintaining its model accuracy. The results of these models are presented as well. After establishing a model with the desired accuracy and complexity, foundational observers are designed to estimate the states and parameters of the time-varying ionic concentrations in the solid electrode and electrolyte, as well as an a-priori estimate of the molar flux. For the solid electrode, it is shown that a regressor matrix can be constructed for the observer using both spatial and temporal filters, limiting the amount of additional computation required for this purpose. For the molar flux estimate, it is shown that fast convergence is possible with coefficients pertaining to measurable inputs and outputs, and filters thereof. Finally, for the electrolyte observer, a novel structure is established to restrict learning only along unknown degrees of freedom of the model system, using a Jacobian steepest descent approach. Following the results of these observers, an outline is sketched for the application of a machine learning algorithm to estimate the nonlinear effects of cell dynamics.
by Damas Wilks Limoge.
S.M.
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Watechagit, Sarawoot. "Modeling and estimation for stepped automatic transmission with clutch-to-clutch shift technology." Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1087316345.
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Thesis (Ph. D.)--Ohio State University, 2004.Title from first page of PDF file. Document formatted into pages; contains xxvi, 286 p. : ill. (some col.). Advisor: Krishnaswamy Srinivasan, Department of Mechanical Engineering. Includes bibliographical references (p. 280-286).
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Johnson, Clifford Edgar. "Adaptive control of combution instabilities using real-time modes observation." Diss., Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-03232006-223052/.
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Thesis (Ph. D.)--Mechanical Engineering, Georgia Institute of Technology, 2006.Zinn, Ben, Committee Chair ; Glezer, Ari, Committee Member ; Shelton, Samuel, Committee Member ; Lieuwen, Tim, Committee Member ; Neumeier, Yedidia, Committee Member.
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Boizot, Nicolas. "Adaptative high-gain extended Kalman filter and applications." Phd thesis, Université de Bourgogne, 2010. http://tel.archives-ouvertes.fr/tel-00559107.
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The work concerns the "observability problem"--the reconstruction of a dynamic process's full state from a partially measured state-- for nonlinear dynamic systems. The Extended Kalman Filter (EKF) is a widely-used observer for such nonlinear systems. However it suffers from a lack of theoretical justifications and displays poor performance when the estimated state is far from the real state, e.g. due to large perturbations, a poor initial state estimate, etc. . . We propose a solution to these problems, the Adaptive High-Gain (EKF). Observability theory reveals the existence of special representations characterizing nonlinear systems having the observability property. Such representations are called observability normal forms. A EKF variant based on the usage of a single scalar parameter, combined with an observability normal form, leads to an observer, the High-Gain EKF, with improved performance when the estimated state is far from the actual state. Its convergence for any initial estimated state is proven. Unfortunately, and contrary to the EKF, this latter observer is very sensitive to measurement noise. Our observer combines the behaviors of the EKF and of the high-gain EKF. Our aim is to take advantage of both efficiency with respect to noise smoothing and reactivity to large estimation errors. In order to achieve this, the parameter that is the heart of the high-gain technique is made adaptive. Voila, the Adaptive High-Gain EKF. A measure of the quality of the estimation is needed in order to drive the adaptation. We propose such an index and prove the relevance of its usage. We provide a proof of convergence for the resulting observer, and the final algorithm is demonstrated via both simulations and a real-time implementation. Finally, extensions to multiple output and to continuous-discrete systems are given.
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Warsewa, Alexander [Verfasser]. "Energy-based modeling and decentralized observers for adaptive structures / Alexander Warsewa." Düren : Shaker, 2021. http://d-nb.info/1238497411/34.
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Yaacob, Zulkipli Bin. "Feedback control of uncertain systems : observers, dynamic compensators and adaptive stabilization." Thesis, University of Bath, 1989. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234634.
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Li, Jingchuan. "Adaptive sliding mode observer and loss minimization for sensorless field orientation control of induction machine." Columbus, Ohio : Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1132428071.
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Wragge-Morley, Robert. "Parameter estimation in road vehicles using non-linear adaptive observer and novel data fusion techniques." Thesis, University of Bristol, 2017. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.715766.
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Yang, Bo. "Perturbation observer based adaptive passive control and applications for VSC-HVDC systems and FACTS devices." Thesis, University of Liverpool, 2015. http://livrepository.liverpool.ac.uk/2034842/.
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The technology of voltage source converter based high voltage direct current (VSC-HVDC) system and devices used in flexible AC transmission systems (FACTS) has evolved significantly over the past two decades. It is used to effectively enhance power system stability. One of the important issues is how to design an applicable nonlinear adaptive controller for these devices to effectively handle the system nonlinearities and uncertainties. Passive control (PC) has been proposed for the control of nonlinear systems based on Lyapunov theory, which has the potential to improve the system damping as the beneficial system nonlinearities are remained instead of being fully cancelled. However, PC is not applicable in practice as it requires an accurate system model. Adaptive passive control (APC) and robust passive control (RPC) have been developed to handle some specific type of system uncertainties based on strict assumptions on system structure and uncertainty. However, their applications are limited as various system uncertainties exist. This thesis aims to develop a perturbation observer based adaptive passive control (POAPC) to make PC applicable in practice. The combinatorial effect of system nonlinearities, parameter uncertainties, unmodelled dynamics and time-varying external disturbances is aggregated into a perturbation, which is estimated by a perturbation observer (PO). The proposed approach does not require an accurate system model and can handle various system uncertainties. POAPC is applied to two-terminal VSC-HVDC systems to handle various system uncertainties. The VSC-HVDC system model is firstly developed, the proposed controller can inject an extra system damping and only the measurement of direct current (DC) voltage, active and reactive power is needed. The effectiveness ofPOAPC is verified by simulation in comparison with that of passive control (PC) and proportional-integral (PI) control. Moreover, a hardware experiment is carried out to verify its implementation feasibility and applicability. A passive controller is designed for multi-terminal VSC-HVDC (VSC-MTDC) systems via energy shaping, in which the dynamics related to the active power, reactive power, and DC cable voltage is transformed into an output strictly passive form. Then the remained internal dynamics related to DC cable current and common DC voltage is proved to be asymptotically stable in the context of Lyapunov criterion. PC is applied on a four-terminal VSC-MTDC system under eight cases to evaluate its control performance. POAPC is developed on the VSC-MTDC system to maintain a consistent control performance under different operating points and provide a significant robustness to parameter uncertainties, together with other unmodelled dynamics and time-varying external disturbances. Simulation results are provided to evaluate the control performance of POAPC in comparison to that of PI control and PC. Perturbation observer based coordinated adaptive passive control (POCAPC) is proposed for excitation controller (EC) and FACTS controller on both single machine infinite bus (SMIB) systems and multi-machine power systems. Only the range of control Lyapunov function (CLF) is needed and the dependence of an accurate system model can be partially reduced, thus POCAPC can be easily applied to multi-machine power systems. Its control performance is compared with that of conventional proportional-integral-derivative and lead-lag (PID+LL) control, coordinated passive control (CPC) and coordinated adaptive passive control (CAPC) on both an SMIB system and a three-machine power system by simulation. Then a hardware-in-the-loop (HIL) test is undertaken to verify the implementation feasibility of the proposed controller.
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TRUMIC, Maja. "STIFFNESS ESTIMATION AND ADAPTIVE CONTROL FOR SOFT ROBOTS." Doctoral thesis, Università degli Studi di Palermo, 2021. http://hdl.handle.net/10447/509120.
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Nonostante la sorprendente crescita nello sviluppo dei robot ispirati alla natura, tra cui i cosiddetti soft robot, il potenziale di questi sistemi, che hanno intrinseche capacità di adattamento, non è ancora stato sfruttato a pieno. La ricerca ha principalmente considerato il controllo in retroazione della posizione dei giunti del robot, lasciando la gestione della cedevolezza di questi ultimi ancora in anello aperto. Peraltro, le attuali limitazioni nel processo di produzione degli attuatori a cedevolezza variabile e l'inevitabile variabilità nel tempo degli elementi elastici costitutivi, i quali sono soggetti ad usura e deformazione plastica, rendono il problema della determinazione precisa della rigidezza di giunto ancora oggi una sfida.
In tale ambito, questa tesi pone l'accento sulla stima della rigidezza e sul controllo adattativo dei soft robot, considerando in primis i sistemi articolati e pilotati da attuatori a cedevolezza variabile (VSA) in configurazione antagonista. Ciò viene fatto con l'obiettivo primario di imporre simultaneamente una dinamica desiderata sia per la posizione che per la rigidezza e, conseguentemente, di migliorare la sicurezza fisica e le prestazioni di un soft robot.
Basandosi sulla teoria degli osservatori ad ingresso sconosciuto (UIO), in questo lavoro vengono proposte soluzioni, invasive e non, che consentono di stimare la rigidezza nei robot con attuatori pneumatici o elettromeccanici, soluzioni che nel secondo caso vengono anche validate sperimentalmente. Oltre al vantaggio della linearità e della scalabilità, le suddette soluzioni hanno l'interessante caratteristica di non richiedere l'uso di sensori di coppia o velocità.
Sfruttando così la disponibilità di una stima della rigidezza, il lavoro descrive inoltre dei metodi innovativi per il controllo robusto dei soft robot articolati, il cui schema include un compensatore adattativo e un disaccoppiatore dinamico. Detti metodi possono gestire le incertezze nella conoscenza del modello dinamico del robot e, quando il riferimento della rigidezza è costante o lentamente variabile, anche quelle relative all'attuatore pneumatico. La loro verifica è valutata attraverso delle simulazioni e, nel caso pneumatico, anche per via sperimentale.
Infine, la tesi mostra come estendere le tecniche di controllo adattativo ai sistemi robotici con cedevolezza distribuita lungo l'intero corpo del robot, garantendo formalmente la convergenza del controllore. L'efficacia di questa tecnica adattativa è mostrata attraverso una estensiva simulazione.Although there has been an astonishing increase in the development of nature-inspired robots equipped with compliant features, i.e. soft robots, their full potential has not been exploited yet. One aspect is that the soft robotics research has mainly focused on their position control only, while stiffness is managed in open loop. Moreover, due to the difficulties of achieving consistent production of the actuation systems for soft articulated robots and the time-varying nature of their internal flexible elements, which are subject to plastic deformation over time, it is currently a challenge to precisely determine the joint stiffness. In this regard, the thesis puts an emphasis on stiffness estimation and adaptive control for soft articulated robots driven by antagonistic Variable Stiffness Actuators (VSAs) with the aim to impose the desired dynamics of both position and stiffness, which would finally contribute to the overall safety and improved performance of a soft robot. By building upon Unknown Input Observer (UIO) theory, invasive and non-invasive solutions for estimation of stiffness in pneumatic and electro-mechanical actuators are proposed and in the latter case also experimentally validated. Beyond the linearity and scalability advantage, the approaches have an appealing feature that torque and velocity sensors are not needed. Once the stiffness is determined, innovative control approaches are introduced for soft articulated robots comprising an adaptive compensator and a dynamic decoupler. The solutions are able to cope with uncertainties of the robot dynamic model and, when the desired stiffness is constant or slowly-varying, also of the pneumatic actuator. Their verification is performed via simulations and then the pneumatic one is successfully tested on an experimental setup. Finally, the thesis shows via extensive simulations the effectiveness of adaptive technique applied to soft-bodied robots, previously deriving the sufficient and necessary conditions for the controller convergence.
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Lei, Hao. "Universal Output Feedback Control of Nonlinear Systems." Case Western Reserve University School of Graduate Studies / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=case1193422144.
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Jin, Yufang. "NONLINEAR ADAPTIVE ESTIMATION ANDITS APPLICATION TO SYNCHRONIZATION OF LORENZ SYSTEM." Doctoral diss., University of Central Florida, 2004. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4460.
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Synchronization and estimation of unknown constant parameters for Lorenz-type transmitter are studied under the assumption that one of the three state variables is not transmitted and that transmitter parameters are not known apriori. An adaptive algorithm is proposed to estimate both the state and system parameters. Since Lorenz system shows the property of sensitivity to initial conditions and evolves in different mode with parameter variation, an equivalent system is introduced. The adaptive observer is designed based on this equivalent system without any requirement on initial conditions of the observer. It is shown by Lyapunov arguments and persistent excitation analysis that exponential stability of state and parameter estimation is guaranteed. Simulation results are included to demonstrate properties of the algorithm. In a practical communication system,the received signals presented at the receiver part differ from those which were transmitted due to the effects of noise. The proposed synchronization scheme is robust with regard to external bounded disturbance. When an additive white gaussian noise (AWGN) channel model is considered, estimates of state and parameter converge except for small errors. The results show promise in either coherent detection or the message decoding intelecommunication systems.Ph.D.
Department of Electrical and Computer Engineering
Engineering and Computer Science
Electrical and Computer Engineering
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Al-Durra, Ahmed Abad. "MODEL-BASED ESTIMATION FOR IN-CYLINDER PRESSURE OF ADVANCED COMBUSTION ENGINES." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1281715345.
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Warsewa, Alexander [Verfasser], and Cristina [Akademischer Betreuer] Tarín. "Energy-based modeling and decentralized observers for adaptive structures / Alexander Warsewa ; Betreuer: Cristina Tarín." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2021. http://d-nb.info/1239116071/34.
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Anisi, David A. "Online trajectory planning and observer based control." Licentiate thesis, Stockholm : Optimization and systems theory, Royal Institute of Technology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4153.
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Afri, Chouaib. "Observateurs adaptatifs pour l'identification en ligne et l'observation des systèmes linéaires." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1302/document.
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Dans cette thèse, nous étudions le problème de l'identification d'un système à dynamique linéaire. Dans un premier temps, nous répertorions les différentes méthodes qui ont été développées dans la littérature en nous concentrant plus particulièrement sur les méthodes des observateurs adaptatifs. Dans un second temps nous présentons un premier algorithme qui est une approche mixant les méthodes des sous-espaces et celles des observateurs adaptatifs. Ce nouvel algorithme est d'autant plus intéressant qu'il nous permet d'identifier des réalisations de systèmes MIMO dans une base d'état arbitraire. La convergence de cet algorithme est démontrée en utilisant les notions d'excitation persistantes. Dans un troisième chapitre nous introduisons une nouvelle méthode qui s'appuie sur le concept des observateurs de Luenberger non linéaires développés ces dernières années. Ce nouvel algorithme se différencie des algorithmes existants par sa capacité à produire une estimation simultanée des paramètres et de l'état du système. Nous démontrons alors sa robustesse à des perturbations affectant la dynamique interne ou les mesures. La convergence de cet algorithme est obtenue si les entrées du système satisfont une hypothèse d'excitation différentielle. Tous ces algorithmes sont alors évalués et implémentés sur un banc d'expérimentationIn this thesis, we study the problem of identification of a linear dynamical system. First, we survey various methods that have been developed in the literature. We focus more particularly on methods named adaptive observers. Secondly we present an approach which combines subspace identification methods and adaptive observers. This new method is interesting since it allows us to identify MIMO systems in an arbitrary basis. The convergence of this algorithm is demonstrated using the persistent excitation notions. In the third chapter we introduce a new method that is inspired from nonlinear Luenberger observers developed in recent years. This new algorithm is different from the existing algorithms since the parameters and the systemstatus are estimated simultaneously. We demonstrate the robustness of this approach. The convergence of the algorithm is obtained if the system inputs satisfy a differential excitation hypothesis. All these algorithms are evaluated and implemented on an experimental bench
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TRUMIC, Maja. "Stiffness Estimation and Adaptive Control for Soft Robots." Doctoral thesis, Università degli Studi di Palermo, 2021. http://hdl.handle.net/10447/479659.
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Delaunay, Tiphaine. "Adaptative observers for wave equations and associated discretizations : formulations and analysis." Electronic Thesis or Diss., Institut polytechnique de Paris, 2023. http://www.theses.fr/2023IPPAX120.
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Le contexte de cette thèse est l'étude de problèmes inverses pour les phénomènes de propagation d'onde sous l'angle de la théorie du contrôle, plus précisément la théorie de l'observation. Notre objectif est de formaliser, d'analyser et de discrétiser des stratégies appelées séquentielles en assimilation de données, où les observations sont prises en compte à mesure qu'elles sont disponibles. Le système résultant appelé observateur (ou estimateur séquentiel) se stabilise sur la trajectoire observée reconstruisant alors l'état et éventuellement des paramètres inconnus du système. Ici nous nous concentrons plus particulièrement sur la reconstruction de source au second membre d'une équation des ondes, un problème d'estimation qui peut apparaître comme intermédiaire en compléxité entre l'estimation d'état (ou de condition initiale) et l'identification de paramètres généraux. Dans ce cadre, nous proposons de définir dans un formalisme déterministe en dimension infinie, un estimateur dit de Kalman qui estime séquentiellement le terme source à identifier. Par les outils de programmation dynamique, nous montrons que cet estimateur séquentiel est équivalent à la minimisation d'une fonctionnelle, cette équivalence nous permettant d'en proposer l'analyse de convergence sous condition d'observabilité. Nous démontrons alors des inégalités d'observabilité pour différents types de source en combinant analyse fonctionnelle, méthodes des multiplicateurs et estimations de Carleman. Ces inégalités nous informent notamment sur le caractère éventuellement mal-posé des problèmes inverses de reconstruction que nous étudions et nous permettent d'en quantifier le degré et ainsi d'adapter les régularisation proposées. Nous comparons notamment des stratégies inverser-et-régulariser par opposition à regulariser-pour-inverser. Concernant les questions de discrétisation et leur analyse numérique, nous défendons l'idée de redéfinir ces observateurs associés à la minimisation de la fonctionnelle une fois que le modèle direct a été discrétisé. Cette approche discrétiser-puis-optimiser est avantageuse pour l'analyse par rapport à optimiser-puis-discrétiser. Il n'en reste pas moins que les inégalités d'observabilité doivent être étendues aux systèmes discrets. À ce propos, nous étendons en particulier des résultats de stabilisation exponentielle uniforme en la discrétisation pour des discrétisations par éléments finis de haut degré de l'équation des ondesThe context of this thesis is the study of inverse problems for wave propagation phenomena from a control theory perspective, more specifically using observation theory. Our goal is to formalize, analyze, and discretize strategies called sequential in data assimilation, where measurements are taken into account as they become available. The resulting system, called an observer (or a sequential estimator), stabilizes on the observed trajectory hence reconstructs the state and possibly some unknown parameters of the system. Here we focus in particular on source reconstruction on the right-hand side of our wave equation, an estimation problem intermediate in complexity between state estimation (or initial condition estimation) and the more general problem of parameter identification. In this context, we propose to define in a deterministic framework in infinite dimension a so-called Kalman estimator that sequentially estimates the source term to be identified. Using dynamic programming tools, we show that this sequential estimator is equivalent to the minimization of a functional. This equivalence allows us to propose convergence analysis under observability conditions. We then demonstrate observability inequalities for different source types by combining functional analysis, multiplier methods, and Carleman estimates. In particular, these inequalities inform us about the ill-poseness nature of the inverse reconstruction problems we study and allow us to quantify the degree of ill-posedness hence to propose adapted regularizations. In particular, we compare an invert-and-regularize strategies as opposed to regularize-to-invert. Concerning discretization issues and their analysis, we defend the idea of redefining these observers associated with the minimization of the functional once the direct model has been discretized. This discretize-then-optimize approach is advantageous for the analysis compared to optimize-then-discretize approach. Nevertheless, the observability inequalities need to be extended to discretized systems. In particular, in this context, we extend uniform exponential stabilization results to the discretization for high-order finite element discretizations of the wave equation
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Ton, That Long. "Nonlinear control studies for circadian models in system biology." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/nonlinear-control-studies-for-circadian-models-in-system-biology(f616f360-99e4-4314-ba51-be7a49e9ff0e).html.
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Circadian rhythms exist in almost all of living species, and they occupy an important role in daily biological activities of these species. This thesis deals with reduction of measurements in circadian models, and recovery of circadian phases. Two mathematical models of circadian rhythms are considered, with a 3rd order model for Neurospora, and a 7th order model for Mammals. The reduction of measurements of circadian models is shown by the proposals of observer designs to the two mathematical models of circadian rhythms. Both mathematical models contain strong nonlinearities, which make the observer design challenging. Two observer designs, reduced-order and one-sided Lipschitz, are applied to the circadian models to tackle the nonlinearities. Reduced-order observer design is based on a state transformation to make certain nonlinearities have no impact on the observer errors, and the design of one-sided Lipschitz observer is based on systems with one-sided Lipschitz nonlinearities. Both observer designs are based on the existing methods in literature. The existing method of reduced-order observer has been applied to a class of multi-output nonlinear systems. A new reduced-order observer design which extends the existing one in literature is presented in this thesis. In this new reduced-order observer method, the observer error dynamics can be designed by choosing the observer gain, unlike the existing one, of which the observer error dynamics depend on the invariant zeros under certain input-output map. The recovery of circadian phases is carried out to provide a solution to phase shifts occurred in circadian disorders. The restoration of circadian phases is performed by the synchronizations of trajectories of a controlled model with trajectories of a reference model. The reference model and the controlled model have phase differences, and both these models are based on a given 3rd order model of Neurospora circadian rhythms. The phase differences are reflected by different initial conditions, and by parameter uncertainty. The synchronizations of the two models are performed by using back-stepping method for the case of different initial conditions, and by using adaptive back-stepping method for the remaining case. Several simulation studies of the proposed observer designs and the proposed schemes of synchronizations are carried out with the results shown in this thesis.
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Ouddah, Nadir. "Commande robuste de machines à réluctance variable pour la traction de véhicules électriques." Thesis, Cergy-Pontoise, 2015. http://www.theses.fr/2015CERG0789.
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Le moteur à réluctance variable (MRV) est en train de gagner beaucoup d'intérêt dans les applications de traction électrique grâce à la compatibilité significative entre ses caractéristiques naturelles et les exigences de l'industrie automobile. Cependant, à cause de la caractéristique fortement non linéaire des grandeurs électromagnétiques du MRV, l'usure du moteur, les variations paramétriques dues aux tolérances de fabrication, et la dérive des paramètres durant le fonctionnement, les stratégies de commande classique ne permettent pas d'assurer des hautes performances de suivi de trajectoire et de robustesse en stabilité dans l'environnement de fonctionnement d'un véhicule électrique. Dans ce contexte, le premier objectif de cette thèse est de proposer des stratégies de commande robustes du MRV en prenant en considération les contraintes imposées par les applications de traction. Afin d'atteindre cet objectif, une structure de commande en cascade, composée d'une boucle externe de vitesse et d'une boucle interne de courant, est envisagée. Les objectifs de synthèse sont ensuite fixés à travers un cahier des charges formulé en termes de gabarits fréquentiels, et les correcteurs robustes et adaptatifs de vitesse et de courant sont ainsi synthétisés en se basant sur les approches de commande H-infini et LPV/H- infini. La faisabilité des correcteurs constitue également un critère important dans les applications de traction électrique où la puissance de calcul embarqué dans le véhicule est très limitée. Ce critère est pris en considération dans cette thèse à travers l'utilisation des approches de synthèse des correcteurs H- infini d'ordre fixe. Les performances de ces correcteurs sont analysées et comparées avec les performances des correcteurs H- infini classiques à travers une étude par la μ-analyse de la robustesse en stabilité et une évaluation expérimentale. Le deuxième objectif de ces travaux de thèse est d'évaluer l'intérêt de la commande sans capteurs mécanique du MRV en se basant sur des méthodes d'estimation. Des observateurs robustes basés sur les modes glissants et le filtrage de Kalman sont ainsi synthétisés. Les performances et la robustesse de ces observateurs sont ensuite comparées expérimentalement dans une perspective d'une application de traction électriqueThe switched reluctance motor (SRM) is gaining much interest in electric vehicle applications. It includes robustness to harsh operational conditions, rugged structure, fault tolerant operation and a wide range of speed. However, due to the highly nonlinear electromagnetic characteristic, wear and tear of motor, manufacturing tolerances and parameters drift during operation, classical control strategies do not ensure high dynamical performance and robustness under various operating conditions in electric vehicle environment. In this context, the first purpose of this thesis is to propose robust control strategies of the SRM taking into account the constraints imposed by electric vehicle applications. To achieve this objective, a cascade control scheme is adopted; it consists of an outer speed loop and an inner current loop. Controllers design aims are fixed through specifications formulated in frequency domain, robust and adaptive controllers of speed and currents are thus synthesized based on H- infini and LPV/H- infini control approaches. Feasibility of these controllers is also an important criterion in electric vehicles applications where embedded computing power is very limited. This criterion is taken into account in this thesis by using fixed order controller synthesis approaches. The performances of these controllers are analyzed and compared with the performances of standard H- infini controllers through an experimental evaluation and a robustness analysis is performed using the concept of the Singular Structured Value, i.e. the μ-analysis. The second objective of this thesis is to assess the interest of the sensorless control of SRM. Robust observers based on second order sliding mode (SMO2) and Kalman filtering techniques (EKF) are designed to estimate the mechanical states of SRM. Performances and robustness of these observers are then compared experimentally in perspective of electric vehicle application
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Huang, Yanan. "Active Control and Adaptive Estimation of an Optically Trapped Probing System." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1250617605.
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Kappus, Julia Johanna [Verfasser], Markus [Akademischer Betreuer] Reiß, Michael [Akademischer Betreuer] Neumann, and Fabienne [Akademischer Betreuer] Comte. "Nonparametric adaptive estimation for discretely observed Lévy processes / Julia Johanna Kappus. Gutachter: Markus Reiß ; Michael Neumann ; Fabienne Comte." Berlin : Humboldt Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät II, 2012. http://d-nb.info/1028566778/34.
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Anisi, David A. "On Cooperative Surveillance, Online Trajectory Planning and Observer Based Control." Doctoral thesis, KTH, Optimeringslära och systemteori, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-9990.
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The main body of this thesis consists of six appended papers. In the first two, different cooperative surveillance problems are considered. The second two consider different aspects of the trajectory planning problem, while the last two deal with observer design for mobile robotic and Euler-Lagrange systems respectively.In Papers A and B, a combinatorial optimization based framework to cooperative surveillance missions using multiple Unmanned Ground Vehicles (UGVs) is proposed. In particular, Paper A considers the the Minimum Time UGV Surveillance Problem (MTUSP) while Paper B treats the Connectivity Constrained UGV Surveillance Problem (CUSP). The minimum time formulation is the following. Given a set of surveillance UGVs and a polyhedral area, find waypoint-paths for all UGVs such that every point of the area is visible from a point on a waypoint-path and such that the time for executing the search in parallel is minimized. The connectivity constrained formulation extends the MTUSP by additionally requiring the induced information graph to be kept recurrently connected at the time instants when the UGVs perform the surveillance mission. In these two papers, the NP-hardness of both these problems are shown and decomposition techniques are proposed that allow us to find an approximative solution efficiently in an algorithmic manner.Paper C addresses the problem of designing a real time, high performance trajectory planner for an aerial vehicle that uses information about terrain and enemy threats, to fly low and avoid radar exposure on the way to a given target. The high-level framework augments Receding Horizon Control (RHC) with a graph based terminal cost that captures the global characteristics of the environment. An important issue with RHC is to make sure that the greedy, short term optimization does not lead to long term problems, which in our case boils down to two things: not getting into situations where a collision is unavoidable, and making sure that the destination is actually reached. Hence, the main contribution of this paper is to present a trajectory planner with provable safety and task completion properties. Direct methods for trajectory optimization are traditionally based on a priori temporal discretization and collocation methods. In Paper D, the problem of adaptive node distribution is formulated as a constrained optimization problem, which is to be included in the underlying nonlinear mathematical programming problem. The benefits of utilizing the suggested method for online trajectory optimization are illustrated by a missile guidance example.In Paper E, the problem of active observer design for an important class of non-uniformly observable systems, namely mobile robotic systems, is considered. The set of feasible configurations and the set of output flow equivalent states are defined. It is shown that the inter-relation between these two sets may serve as the basis for design of active observers. The proposed observer design methodology is illustrated by considering a unicycle robot model, equipped with a set of range-measuring sensors. Finally, in Paper F, a geometrically intrinsic observer for Euler-Lagrange systems is defined and analyzed. This observer is a generalization of the observer proposed by Aghannan and Rouchon. Their contractivity result is reproduced and complemented by a proof that the region of contraction is infinitely thin. Moreover, assuming a priori bounds on the velocities, convergence of the observer is shown by means of Lyapunov's direct method in the case of configuration manifolds with constant curvature.QC 20100622
TAIS, AURES
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Liu, Jianxing. "Contributions to Adaptative Higher Order Sliding Mode Observers : Application to Fuel Cell an Power Converters." Thesis, Belfort-Montbéliard, 2014. http://www.theses.fr/2014BELF0232/document.
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Les systèmes piles à combustible de type PEM pour des applications de transport reposent sur un ensemble d’auxiliaires (stockage d’hydrogène, compresseur d’air, convertisseur de puissance, humidificateur, etc) qui assurent le bon fonctionnement du système pile. La mise en place d’observateurs permet de disposer d’un outil pour reconstruire les états non mesurés de ce système; cela permet de mettre en place un contrôle par retour de sortie en vue d’optimiser les performances du système pile et ainsi d'améliorer la détection et l’isolation de défauts (FDI). Cette thèse est basée sur l’étude et la synthèse d'observateurs adaptatifs par mode glissant d’ordre supérieur, pour deux principaux auxiliaires de la pile que sont, le système d'alimentation en air et les convertisseurs de puissance associés à la pile. La première partie de la thèse est consacrée à la synthèse d’observateurs pour la reconstruction des états et à la détection et l’isolation des défauts sur le système d’alimentation en air de la PEMFC. Dans un premier temps, un observateur algébrique par mode glissant d’ordre supérieur est synthétisé pour la reconstruction de la pression partielle de l'oxygène et de l'azote. Dans un deuxième temps, un nouvel observateur adaptatif par mode glissant d’ordre deux est synthétisé pour assurer l'observation simultanée des états, l'identification des paramètres, la surveillance et la reconstruction de défaut dans le circuit d’air. Les performances des observateurs proposées ont été validées grâce à un simulateur Hardware-In-Loop (HIL) du système pile à combustible.Dans la deuxième partie, nous nous sommes intéressés à l’élaboration d’observateurs et de commande par retour de sortie pour les convertisseurs associé au système pile dans une application transport. Ainsi, une commande novatrice par mode glissant d’ordre deux, de type retour de sortie, a été élaborée pour le convertisseur AC/DC. Dans un second temps, un observateur de type modes glissants d’ordre 2 adaptatif est synthétisé pour un convertisseur de type multicellulaireAutomotive PEM Fuel Cell systems rely upon a set of auxiliary systems for proper operation, such as humidifier, air-feed compressor, power converter etc. The internal physical states of the latter are often unmeasurable, yet required for their precise control. Observers provide a means of obtaining the unmeasured states of these auxiliary systems for feedback control, optimal energy consumption and Fault Diagnosis and Isolation (FDI). This thesis is based on higher order sliding mode observer design studies for two major PEMFC auxiliary systems found in modern automobiles, the air-feed system and the power electronics system.The first part is focused on robust observation and FDI of the PEMFC air-feed systems. Sliding mode observer design and their applications to FDI have been studied in detail for this purpose and the key observation problems in this system have been identified. Based on this study, two solutions are proposed, a sliding mode algebraic observer for oxygen and nitrogen partial pressures and a novel robust adaptive-gain Second Order Sliding Mode (SOSM) observer based FDI for simultaneous state observation, parameter identification, health monitoring and fault reconstruction of the PEMFC air-feed system. The performance of the proposed observers has been validated on an instrumented Hardware-In-Loop (HIL) test bench.The observation and output feedback control problems of different power electronic converters, commonly found in fuel cell vehicles, are addressed in the next part. Robust output feedback SOSM control for three phase AC/DC converters have been presented. A robust SOSM observer for multi-cell converters has also been designed. The performance of all these designs has been demonstrated through a multi-rate simulation approach. The results highlight the robustness of the observers and controllers against parametric uncertainty, measurement noise and external disturbance
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Gouy, Magali. "Behavioural adaption of drivers of unequipped vehicles to short time headways observed in a vehicle platoon." Thesis, Open University, 2013. http://oro.open.ac.uk/40335/.
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Advanced driver assistance systems (ADAS) are increasingly present within modern vehicles, supporting the introduction of semi- and fully-automated driving situations. As a consequence, a mixed traffic situation is likely to emerge where vehicles equipped with different degrees of automated systems will interact with unequipped vehicle drivers (UVDs). Platoons of vehicles comprise a vision for future traffic and are designed to maintain small headways in order to have a beneficial effect on both energy consumption and traffic flow. The overarching aim of this work was to investigate whether the presence of automated vehicle platoons will impact UVDs’ car-following behaviour. This required understanding in which conditions behavioural adaptation of UVDs can possibly emerge. Therefore, four studies were conducted using a car simulator whereby participants drove behind a lead vehicle in the vicinity of automated platoons of vehicles exhibiting different headway characteristics. Further external factors were varied across the different simulator studies. In summary, when drivers were motivated by instructions and not impeded by keeping track of a lead vehicle, expected changes in behaviour were noticed: reductions in mean THW, minimum THW, amount of time spent below a critical THW and the variation of lane position were observed when driving next to a platoon with short THWs. Contrarily, there was no significant effect of platoons’ headway when UVDs followed a lead vehicle as a result of congested traffic. It was interpreted that elements of the environment as well as driver’s cognitive state such as workload and motivation influenced the magnitude of the effects. Other factors are still unclear such as the influence of drivers’ personality and driving skills. More work is needed to understand fully the conditions that promote behavioural change. Beyond the scope presented here, further research is also needed to understand how increasing deployment of vehicles equipped with ADAS may affect driver behaviour across the wider vehicle fleet.
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Morel, Yannick. "Applied Nonlinear Control of Unmanned Vehicles with Uncertain Dynamics." Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/27426.
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The presented research concerns the control of unmanned vehicles. The results introduced
in this dissertation provide a solid control framework for a wide class of nonlinear uncertain
systems, with a special emphasis on issues related to implementation, such as control input
amplitude and rate saturation, or partial state measurements availability. More specifically,
an adaptive control framework, allowing to enforce amplitude and rate saturation of the
command, is developed. The motion control component of this framework, which works in
conjunction with a saturation algorithm, is then specialized to different types of vehicles.
Vertical take-off and landing aerial vehicles and a general class of autonomous marine vehicles
are considered. A nonlinear control algorithm addressing the tracking problem for a
class of underactuated, non-minimum phase marine vehicles is then introduced. This motion
controller is extended, using direct and indirect adaptive techniques, to handle parametric
uncertainties in the system model. Numerical simulations are used to illustrate the efficacy
of the algorithms. Next, the output feedback control problem is treated, for a large class of
nonlinear and uncertain systems. The proposed solution relies on a novel nonlinear observer
which uses output measurements and partial knowledge of the systemâ s dynamics to reconstruct
the entire state for a wide class of nonlinear systems. The observer is then extended
to operate in conjunction with a full state feedback control law and solve both the output
feedback control problem and the state observation problem simultaneously. The resulting
output feedback control algorithm is then adjusted to provide a high level of robustness to
both parametric and structural model uncertainties. Finally, in a natural extension of these
results from motion control of a single system to collaborative control of a group of vehicles,
a cooperative control framework addressing limited communication issues is introduced.Ph. D.
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Bonargent, Tristan. "Contributions à l'estimation de l'attitude et à la détection de l'hypovigilance au volant." Thesis, Normandie, 2020. http://www.theses.fr/2020NORMC212.
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Cette thèse porte sur l'estimation de l'attitude de corps rigides et sur la détection de l'hypovigilance au volant. Lorsque l'on cherche à estimer l'attitude, plusieurs problèmes pratiques peuvent se poser. Une première problématique concerne l'estimation de l'attitude lorsque le corps est soumis à une accélération externe non-négligeable. Nous proposons, dans ce contexte, des observateurs permettant d'estimer l'attitude de l'objet considéré tout en limitant les effets de l'accélération externe sur la qualité de l'estimation. Nous nous sommes également intéressés à un autre problème pratique : le biais du gyromètre. En effet, la structure des gyromètres peut entraîner un biais dans les mesures. Ce biais peut être assimilé à un paramètre inconnu, et doit être estimé. Pour cela, nous avons synthétisé un observateur adaptatif pour une classe de systèmes non-linéaires incertains avec des sorties multi-échantillonnées. Ces sorties, correspondant à plusieurs capteurs, peuvent être échantillonnées de façon irrégulière et indépendamment les unes des autres. L'observateur proposé a été en particulier appliqué au problème de l'estimation simultané de l'attitude et du biais. Cette thèse porte également sur la détection de l'hypovigilance au volant qui est un des nombreux domaines d'application de l'estimation de l'attitude. Nous avons montré que le niveau de vigilance d'un conducteur peut être estimé à partir de données non-intrusives. Cette problématique a été soulevée afin de pouvoir conceptualiser un dispositif fiable et non-intrusif de détection de l'hypovigilanceThis thesis focuses on the estimation of the attitude of rigid bodies and on the detection of driver drowsiness. When estimating attitude, several practical problems may arise. A first problem concerns the estimation of attitude when the body is subject to a non-negligible external acceleration. We propose, in this context, observers that estimate the attitude of the considered object while limiting the effects of the external acceleration on the quality of the estimate. We have also addressed another practical problem: the gyroscope bias. Indeed, the structure of gyroscopes can lead to a bias in the measurements. This bias can be assimilated to an unknown parameter and must be estimated. For this purpose, we have designed an adaptive observer for a class of uncertain non-linear systems with multi-sampled outputs. These outputs, corresponding to several sensors, can be sampled irregularly and independently of each other. The proposed observer has been applied in particular to the problem of simultaneous estimation of attitude and bias. This thesis also deals with the detection of driver drowsiness, which is one of the many fields of application of attitude estimation. We have shown that the driver's level of drowsiness can be estimated from non-intrusive data. This issue was raised in order to conceptualize a reliable and non-intrusive device for detecting drowsiness
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Beigzadeh, Shima. "System Dynamics and Statistical Modeling of Severe Storms: The Case of Charlottetown, P.E.I., Canada." Thesis, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/31420.
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Scientific evidence points to a changing global climate. The most vital and visible impacts of this phenomenon for sea-level communities are sea-level rise, coastal erosion, and more frequent severe coastal storms. However, limited research has been conducted to date to project the damage from rising maximum water levels and corresponding storm surges, and their impacts on the sustainability of coastal communities. This research focuses on the urban coastal community of Charlottetown, Prince Edward Island (P.E.I.), Canada as part of the C-Change International Community University research Alliance (ICURA), “Managing Adaptation to Environmental Change in Coastal Communities: Canada and the Caribbean.” The stochastic process that underlies, maximum observed water levels in Charlottetown, is modeled using historical data. Maximum observed water levels and storm surges are represented by fitted conditional and marginal univariate probability density functions. The statistical package “Easy-Fit” is used as a tool for analyzing goodness of fit to the historical data for maximum observed water levels in Charlottetown. A System Dynamics (SD) model, using STELLA, is developed to simulate the projected impacts of maximum observed water levels on the City of Charlottetown. The SD model captures the dynamics of the four pillars of community sustainability, namely Environmental, Economic, Social-Cultural and Human sectors identified for the City of Charlottetown. The model defines and evaluates the robustness of alternative adaptation strategies for various model scenarios to projected storms over a long-term planning period. The results quantify the vulnerability of Charlottetown. The analysis of the results from implementing 3 main adaptation strategies for protection, accommodation, and retreat scenarios as well as the ones from the most common current response of “doing nothing”, provide information on the dynamic and pillar-related impacts of storms on Charlottetown. Analysis of these strategy options clearly indicates that doing nothing in the face of more frequent severe storms is an inefficient strategy. Model results show that the protect strategy is unlikely to deliver complete protection, and the retreat option is costly and not well received. The accommodation strategy including a combination of protection options and controlled retreat will provide the most robust option for the coastal City of Charlottetown. The SD model and analysis provides a framework for the evaluation of adaptation strategies for alternative coastal communities.
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Ltaief, Ali. "Synthèse d'observateurs pour les systèmes non linéaires, non uniformément observables." Thesis, Normandie, 2017. http://www.theses.fr/2017NORMC211/document.
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Les résultats présentés dans cette thèse s’articulent autour de la synthèse d’observateurs de type grand gain pour des classes de systèmes non linéaires multi-entrées, multi-sorties non uniformément observables. Dans un premier temps, la classe de systèmes considérées est telle que la dynamique des variables d’état est décrite par la somme de deux termes. Le premier correspond à une partie affine en l’état décrite par le produit d’une matrice, dont les entrées (fonctions non linéaires de l’état) ont une structure triangulaire, par le vecteur d’état. Le deuxième terme est composé par les non linéarités du système qui ont aussi une structure triangulaire. Le gain de l’observateur proposé est issu de la résolution d’une équation différentielle ordinaire de type Lyapunov.La convergence exponentielle de l’erreur d’observation sous-jacente est établie sous une une certaine condition d’excitation persistante dépendant de l’entrée du système et de l’état de l’observateur.Dans un deuxième temps, la synthèse de cet observateur est étendue à une classe plus large de systèmes non linéaires où des états peuvent intervenir de manière non triangulaire.La notion d’indices caractéristiques associés à ces états est alors introduite et elle a permis de définir une structure triangulaire étendue pour la quelle la synthèse de l’observateur a aussi été effectuée.Enfin, il a été établi que les observateurs proposés peuvent être utiliséscomme observateurs adaptatifs pour l’estimation simultanée de l’état et de certains paramètres et une forme adaptative de ces observateurs a été générée.Les performances des différents observateurs proposés ont été illustrées à travers des exemples en simulationThe results given in this thesis deal with the design of high gain observers for some classes on Multi Input Multi Output non uniformly observable nonlinear systems. In a first step, the class of considered systems is such that the dynamics of the state variables is the sum of two terms. The first term is affine in the state and is composed by the product of a matrix, whose entries are nonlinear functions of the state with a triangular structure, by the state vector. The second term describes the system nonlinearities which also assume a triangular structure. The gain of the proposed observer is issued from the resolution of a Lyapunov ordinary differential equation. The exponential convergence of the underlying observation error is established under a persistent excitation condition involving the system inputs and the state of the observer. In a second step, the observer design has been extended to a larger class of nonlinear systems where some state variables may intervene in a non triangular way. The notion of the characteristic indices associated to these state variables is then introduced and it allowed to define an extended triangular structure for which a high gain observer has been designed. Finally, it has been established that the proposed observers can be used as adaptive ones to jointly estimate the system state together with some unknown parameters and an adaptive form of these observers has been derived. The performance and main properties of the proposed observers have been illustrated in simulation by considering many examples throughout this thesis
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Goksu, Omer. "Shaft Transducerless Vector Control Of The Interior Permanent Magnet Motor With Speed And Position Estimation Using High Frequency Signal Injection And Flux Observer Methods." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609617/index.pdf.
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In this thesis, shaft transducerless vector control of Interior Permanent Magnet (IPM) motor with speed and position estimation using saliency based high frequency signal injection and fundamental model based flux observer methods will be investigated. The magnetic saliency characteristic of a 2.2-kW IPM motor will be experimentally extracted by means of high frequency signal injection. High frequency signal injection method will be used to estimate the speed and position at zero and low speed based on the magnetic saliency of the IPM motor. At high speed, fundamental model based flux observer method will be utilized for speed and position estimation. Seamless transition between the two estimation methods will be provided. Using the estimated speed and position information, the motor will be closed loop vector controlled and the drive motion performance over wide speed and load range will be investigated. The IPM motor drive and the estimation/control algorithms will be modeled and their performance will be demonstrated by detailed computer simulations. A three-phase voltage source inverter and a motor test bench will be built, and the estimation/control algorithms will be implemented on a DSP based motor control platform. The IPM motor drive system will be tested in the laboratory and the theory and simulation results will be verified by the experiments.
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Alvaro, Mendoza Carlos Enrique. "Control strategies for permanent magnet synchronous machines without mechanical sensors by sliding modes." Thesis, Ecole centrale de Nantes, 2022. http://www.theses.fr/2022ECDN0055.
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Cette thèse propose deux commandes adaptatives sans capteur basées sur l'approche en mode glissant pour les moteurs synchrones à aimants permanents internes (MSAP). Les stratégies proposées sont composées d'un observateur adaptatif en mode glissant d'ordre élevé (OAMGOE) en boucle fermée avec un contrôle adaptatif basé sur la super torsion, où les gains de contrôle etd'observateur de la stratégie proposée sont paramétrés en termes d'un seul paramètre. Ensuite, le principal avantage de cette stratégie est que les lois adaptables sont faciles à mettre en oeuvre, évitant les surestimations des gains qui augmententle broutage, réduisant le temps de réglage des gains et réduisant les dommages des actionneurs. En outre, une stratégie d'extraction d'erreur d'estimation de position angulaire est proposée. Ensuite, sur la base de ces informations et en utilisant un système virtuel sans paramètre, OAMGOE est conçu pour estimer la position angulaire et la vitesse dans une large plage devitesse, où les variables estimées fournies par cet observateur sont obtenues avec une plus grande précision, malgré les variations des paramètres, atteignant une plus grande robustesse. Ces états estimés sont utilisés dans la commande robuste proposée pour suivre une référence de vitesse souhaitée et une référence de courant d'axe d souhaitée. Une analyse de stabilité du système enboucle fermée est présentée, en utilisant une approche de Lyapunov. De plus, la stratégie proposée est validée tout au long du montageexpérimental et de simulation afin de montrer sonefficacitéThis thesis proposes two adaptive sensorless controls based on sliding mode approach for interior permanent magnet synchronous motor(IPMSM). The proposed strategies are composed of an Adaptive High-Order Sliding Mode Observer (AHOSMO) in closed-loop with an Adaptive Super- Twisting Control (ASTWC), where the control and observer gains of the proposed strategy are reparameterized in terms of a single parameter. Then, the main advantage of this strategy is the adaptable laws are easy to implement, avoiding overestimates of gains that increases of chattering, reducing the time to tune the gains, and reducing the damage of the actuators. Furthermore, a strategy for angular position estimation error extraction is proposed. Then, from this information and using a parameter-free virtual system, AHOSMO isdesigned for estimating the angular position and speed in a wide speed range, where the estimated variables provided by this observer are obtained with greater precision, despite the variations of the parameters, achieving greater robustness. These estimated states are used in the proposed robust control to track a desired reference of speed and direct-axis current. A stability analysis of the closedloop system is presented, using a Lyapunov approach. In addition, the proposed strategy is validated throughout experimental and simulationset-up in order to show its effectiveness
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Sadelli, Lounis. "Modélisation, observation et commande de robots vasculaires magnétiques." Thesis, Orléans, 2016. http://www.theses.fr/2016ORLE2065/document.
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La chirurgie minimalement invasive est un domaine de recherche très actif puisqu’elle permet d’envisagerdes thérapies ciblées et des diagnostics in situ tout en minimisant traumatismes, effets secondaires et tempsde convalescence. En particulier, l’utilisation de systèmes miniaturisés actionnés à distance ouvre la voie àune navigation dans le système cardiovasculaire, permettant ainsi le ciblage et l’intervention sur zones dif-ficilement accessibles du corps humain. L’objectif de cette thèse est de proposer i) un état de l’art sur lamodélisation des forces s’exerçant sur un ou plusieurs microrobots naviguant dans des vaisseaux sanguins,ii) des représentations d’état exploitables à des fins de commande et d’observation, iii) différentes synthèsesde lois de commande pour stabiliser un ou plusieurs microrobots le long d’une trajectoire de référence, iv)des observateurs d’état pour reconstruire les états non mesurables du système. Un microrobot magnétiquenaviguant dans un vaisseau sanguin subit la force de traînée, les forces surfaciques, de contact, d’interactionmagnétique, et son poids apparent. Son actionnement est assuré par l’application de champs ou de gradientsde champ magnétiques, et sa localisation est assurée par un imageur médical. La dynamique du ou desmicrorobots (système réduit) est sous forme d’état non linéaire affine en la commande avec dérive, et dé-pend de plusieurs paramètres physiologiques incertains, en particulier de la vitesse du sang, qui est difficileà mesurer. La dynamique du flux sanguin (système fluidique) est alors modélisée sous forme d’une repré-sentation d’état autonome, combinée avec le système réduit pour aboutir au système étendu. L’objectif decommande est de stabiliser les états du système réduit le long d’une trajectoire de référence. Une commandestabilisante est synthétisée par backstepping, mais elle n’est pas utilisable en l’état. Des observateurs baséssur le théorème de la valeur moyenne et sur une immersion sont synthétisés respectivement dans le cas oùla pulsation cardiaque est connue ou non. La stabilité du retour de sortie est alors démontrée. La stabilitéet la robustesse aux bruits de mesure, aux incertitudes paramétriques, et aux erreurs de modélisation desapproches proposées sont alors illustrées par des simulationsMinimally invasive surgery is an active research area since such systems have the potential to perform complex surgical procedures such as targeted therapies or in situ diagnosis, while minimizing trauma, side effects and recovery time. Miniaturized systems magnetically propelled by remote actuation can achieve swimming through the blood vessels network in order to provide targeted therapy, even for hard-to-reach human organs. This PhD thesis aims at addressing i) a review on the modeling of microrobots immersed in blood vessels, ii) a classification of the state space forms of such systems, iii) the synthesis of state feedbacks ensuring the stabilization of the microrobots along a reference trajectory, iv) the synthesis of observers to rebuild the unmeasured state variables. Magnetic microrobots swimming in a blood vessel face the hydrodynamic drag, surfacic and contact forces, magnetic interactions, and their apparent weight. These untethered robots are actuated by magnetic fields or magnetic gradients generation, and their localization is ensured by a medical imager. The microrobots dynamics (the so-called reduced system) lead to a nonlinear affine control subsystem with drift, and exhibits many uncertain physiological parameters, such as the blood velocity which can hardly be measured. The blood flow dynamics (the so-called fluidic system) are then modeled as an autonomous subsystem. These two subsystems result in an extended system describing the whole (robot and fluid) dynamics. The control objective is to stabilize the state of the reduced system along a reference trajectory, which is performed by an adaptive backstepping synthesis. Yet the full state is not accessible. We then synthesize either MVT or immersion based observers for the extended system, when the blood pulsation is either known or not. The output feedback stability is then proved. The stability and robustness to output noise, parametric uncertainty, and modeling errors are then illustrated by simulations
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Chumacero, Polanco Erik. "Velocity sensorless control switched reluctance motors." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112062/document.
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Dans ce mémoire de thèse, nous présentons la conception, l'analyse de la stabilité, les simulations numériques et aussi les résultats des expérimentes concernant différents contrôleurs de vitesse mécanique du moteur à réluctance variable (MRV).Dans les deux premiers chapitres une brève description de la physique et de la construction du MRV est présenté ainsi que le problème du contrôle d'être abordé, c'est la commande de vitesse sans capteur. Il est aussi présenté l'état de l'art de ce problème et certains des solutions proposées dans d'autres travaux. On propose notre solution et on présente un petit résumé des articles scientifiques qui ont été publiés dans des magazines et des conférences.Dans le chapitre numéro trois est présenté le design du contrôleur adaptatif et sans capteur du MRV. On suppose, dans une première étape que seule la vitesse mécanique est inconnue et la stabilité exponentielle uniforme des erreurs de suivement est obtenue. Dans une deuxième étape, les conditions d'opération sont aggravées et, en plus de la vitesse, les paramètres physiques sont également supposées inconnues, la stabilité asymptotique uniforme est obtenue dans ce cas. L'estimation des paramètres du MRV est garantie grâce à la condition de persistance d'excitation. Cette commande se compose de deux boucles, une boucle interne basée sur un contrôleur de type PI2D qui est particulièrement intéressant parce qu'il est libre de modèle; cette boucle entraîne les variables mécaniques -la position et la vitesse- vers une référence désirée. Une deuxième boucle de contrôle externe prend le courant électrique vers un ' "courant de référence virtuelle" qui est généré sur la base d'une approche de partage de couple. Le contrôleur propose est testé au niveau de simulations numériques qui sont également présentés.Dans le quatrième chapitre, une nouvelle approche de modélisation du MRV est utilisée pour concevoir le contrôleur. Dans ce scénario, on suppose que l'ensemble de l'état et tous les paramètres physiques sont disponibles, cette approche est pensée pour être adapté au contrôleur basé sur observateur, recherche qui est en cours de développement. Le contrôleur est composé de deux boucles, également que celui qui a été mentionné précédemment. Ce contrôleur est sélectionné parce qu'il est approprié pour le contrôle d'équivalence vraie, qui il s'agit de remplacer les «mesures physiques» provenant d'un capteur par les «observations» provenant d'un observateur. La mise en oeuvre numérique est effectuée sur Simulink de Matlab.Enfin, dans le chapitre cinq, les résultats expérimentaux qui ont été effectués pour évaluer la performance des contrôleurs proposés -ce sont les PI2D et adaptatif PI2D pour le modèle simplifie ainsi que le PID pour le nouveau approche de modélisation- sont présentés. Dans la première partie, une brève description de la construction du banc de tests utilisé est présenté ainsi que quelques-unes caractéristiques techniques. Trois différentes profils de vitesse sont imposées à chacun des contrôleurs proposés -ce sont la tangente hyperbolique, la rampe saturée et la référence sinusoïdal- et de bonnes résultats sont obtenus en considérant que la variable contrôlée est la vitesse. Le dernier chapitre correspond aux conclusions de la recherche effectuée ainsi qu'aux travaux futursIn this thesis dissertation we present the design, stability analysis, numerical simulations and physical experiments of different controllers designed to drive the mechanical velocity of the switched reluctance motor (SRM). In the First and Second Chapters a brief description of the physics and construction of the SRM is presented, as well as the problem of control to be aboard, that is the velocity sensorless control of motors and the state of the art of this problem. The proposed solution is introduced and a summary of the published papers as well as the contribution are also presented.In the Chapter number three is presented the velocity sensorless and adaptive control of the SRM. It is assumed, in a first stage, that only mechanical velocity is unknown, uniform exponential stability of the errors is achieved in this scenario. In a second stage, conditions are stressed and in addition to the velocity, physical parameters are also assumed unknown, uniform asymptotical stability is achieved in this case and parameters estimation is guaranteed under a persistence of excitation condition. This controller consists of two loops, an internal loop based on a PI2D–type controller which is of particular interest given it is free-model; this loop drives the mechanical variables –that is position and velocity- towards a desired reference. An external control loop takes the electrical current towards a ‘’virtual” current reference which is generated based on a torque share approach. The controller is tested on numerical simulations, which are also presented.In the fourth chapter, a new approach on the modeling of the SRM is utilized to design the controller, in this scenario is assumed that the whole state and all the physical parameters are available, however this approach is thought to be suitable to observer based controller, whose ongoing research is being performed. The controller is composed by two loops, similarly to the one mentioned previously. This controller is selected because it is suitable for certainty equivalence control, that is, to substitute the “measurements” by the “observations” coming from a virtual sensor. Numerical implementation is performed on Simulink of Matlab.Finally, in the Chapter five, the experimental results carried out to evaluate the performance of the proposed controllers are presented, these are the PI2D and the adaptive PI2D controllers for the simplified model and the $PID$ controller for the novel modeling approach. In the first part, a brief description of the construction of the utilized bench is presented as well as the some technical characteristics. Three different velocity profiles were imposed to each of the overmentioned controllers –these are the so called smooth step, the saturated ramp and the sinusoidal reference- and good results, considering that the controlled variable is the velocity, were obtained. The last chapter corresponds to the conclusions of the performed research as well as to the future work
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Tang, Chiang Cheng, and 江正塘. "Hyperchaotic Cryptography systems based on Adaptive Observer." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/61064884175768777924.
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碩士國立雲林科技大學
電機工程技術研究所
88
The thesis is mainly concerned with the secure communication systems and three subject are studied. In the first part, we emphasize on the so-called synchronization. By the Lyapunov stability theorem, we designed a state feedback gain to guarantee the synchronization for the master-slave chaotic systems. On the second part, the concept of adaptive observer is considered to design an adaptive control law for the unknown parameter or parameter with uncertainty for the chaotic system. So that the master-slave systems can be achieved the so-called adaptive algorithm synchronization. In the design procedure of the adaptive law, is well known speed-gradient algorithm is applied to derive a set of direct adaptive controller that guarantees the achievement of the adaptive synchronization. From the first and second part, low security is obvious in the communica -tion for master-slave systems by the chaotic circuit. It is due that an adaptive observer by only one of the state variable. How to exchange the security of master-slave chaotic system is a subject in the three part of the thesis. A novel scheme of hyperchaotic cryptographic system based on adaptive observer is presented. In the scheme, adaptive synchronization and cryptograph are combined to achieve a high secure communication by using the adaptive direct control from the two part in the thesis. Finally, some numerical simulation are give to demonstrate the efficiency of the proposed scheme.
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Chao, Chang-Chu, and 曹昌竹. "Observer-Based Indirect Adaptive Fuzzy Controller Design." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/55885022058143067869.
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碩士大同大學
電機工程學系(所)
94
In this paper, we build a new simplify model and design an observer-based fuzzy adaptive VSS tracking controller with time delay and external disturbance for our model. The simplify model can avoid complicated Lagrange’s equations, and get quite approximate dynamics for the actual system. The fuzzy approximation with adaptive algorithms are used to learn the dynamics of our model and observer design are introduced into our model. The observer is designed for the error dynamic and Lyapunov type stability is established under certain condition. Then, we apply a Riccati-like equation to solve the approximate error on the observer-based fuzzy adaptive VSS tracking control. The state with time delay effect on tracking error can be bounded via appropriate control force, and the error of state of observer can convergence to a bound at the same time. Finally, simulation result present the controller we design can control the model we propose to desired trajectory.
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Liao, Cheng-Tseng, and 廖承增. "Adaptive Variable Structure Observer for Uncertainties Systems." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/07148661794972830979.
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Lien, Te Chi, and 連得祺. "Observer Based Adaptive T-S Fuzzy Controller Design." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/86259592133043911001.
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Wen, Hong-Kang, and 溫宏康. "A GA-Tuned Adaptive PID Controller with Observer." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/8dam3p.
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碩士國立臺北科技大學
電機工程系所
96
Recently, since genetic algorithms have good capabilities of direct random search for global optimization with techniques mutation and extinction, they have drawn significant attention in various fields. In this thesis, we use a reduced form genetic algorithm to tune the parameters of PID controller online. PID controller, which is simple in structure and have good performance, is suitable to use in online control. However, PID controller have some drawbacks, for examples, in time-varying systems and nonlinear systems. The parameters of PID controller have traditionally been adjusted by expert experience and trial and error, and this takes time and our energy. Therefore, genetic algorithms can help this, and there are more and more design from this way. Adaptive control of systems has been an active area of research. Some adaptive control schemes for nonlinear systems via feedback linearization have been proposed. In this thesis, we proposed an online GA-Based direct adaptive PID controller . We tuned the parameters of PID controller by using the fitness function designed by the SPR-Lyapunov approach. Finally, we add a supervisory controller in order to guarantee the stability.