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Coordinating Agile Systems through the Model-based Execution of Temporal PlansLeaute, Thomas 28 April 2006 (has links)
Agile autonomous systems are emerging, such as unmanned aerial vehicles (UAVs), that must robustly perform tightly coordinated time-critical missions; for example, military surveillance or search-and-rescue scenarios. In the space domain, execution of temporally flexible plans has provided an enabler for achieving the desired coordination and robustness, in the context of space probes and planetary rovers, modeled as discrete systems. We address the challenge of extending plan execution to systems with continuous dynamics, such as air vehicles and robot manipulators, and that are controlled indirectly through the setting of continuous state variables.Systems with continuous dynamics are more challenging than discrete systems, because they require continuous, low-level control, and cannot be controlled by issuing simple sequences of discrete commands. Hence, manually controlling these systems (or plants) at a low level can become very costly, in terms of the number of human operators necessary to operate the plant. For example, in the case of a fleet of UAVs performing a search-and-rescue scenario, the traditional approach to controlling the UAVs involves providing series of close waypoints for each aircraft, which incurs a high workload for the human operators, when the fleet consists of a large number of vehicles.Our solution is a novel, model-based executive, called Sulu, that takes as input a qualitative state plan, specifying the desired evolution of the state of the system. This approach elevates the interaction between the human operator and the plant, to a more abstract level where the operator is able to Âcoach the plant by qualitatively specifying the tasks, or activities, the plant must perform. These activities are described in a qualitative manner, because they specify regions in the plantÂs state space in which the plant must be at a certain point in time. Time constraints are also described qualitatively, in the form of flexible temporal constraints between activities in the state plan. The design of low-level control inputs in order to meet this abstract goal specification is then delegated to the autonomous controller, hence decreasing the workload per human operator. This approach also provides robustness to the executive, by giving it room to adapt to disturbances and unforeseen events, while satisfying the qualitative constraints on the plant state, specified in the qualitative state plan.Sulu reasons on a model of the plant in order to dynamically generate near-optimal control sequences to fulfill the qualitative state plan. To achieve optimality and safety, Sulu plans into the future, framing the problem as a disjunctive linear programming problem. To achieve robustness to disturbances and maintain tractability, planning is folded within a receding horizon, continuous planning and execution framework. The key to performance is a problem reduction method based on constraint pruning. We benchmark performance using multi-UAV firefighting scenarios on a real-time, hardware-in-the-loop testbed. / SM thesis
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Thermal modeling, analysis, and control of a space suit /Campbell, Anthony B. January 1999 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1999. / Typescript. Vita. Includes bibliographical references (leaves [217]-221). Also available on the Internet.
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Προβλεπτικός έλεγχος για ιπτάμενα οχήματαΠιπεράκης, Στυλιανός 31 May 2012 (has links)
Στην προκειμένη εργασία μελετάται όλο το θεωρητικό υπόβαθρο για τον
προβλεπτικό έλεγχο για τις δύο κατηγορίες συστημάτων (Single Input-Single Output
SISO, Multiple Input-Multiple Output MIMO). Αρχικά μελετάται η πρώτη μορφή
προβλεπτικού ελέγχου που ήταν ο δυναμικός έλεγχος μητρών (DMC). Στην συνέχεια
ακολουθεί το πρόβλημα του βέλτιστου προβλεπτικού ελέγχου διακριτού χρόνου όπως
αυτό παρουσιάζεται και αναλύεται στην θεωρία του κ. Μaciejowski. Αμέσως μετά
μελετάται πάλι το πρόβλημα εύρεσης βέλτιστου προβλεπτικού ελέγχου διακριτού
χρόνου αλλά με την χρησιμοποίηση των διακριτών ορθοκανονικών συναρτήσεων
βάσης Laguerre όπως αναλύεται από τον κ. Wang στο βιβλίο του. Στις δύο επόμενες
ενότητες παρουσιάζονται οι ορθοκανονικές συναρτήσεις βάσης Laguerre συνεχούς
χρόνους καθώς και μια άλλη κατηγορία, οι συναρτήσεις Κautz και αναλύεται ο
τρόπος που υπολογίζεται ο προβλεπτικός έλεγχος συνεχούς χρόνου με τη χρήση
αυτών. Αφού ο αναγνώστης αποκτήσει τις γνώσεις που χρειάζονται πάνω στον
προβλεπτικό έλεγχο, ακολουθεί μια πρακτική εφαρμογή πάνω σε ένα ελικόπτερο 2
βαθμών ελευθερίας της Quanser. Εκεί αρχικά αφού περιγραφεί πλήρως η διάταξη
μελετάμε τα προβλήματα ελέγχου πρώτα με Pole Placement στην συνέχεια με LQR
καθώς και με την χρησιμοποίηση εκτιμητών κατάστασης όπως κάποιο παρατηρητή
(observer) ή φίλτρο Kalman πάντα με τη βοήθεια του Μatlab και του Simulink.
Επίσης όλη η θεωρία του ΜPC που μελετήσαμε έχει εφαρμοσθεί επιτυχώς σε
προσομοίωση στο Μatlab και Simulink. Παρουσιάζονται ο κώδικας που χρειάζεται
κάθε φορά καθώς και ενδιαφέροντα αποτέλεσματα για την απόκριση της διεργασίας.
Επιπλέον μελετήθηκε το toolbox του Matlab για τον προβλεπτικό έλεγχο (MPC
Toolbox). Τέλος οι παραπάνω έλεγχοι εφαρμόσθηκαν κατευθείαν στην πραγματική
διεργασία (μη γραμμική) και τα αποτελέσματα ήταν ικανοποιητικά. / This work presents all the necessary theory for the Model Predictive Control
for both system categories (Single Input-Single Output SISO, Multiple Input-Multiple
Output MIMO). To start, the earliest form of MPC called dynamic matrix control
(DMC) is studied. Then the optimal Model Predictive Control for discrete time is
analyzed based on the theory that Maciejowski presented. Afterwards the same
problem is studied using the discrete time Laguerre orthonormal base functions and
the optimal Model Predictive Control is computed as presented in Wang’s theory. In
the next two chapters the reader will be guided through the continuous time Laguerre
and Kautz orthonormal base functions and how they are used in computing the
optimal continuous time Model Predictive Control. Since the reader has acquired all
the necessary knowledge about MPC, a practical approach on the Quanser’s two
degrees of freedom helicopter follows. Initially, after we have fully described the
plant and all its components, we study the control problems using the pole placement
and LQR techniques along with state estimators such as observers and Kalman filter,
always in the Matlab and Simulink enviroment. Next, the MPC approaches we’ve
studied are applied successfully, again using Matlab and Simulink. In every case, all
the necessary programs and results are presented in detail. Addionally, the Matlab
MPC Toolbox is studied along with its results for the problem. Finally all those
controls are applied directly to the real nonlinear plant successfully and the results are
discussed.
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Application of control, modelling and optimisation to biomaterials manufacturingOnel, Oliver January 2013 (has links)
This thesis presents the work conducted during a three year research project in the field of Control Systems and Biomaterials Engineering. The findings are presented over seven chapters, starting with a thorough literature review of the existing methods and key technologies, and following through by highlighting the existing problems with the current methods and how they have been overcome. The data is presented in tables, figures and photographs to enhance understanding and clarification. The research focuses on two relatively new manufacturing methods in the field of Tissue Engineering. Both of the methods are used for creating materials for regeneration of human and animal tissue, with the aim of replacing the current surgical methods. The methods are viewed from a control systems perspective and improvements have been made with the implementation of new technologies and methods. Additionally, further advancements are presented on the theoretical modelling field of control systems, where the shortfalls of existent modelling methods are highlighted and solutions proposed.
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Commande des mouvements et de l'équilibre d'un robot humanoïde à roues omnidirectionnelles / Control of movements and balance of a humanoid robot with omnidirectional wheelsLafaye, Jory 02 July 2015 (has links)
La problématique traitée dans cette thèse concerne la commande et l'équilibre des robots humanoïdes disposant d'une base mobile à roues omnidirectionnelles. Les méthodes développées visent à atteindre de hautes performances dynamiques pour ce type de robot, tout en assurant stabilité et équilibre. Les robots humanoïdes ont en général un centre de masse relativement haut en comparaison avec leur surface de contact avec le sol. Ainsi, la moindre accélération des corps du robot induit une large variation de la répartition des forces de contact avec le sol. Si celles-ci ne sont pas correctement contrôlées, alors le robot peut tomber. De plus, le robot disposant d'une base mobile à roues, une perturbation peut l'amener aisément à basculer sur deux roues. Enfin, un intérêt particulier a été apporté à la réalisation d'une commande temps-réel implémentée sur le système embarqué du robot. Cela implique principalement des contraintes concernant le temps de calcul de la loi de commande. Afin de répondre à ces problèmes, deux modèles linéaires du robot ont été réalisés. Le premier permet de modéliser la dynamique du robot lorsque celui-ci possède toutes ses roues en contact avec le sol. Le second permet de modéliser la dynamique du robot lorsque celui-ci bascule sur deux de ses roues. Ces modèles ont été réalisés en prenant en compte la répartition massique du robot. Ainsi, il a été judicieux de le modéliser comme un système à deux masses ponctuelles, pouvant se déplacer sur un plan parallèle au sol. La première correspond au centre de masse de la base mobile, la seconde à celui du reste du robot. Ces modèles sont ensuite utilisés au sein de deux commandes prédictives, permettant de prendre en compte à chaque instant les contraintes dynamiques ainsi que le comportement du robot dans le futur. La première commande permet de contrôler les déplacements du robot lorsque celui-ci possède toutes ses roues en contact avec le sol, lui assurant de ne pas basculer. La seconde permet au robot de se rattraper d'une situation où une perturbation l'amène à basculer, afin de ramener toutes ses roues en contact avec le sol. Aussi, un superviseur disposant d'une machine à état à été réalisé afin de définir quelle loi de commande doit être exécutée à chaque instant. Ce superviseur utilise les capteurs disponibles sur le robot afin d'observer son état de basculement. Enfin, afin de valider expérimentalement le résultat des développements de cette thèse, une série d'expériences a été présentée, mettant en évidence les différents aspects de la loi de commande. Notamment, des essais ont été réalisés concernant le suivi de trajectoires non physiquement réalisables, le rejet de perturbations appliqués à la base mobile, la stabilisation du robot lors de son basculement, ainsi que la compensation de variations de l'inclinaison du sol. / The problem of this thesis concerns the control of the movements and the equilibrium of humanoid robots that have a mobile base with omnidirectionnal wheels. The developed methods aim to reach high dynamical performances for this type of robot, while ensuring it stability and equilibrium. Humanoid robots have generally a center of mass relatively high compared to its contact surface with the ground. Therefore, the slightest acceleration of the robot bodies induces a large variation of the distribution of the contact forces with the ground. If they are not properly controlled, the robot can fall. Moreover, the robot having a mobile base with wheels, a disturbance can easily bring it to tilt on two wheels. Finally, a specific interest have been provided about the realisation of a real time controler implemented on the embedded system of the robot. This implies some constraints about the computationnal time of the control law. In order to answer these problems, two linear models of the robot have been developed. The first allows to modelize the dynamics of the robot when it has all of its wheels in contact with the ground. The second allows to modelize the dynamics of the robot when it tilts on two of its wheels. These models have been developed by taking into account the mass distribution of the robot. These models have been subsequently used in two predictive control laws, allowing to take into account at every instant the dynamical constraints as weel as the future behavior of the robot. The first allows to control the movements of the robot when it has all of its wheels in contact with the ground, preventing it for tilting. The second allows the robot to recover itself in a situation when a disturbance bring it to tilt, in order to bring back all of its wheels in contact with the ground. Also, a supervisor that has a state machine has been made in order to define which control law has to be executed at each instant. This supervisor uses the available sensors on the robot in order to observe its tilt state. Finally, in order to validate experimentally the results of the developments of this thesis, a series of experiments has been presented, demonstrating some aspects of the control law. In particular, some tests have been made concerning the tracking of non physically feasible trajectories, the reject of disturbances applied on the mobile base, the stabilisation of the robot during its tilt, and the compensation of the variations of the ground inclination.
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Balance preservation and task prioritization in whole body motion control of humanoid robots / Préservation de l'équilibre et priorisation des tâches dans la commande du mouvement corps entier de robots humanoïdesSherikov, Alexander 23 May 2016 (has links)
Un des plus grands défis dans la commande des robots est de combler l'écart entre la capacité de mouvement de l'humain et des robots humanoïdes. La difficulté réside dans la complexité des systèmes dynamiques représentant les robots humanoïdes: la non linéarité, le sous-actionnement, le comportement non-lisse en raison de collisions et de frottement, le nombre élevé de degrés de liberté. De plus, les robots humanoïdes sont censés opérer dans des environnements non-déterministes, qui exigent une commande temps réel avancée.L'approche qui prévaut actuellement pour faire face à ces difficultés est d'imposer diverses restrictions sur les mouvements et d'employer des modèles approximatifs des robots. Dans cette thèse, nous suivons la même ligne de recherche et proposons une nouvelle approche pour la conception de contrôleurs corps entier qui préservent l'équilibre. L'idée principale est de tirer parti des avantages des modèles approximatifs et de corps entier en les mélangeant dans un seul problème de contrôle prédictif avec des objectifs strictement hiérarchisés.La préservation de l'équilibre est l'une des principales préoccupations dans la commande des robots humanoïdes. Des recherches antérieures ont déjà établi que l'anticipation des mouvements est essentiel à cet effet. Nous préconisons que l'anticipation est utile dans ce sens comme un moyen de maintenir la capturabilité du mouvement, i.e., la capacité de s'arrêter. Nous soulignons que capturabilité des mouvements prévus peut être imposée avec des contraintes appropriées. Dans la pratique, il est fréquent d'anticiper les mouvements du robot à l'aide de modèles approximatifs afin de réduire l'effort de calcul, par conséquent, un contrôleur séparé de mouvement du corps entier est nécessaire pour le suivi. Au lieu de cela, nous proposons d'introduire l'anticipation avec un modèle approximatif directement dans le contrôleur corps entier. En conséquence, les mouvements du corps entier générés respectent les contraintes de capturabilité et les mouvements anticipes du modèle approximatif prennent en compte les contraintes et les tâches désirées pour le corps entier. Nous posons nos contrôleurs du mouvement du corps entier comme des problèmes d'optimisation avec des objectifs strictement hiérarchisés. Bien que cet ordre de priorité soit commun dans la littérature, nous croyons qu'il est souvent mal exploité.Par conséquent, nous proposons plusieurs exemples de contrôleurs, où la hiérarchisation est utile et nécessaire pour atteindre les comportements souhaités. Nous évaluons nos contrôleurs dans deux scénarios simulés, où la tâche du corps entier du robot influence la marche et le robot exploite éventuellement un contact avec la main pour maintenir son équilibre en étant debout. / One of the greatest challenges in robot control is closing the gap between themotion capabilities of humans and humanoid robots. The difficulty lies in thecomplexity of the dynamical systems representing the said robots: theirnonlinearity, underactuation, discrete behavior due to collisions and friction,high number of degrees of freedom. Moreover, humanoid robots are supposed tooperate in non-deterministic environments, which require advanced real timecontrol. The currently prevailing approach to coping with these difficulties isto impose various limitations on the motions and employ approximate models ofthe robots. In this thesis, we follow the same line of research and propose anew approach to the design of balance preserving whole body motion controllers.The key idea is to leverage the advantages of whole body and approximate modelsby mixing them within a single predictive control problem with strictlyprioritized objectives.Balance preservation is one of the primary concerns in the control of humanoidrobots. Previous research has already established that anticipation of motionsis crucial for this purpose. We advocate that anticipation is helpful in thissense as a way to maintain capturability of the motion, i.e., the ability tostop. We stress that capturability of anticipated motions can be enforced withappropriate constraints. In practice, it is common to anticipate motions usingapproximate models in order to reduce computational effort, hence, a separatewhole body motion controller is needed for tracking. Instead, we propose tointroduce anticipation with an approximate model into the whole body motioncontroller. As a result, the generated whole body motions respect thecapturability constraints and the anticipated motions of an approximate modeltake into account whole body constraints and tasks. We pose our whole bodymotion controllers as optimization problems with strictly prioritizedobjectives. Though such prioritization is common in the literature, we believethat it is often not properly exploited. We, therefore, propose severalexamples of controllers, where prioritization is useful and necessary toachieve desired behaviors. We evaluate our controllers in two simulatedscenarios, where a whole body task influences walking motions of the robot andthe robot optionally exploits a hand contact to maintain balance whilestanding.
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Trajectory Sensitivity Based Power System Dynamic Security AssessmentJanuary 2012 (has links)
abstract: Contemporary methods for dynamic security assessment (DSA) mainly re-ly on time domain simulations to explore the influence of large disturbances in a power system. These methods are computationally intensive especially when the system operating point changes continually. The trajectory sensitivity method, when implemented and utilized as a complement to the existing DSA time domain simulation routine, can provide valuable insights into the system variation in re-sponse to system parameter changes. The implementation of the trajectory sensitivity analysis is based on an open source power system analysis toolbox called PSAT. Eight categories of sen-sitivity elements have been implemented and tested. The accuracy assessment of the implementation demonstrates the validity of both the theory and the imple-mentation. The computational burden introduced by the additional sensitivity equa-tions is relieved by two innovative methods: one is by employing a cluster to per-form the sensitivity calculations in parallel; the other one is by developing a mod-ified very dishonest Newton method in conjunction with the latest sparse matrix processing technology. The relation between the linear approximation accuracy and the perturba-tion size is also studied numerically. It is found that there is a fixed connection between the linear approximation accuracy and the perturbation size. Therefore this finding can serve as a general application guide to evaluate the accuracy of the linear approximation. The applicability of the trajectory sensitivity approach to a large realistic network has been demonstrated in detail. This research work applies the trajectory sensitivity analysis method to the Western Electricity Coordinating Council (WECC) system. Several typical power system dynamic security problems, in-cluding the transient angle stability problem, the voltage stability problem consid-ering load modeling uncertainty and the transient stability constrained interface real power flow limit calculation, have been addressed. Besides, a method based on the trajectory sensitivity approach and the model predictive control has been developed for determination of under frequency load shedding strategy for real time stability assessment. These applications have shown the great efficacy and accuracy of the trajectory sensitivity method in handling these traditional power system stability problems. / Dissertation/Thesis / Ph.D. Electrical Engineering 2012
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Modélisation et contrôle d'un réfrigérateur cryogénique Application à la station 800W à 4.5K du CEA Grenoble / Modelling and control of a cryogenic refrigeratorClavel, Fanny 18 January 2011 (has links)
Cette thèse concerne le développement de nouvelles stratégies de contrôle d’unréfrigérateur cryogénique soumis à de fortes variations de charge thermique. De telles perturbationsvont se rencontrer lors du refroidissement des aimants supraconducteurs des futurs réacteurs defusion (tokamak JT-60SA par exemple).La modélisation d’un réfrigérateur de test, offrant une capacité de refroidissement de 800Wà 4.5K, a été effectuée sous le logiciel Matlab/Simulink. Celle-ci est basée sur les équationsthéoriques de la thermodynamique, de la thermique et de l’hydraulique et prend en compte lespropriétés non linéaire de l’hélium à basse température.A partir de ce modèle, une stratégie de contrôle multivariable a été proposée sur les deuxparties du réfrigérateur : la station de compression et la boîte froide. Les résultats expérimentauxmontrent de nettes améliorations et une plus grande stabilité du réfrigérateur en présence decharges pulsées par rapport à la stratégie initiale (PI).Un observateur de la charge thermique du bain d’hélium liquide a également été développé.Le modèle utilisé est construit par identification à partir de mesures internes au réfrigérateur. Ilpourrait servir comme outil de surveillance aux opérateurs. / This thesis is concerned with the development of a novel control scheme on a heliumrefrigerator subject to high pulsed loads. Such disturbance will happen during the cooling of thesuperconductive magnet, used in tokamak configuration.A dynamical model of a cryogenic station, which offers a cooling capacity of 800W at4.5K, has been produced. The modelling is based on the theoretical equations of thermodynamics,thermal physics and hydraulics and takes into account the non linear properties of helium at lowtemperature.Based on this model, a new control strategy has been developed for each of the two parts ofthe refrigerator: the warm compression system and the cold box. Experimental results showsignificant improvement with multivariable controllers as compared with the PIDs in the presenceof high pulsed loads.An observer of the thermal load of the helium bath has also been developed. The model isconstructed by identification using internal measures of the refrigerator. It can be used as conditionmonitoring tool for operators.
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On Identification and Control of Multivariable Systems Including Multiple Delays and Their Application to Anesthesia Control / 複数のむだ時間を含む多変数系の同定と制御およびそれらの麻酔制御への応用 / フクスウ ノ ムダ ジカン オ フクム タヘンスウケイ ノ ドウテイ ト セイギョ オヨビ ソレラ ノ マスイ セイギョ エ ノ オウヨウSawaguchi, Yoshihito 24 March 2008 (has links)
This thesis proposes novel methods for identification and control of multivariable systems including multiple delays and describes their application to control of general anesthesia administration. First, an identification method for multivariable systems whose input and output paths have different time delays is presented. Second, a state predictor for multivariable systems whose input and output paths have different time delays is proposed. Third, the state predictor is used for constructing a state-predictive servo control system for controlled processes whose output paths have different time delays. A robust stability analysis method of the state-predictive servo control system is also examined. Furthermore, based on results of these theoretical studies, control systems for use in general anesthesia administration are developed. First, an identification method for multivariable systems whose input and output paths have different time delays is proposed. This method comprises two steps. In the first step, the delay lengths are estimated from the impulse response matrix identified from input and output (I/O) sequences using a subspace identification algorithm. In the second step, I/O sequences of a delay-free part are constructed from the original sequences and the delay estimates, and the system matrices of the delay-free part are identified. The proposed method is numerically stable and efficient. Moreover, it requires no complex optimization to obtain the delay estimates, nor does it require an assumption about the structure of the system matrices. Second, a state predictor is proposed for multivariable systems whose input and output paths have different time delays. The predictor consists of a full-order observer and a prediction mechanism. The former estimates a vector consisting of past states from the output. The latter predicts the current state from the estimated vector. The prediction error converges to zero at an arbitrary rate, which can be determined using pole assignment method, etc. In the proposed predictor, the interval length of the finite interval integration fed to the observer is shorter than that of an existing delay-compensating observer. Consequently, the proposed predictor is more numerically accurate than the delay-compensating observer. Using the proposed state predictor, a design method of a state-predictive servo controller is described for multivariable systems whose output paths have different time delays. Furthermore, a sufficient stability condition of the state-predictive servo control system against parameter mismatches is derived. Using a characteristic equation of the perturbed closed-loop system, a stability margin can be given on a plane whose axes correspond to the magnitudes of the mismatches on system matrices and on delay lengths. In the remainder of this thesis, development of anesthesia control systems is described to illustrate an application of the theoretical results described above. First, a hypnosis control system is presented. This system administers an intravenous hypnotic drug to regulate an electroencephalogram-derived index reflecting the patient’s hypnosis. The system comprises three functions: i) a model predictive controller that can take into account effects of time delay adequately, ii) an estimation function of individual parameters, and iii) a risk-control function for preventing undesirable states such as drug over-infusion or intra-operative arousal. Results of 79 clinical trials show that the system can reduce the total amount of drug infusion and maintain hypnosis more accurately than an anesthesiologist’s manual adjustment. Second, a simultaneous control system of hypnosis and muscle relaxation is described. For development of this system, a multivariable model of hypnosis and muscle relaxation is identified using the method proposed in this thesis. Then a state-predictive servo control system is designed for controlling hypnosis and muscle relaxation. Finally, the control system’s performance is evaluated through simulation. The resultant simultaneous control system satisfies the performance specifications of settling time, disturbance rejection ability, and a robust stability range. Although this system is not fully developed, the procedure of constructing this control system demonstrates the effectiveness of the proposed methods: the identification method for systems whose input and output paths have different time delays and the design and stability analysis methods of the state-predictive servo control system. / Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第13820号 / 工博第2924号 / 新制||工||1432(附属図書館) / 26036 / UT51-2008-C736 / 京都大学大学院工学研究科電気工学専攻 / (主査)教授 小林 哲生, 教授 萩原 朋道, 准教授 古谷 栄光 / 学位規則第4条第1項該当
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Navigation prédictive d'un microrobot magnétique : Instrumentation, commande et validation / Predictive navigation of a magnetic microrobot : instrumentation, control ans validationBelharet, Karim 04 October 2013 (has links)
Un grand nombre de traitements sont aujourd'hui disponibles pour la cancérologie, dont l'objectif est d'éliminer tous les tissus cancéreux en minimisant les dommages occasionnés sur les tissus sains. La chimio-embolisation est considérée comme un régime de traitement localisé, préconisé pour certains cancers. Cependant, le ciblage des tumeurs profondément enfouies par chimio-embolisation est actuellement limité en raison de la taille des cathéters. Compte tenu des échelles envisagées, l'utilisation des microrobots magnétiquement guidés est l'une des approches les plus prometteuses. L'objectif de cette thèse consiste à développer les outils permettant à des microrobots endovasculaires (ou transporteurs magnétiques), de naviguer dans le corps humain, en utilisant les gradients magnétiques d'un appareil IRM clinique amélioré. Pour cela, une compréhension approfondie de l'environnement d'évolution du microrobot est une étape au préalable, en vue d'établir des stratégies de navigation adéquates. La variation des paramètres physiologiques de l'humain et l'utilisation d'un scanner IRM nécessitent d'une part, une robustesse du contrôleur vis-à-vis des erreurs de modélisation, et d'autre part, l'anticipation du comportement du système. A cet effet, la commande prédictive, trouve ici toute son efficacité pour résoudre les problèmes de poursuite. En outre, une plateforme d'instrumentation a été conçue au sein du laboratoire en vue de démontrer les concepts proposés, et de valider les stratégies de navigation prédictives développées dans nos travaux. Puis, dans un deuxième temps, nous avons intégré ces approches dans une plateforme d'IRM clinique. / Today, many cancer treatments are available, whose goal is to kill the cancerous tissue and to minimize damage to healthy tissue. Chemoemobilization is considered as a targeting treatment recommended for some cancers. However, targeting tumor deeply buried using chemoemobilization is currently limited due to the size of the microcatheters. Taking into account the scales considered, the use of magnetically guided microrobots is one of the most promoting approaches. The objective of this thesis is to develop tools for endovascular microrobots (or carriers), navigate in the human body using magnetic gradients of an improved clinical MRI. For this, understanding microrobot evolution environment is a first step, in order to develop appropriate navigation strategies. The variation of the human physiological parameters and the use of MRI scanner require a robustness of the controller to the modeling errors, and the anticipation of the system behavior. For this, predictive control is fully effective to solve the tracking problem. In addition, an instrumentation platform was designed to demonstrate the proposed concepts and to validate the predictive navigation strategies developed in our work. Then, in a second step, we investigated these approaches in clinical MRI platform.
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