Dissertations / Theses on the topic 'Holonomic system'

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1

Yuan, Hongliang. "Control of NonH=holonomic Systems." Doctoral diss., University of Central Florida, 2009. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2751.

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Many real-world electrical and mechanical systems have velocity-dependent constraints in their dynamic models. For example, car-like robots, unmanned aerial vehicles, autonomous underwater vehicles and hopping robots, etc. Most of these systems can be transformed into a chained form, which is considered as a canonical form of these nonholonomic systems. Hence, study of chained systems ensure their wide applicability. This thesis studied the problem of continuous feed-back control of the chained systems while pursuing inverse optimality and exponential convergence rates, as well as the feed-back stabilization problem under input saturation constraints. These studies are based on global singularity-free state transformations and controls are synthesized from resulting linear systems. Then, the application of optimal motion planning and dynamic tracking control of nonholonomic autonomous underwater vehicles is considered. The obtained trajectories satisfy the boundary conditions and the vehicles' kinematic model, hence it is smooth and feasible. A collision avoidance criteria is set up to handle the dynamic environments. The resulting controls are in closed forms and suitable for real-time implementations. Further, dynamic tracking controls are developed through the Lyapunov second method and back-stepping technique based on a NPS AUV II model. In what follows, the application of cooperative surveillance and formation control of a group of nonholonomic robots is investigated. A designing scheme is proposed to achieves a rigid formation along a circular trajectory or any arbitrary trajectories. The controllers are decentralized and are able to avoid internal and external collisions. Computer simulations are provided to verify the effectiveness of these designs.
Ph.D.
School of Electrical Engineering and Computer Science
Engineering and Computer Science
Electrical Engineering PhD
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2

Rebahi, Yacine. "Irrégularité des D-modules algébriques holonomes." Université Joseph Fourier (Grenoble ; 1971-2015), 1996. http://www.theses.fr/1996GRE10205.

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Ce travail est consacre a l'etude de l'irregularite des systemes differentiels algebriques holonomes. Nous demontrons que les complexes de solutions de type exponentiel, associes a ces systemes, sont a cohomologie constructible et nous calculons leur caracteristique d'euler poincare. Pour cela, et dans le cas d'un fibre de rang un, nous utilisons un passage a l'infini qui nous permet de nous ramener a des resultats connus pour des solutions formelles de croissance appropriee pour des systemes analytiques holonomes. D'autre part, si nous microlocalisons nos constructions, nous obtenons des resultats analogues dans le cas d'un fibre de rang quelconque
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3

Delmas, Pierre. "Génération active des déplacements d'un véhicule agricole dans son environnement." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2011. http://tel.archives-ouvertes.fr/tel-00669534.

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Dans ces travaux, nous proposons un système de guidage automatique pour la navigation sûre d'un robot mobile dans un monde ouvert. Le principe est de contrôler la direction et la vitesse du véhicule afin de préserver son intégrité physique et celle de son environnement. Cela se traduit par la généralisation du concept d'obstacle permettant d'estimer l'espace de vitesses admissibles par le véhicule en fonction de la surface de navigation, des capacités du véhicule et de son état. Afin d'atteindre cet objectif, le système doit pour chaque itération : 1) fournir à la tâche de perception une zone sur laquelle elle devra focaliser son attention pour la reconstruction de l'environnement ; 2) générer des trajectoires admissibles par le véhicule ; 3) estimer le profil de vitesse admissible pour chacune d'entre elles ; 4) pour finir, sélectionner la plus optimale par rapport à un critère prédéfini. Des résultats simulés et obtenus sur un démonstrateur réel permettent d'analyser les performances obtenues du système face à des scénarios divers et en démontre la pertinence.
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4

Ortiz, Morales Daniel. "Virtual Holonomic Constraints: from academic to industrial applications." Doctoral thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-87707.

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Whether it is a car, a mobile phone, or a computer, we are noticing how automation and production with robots plays an important role in the industry of our modern world. We find it in factories, manufacturing products, automotive cruise control, construction equipment, autopilot on airplanes, and countless other industrial applications.         Automation technology can vary greatly depending on the field of application. On one end, we have systems that are operated by the user and rely fully on human ability. Examples of these are heavy-mobile equipment, remote controlled systems, helicopters, and many more. On the other end, we have autonomous systems that are able to make algorithmic decisions independently of the user.         Society has always envisioned robots with the full capabilities of humans. However, we should envision applications that will help us increase productivity and improve our quality of life through human-robot collaboration. The questions we should be asking are: “What tasks should be automated?'', and “How can we combine the best of both humans and automation?”. This thinking leads to the idea of developing systems with some level of autonomy, where the intelligence is shared between the user and the system. Reasonably, the computerized intelligence and decision making would be designed according to mathematical algorithms and control rules.         This thesis considers these topics and shows the importance of fundamental mathematics and control design to develop automated systems that can execute desired tasks. All of this work is based on some of the most modern concepts in the subjects of robotics and control, which are synthesized by a method known as the Virtual Holonomic Constraints Approach. This method has been useful to tackle some of the most complex problems of nonlinear control, and has enabled the possibility to approach challenging academic and industrial problems. This thesis shows concepts of system modeling, control design, motion analysis, motion planning, and many other interesting subjects, which can be treated effectively through analytical methods. The use of mathematical approaches allows performing computer simulations that also lead to direct practical implementations.
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5

Töyrä, Daniel. "Fidelity of geometric and holonomic quantum gates for spin systems." Thesis, Uppsala universitet, Teoretisk kemi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-222152.

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Geometric and holonomic quantum gates perform transformations that only dependon the geometry of a loop covered by the parameters controlling the gate. Thesegates require adiabatic time evolution, which is achieved in the limit when the looptakes infinite time to complete. However, it is of interest to also know thetransformation properties of the gates for finite run times. It has been shown [Phys.Rev. A 73, 022327 (2006)] that some holonomic gates for a trapped ion system showrevival structures, i.e., for some finite run time the gate performs the sametransformation as it does in the adiabatic limit. The purpose of this thesis is to investigate if similar revival structures are shown alsofor geometric and holonomic quantum gates for spin systems. To study geometricquantum gates an NMR setup for spin-1/2 particles is used, while an NQR setup forspin-3/2 particles is used to study holonomic quantum gates. Furthermore, for thegeometric quantum gates the impact of some open system effects are examined byusing the quantum jump approach. The non-adiabatic time evolution operators of thesystems are calculated and compared to the corresponding adiabatic time evolutionoperators by computing their operator fidelity. The operator fidelity ranges between0 and 1, where 1 means that the gates are identical up to an unimportant phasefactor. All gates show an oscillating dependency on the run time, and some Abeliangates even show true revivals, i.e., the operator fidelity reaches 1.
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6

Stroot, Holger [Verfasser]. "Strong Approximation of Stochastic Mechanical Systems with Holonomic Constraints / Holger Stroot." München : Verlag Dr. Hut, 2019. http://d-nb.info/1196415595/34.

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7

Frolík, Stanislav. "Geometrická teorie řízení na nilpotentních Lieových grupách." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-399583.

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This thesis deals with the theory of geometric control of the trident robot. The thesis describes the basic concepts of differential geometry and control theory, which are subsequently used for describing various mechanisms. Finally, the thesis proposes the management using inferred results.
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8

Seiler, Konstantin. "Fast trajectory generation and correction for non-holonomic systems exploiting Lie group symmetries." Thesis, The University of Sydney, 2013. http://hdl.handle.net/2123/10117.

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Sampling based motion planning is a popular motion planning technique for systems with many degrees of freedom in continuous state spaces. In particular the class of Rapidly exploring Random Tree algorithms (RRTs) has wide-spread use as they can be applied to a broad range of systems. Subsequently many extensions and variations to the RRT algorithm are known today. Many results, however, are not applicable in the case of non-holonomic and underactuated systems due to the difficulty in obtaining the required length-of-shortest-path distance metric and corresponding local planner. Instead, by focussing on changing existing paths this work develops algorithmic frameworks that allow faster motion planning specifically in the domain of non-holonomic underactuated systems. In order to adapt the paths efficiently, symmetries exhibited by the system are exploited by the algorithms. The particular focus of this work is on continuous symmetry groups that constitute a Lie group and thus allow for fast and powerful transformations of existing trajectories. Two methods are proposed to address this. The first allows path correction of an arbitrary path to reach a given goal. It works by applying small changes to selected small segments of a given trajectory and propagates their effects in a fast way using symmetry operations that avoid costly reintegration along the whole path. The second method allows the RRT algorithm to plan for a whole family of paths simultaneously to achieve greater coverage of the state space. The algorithm identifies those symmetry orbits, or subspaces thereof, that contain valid paths and propagates their states throughout the planning process. Both methods can be employed together and complement each other well.
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9

Mauny, Johan Raphaël. "Modélisation dynamique des systèmes non-holonomes intermittents : application à la bicyclette." Thesis, Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire, 2018. http://www.theses.fr/2018IMTA0113.

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Cette thèse traite de la modélisation dynamique des systèmes non-holonomes intermittents et de son application à la bicyclette 3D de Whipple. Pour cela, nous nous sommes appuyés sur un ensemble d'outils en mécanique géométrique (réduction Lagrangienne et projection dans le noyau des contraintes cinématiques essentiellement). Dans un premier temps, nous avons traité le cas de la bicyclette persistante. En définissant l'espace des configurations du vélo comme un fibré principal de groupe structural SE(3), nous avons obtenu un modèle des points de contact et des contraintes exempt de toute non-linéarité associée à un paramétrage de type coordonnées généralisées. Cette formulation nous a permis d'obtenir le noyau des contraintes sous une forme symbolique sans singularité. Nous avons alors produit un modèle symbolique de la dynamique de la bicyclette persistante en utilisant la méthode de réduction par projection de sa dynamique libre dans le sous espace de ses vitesses admissibles. Cette approche étend le cadre général mis au point ces dernières années pour la locomotion bio-inspirée. Profitant de la structure de SE(3), un modèle de la bicyclette intermittente a été proposé dans le cadre d'une approche événementielle. L'adoption du modèle physique de l'impact plastique, nous a permis d'étendre la méthode de réduction par projection au cas intermittent. Nous avons alors comparé notre approche "réduite" à l'approche classiquement utilisée et avons montré qu'elles partageaient une interprétation géométrique commune. Ces outils ont finalement été appliqués à la simulation de la bicyclette intermittente afin d'illustrer la richesse de sa dynamique
This thesis deals with the dynamic modelling of intermittent non-holonomic systems andits application to the Whipple 3D bicycle. To that end, we relied on a set of tools in geometric mechanics (mainly Lagrangian reduction and the projection in the kernel of the kinematic constraints). In the first instance, we have addressed the case of the bicycle subjected to persistent contacts. By defining the space of the bicycle configurations as a principal fibre bundle with SE(3) as structural group, we obtained a model of the contact points and of the constraints free of any non-linearities associated with a generalized coordinate type configuration. This formulation allowed us to obtain the kernel of the constraints in a symbolic form without singularity. We then produced a symbolic model of the dynamics ofthe bicycle subjected to persistent contacts using the projection reduction method of its free dynamics in the subspace of its permissible speeds. This approach extends the general framework developed in recent years for bio-inspired locomotion. Taking advantage of the structure of SE(3), a model of the intermittent bicycle was proposed as part of an event-driven approach. Moreover, the adoption ofthe physical model of plastic impact has allowed us to extend the projection reduction method to the intermittent case. We then compared our "reduced" approach to the conventional approach and showed that they shared a common geometric interpretation. These tools were finally applied to the simulation of the intermittent bicycle to illustrate its rich dynamics
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10

Abdel, Gadir Basil. "Analyse microlocale des systèmes différentiels holonomes." Grenoble 1, 1992. http://www.theses.fr/1992GRE10071.

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Nous nous placerons dans le contexte analytique-complexe. Les systemes differentiels holonomes traduisent algebriquement les systemes differentiels lineaires surdetermines maximaux, et ils generalisent les fibres vectoriels a connexion integrale. La question de leur classification (jusqu'ici limitee au cas des systemes a singularite reguliere et a celui d'une variable) a ete entreprise par un certain nombre d'auteurs, parmi lesquels il faut notamment citer m. Kashiwara et b. Malgrange. Dans cette direction nous contribuons aux resultats lies a la description microlocale (i. E. Locale sur l'espace cotangent) des systemes differentiels holonomes a singularite arbitraire. Nous generalisons un theoreme de finitude de b. Malgrange en utilisant un lemme de m. Kashiwara et t. Kawai affirmant que le germe du support d'un systeme microdifferentiel holonome possede (apres une transformation symplectique convenable) une position generique. Le theoreme de finitude assure qu'un tel systeme microdifferentiel admet un reseau microdifferentiel de type fini sur l'anneau commutatif des fonctions holomorphes. A l'aide de ce resultat, nous demontrons que ces systemes microdifferentiels holonomes sont en fait des systemes differentiels holonomes. En outre, nous formulons et nous etudions la transformation de fourier-deligne-katz-laumon-malgrange pour les systemes differentiels holonomes ainsi trouves. Ici, le resultat interessant est que l'etude de tels objets se ramene a celle des connexions meromorphes etudiee par p. Deligne et b. Malgrange
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11

Borzone, Tommaso. "Decentralized control of multi-agent systems : a hybrid formalism." Thesis, Université de Lorraine, 2019. http://www.theses.fr/2019LORR0078/document.

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Au cours des dernières années, les problèmes multi-agents ont été étudiés de manière intensive par la communauté de la théorie du contrôle. L'un des sujets les plus populaires est le problème de consensus où un groupe d'agents parvient à un accord sur la valeur d'un certain paramètre ou d’une variable. Dans ce travail, nous nous concentrons sur le consensus des réseaux d'agents avec une dynamique non linéaire de poursuite de référence. Nous utilisons des interactions sporadiques modélisées par la détection relative, pour traiter le consensus décentralisé des références. La référence est donc utilisée pour alimenter la dynamique de poursuite de chaque agent. L'analyse de stabilité du système globale a nécessitée l'utilisation d'outils théoriques propre de la théorie des systèmes hybrides, en raison de la double nature de l'approche en deux étapes. L'analyse est effectuée en tenant compte de différents scénarios de topologie et interactions. Pour chaque cas, une condition suffisante de stabilité est fournie, en termes de temps minimum autorisé entre deux mises à jour de référence consécutives. Le cadre proposé est appliqué aux missions de rendez-vous et de réalisation de formation pour les robots mobiles non-holonomes. Le même problème est abordé dans le contexte d'une application réelle sur le terrain, à savoir un système de gestion de flotte pour un groupe de véhicules robotisés déployés dans un environnement industriel à des fins de surveillance et de collecte de données. Le développement d'une telle application a été motivé par le fait que cette thèse s'inscrit dans le cadre du projet FFLOR, développé par le département de recherche technologique du CEA tech
Over the last years, multi-agents problems have been extensively studied from the control theory community. One of the most popular multi-agents control topics is the consensus problem where a group of agents reaches an agreement over the value of a certain parameter or variable. In this work we focus our attention on the consensus problem of networks of non-linear reference tracking agents. In first place, we use sporadic interactions modeled by relative sensing to deal with the decentralized consensus of the references. The reference is therefore feeded the tracking dynamics of each agent. Differently from existent works, the stability analysis of the overall system required the usage of hybrid systems theory tools, due to dual nature of the two stages approach. The analysis is carried out considering different scenarios of network topology and interactions. For each case a stability sufficient condition in terms of the minimum allowed time between two consecutive reference updates is provided. The proposed framework is applied to the rendez-vous and formation realisation tasks for non-holonomic mobile robots, which appear among the richest research topics in recent years. The same problem is addressed in the context of a real field application, namely a fleet management system for a group of robotic vehicles deployable in an industrial environment for monitoring and data collection purpose. The development of such application was motivated by the fact that this thesis is part of the Future of Factory Lorraine (FFLOR) project, developed by the technological research department of the Commissariat à l'énergie atomique et aux énergies alternatives (CEA tech)
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12

Mettin, Uwe. "Applications of the Virtual Holonomic Constraints Approach : Analysis of Human Motor Patterns and Passive Walking Gaits." Licentiate thesis, Umeå : Department of Applied Physics and Electronics, Umeå University, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1873.

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13

Shedied, Samy Aly. "Optimal Control for a Two Player Dynamic Pursuit Evasion Game; The Herding Problem." Diss., Virginia Tech, 2002. http://hdl.handle.net/10919/26110.

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In this dissertation we introduce a new class of pursuit-evasion games; the herding problem. Unlike regular pursuit evasion games where the pursuer aims to hunt the evader the objective of the pursuer in this game is to drive the evader to a certain location on the x-y grid. The dissertation deals with this problem using two different methodologies. In the first, the problem is introduced in the continuous-time, continuous-space domain. The continuous time model of the problem is proposed, analyzed and we came up with an optimal control law for the pursuer is obtained so that the evader is driven to the desired destination position in the x-y grid following the local shortest path in the Euler Lagrange sense. Then, a non-holonomic realization of the two agents is proposed. In this and we show that the optimal control policy is in the form of a feedback control law that enables the pursuer to achieve the same objective using the shortest path. The second methodology deals with the discrete model representation of the problem. In this formulation, the system is represented by a finite di-graph. In this di-graph, each state of the system is represented by a node in the graph. Applying dynamic programming technique and shortest path algorithms over the finite graph representing the system, we come up with the optimal control policy that the pursuer should follow to achieve the desired goal. To study the robustness, we formulate the problem in a stochastic setting also. We analyze the stochastic model and derive an optimal control law in this setting. Finally, the case with active evader is considered, the optimal control law for this case is obtained through the application of dynamic programming technique.
Ph. D.
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14

Li, Shunjie. "Géométrie et classification des systèmes de contact : applications du contrôle des systèmes mécaniques non holonomes." Phd thesis, INSA de Rouen, 2010. http://tel.archives-ouvertes.fr/tel-00665223.

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Dans la première partie de cette thèse, nous caractérisons complètement toutes les x-sorties plates et leurs lieux singuliers pour un système avec deux contrôles qui est équivalent au système chaîné. Nous appliquons aussi ce résultat au système de robot mobile avec des remorques pour calculer toutes ses x-sorties plates. Dans la deuxième partie, nous présentons un nouveau modèle pour le système à n-barres dans l'espace de dimension m+1. Nous montrons que ce système est localement équivalent au système m-chaîné et caractérisons aussi ses lieux singuliers. Ensuite, nous analysons sa propriété de platitude et donnons ses sorties plates minimales. Dans la troisième partie, nous donnons des conditions nécessaires et suffisantes pour qu'une distribution soit équivalente à la distribution de Cartan pour des surfaces. Finalement, dans la quatrième partie, nous donnons des conditions nécessaires et suffisantes vérifiables pour qu'un système multi-entrées soit linéarisable par bouclage orbital.
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Belato, Debora. "Analise não linear de sistemas dinamicos holonomos não ideais." [s.n.], 2002. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264610.

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Orientadores : Hans Ingo Weber, Jose Manoel Balthazar, João Maurício Rosário
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
Made available in DSpace on 2018-08-01T20:05:10Z (GMT). No. of bitstreams: 1 Belato_Debora_D.pdf: 22468929 bytes, checksum: b008a52ab3fb5afd92f7489482994f7e (MD5) Previous issue date: 2002
Resumo: Sistemas dinâmicos da mecânica muitas vezes unem o comportamento descrito por leis de movimento à dinâmica do seu funcionamento. Sua solução passa por hipóteses simplificadoras adotadas para obter um modelo matemático representativo e útil. Quando a fonte de energia utilizada no acionamento do movimento possui potência limitada, isto é, não há potência suficiente no motor para um correto funcionamento do mecanismo, o sistema dinâmico é dito não-ideal. Sob esta suposição, investiga-se numericamente neste trabalho o sistema não linear de um problema específico procurando identificar as condições não lineares e não-ideais de movimento. São empregadas técnicas clássicas de análise de sistemas não lineares, porém é desenvolvida uma técnica numérica nova, capaz de descrever o comportamento dinâmico das principais soluções do sistema. Esta técnica consiste no cálculo de funções polinomiais capazes de descrever a estabilidade de um conjunto de soluções em uma região limitada do retrato de fase e que fornecem também um completo diagrama de bifurcação das soluções sem que tenha sido feita qualquer simplificação nas equações diferenciais
Abstract: Several times the mechanical systems join the behavior described by laws of motion to the dynamic of their operation. Their solution pass by adopted simplified hypotheses in order to obtain a representative and helpful mathematical model. When the energy source used in the bringing to the action of the motion has limited power, i.e., there is not sufficient power in the motor for a proper working of the mechanism and the dynamic system is called nonideal. On this supposition, we numerically investigate in this work the nonlinear system of a specific problem looking for identify the nonideal and nonlinear conditions of the motion. Classical techniques of analyses of nonlinear systems are used, however it is develop a new numerical approaching, able to describe the dynamical behavior of the main solutions of the system. This technique consists in the calculation of the polynomials functions that describe the stability of a set of solutions concerning a bounded region on the phase portrait and they also provide a complete bifurcation diagram of the solutions without that any simplification in the diferential equations has been done
Doutorado
Mecanica dos Sólidos e Projeto Mecanico
Doutor em Engenharia Mecânica
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Rodriguez, Sebastián. "From analysis to design of holonic multi-agent systems : a framework, methodological guidelines and applications." Besançon, 2006. http://www.theses.fr/2005BESA2058.

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Le travail présenté dans cette thèse concerne le développement d'un Framework pour les Systèmes Multi-Agents Holoniques. Ce type de système se compose de structures auto-similaires appelées holons. Un ensemble de holons peut être vu, selon le niveau d'observation, comme une entité unique ou comme un groupe de holons en interactions. Pour concevoir un framework générique et modulaire, nous utilisons une approche organisationnelle. Nous définissons les comportements des entités du framework en termes de rôles et d'interactions. Le framework met l'accent sur la modélisation et la représentation de trois aspects importants d'un SMA Holonique. Structure et Gestion d'un Holon : cette partie du framework prend en compte l'organisation des membres et la gestion du super-holon. Une organisation spécifique est proposée pour définir les statuts des membres vis-à-vis de leur super-holon. Interactions dépendantes du Problème : Pour réaliser les buts et les tâches du super-holon, les membres doivent interagir et coordonner leurs actions. Ces comportements, dépendants du problème, constituent les organisations internes. Notre framework offre aussi la possibilité de modéliser ces aspects. Dynamique : La dynamique est une caractéristique inhérente des SMA. Le framework considère également deux caractéristiques intrinsèques aux SMA holoniques : la Fusion (création et intégration dans le super-holon) et l'Auto-Organisation. Chaque organisation est modélisée en utilisant le modèle Rôle-Interaction-Organisation (RIO). Ce modèle offre une spécification formelle des rôles et permet la vérification et la validation des spécifications. Le framework a été formellement spécifié et cette formalisation, nous a permis de prouver d'importantes propriétés importantes sur l'auto-organisation du système. Nous proposons également une méthodologie pour l'analyse et la conception des systèmes complexes basée sur la notion de "Vues du Système". Chaque vue se consacre à un aspect particulier du système, et est représentée par une holarchie. Deux applications illustrent les concepts présentés dans ce travail. La première applique le framework au cas du Maillage Adaptatif pour le dimensionnement de réseaux radiomobiles. Cette application illustre le raffinement de la partie auto-organisation du framework et la spécification formelle d'un problème réel. La deuxième présente quant à elle, l'application des SMA holoniques pour la simulation d'un important site industriel. Plusieurs holarchies sont utilisées pour capturer les interactions entre les chaînes de production et le trafic routier interne au site. Pour implémenter ces concepts nous proposons un ensemble de modules basés sur la plateforme MadKit
The work presented in this PhD thesis is concerned with the development of a framework for Holonic MultiAgent Systems. This type of systems consists in self-similar structures called holons. A set of holons may be seen, depending on the level of observation, as a unique entity or as a group of holons in interaction. In order to conceive a generic and modular modeling framework, we use an organizational approach. We define then the behavior of the frame work entities in terms of roles and their interactions. The framework is concerned with the modeling and representation of three important aspects of a Holonic MAS. Holon Structure and Management : This part of the framework considers how the members organize and manage the super-holon. It offers a specific organization whose roles define the status of the member from the super-holon's point of view. Goal-Dependent Interactions : In order to achieve the goals/tasks of the super-holon, the members must interact and coordinate their actions. These goal-dependent behaviors are called Internal Organizations and our framework also offers means to model these aspects of the super-holons functioning. Dynamics : Dynamics are inherent characteristics of MAS. The framework considers in particular two of the most attractive characteristics of Holonic MAS: Merging (Creating and Joining a super-holon) and Self-Organization. Each organization is modeled using the Role-Interaction-Organization (RIO) Model. This model offers a formal specification of roles that enables the validation and verification of the model. We have formally specified the framework. Based on this formalization we were able to prove important properties concerning the self-organization of the system. We propose some guidelines based upon this framework for the analysis and design of Complex Systems. Two applications illustrate the concepts presented. The first uses the framework to the Adaptive Meshing Problem applied to the dimensioning of radiomobile networks. It illustrates the refinement of a self-organization module and formal specification. The second presents the use of holonic MAS for the simulation of an important industrial plant. Multiple holarchies are used to capture the interaction between the production and traffic inside the plant. In order to implement these concepts we propose a set of modules based on the MadKit platform
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Byrd, Mark Steven. "Representations of SU(3) and geometric phases for three-state systems /." Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.

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18

Bohnet, Doris Verfasser], and Christian [Akademischer Betreuer] [Bonatti. "Partially hyperbolic systems with a compact center foliation with finite holonomy / Doris Bohnet. Betreuer: Christian Bonatti." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2011. http://d-nb.info/1020466790/34.

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19

Chu, Xing. "Commande distribuée, en poursuite, d'un système multi-robots non holonomes en formation." Thesis, Ecole centrale de Lille, 2017. http://www.theses.fr/2017ECLI0035/document.

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L’objectif principal de cette thèse est d’étudier le problème du contrôle de suivi distribué pour les systèmes de formation de multi-robots à contrainte non holonomique. Ce contrôle vise à entrainer une équipe de robots mobile de type monocycle pour former une configuration de formation désirée avec son centroïde se déplaçant avec une autre trajectoire de référence dynamique et pouvant être spécifié par le leader virtuel ou humain. Le problème du contrôle de suivi a été résolu au cours de cette thèse en développant divers contrôleurs distribués pratiques avec la considération d’un taux de convergence plus rapide, une précision de contrôle plus élevée, une robustesse plus forte, une estimation du temps de convergence explicite et indépendante et moins de coût de communication et de consommation d’énergie. Dans la première partie de la thèse nous étudions d’abord au niveau du chapitre 2 la stabilité à temps fini pour les systèmes de formation de multi-robots. Une nouvelle classe de contrôleur à temps fini est proposée dans le chapitre 3, également appelé contrôleur à temps fixe. Nous étudions les systèmes dynamiques de suivi de formation de multi-robots non holonomiques dans le chapitre 4. Dans la deuxième partie, nous étudions d'abord le mécanisme de communication et de contrôle déclenché par l'événement sur les systèmes de suivi de la formation de multi-robots non-holonomes au chapitre 5. De plus, afin de développer un schéma d'implémentation numérique, nous proposons une autre classe de contrôleurs périodiques déclenchés par un événement basé sur un observateur à temps fixe dans le chapitre 6
The main aim of this thesis is to study the distributed tracking control problem for the multi-robot formation systems with nonholonomic constraint, of which the control objective it to drive a team of unicycle-type mobile robots to form one desired formation configuration with its centroid moving along with another dynamic reference trajectory, which can be specified by the virtual leader or human. We consider several problems in this point, ranging from finite-time stability andfixed-time stability, event-triggered communication and control mechanism, kinematics and dynamics, continuous-time systems and hybrid systems. The tracking control problem has been solved in this thesis via developing diverse practical distributed controller with the consideration of faster convergence rate, higher control accuracy, stronger robustness, explicit and independent convergence time estimate, less communication cost and energy consumption.In the first part of the thesis, we first study the finite-time stability for the multi-robot formation systems in Chapter 2. To improve the pior results, a novel class of finite-time controller is further proposed in Chapter 3, which is also called fixed-time controller. The dynamics of nonholonomic multi-robot formation systems is considered in Chapter 4. In the second part, we first investigate the event-triggered communication and control mechanism on the nonholonomic multi-robot formation tracking systems in Chapter 5. Moreover, in order to develop a digital implement scheme, we propose another class of periodic event-triggered controller based on fixed-time observer in Chapter 6
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20

Pasquotti, Maura. "Topics on Optimization Strategies for Constrained Mechanical Systems." Doctoral thesis, Università degli studi di Padova, 2008. http://hdl.handle.net/11577/3425582.

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In the first part of the work we analyze the problem of optimal control of a vehicle along a preassigned trajectory. The vehicle system is studied and simplified in order to obtain a computationally tractable model, which still presents the main characteristics of the real vehicle. The control algorithm, based on MPC techniques, is then explained and its effectiveness is proved through simulation results. The “minimum lap time problem” is afterward considered, which can be considered as an evolution of the trajectory tracking problem; its analysis is presented and is followed by the developed solution, based on pseudospectral methods. In the second part of the thesis the problem of control of underactuated mechanical systems is discussed. The nonholonomic system classically called “rolling disk” is considered as test case; it is a wheel with punctiform contact surface that can roll on the plane without sliding laterally. Differently from the literature we consider the torque as the unique control input signal. This system is modeled through the Lagrangian formalism and then the control strategy, based on backstepping and receding horizon techniques, is shown and proved to be effective.
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21

Small, Scott Joseph. "Runge-Kutta type methods for differential-algebraic equations in mechanics." Diss., University of Iowa, 2011. https://ir.uiowa.edu/etd/1082.

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Differential-algebraic equations (DAEs) consist of mixed systems of ordinary differential equations (ODEs) coupled with linear or nonlinear equations. Such systems may be viewed as ODEs with integral curves lying in a manifold. DAEs appear frequently in applications such as classical mechanics and electrical circuits. This thesis concentrates on systems of index 2, originally index 3, and mixed index 2 and 3. Fast and efficient numerical solvers for DAEs are highly desirable for finding solutions. We focus primarily on the class of Gauss-Lobatto SPARK methods. However, we also introduce an extension to methods proposed by Murua for solving index 2 systems to systems of mixed index 2 and 3. An analysis of these methods is also presented in this thesis. We examine the existence and uniqueness of the proposed numerical solutions, the influence of perturbations, and the local error and global convergence of the methods. When applied to index 2 DAEs, SPARK methods are shown to be equivalent to a class of collocation type methods. When applied to originally index 3 and mixed index 2 and 3 DAEs, they are equivalent to a class of discontinuous collocation methods. Using these equivalences, (s,s)--Gauss-Lobatto SPARK methods can be shown to be superconvergent of order 2s. Symplectic SPARK methods applied to Hamiltonian systems with holonomic constraints preserve well the total energy of the system. This follows from a backward error analysis approach. SPARK methods and our proposed EMPRK methods are shown to be Lagrange-d'Alembert integrators. This thesis also presents some numerical results for Gauss-Lobatto SPARK and EMPRK methods. A few problems from mechanics are considered.
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Mettin, Uwe. "Principles for planning and analyzing motions of underactuated mechanical systems and redundant manipulators." Doctoral thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-30024.

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Motion planning and control synthesis are challenging problems for underactuated mechanical systems due to the presence of passive (non-actuated) degrees of freedom. For those systems that are additionally not feedback linearizable and with unstable internal dynamics there are no generic methods for planning trajectories and their feedback stabilization. For fully actuated mechanical systems, on the other hand, there are standard tools that provide a tractable solution. Still, the problem of generating efficient and optimal trajectories is nontrivial due to actuator limitations and motion-dependent velocity and acceleration constraints that are typically present. It is especially challenging for manipulators with kinematic redundancy. A generic approach for solving the above-mentioned problems is described in this work. We explicitly use the geometry of the state space of the mechanical system so that a synchronization of the generalized coordinates can be found in terms of geometric relations along the target motion with respect to a path coordinate. Hence, the time evolution of the state variables that corresponds to the target motion is determined by the system dynamics constrained to these geometrical relations, known as virtual holonomic constraints. Following such a reduction for underactuated mechanical systems, we arrive at integrable second-order dynamics associated with the passive degrees of freedom. Solutions of this reduced dynamics, together with the geometric relations, can be interpreted as a motion generator for the full system. For fully actuated mechanical systems the virtually constrained dynamics provides a tractable way of shaping admissible trajectories. Once a feasible target motion is found and the corresponding virtual holonomic constraints are known, we can describe dynamics transversal to the orbit in the state space and analytically compute a transverse linearization. This results in a linear time-varying control system that allows us to use linear control theory for achieving orbital stabilization of the nonlinear mechanical system as well as to conduct system analysis in the vicinity of the motion. The approach is applicable to continuous-time and impulsive mechanical systems irrespective of the degree of underactuation. The main contributions of this thesis are analysis of human movement regarding a nominal behavior for repetitive tasks, gait synthesis and stabilization for dynamic walking robots, and description of a numerical procedure for generating and stabilizing efficient trajectories for kinematically redundant manipulators.
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La, Hera Pedro. "Underactuated mechanical systems : Contributions to trajectory planning, analysis, and control." Doctoral thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-39719.

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Nature and its variety of motion forms have inspired new robot designs with inherentunderactuated dynamics. The fundamental characteristic of these controlled mechanicalsystems, called underactuated, is to have the number of actuators less than the number ofdegrees of freedom. The absence of full actuation brings challenges to planning feasibletrajectories and designing controllers. This is in contrast to classical fully-actuated robots.A particular problem that arises upon study of such systems is that of generating periodicmotions, which can be seen in various natural actions such as walking, running,hopping, dribbling a ball, etc. It is assumed that dynamics can be modeled by a classicalset of second-order nonlinear differential equations with impulse effects describing possibleinstantaneous impacts, such as the collision of the foot with the ground at heel strikein a walking gait. Hence, we arrive at creating periodic solutions in underactuated Euler-Lagrange systems with or without impulse effects. However, in the qualitative theory ofnonlinear dynamical systems, the problem of verifying existence of periodic trajectoriesis a rather nontrivial subject.The aim of this work is to propose systematic procedures to plan such motions and ananalytical technique to design orbitally stabilizing feedback controllers. We analyze andexemplify both cases, when the robotmodel is described just by continuous dynamics, andwhen continuous dynamics is interrupted from time to time by state-dependent updates.For trajectory planning, systems with one or two passive links are considered, forwhich conditions are derived to achieve periodicmotions by encoding synchronizedmovementsof all the degrees of freedom. For controller design we use an explicit form tolinearize dynamics transverse to the motion. This computation is valid for an arbitrarydegree of under-actuation. The linear system obtained, called transverse linearization, isused to analyze local properties in a vicinity of the motion, and also to design feedbackcontrollers. The theoretical background of these methods is presented, and developedin detail for some particular examples. They include the generation of oscillations forinverted pendulums, the analysis of human movements by captured motion data, and asystematic gait synthesis approach for a three-link biped walker with one actuator.
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Braconnier, Jean-Baptiste. "Maintien de l'intégrité de robots mobiles en milieux naturels." Thesis, Clermont-Ferrand 2, 2016. http://www.theses.fr/2016CLF22667/document.

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La problématique étudiée dans cette thèse concerne le maintien de l’intégrité de robots mobiles en milieux naturels. L’objectif est de fournir des lois de commande permettant de garantir l’intégrité d’un véhicule lors de déplacements autonomes en milieux naturels à vitesse élevée (5 à 7 m.s -1 ) et plus particulièrement dans le cadre de l’agriculture de précision. L’intégrité s’entend ici au sens large. En effet, l’asservissement des déplacements d’un robot mobile peut générer des consignes nuisant à son intégrité physique, ou à la réalisation de sa tâche (renversement, tête-à-queue, stabilité des commandes, maintien de la précision, etc.). De plus, le déplacement en milieux naturels amène des problématiques liées notamment à des conditions d’adhérence variables et relativement faibles (d’autant plus que la vitesse du véhicule est élevée), ce qui se traduit par de forts glissements des roues sur le sol, ou encore à des géométries de terrains non traversables par le robot. Aussi, cette thèse vise à déterminer en temps réel l’espace de stabilité en terme de commandes admissibles permettant de modérer les actions du robot. Après une présentation des modélisations existantes, et des observateurs permettant l’exploitation de ces modélisations pour la mise en place de loi de commande prédictive en braquage pour le suivi de trajectoire, une nouvelle méthode d’estimation des glissements basé sur une observation cinématique est proposée. Celle-ci permet de répondre aux problématiques de vitesse variable (et notamment du passage de la vitesse par des valeurs nulles) du véhicule et d’observation lors d’un déplacement sans trajectoire de référence. Ce nouvel observateur est primordial pour la suite des développements de cette thèse, puisque la suite des travaux s’intéresse à la modulation de la vitesse du véhicule. Ainsi, dans la suite des travaux, deux lois de commande prédictives agissant sur la vitesse du véhicule ont été mises en place. La première apporte une solution à la problématique de la saturation des actionneurs en braquage, lorsque la vitesse ou les glissements rendent la trajectoire à suivre inadmissible vis-à-vis des capacités physiques du véhicule. La deuxième répond à la problématique de la garantie de la précision du suivi de trajectoire (maintien du véhicule dans un couloir de déplacement). Dans les deux cas la stratégie de commande est similaire : on prédit l’état futur du véhicule en fonction de ses conditions d’évolution actuelle et de conditions d’évolutions futures simulées (obtenues grâce à la simulation de l’évolution d’un modèle dynamique du véhicule) afin de déterminer la valeur de la vitesse optimale pour que les variables cibles (dans un cas la valeur du braquage et dans l’autre l’écart à la trajectoire) respectent les conditions imposées (non-dépassement d’une valeur cible). Les résultats présentés dans ce mémoire ont été réalisés soit en simulations, soit en conditions réelles sur des plateformes robotiques. Il en découle que les algorithmes proposés permettent dans un cas de réduire la vitesse du véhicule pour éviter la saturation du braquage et donc les phénomènes de sur et sous virage qui en découlerait et donc permet de conserver la commandabilité du véhicule. Et dans l’autre cas de garantir que l’écart à la trajectoire reste sous une valeur cible
This thesis focused on the issue of the preseving of the integrity of mobile robots in off-road conditions. The objective is to provide control laws to guarantee the integrity of a vehicle during autonomous displacements in natural environments at high speed (5 to 7 m.s -1 ) and more particularly in The framework of precision farming. Integrity is here understood in the broad sense. Indeed, control of the movements of a mobile robot can generate orders that affect its physical integrity, or restrains the achievement of its task (rollover, spin, control stability, maintaining accuracy , etc.). Moreover, displacement in natural environments leads to problems linked in particular to relatively variable and relatively low adhesion conditions (especially since the speed of the vehicle is high), which results in strong sliding of wheels on the ground, or to ground geometries that can not be crossed by the robot. This thesis aims to determine in real time the stability space in terms of permissible controls allowing to moderate the actions of the robot. After a presentation of the existing modelings and observers that allow the use of these modelizations for the implementation of predictive control law for trajectory tracking, a new method of estimation of side-slip angles based on a kinematic observation is proposed. It permit to address the problem of variable speed of the vehicle (and in particular the case of zero values) and also to allow the observation during a displacement without reference trajectory. This new observer is essential for the further development of this thesis, since the rest of the work is concerned with the modulation of the speed of the vehicle. So, in the further work, two predictive control laws acting on the speed of the vehicle have been set up. The first one provides a solution to the problem of the saturation of steering actuators, when the speed or side-slip angles make the trajectory inadmissible to follow with respect to the physical capacities of the vehicle. The second one adress the problem of guaranteeing the accuracy of trajectory tracking (keeping the vehicle in a corridor of displacement). In both cases, the control strategy is similar: the future state of the vehicle is predicted according to the current conditions of evolution and the simulated one for the future evolution (obtained by simulating the evolution of dynamics models of the vehicle) in order to determine the value of the optimum speed so that the target variables (in one case the value of the steering and in the other the lateral deviation from the trajectory) comply with the imposed conditions (not exceeding a target value). The results presented in this thesis were realized either in simulations or in real conditions on robotic platforms. It follows that the proposed algorithms make it possible : in one case to reduce the speed of the vehicle in order to avoid the saturation of the steering actuator and therefore the resulting over and under steering phenomena and thus make it possible to preserve the vehicle’s controllability. And in the other case, to ensure that the lateral deviation from the trajectory remains below a target value
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25

Arechavaleta, Servin Gustavo. "An optimality principle governing human walking." Toulouse, INSA, 2007. http://eprint.insa-toulouse.fr/archive/00000193/.

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This work seeks to analyze human walking at the trajectory planning level from an optimal control perspective. Our approach emphasizes the close relationship between the geometric shape of human locomotion in goal-directed movements and the simplified kinematic model of a wheeled mobile robot. This kind of system has been extensively studied in robotics community. From a kinematic perspective, the characteristic of this wheeled robot is the nonholonomic constraint of the wheels on the floor, which forces the vehicle to move tangentially to its main axis. In the case of human walking, the observation indicates that the direction of the motion is given by the direction of the body (due to some anatomical, mechanical body constraints. . . ). This coupling between the direction q and the position (x,y) of the body can be summarized by tanq = ˙ y ˙ x. It is known that this differential equation defines a non integrable 2- dimensional distribution in the 3-dimensional manifold R2×S1 gathering all the configurations (x,y,q). The controls of a vehicle are usually the linear velocity (via the accelerator and the brake) and the angular velocity (via the steering wheel). The first question addressed in this study can be roughly formulated as : where is the “steering wheel” of the human body located ? It appears that the torso can be considered as a kind of a steering wheel that steers the human body. This model has been validated on a database of 1,560 trajectories recorded from seven subjects. In the second part we address the following question : among all possible trajectories reaching a given position and direction, the subject has chosen one. Why ? The central idea to understand the shape of trajectories has been to relate this problem to an optimal control scheme : the trajectory is chosen according to some optimization principle. The subjects being viewed as a controlled system, we tried to identify several criteria that could be optimized. Is it the time to perform the trajectory ? the length of the path ? the minimum jerk along the path ?. . . We argue that the time derivative of the curvature of the locomotor trajectories is minimized. We show that the human locomotor trajectories are well approximated by the geodesics of a differential system minimizing the L2 norm of the control. Such geodesics are made of arcs of clothoids. The clothoid is a curve whose curvature grows with the distance from the origin. The accuracy of the model is supported by the fact that 90 percent of trajectories are approximated with an average error < 10cm. In the last part of this work we provide the partition of the 3-dimensional configuration space in cells : 2 points belong to a same cell if and only if they are reachable from the origin by a path of the same type. Such a decomposition is known as the synthesis of the optimal control problem. Most of the time when the target changes slightly the optimal trajectories change slightly. However, some singularities appear at some critical frontiers between cells. It is noticeable that they correspond to the strategy change for the walking subjects. This fundamental result is another poof of the locomotion model we have proposed
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26

Roithmayr, Carlos. "Relating constrained motion to force through Newton's second law." Diss., Available online, Georgia Institute of Technology, 2007, 2007. http://etd.gatech.edu/theses/available/etd-03302007-125659/.

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Thesis (Ph. D.)--Aerospace Engineering, Georgia Institute of Technology, 2007.
Bauchau, Olivier, Committee Member ; Hodges, Dewey, Committee Chair ; Singhose, William, Committee Member ; Costello, Mark, Committee Member ; Flannery, Raymond, Committee Member.
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27

Tchappi, haman Igor. "Dynamic Multilevel and Holonic Model for the Simulation of a Large-Scale Complex System with Spatial Environment : Application to Road Traffic Simulation." Thesis, Bourgogne Franche-Comté, 2020. http://www.theses.fr/2020UBFCA004.

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De nos jours, avec l’émergence d’objets et de voitures connectés, les systèmes de trafic routier deviennent de plus en plus complexes et présentent des comportements hiérarchiques à plusieurs niveaux de détail. L'approche de modélisation multiniveaux est une approche appropriée pour représenter le trafic sous plusieurs perspectives. Les modèles multiniveaux constituent également une approche appropriée pour modéliser des systèmes complexes à grande échelle comme le trafic routier. Cependant, la plupart des modèles multiniveaux de trafic proposés dans la littérature sont statiques car ils utilisent un ensemble de niveaux de détail prédéfinis et ces représentations ne peuvent pas commuter pendant la simulation. De plus ces modèles multiniveaux considèrent généralement seulement deux niveaux de détail. Très peu de travaux se sont intéressés à la modélisation dynamique multiniveau de trafic.Cette thèse propose un modèle holonique multiniveau et dynamique du trafic à grande échelle.La commutation dynamique des niveaux de détail lors de l’exécution de la simulation permet d’adapter le modèle aux contraintes liées à la qualité des résultats ou aux ressources de calcul disponibles.La proposition étend l'algorithme DBSCAN dans le contexte des systèmes multi-agents holoniques. De plus, une méthodologie permettant la commutation dynamique entre les différents niveaux de détail est proposée. Des indicateurs multiniveaux basés sur l'écart type sont aussi proposés afin d'évaluer la cohérence des résultats de la simulation
Nowadays, with the emergence of connected objects and cars, road traffic systems become more and more complex and exhibit hierarchical behaviours at several levels of detail. The multilevel modeling approach is an appropriate approach to represent traffic from several perspectives. Multilevel models are also an appropriate approach to model large-scale complex systems such as road traffic. However, most of the multilevel models of traffic proposed in the literature are static because they use a set of predefined levels of detail and these representations cannot change during simulation. Moreover, these multilevel models generally consider only two levels of detail. Few works have been interested on the dynamic multilevel traffic modeling.This thesis proposes a holonic multilevel and dynamic traffic model for large scale traffic systems. The dynamic switching of the levels of detail during the execution of the simulation allows to adapt the model to the constraints related to the quality of the results or to the available computing resources.The proposal extends the DBSCAN algorithm in the context of holonic multi-agent systems. In addition, a methodology allowing a dynamic transition between the different levels of detail is proposed. Multilevel indicators based on standard deviation are also proposed in order to assess the consistency of the simulation results
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Bott, M. P. "A new, robust, and generic method for the quick creation of smooth paths and near time-optimal path tracking." Thesis, University of St Andrews, 2011. http://hdl.handle.net/10023/2095.

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Robotics has been the subject of academic study from as early as 1948. For much of this time, study has focused on very specific applications in very well controlled environments. For example, the first commercial robots (1961) were introduced in order to improve the efficiency of production lines. The tasks undertaken by these robots were simple, and all that was required of a control algorithm was speed, repetitiveness and reliability in these environments. Now however, robots are being used to move around autonomously in increasingly unpredictable environments, and the need for robotic control algorithms that can successfully react to such conditions is ever increasing. In addition to this there is an ever-increasing array of robots available, the control algorithms for which are often incompatible. This can result in extensive redesign and large sections of code being re-written for use on different architectures. The thesis presented here is that a new generic approach can be created that provides robust high quality smooth paths and time-optimal path tracking to substantially increase applicability and efficiency of autonomous motion plans. The control system developed to support this thesis is capable of producing high quality smooth paths, and following these paths to a high level of accuracy in a robust and near time-optimal manner. The system can control a variety of robots in environments that contain 2D obstacles of various shapes and sizes. The system is also resilient to sensor error, spatial drift, and wheel-slip. In achieving the above, this system provides previously unavailable functionality by generically creating and tracking high quality paths so that only minor and clear adjustments are required between different robots and also be being capable of operating in environments that contain high levels of perturbation. The system is comprised of five separate novel component algorithms in order to cater for five different motion challenges facing modern robots. Each algorithm provides guaranteed functionality that has previously been unavailable in respect to its challenges. The challenges are: high quality smooth movement to reach n-dimensional goals in regions without obstacles, the navigation of 2D obstacles with guaranteed completeness, high quality smooth movement for ground robots carrying out 2D obstacle navigation, near time-optimal path tracking, and finally, effective wheel-slip detection and compensation. In meeting these challenges the algorithms have tackled adherence to non-holonomic constraints, applicability to a wide range of robots and tasks, fast real-time creation of paths and controls, sensor error compensation, and compensation for perturbation. This thesis presents each of the above algorithms individually. It is shown that existing methods are unable to produce the results provided by this thesis, before detailing the operation of each algorithm. The methodology employed is varied in accordance with each of the five core challenges. However, a common element of methodology throughout the thesis is that of gradient descent within a new type of potential field, which is dynamic and capable of the simultaneous creation of high-quality paths and the controls required to execute them. By relating global to local considerations through subgoals, this methodology (combined with other elements) is shown to be fully capable of achieving the aims of the thesis. It is concluded that the produced system represents a novel and significant contribution as there is no other system (to the author’s knowledge) that provides all of the functionality given. For each component algorithm there are many control systems that provide one or more of its features, but none that are capable of all of the features. Applications for this work are wide ranging as it is comprised of five component algorithms each applicable in their own right. For example, high quality smooth paths may be created and followed in any dimensionality of space if time optimality and obstacle avoidance are not required. Broadly speaking, and in summary, applications are to ground-based robotics in the areas of smooth path planning, time optimal travel, and compensation for unpredictable perturbation.
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Adoum, Ahmat Fadil. "Proposition d’une architecture de surveillance holonique pour l’aide à la maintenance proactive d’une flotte de systèmes mobiles : application au domaine ferroviaire." Thesis, Valenciennes, 2019. http://www.theses.fr/2019VALE0001/document.

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La maintenance de flottes de systèmes mobiles dans le monde du transport et de la logistique revêt de nos jours une importance croissante de par l’augmentation des attentes des exploitants et opérateurs en termes de sécurité, de fiabilité, de suivi, de diagnostic et de maintenance de ces systèmes. Dans ce contexte, Les mainteneurs des flottes doivent souvent faire face à d'énormes quantités de données brutes, informations et événements de surveillance liés aux contexte de leurs systèmes. De plus, ces événements, données et informations manquent souvent de précision et sont souvent contradictoires ou obsolètes. Enfin, le degré d'urgence des décisions de maintenance est rarement pris en compte. Ce travail est consacré à la proposition et à la mise au point d’une architecture de surveillance pour l’aide à la maintenance d’une flotte de systèmes mobiles. Cette architecture, appelée EMH², est destinée à faciliter le diagnostic et le suivi de ce type de flotte. Elle est construite sur les principes holoniques, des plus bas (capteurs) aux plus hauts niveaux (ensemble d’une flotte de systèmes mobiles). Elle se base également sur une standardisation des événements traités afin de traiter les données de manière générique. Cette architecture, indépendante des types de systèmes surveillés et de leur niveau hiérarchique, peut devenir l'épine dorsale d’une stratégie efficace de maintenance proactive d’une flotte. Une méthodologie de déploiement est ainsi proposée. Une étude en simulation et une application sur une flotte de 10 trains actuellement en service est présentée
The maintenance of mobile systems fleets in the world of transport and logistics is of increasing importance today due to the increasing expectations of operators in terms of safety, reliability, monitoring, diagnosis and maintenance of these systems. In this context, fleet maintainers often have to deal with huge amounts of raw data, information and monitoring events related to the context of their systems. Moreover, these events, data and information are often lack precision and often contradictory or obsolete. Finally, the urgency of maintenance decisions is rarely taken into account. This work is devoted to the proposal and the development of a monitoring architecture to help maintain a fleet of mobile systems. This architecture, called EMH², is intended to facilitate the diagnosis and monitoring of this type of fleet. It is built on holonic principles, from the lowest (sensors) to the highest levels (a whole fleet of mobile systems). It is also based on a standardization of processed events in order to process the data generically. This architecture, independent of the types of systems monitored and their hierarchical level, can become the backbone of an effective strategy for proactive fleet maintenance. A deployment methodology is thus proposed. A simulation study and an application on a fleet of 10 trains currently in service is presented
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30

Alamir, Mazen. "Contributions à l'étude de la commande optimale à horizon fuyant des systèmes non linéaires." Grenoble INPG, 1995. http://www.theses.fr/1995INPG0135.

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Dans ce travail, plusieurs aspects de la commande optimale à horizon fuyant sont considérés. Selon cette stratégie de commande, un problème d'optimisation en boucle ouverte est d'abord résolu sur un horizon donné; la première commande de la séquence optimale résultante est seule appliquée au système et le tout est recommencé au pas suivant, ceci pose le problème de la stabilité du schéma obtenu. Dans une première partie, des conditions suffisantes de stabilité sont proposées pour les différentes formulations possibles (Horizon fini avec contrainte sur l'état final, horizon infini sans contrainte finale, horizon fini sans contrainte finale). Dans la suite, une loi de commande inspirée du principe de l'horizon fuyant est proposée pour les systèmes discrets non linéaires définis avec des incertitudes additives non structurées. Cette loi est fondée sur l'utilisation des problèmes d'optimisations avec contraintes finales d'inégalité dans lesquels la longueur de l'horizon est aussi une variable d'optimisation. La robustesse de la loi de commande périodique ainsi obtenue est alors discutée. La mise en œuvre de la commande optimale à horizon fuyant en temps réel dans le cas général reste un problème sérieux. Dans la troisième partie de ce travail, nous caractérisons une classe particulière de systèmes continus non linéaires pour lesquels la stabilisation par retour d'état peut être résolue au moyen d'une formulation fondée sur les principes de l'horizon fuyant où le problème d'optimisation est linéaire quadratique d'où une mise en œuvre en temps réel possible
In this work, several aspects of the receding horizon control strategy are discussed. First of all, some suffisant conditions for the stability of the closed loop system are proposed for different possible formulations (finite or infinite prediction horizon, with or without final constraint on the state). In a second part, a robust stabilizing feedback strategy is proposed to stabilize uncertain discrete-time nonlinear systems defined with additive unmatched uncertainties. The feedback law is periodic and is based on the use of optimization problems with final inequality constraints. Finally, a special class of continuous nonlinear systems is characterized for which a real time implementation of the receding horizon principle is possible through a linear quadratic optimization problem formulation
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31

Barbosa, José. "Proposition d’une architecture holonique auto-organisée et évolutive pour le pilotage des systèmes de production." Thesis, Valenciennes, 2015. http://www.theses.fr/2015VALE0008/document.

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Le monde des entreprises est profondément soumis à un ensemble de contraintes toujours plus exigeantes provenant d’une part des clients, exigeant des produits plus personnalisables, de qualité supérieure et à faible coût, et d’autre part des aléas internes auxentreprises, comprenant les pannes machines, les défaillances humaines, la fluctuation de la demande, les fréquentes variations de production. Cette thèse propose une architecture de contrôle de systèmes de production, basée sur les principes holoniques développées dans l’architecture ADACOR (ADAptive holonic COntrol aRchitecture), et l’étendant en s’inspirant des théories de l’évolution et en utilisant des mécanismes d’auto-organisation. L’utilisation des théories de l’évolution enrichit l’architecture de contrôle en permettant l’évolution de deux manières distinctes, en réponse au type et au degré de la perturbation apparue. Le premier mode d’adaptation, appelé auto-organisation comportementale, permet à chaque entité qui compose le système d’adapter dynamiquement leur comportement interne, gérant de cette façon de petites perturbations. Le second mode, nommé auto-organisation structurelle, traite de plus grandes perturbations, en permettant aux entités du système de ré-organiser leurs relations, et par conséquent modifier structurellement le système. L’architecture holonique auto-organisée de contrôle de systèmes de production proposée dans cette thèse a été validée sur une cellule de production flexible AIP-PRIMECA. Les résultats ont montré une amélioration des indicateurs clés de performance par rapport aux architectures de contrôle hiérarchiques et hétérarchiques
The manufacturing world is being deeply challenged with a set of ever demanding constraints where from one side, the costumers are requiring products to be more customizable, with higher quality at lower prices, and on other side, companies have to deal on a daily basis with internal disturbances that range from machine breakdown to worker absence and from demand fluctuation to frequent production changes. This dissertation proposes a manufacturing control architecture, following the holonic principles developed in the ADAptive holonic COntrol aRchitecture (ADACOR) and extending it taking inspiration in evolutionary theories and making use of self- organization mechanisms. The use of evolutionary theories enrich the proposed control architecture by allowing evolution in two distinct ways, responding accordingly to the type and degree of the disturbance that appears. The first component, named behavioural self- organization, allows each system’s entity to dynamically adapt its internal behaviour, addressing small disturbances. The second component, named structural self-organization, addresses bigger disturbances by allowing the system entities to re-arrange their rela- tionships, and consequently changing the system in a structural manner. The proposed self-organized holonic manufacturing control architecture was validated at a AIP-PRIMECA flexible manufacturing cell. The achieved experimental results have also shown an improvement of the key performance indicators over the hierarchical and heterarchical control architecture
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32

Bouffaron, Fabien. "Co-spécification système exécutable basée sur des modèles : application à la conduite interactive d’un procédé industriel critique." Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0001/document.

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Dans la mesure où un système est un ensemble d'éléments en interaction, la difficulté pour un ingénieur système est de guider l’architecture d'un modèle « total » du système en tant qu'ensemble de modèles « locaux » d’ingénieries interdisciplinaires en interaction. Les travaux présentés dans ce mémoire s’intéressent plus précisément à la nature heuristique, spécifiante et exécutable de cette relation « totale » de couplage afin de construire un modèle virtuel du système à faire. La perspective holonique retenue permet de considérer cette relation de couplage de façon descriptive du TOUT et prescriptive de chacune des PARTIES aussi bien en regard de la situation-système à percevoir que des constitutifs-système à architecturer. Ainsi, nous avons revisité cette relation en tant que processus itératif, récursif et collaboratif de co-spécification-système visant à supporter la requête de connaissances auprès de chacune des ingénieries spécialistes délivrant en retour les modèles constitutifs satisfaisant des exigences systèmes. Notre environnement de co-modélisation-système se compose alors d’un ensemble d’environnements élémentaires de modélisation de constituants-système, avec pour objectif de préserver les outils, méthodes et processus de travail de chacune des parties prenantes. La modélisation au niveau système s’appuie sur le langage de modélisation « SysML » pour architecturer l’ensemble des connaissances. La vérification et la validation système s’effectue par co-exécution de modèles autour d’un bus de co-simulation, y compris in-situ avec la plate-forme d’expérimentation CISPI du projet SAFETECH du CRAN constituant notre cas d’application
Insofar as a system is a set of interacting elements, the difficulty for a system engineer is to guide the whole model architecture of a system as a set of interdisciplinary engineering part models interacting. The works presented in this thesis are specifically interested in the heuristic, specifying and executable nature of this whole relationship coupling to design a virtual model of the system-of-interest. The holonic perspectives allows us to consider this coupling relationship as descriptive of a WHOLE (H) and prescriptive of each parts as well in regards to system situation to perceive, as system-elements to architect. In this sense, we revisit this relation as an iterative, recursive and collaborative process of system co-specification to the quest of knowledge with each specialist engineering delivering constitutive models satisfying basic requirements. Our system co-modelling environment is itself composed of a set of system-components modelling environment, with the stated objective to preserve tools, methods and works of each stakeholders in order to facilitate the expression of their skills. The modelling at a system level is based on the system modelling language (SysML) to architecture the set of knowledge. Verification and validation are performed by co-execution of models around a co-simulation bus, including CISPI platform of SAFETECH project of CRAN constituting our case study
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33

Lohéac, Jérôme. "Contrôle en temps optimal et nage à bas nombre de Reynolds." Phd thesis, Université de Lorraine, 2012. http://tel.archives-ouvertes.fr/tel-00801240.

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Cette thèse est divisée en deux parties, le fil directeur étant la contrôlabilité en temps optimal. Dans la première partie, après un rappel du principe du maximum de Pontryagin dans le cas des systèmes de dimension finie, nous mettrons en œuvre ce principe sur le cas d'un intégrateur non-holonome connu sous le nom de système de Brockett pour lequel nous imposons des contraintes sur l'état. La difficulté de cette étude provient du fait que l'on considère un problème de contrôle avec des contraintes sur l'état. Après cet exemple, nous nous intéressons à une extension du principe du maximum de Pontryagin au cas des systèmes de dimension infinie. Plus précisément, l'extension que nous considérons s'applique au cas de systèmes exactement contrôlables en tout temps. Typiquement, ce résultat s'applique à l'équation de Schrödinger avec contrôle interne. Pour de tels systèmes, sous une condition de contrôlabilité approchée, depuis un ensemble de temps non négligeable, nous montrons l'existence d'un contrôle bang-bang. Dans la seconde partie, nous étudions le problème de la nage à bas nombre de Reynolds. Une modélisation physique convenable nous permet de le formaliser comme un problème de contrôle. Nous obtenons alors un résultat de contrôlabilité sur ce problème. Plus précisément, nous montrons que quelque soit la forme du nageur, celui-ci peut se déformer légèrement pour suivre une trajectoire imposée. Nous étudions ensuite le cas d'un nageur à symétrie axiale. Les résultats de la première partie permettent alors la recherche d'un contrôle en temps optimal.
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34

Xu, Ying-Lin, and 許應麟. "A dynamic analysis of non-holonomic constraint rigid body system." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/04058865542816357909.

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35

Hsu, Ying-Lin, and 許應麟. "A dynamic analysis of non-holonomic constraint rigid body system." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/46205334916940297152.

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碩士
國立臺灣大學
應用力學研究所
85
This paper follows the theories developed by C.O. Chang and V.C. Wang in 1996. They combined Gauss'' Principle of Least Constrain with State Transform to rapidly derive the minimum set of the first order state equations. It is named Constraint-Free State Equations. We apply this method to multi-rigid body nonholonomic constraint in this paper. First, for a double-wheel-roll system, we discuss three situations: non-assigned constraint, assigned track, and assign both track and velocity. Second, for a four-wheel-roll system, we mainly discuss two situations: non-assigned constraint and assigned track. From the above two cases, we conclude that it is a good method for deriving the Constrant-Free State Equations for the systems. However, there are some problems in system control should be solved, and more diecussions will be needed. Hopefully, this paper can provide some easy examples to those who are interesting in Nonholonomic Dynamics. By reading the content, they can understand more and more about this field.
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36

Cheng, Kuang-Chih, and 鄭光志. "Numerical solutions for DAE and it's applications in non-holonomic system." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/23428666919088350039.

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碩士
國立臺灣海洋大學
通訊與導航工程系
95
Abstract In this thesis, we propose a numerical method for solving the non-holonomic systems by utilizing the differential-algebraic equations (DAE's). In the field of mechanics, the non-holonomic systems are commonly seen, which have the non-integrable property, that is they can not be integrated exactly to obtain an analytic solution. Therefore, in order to have a fully understand of the properties of the solution trajectories of the non-holonomic systems, it is necessary that the numerical method is adopted. In the present dissertation, we use DAE’s to analyze the systems with non-holonomic constraints. Firstly, the non-holonomic systems are reformulated as DAE’s, and then the DAE’s are approximated by Pad´e series in order to be solved by the so-called computer algebra method. The main advantage the computer algebra method lies in that the mathematical concept can be presented much more intuitively.
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37

Conceição, Rafael Tiago Neto Salvado Martins da. "Desenvolvimento de um sensor de docagem com aplicação em robôs holonómicos." Master's thesis, 2015. http://hdl.handle.net/10316/38990.

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Dissertação de Mestrado Integrado em Engenharia Mecânica apresentada à Faculdade de Ciências e Tecnologia da Universidade de Coimbra.
Cada vez mais, a área da robótica se tem dedicado ao desenvolvimento de robôs móveis destinados a prestar serviços a humanos. Desta forma, são muitas as situações em que um robô móvel necessita de realizar uma acoplagem mecânica, fazendo-o através de um processo de docagem. O objetivo deste trabalho é o desenvolvimento de um sensor de docagem de baixo custo e complexidade com aplicação em robôs holonómicos, uma vez que a maior parte das soluções encontradas não cumpriam esses parâmetros. Assim, a implementação final do sistema é composta por três LEDs de infravermelhos instalados na estação.de docagem, e por uma câmara Pixart associada a um computador de placa única Arduino, colocados no robô. O robô consegue calcular a sua posição relativamente à estação de docagem com precisão de aproximadamente 1 centímetro a 1 metro de distância através da imagem observada. Com base nessa informação, toma decisões quanto ao seu movimento. O algoritmo de movimento foi desenvolvido com a robustez em mente, para que o computador central do robô tenha o mínimo de intervenção no processo. Infelizmente, não foi possível testar eficazmente o algoritmo de docagem, uma vez que todas as formas para o fazer apresentaram grandes obstáculos à sua implementação. No entanto, a minha expetativa e da equipa com quem trabalhei é de que, resolvidos os problemas com os simuladores e/ou com a plataforma robótica, seja possível testar do ponto de vista prático o algoritmo desenvolvido e confirmar o seu potencial.
Increasingly, the area of robotics has been dedicated to the development of mobile robots designed to serve humans. Thus, there are many situations where a mobile robot needs to perform a mechanical coupling, doing so through a docking process. The objective of this work is to develop a low-cost and low complexity docking sensor with application in holonomic robots, since most of the solutions found to this problem did not meet these qualities. Thus, the final implementation of the system is composed of three infrared LEDs installed in the docking station, and a Pixart camera associated with an Arduino single board computer, placed on the robot. The robot can calculate its position relative to the docking station with an accuracy of approximately 1 cm at 1 meter distance, from the observed image. Based on this information, it makes decisions about its movement. The motion algorithm was developed with robustness in mind, so that the robot’s central computer has minimal intervention in the process. Unfortunately it was not possible to effectively test the docking algorithm, since all the ways to do this presented great implementation hurdles. However, my spectation, which is shared with the team I worked with, is that once the problems with the simulators and/or robot platform have been solved, it will be possible to test the algorithm from a practical point of view, and therefore assess its potential.
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38

Osborne, Jason M. "On geometric control design for holonomic and nonholonomic mechanical systems." 2007. http://www.lib.ncsu.edu/theses/available/etd-05162007-123046/unrestricted/etd.pdf.

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39

Chang, Yeong Chan, and 張永昌. "Adaptive tracking control design of holonomic and nonholonomic mechanical systems." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/85077383386803225443.

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40

Dame, Jankuloski. "Virtual Holonomic Constraints and the Synchronization of Euler-Lagrange Control Systems." Thesis, 2012. http://hdl.handle.net/1807/33253.

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A virtual holonomic constraint (VHC) for an Euler-Lagrange Control System is a smooth relation between the configuration variables that can be made invariant through application of suitable feedback. In this thesis we investigate the role played by VHCs in the synchronization of Euler-Lagrange systems. We focus on two problems. For $N$ underactuated cart-pendulums, we design a smooth feedback that fully synchronizes the cart-pendulums while simultaneously stabilizing a periodic orbit corresponding to a desired oscillation for the pendulums. A by-product of our results is the ability to simultaneously synchronize the pendulums and stabilize the unstable upright equilibrium. The second synchronization problem investigated in this thesis is bilateral teleoperation, whereby a master robot is operated by a human while a slave robot synchronizes to the master. For two identical planar manipulators, we develop a methodology to achieve teleoperation in the presence of a hard surface, with simultaneous force control.
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41

Jheng, Huei Sian, and 鄭暉憲. "Adaptive Fuzzy Sliding-Mode Formation Controller Design for Non-Holonomic Multi-Robot Systems." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/29826583251013025932.

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42

YOU, LI-XING, and 游李興. "Tracking control designs for some kinds of both holonomic and nonholonomic constrained mechanical systems." Thesis, 1992. http://ndltd.ncl.edu.tw/handle/65050459339806569544.

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43

Bohnet, Doris. "Partially hyperbolic diffeomorphisms with a compact center foliation with finite holonomy." Phd thesis, 2011. http://tel.archives-ouvertes.fr/tel-00782664.

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On démontre que les difféomorphismes partiellement hyperboliques admettant un feuilletage central invariant compact sont dynamiquement cohérent et en plus ils ont la propriété de pistage. En supposant une direction instable uni-dimensionnelle et orientée on peut prouver que le difféomorphisme projette en un automorphisme hyperbolique de tore dans l'espace des feuilles centrales.
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44

Chhabra, Robin. "A Unified Geometric Framework for Kinematics, Dynamics and Concurrent Control of Free-base, Open-chain Multi-body Systems with Holonomic and Nonholonomic Constraints." Thesis, 2014. http://hdl.handle.net/1807/65650.

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This thesis presents a geometric approach to studying kinematics, dynamics and controls of open-chain multi-body systems with non-zero momentum and multi-degree-of-freedom joints subject to holonomic and nonholonomic constraints. Some examples of such systems appear in space robotics, where mobile and free-base manipulators are developed. The proposed approach introduces a unified framework for considering holonomic and nonholonomic, multi-degree-of-freedom joints through: (i) generalization of the product of exponentials formula for kinematics, and (ii) aggregation of the dynamical reduction theories, using differential geometry. Further, this framework paves the ground for the input-output linearization and controller design for concurrent trajectory tracking of base-manipulator(s). In terms of kinematics, displacement subgroups are introduced, whose relative configuration manifolds are Lie groups and they are parametrized using the exponential map. Consequently, the product of exponentials formula for forward and differential kinematics is generalized to include multi-degree-of-freedom joints and nonholonomic constraints in open-chain multi-body systems. As for dynamics, it is observed that the action of the relative configuration manifold corresponding to the first joint of an open-chain multi-body system leaves Hamilton's equation invariant. Using the symplectic reduction theorem, the dynamical equations of such systems with constant momentum (not necessarily zero) are formulated in the reduced phase space, which present the system dynamics based on the internal parameters of the system. In the nonholonomic case, a three-step reduction process is presented for nonholonomic Hamiltonian mechanical systems. The Chaplygin reduction theorem eliminates the nonholonomic constraints in the first step, and an almost symplectic reduction procedure in the unconstrained phase space further reduces the dynamical equations. Consequently, the proposed approach is used to reduce the dynamical equations of nonholonomic open-chain multi-body systems. Regarding the controls, it is shown that a generic free-base, holonomic or nonholonomic open-chain multi-body system is input-output linearizable in the reduced phase space. As a result, a feed-forward servo control law is proposed to concurrently control the base and the extremities of such systems. It is shown that the closed-loop system is exponentially stable, using a proper Lyapunov function. In each chapter of the thesis, the developed concepts are illustrated through various case studies.
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45

Brion, E., V. M. Akulin, I. Dumer, Gil Harel, and G. Kurizki. "Coherence protection by random coding." 2005. http://hdl.handle.net/10454/3991.

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No
We show that the multidimensional Zeno effect combined with non-holonomic control allows one to efficiently protect quantum systems from decoherence by a method similar to classical random coding. The method is applicable to arbitrary error-inducing Hamiltonians and general quantum systems. The quantum encoding approaches the Hamming upper bound for large dimension increases. Applicability of the method is demonstrated with a seven-qubit toy computer.
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