Pour fabriquer des produits de petites tailles, appelés micro-produits, l'utilisation de systèmes de production de dimensions habituelles conduit à des problèmes difficile à surmonter : coûts d'investissement et de fonctionnement des outils de production et problèmes techniques à cause des éffets d'echelle. Il en résulte une situation non concurrentielle même pour des systèmes automatisés.<br />La solution d'avenir consiste à disposer de systèmes de production dont les dimensions et les coûts sont en rapport avec les produits concernés : c'est le concept de micro-usine (microfactory).<br />L'objectif de cette thèse porte sur la conception et la commande d'une station de micromanipulation dédiée à une micro-usine. Afin d'assurer une flexibilité maximale à la micro-usine, nous proposons d'aborder la problématique de sa conception en développant à son maximum le concept de modularité. Il semble être une clé pour intégrer les spécificités d'un microsystème de production. Cette modularité doit se trouver au niveau de la commande, autant pour les tâches à réaliser que pour le pilotage de la station de micromanipulation.

O fenômeno de stick-slip, no processo de perfuração de poços de petróleo, é propiciado pela interação entre broca e formação rochosa e pode dar origem a grandes oscilações na velocidade angular podendo provocar danos irreparáveis ao processo. Neste trabalho, analisa-se o desempenho de leis de controle aplicadas à mesa rotativa (responsável por movimentar a coluna de perfuração), visando à redução de stick-slip e de oscilações da velocidade angular da broca. As leis de controle implementadas são do tipo PI (Proporcional-Integral), com parcelas de torque aplicado à mesa rotativa, proporcional e integral à velocidade da mesa, podendo ser com peso na broca constante ou variável. Para a coluna de perfuração, foi proposto um modelo em elementos finitos com função de forma linear. O torque na broca foi modelado segundo atrito de Coulomb pela forma não regularizada, curva esta ajustada pelos dados empíricos conforme propostas da literatura. Diversos critérios de desempenho foram analisados e foi observado que a minimização do desvio médio da velocidade angular em relação à referência propicia melhores condições de operação. Análises paramétricas dos ganhos de controle proporcional e integral foram realizadas, dando origem a curvas de nível para o desvio médio de velocidade angular na broca. A partir destas curvas, foram definidas regiões de estabilidade nas quais o desvio é aceitável. Estas regiões foram observadas serem maiores para menores pesos na broca e maiores velocidades angulares de referência e vice-versa. A adição do controle do peso na broca permitiu uma redução global dos níveis de desvio médio de velocidade angular, dando origem a um aumento das regiões de estabilidade do processo de perfuração. / The stick-slip phenomenon, in the process of drilling oil wells, due to the interaction between drill and rock formation can lead to large fluctuations in drill-bit angular velocity and, thus, cause irreparable damage to the process. In this work, the performance of control laws applied to the rotary table (responsible for moving the drill string) is analyzed, in order to reduce stick-slip and drill-bit angular velocity oscillations. The control laws implemented are based on a PI (Proportional-Integral) controller, for which the torque applied to the rotating table has components proportional and integral to table angular velocity with constant or variable WOB (Weight On Bit). For the drillstring, a finite element model with a linear interpolation was proposed. The torque on the drill-bit was modeled by a non-regularized Coulomb friction model, with parameters that were adjusted using empirical data proposed in literature. Several performance criteria were analyzed and it was observed that the minimization of the mean deviation of the drill-bit angular velocity relative to the target one would provide the best operating condition. Parametric analyses of proportional and integral control gains were performed, yielding level curves for the mean deviation of drill-bit angular velocity. From these curves, stability regions were defined in which the deviation is acceptable. These regions were observed to be wider for smaller values of WOB and higher values of target angular velocity and vice-versa. The inclusion of a controlled dynamic WOB reduced the levels of mean deviation of angular velocity, leading to improved stability regions for the drilling process.

No description available.

Die Kontaktverhältnisse zwischen Reifen und Fahrbahn bestimmen die maximal übertragbaren Beschleunigungs-, Brems- und Seitenkräfte des Fahrzeugs und sind daher für die Fahrsicherheit von großer Bedeutung. In dieser Arbeit wird ein Modell zur numerisch effizienten Simulation der hochfrequenten Dynamik einzelner Reifenprofilblöcke entwickelt. Der vorgestellte Modellansatz nutzt einerseits die Vorteile der Finite-Elemente-Methode, welche die Bauteilstruktur detailliert auflösen kann, bei der jedoch lange Rechenzeiten in Kauf genommen werden. Andererseits profitiert der vorgestellte Modellansatz von den Vorteilen stark vereinfachter Mehrkörpersysteme, welche die Berechnung der hochfrequenten Dynamik und akustischer Phänomene erlauben, jedoch strukturdynamische Effekte und das Kontaktverhalten in der Bodenaufstandsfläche des Reifens nur begrenzt abbilden können. Das hier vorgestellte Modell berücksichtigt in einem modularen Ansatz die Effekte der Strukturdynamik, der lokalen Reibwertcharakteristik, der nichtlinearen Wechselwirkungen durch den Kontakt mit der rauen Fahrbahnoberfläche und des lokalen Verschleißes. Die erforderlichen Modellparameter werden durch geeignete Experimente bestimmt. Ein Schwerpunkt der Arbeit liegt in der Untersuchung reibungsselbsterregter Profilblockschwingungen bei Variation der Modell- und Prozessparameter. Zur realistischen Betrachtung des Reifenprofilblockverhaltens erfolgt eine Erweiterung des Modells um eine Abrollkinematik, die tiefere Einblicke in die dynamischen Vorgänge in der Bodenaufstandsfläche des Reifens ermöglicht. Diese Simulationen lassen eine Zuordnung der aus der Literatur bekannten zeitlichen Abfolge von Einlaufphase, Haftphase, Gleitphase und Ausschnappphase zu. Es zeigen sich bei bestimmten Kombinationen aus Fahrzeuggeschwindigkeit und Schlupfwert ausgeprägte Stick-Slip-Schwingungen im akustisch relevanten Frequenzbereich. Das Modell erlaubt die Untersuchung des Einflusses der Profilblockgeometrie, der Materialparameter, der Fahrbahneigenschaften sowie der Betriebszustände auf den resultierenden Reibwert, auf das lokale Verschleißverhalten sowie auf das Auftreten hochfrequenter reibungsselbsterregter Schwingungen. Somit ermöglicht das Modell ein vertieftes Verständnis der Vorgänge im Reifen-Fahrbahn-Kontakt und der auftretenden Wechselwirkungen zwischen Struktur- und Kontaktmechanik. Es kann eine Basis für zukünftige Optimierungen des Profilblocks zur Verbesserung wesentlicher Reifeneigenschaften wie Kraftschlussverhalten, Verschleiß und Akustik bilden. / The contact conditions between tyre and road are responsible for the maximum acceleration, braking and side forces of a vehicle. Therefore, they have a large impact on the driving safety. Within this work a numerically efficient model for the simulation of the high-frequency dynamics of single tyre tread blocks is developed. The presented modelling approach benefits the advantage of the finite element method to resolve the component structure in detail. However, a long computation time is accepted for these finite element models. Moreover, the presented modelling approach makes use of the advantage of simplified multibody systems to calculate the high-frequency dynamics and acoustic phenomena. However, structural effects and the contact behaviour in the tyre contact patch can be covered only to a minor degree. The model treated here considers the effects of structural dynamics, the local friction characteristic, the non-linear interaction due to the contact with the rough road surface and local wear. The required model parameters are determined by appropriate experiments. One focus of this work is the investigation of self-excited tread block vibrations under variation of the model and process parameters. In order to realistically investigate the tread block behaviour the model is extended with regard to rolling kinematics which provides a deeper insight into the dynamic processes in the tyre contact patch. The corresponding simulations allow the allocation of the run-in phase, sticking phase, sliding phase and snap-out which is reported in the literature. For certain combinations of vehicle velocity and slip value pronounced stick-slip vibrations occur within the acoustically relevant frequency range. The model enables to study the influence of the tread block geometry, the material properties, the road surface characteristics and the operating conditions on the resulting tread block friction coefficient, local tread block wear and the occurrence of high-frequency self-excited vibrations. The simulation results provide a distinct understanding of the processes in the tyre/road contact and the interactions between structural mechanics and contact mechanics. They can be a basis for future tread block optimisations with respect to essential tyre properties such as traction, wear and acoustic phenomena.

[pt] Sistemas rotativos atuados através de um eixo flexível apresentam um grande desafio para estratégias de controle, uma vez que o atuador não está conectado diretamente ao sistema principal, causando efeitos de propagação de ondas e acúmulos e dissipações de energia no eixo. Este trabalho apresenta um estudo sobre uma das mais notórias aplicações deste problema, sistemas de perfuração de petróleo. Habitualmente, o sistema de perfuração é composto por um motor de topo conectado à broca através de milhares de metros de tubos de aço que transmitem o toque. Diversos tipos de vibrações podem ser observadas: Axiais, de flexão e torcionais, estas últimas ligadas ao fenomeno stick-slip. Para um completo conhecimento do problema, é necessário conhecer cada uma delas. Esta tese trata especificamente das vibrações torsionais através de uma análise com dois diferentes modelos, um primeiro mais simples de fois graus de liberdade (inércia, mola torcional, amortecedor), e um segundo mais completo discretizado em 20 graus de liberdade capaz de considerar a masssa do eixo e efeitos de propagação de ondas mecânicas no eixo. Este trabalho inclui aidna a construção de uma bancada em escala reduzida para observar os fenômenos associados as vibraçoes torcionais. São apresentados ainda estudos numéricos e experimentais de técnicas de controle de minimizar os efeitos do atrito na dinâmica torcional do sistema. Duas estrututas de controle são estudadas nesta tese a fim de reduzir vibrações torcionais em colunas de perfuração. A primeira é um controle simples, de malha aberta, baseado no comportamento do sistema. A segunda é o controle adaptativo L1, que faz uso de um modelo de refeência do sistema em sua estrutura. / [en] Systems actuated trough a highly flexible shaft poses a big challenge to control strategies as the actuator is not connected directly to the end effector, causing propagation effects as well as an energy accumulation and dissipation in the shaft. This thesis focuses the study of one of the most investigated application of this type, the top driven drilling system used in the oil and gas industry. Usually, the drilling system is composed by a top drive linked to the drill bit trough hundreds or even thousands of meters of steel pipes. All kind of vibrations will be found: longitudinal deformations will be associated to the bit bouncing, flexional with rubbing, and torsional with stick-slip effects. A better understanding is only possible when each of these situations is carefully investigated. This thesis focuses on the torsional deformation of the highly flexible string and presents two different models for the drill string, the first is the most common single spring single damper model. The second one is a 20 DOF Lumped parameters that has the advantage of being able to consider the mass of the drill string and propagation of torsional waves in the shaft. The investigation includes the development of a test rig adequate for torsional vibrations under damping that may induce stick-slip in the system. Two control techniques are studied to reduce the torsional vibrations in drill strings with numerical and experimental results presented. The first is a behavior based open loop scheme control, which is very simple and effective to reduce stick-slip oscillations. The second one is the L1 adaptive control that uses a reference model on its structure.

Dans ce travail de thèse, le microscope à force atomique (AFM) a été utilisé comme outil de manipulation de haute précision pour construire des nanostructures plasmoniques avec des géométries définies et un réglage précis de la distance interparticulaire et également comme technique de spectroscopie d'absorption. Différentes études concernant les phénomènes pertinents pour la manipulation des nanoparticules et émergeant à l'interface substrat-nanoparticules, ont été réalisées. Des expériences de frottement menées sur diverses surfaces d'oxydes ont révélé un nouveau mécanisme de frottement à l’échelle nanométrique, expliqué par un modèle de potentiel d'interaction de type Lennard-Jones modifié. Les propriétés de frottement et d'adhésion de CTAB adsorbé sur silice sont également présentées. Des nano-bâtonnets d'or fonctionnalisés par du CTAB ont été manipulés par AFM afin de construire des nanostructures plasmoniques. La dernière partie de la thèse présente les efforts expérimentaux et théoriques pour démontrer la faisabilité de l'utilisation d'un AFM comme une technique de spectroscopie optoélectronique à base de force. / In this thesis work the atomic force microscope (AFM) was employed first as a high precision manipulation tool for building plasmonic nanostructures with defined geometries and precise tuning of interparticle distance and second as an absorption spectroscopy technique. Different studies regarding phenomena emerging at sample nanoparticle interface relevant for nanoparticle manipulation were performed. Friction experiments conducted on various oxide surfaces revealed a novel nanoscale stick slip friction mechanism, explained by a modified Lennard-Jones-like interaction potential model. Frictional and adhesion properties of CTAB adsorbed on silica are also reported. CTAB functionalized gold nanorods were used for building specific plasmonic particulate nanostructures. The final part of the thesis presents experimental and theoretical efforts to demonstrate the feasibility of using an AFM as a force-based optoelectronic spectroscopy technique.

O fenômeno de stick-slip, no processo de perfuração de poços de petróleo, é propiciado pela interação entre broca e formação rochosa e pode dar origem a grandes oscilações na velocidade angular podendo provocar danos irreparáveis ao processo. Neste trabalho, analisa-se o desempenho de leis de controle aplicadas à mesa rotativa (responsável por movimentar a coluna de perfuração), visando à redução de stick-slip e de oscilações da velocidade angular da broca. As leis de controle implementadas são do tipo PI (Proporcional-Integral), com parcelas de torque aplicado à mesa rotativa, proporcional e integral à velocidade da mesa, podendo ser com peso na broca constante ou variável. Para a coluna de perfuração, foi proposto um modelo em elementos finitos com função de forma linear. O torque na broca foi modelado segundo atrito de Coulomb pela forma não regularizada, curva esta ajustada pelos dados empíricos conforme propostas da literatura. Diversos critérios de desempenho foram analisados e foi observado que a minimização do desvio médio da velocidade angular em relação à referência propicia melhores condições de operação. Análises paramétricas dos ganhos de controle proporcional e integral foram realizadas, dando origem a curvas de nível para o desvio médio de velocidade angular na broca. A partir destas curvas, foram definidas regiões de estabilidade nas quais o desvio é aceitável. Estas regiões foram observadas serem maiores para menores pesos na broca e maiores velocidades angulares de referência e vice-versa. A adição do controle do peso na broca permitiu uma redução global dos níveis de desvio médio de velocidade angular, dando origem a um aumento das regiões de estabilidade do processo de perfuração. / The stick-slip phenomenon, in the process of drilling oil wells, due to the interaction between drill and rock formation can lead to large fluctuations in drill-bit angular velocity and, thus, cause irreparable damage to the process. In this work, the performance of control laws applied to the rotary table (responsible for moving the drill string) is analyzed, in order to reduce stick-slip and drill-bit angular velocity oscillations. The control laws implemented are based on a PI (Proportional-Integral) controller, for which the torque applied to the rotating table has components proportional and integral to table angular velocity with constant or variable WOB (Weight On Bit). For the drillstring, a finite element model with a linear interpolation was proposed. The torque on the drill-bit was modeled by a non-regularized Coulomb friction model, with parameters that were adjusted using empirical data proposed in literature. Several performance criteria were analyzed and it was observed that the minimization of the mean deviation of the drill-bit angular velocity relative to the target one would provide the best operating condition. Parametric analyses of proportional and integral control gains were performed, yielding level curves for the mean deviation of drill-bit angular velocity. From these curves, stability regions were defined in which the deviation is acceptable. These regions were observed to be wider for smaller values of WOB and higher values of target angular velocity and vice-versa. The inclusion of a controlled dynamic WOB reduced the levels of mean deviation of angular velocity, leading to improved stability regions for the drilling process.

Les bruits automobiles induits par le frottement sont à l’origine de nombreuses plaintes clients et occasionnent des coûts de garantie considérables pour les constructeurs automobiles. Les objectifs de la thèse consistent à comprendre la physique à l’origine de ces bruits et proposer des méthodologies de simulation afin de les éradiquer. Un système générique est tout d’abord étudié. Ce système discret met en jeu un contact entre deux masses et une loi de frottement de Coulomb présentant une discontinuité à vitesse relative nulle. Des calculs de valeurs propres complexes de ce système linéarisé autour de sa position d’équilibre glissant sont menés et montrent la présence d’instabilités par flottement voire par divergence. Les simulations temporelles montrent quant à elles que les non-linéarités de contact permettent de stabiliser les niveaux vibratoires en cas d’instabilité selon quatre régimes distincts. De plus, malgré ses trois degrés de liberté, ce système est capable de reproduire les mécanismes de stick-slip, sprag-slip et couplage modal ainsi que les bruits de crissement, grincement et craquement rencontrés sur les systèmes automobiles. Des études paramétriques sont également présentées et mettent en avant des bifurcations de Hopf ainsi que l’effet déstabilisant potentiellement induit par l’amortissement. Des méthodologies permettant de catégoriser les réponses en termes de bruit et de mécanisme sont par la suite proposées. Les occurrences et risques de ces derniers sont alors analysés et des tendances sont dégagées. Enfin, la relation entre les bruits et les mécanismes est établie. L’attention est ensuite portée sur un système automobile particulier. Afin d’étudier son comportement crissant, les analyses de stabilité et les simulations temporelles sont désormais menées sur des modèles éléments-finis. Les simulations temporelles permettent d’observer l’établissement de vibrations auto-entretenues et d’identifier, parmi tous les modes instables prédits lors des analyses de stabilité, celui qui est réellement à l’origine de l’instabilité. L’effet du coefficient de frottement sur les motifs de coalescence et les cycles limites est également investigué. Le risque de crissement est ensuite évalué pour des conditions d’utilisation variées du système. La méthodologie, basée sur des analyses de stabilité, permet de retrouver les principaux constats expérimentaux obtenus sur banc d’essai. Le rôle des géométries et des matériaux constituant le système est également discuté. Enfin, une solution permettant de réduire de façon significative le risque de crissement est proposée. / Automotive friction-induced noises are the source of many customer complaints and lead to hugewarranty costs for car manufacturers. The objectives of the thesis are to improve the understanding ofthe physics at the origin of these noises and to propose numerical methodologies to eradicate them.A generic system is first investigated. This discrete system includes a contact between two masses anda Coulomb friction law with a discontinuity at zero relative velocity. Calculations of complex eigenvaluesof the linearized system around its sliding equilibrium position are carried out and show the presence offlutter and even divergence instabilities. Time simulations show that contact non-linearities permit tostabilize the vibrational levels in case of instability according to four distinct behaviors. Furthermore,despite its three degrees of freedom, this system is able to reproduce the stick-slip, sprag-slip and modecouplingmechanisms as well as the squeal, squeak and creak noises encountered in automotive systems.Parametric studies are also presented and highlight Hopf bifurcations as well as the destabilizing effectpotentially induced by damping. Methodologies allowing the categorization of the responses in termsof noise and mechanism are then proposed. Occurrences and risks of these noises and mechanismsare thus analyzed and trends are highlighted. The relationship between noises and mechanisms is alsoestablished.A specific automotive system is then considered. In order to study its squeal behavior, stabilityanalysis and time simulations are now carried out on finite element models. Time simulations allowto observe the establishment of self-excited vibrations and to identify, among all the unstable modespredicted by the stability analysis, the one which is actually the source of the instability. The effectof friction on the coalescence patterns and limit cycles is also investigated. The risk of squeal is thenevaluated in different operating conditions. The methodology, based on stability analysis, leads toresults in good agreement with the experimental observations. The role of geometries and materialsconstituting the system is also discussed. Finally, a solution with significantly low risk of squeal isproposed.

Der Reibkontakt zwischen zwei Körpern hat entscheidende Einflüsse auf die Schwingungsselbsterregung. Da in der Literatur bisher vorwiegend ein Festkörper-Festkörper-Kontakt im Fokus steht, beschäftigt sich diese Arbeit mit einem Partikel-Festkörper-Kontakt. Dabei stehen Partikelsysteme in Form von Schüttgütern im Mittelpunkt. Ein bekanntes Beispiel solcher selbsterregten Schwingungen sind Silovibrationen. Dies sind Stick-Slip-Schwingungen beim Entleerungsvorgang von dünnwandigen Metallsilos. Untersuchungen mittels Fouriertransformation zeigen, dass die hörbaren Schwingungen sich aus einer Grundharmonischen und mehreren Oberwellen zusammensetzen. Diese Frequenzen sind allerdings weit oberhalb der numerisch untersuchten ersten Eigenfrequenzen der Silos. Ein Schwerpunkt der Arbeit liegt in den experimentellen Untersuchungen der Stick-Slip-Frequenz eines Schüttgut-Wand-Systems in einem speziell dafür entwickelten Versuchsstand. Es werden sowohl Systemkenngrößen, wie z.B. Geschwindigkeit, Systemsteifigkeit oder Masse, als auch tribologische Kenngrößen, wie z.B. Kontaktfläche oder -pressung, Materialkombination und Wandbeschaffenheit, auf ihren Einfluss auf die Stick-Slip-Frequenz untersucht. Ergänzend dazu wird die reale Kontaktfläche im statischen Zustand und bei einer äußeren dynamischen Anregung zwischen den Randpartikeln und einem Festkörper untersucht. Des Weiteren wird der tatsächliche Reibwert über der Relativgeschwindigkeit in Form einer Reibhysterese gemessen. In den Simulationsstudien wird ein Modell eines Reibschwingers vorgestellt und untersucht. Hier zeigen sich bereits bei einer stationären Kennlinie große Unterschiede in der Stick-Slip-Neigung und der Frequenz. In einer Modellerweiterung mittels einer zeitabhängigen Reibhysterese werden weiterführende Modellstudien getätigt. Hierbei steht vor allem das zeitabhängige Reibverhalten in der Haft- und Gleitphase im Fokus der Untersuchungen. / The friction contact between two bodies has an important influence on self-excited vibrations. Often the main focus is on a solid-solid contact. Therefore, this thesis focuses on a particle-solid contact, represented as the interaction between a bulk solid and a wall. Silo vibrations are a well known example of this kind of self-excited vibrations. Stick-slip vibrations occure during the discharging of thin walled metal silo. The hearable vibrations consist of a basic harmonic and some higher harmonics. The frequencies can be detected by a Fourier transform. One main focus of this thesis is the experimental investigation of the stick-slip frequency of a bulk solid-wall system. Therefore, a special test rig is designed. The investigation concentrates on system parameters, e.g. velocity, system stiffness or mass, on tribological parameters, e.g. contact area, pressure, material combination and wall surfaces, and their influence on the stick-slip frequency. Additional, the real contact area between particles in wall proximity and the wall itself is investigated in a static situation and during an external dynamic excitation. Furthermore, the real friction coefficient over the relative velocity will be measured. A model of a single mass friction oscillator will be presented and investigated in the simulation studies. Even with stationary friction characteristics this studies show big differences in the stick-slip stability and frequency. Henceforth, an advanced model with friction characteristics dependent on time in the form of a friction hysteresis is presented. There, the main focus is on the time dependent friction behaviour during the stick and slip phase of the oscillation.

La capacité de réaliser des tâches robotiques dextres à l'échelle nanométrique dans un microscope électronique à balayage (MEB) est un enjeu crucial pour les nanotechnologies. Les systèmes nano-robotiques dédiés à des applications sous MEB ont ainsi émergé dans de nombreux laboratoires de robotique. Ils peuvent être composés d'un ou de plusieurs actionneurs intégrés à des plateformes nano-robotiques avec un ou plusieurs effecteurs. L’actionneur Piézoélectrique Stick-Slip (PSS) est l'un des meilleurs candidats pour actionner les systèmes nano-robotiques dédiés à des applications sous MEB car il est capable d'effectuer un positionnement grossier avec une plage de déplacement millimétrique et un positionnement précis avec une plage de déplacement de quelques micromètres. La modélisation des actionneurs PSS est complexe notamment en raison de leur mode de fonctionnement hybride. La commande est également difficile à cause de plusieurs caractéristiques liées aux actionneurs PSS, soient le frottement, l’hystérésis et les vibrations non-amorties, qui dégradent leur performances en termes de précision et de vitesse. Ce travail porte sur la modélisation et la commande d'un système nano-robotique à 3 axes dédié à des applications sous MEB et actionné par des actionneurs piézoélectriques de type stick-slip. Chaque élément et caractéristique des actionneurs PSS ont été analysés et modélisés afin d’établir par la suite un modèle dynamique complet capable de décrire les deux modes de fonctionnement, à savoir le mode balayage et pas à pas. Pour chacun de ces deux modes, des lois de commande ont ainsi été développées pour les actionneurs PSS. Des stratégies de commande robuste ont été synthétisées pour des objectifs de positionnement rapide et à haute résolution en mode balayage. De telles performances sont fondamentales dans plusieurs tâches micro-/nano-robotique tels que le nano-assemblage rapide et précis et la nano-caractérisation des matériaux. Une commande proportionnelle en fréquence et en amplitude est synthétisée pour effectuer un déplacement millimétrique en mode pas à pas. Ceci est motivé par les applications robotiques pour lesquelles une large plage de déplacement est requise, tels que le scan de grandes surfaces et les phases d’approche d’une sonde d’un échantillon à manipuler. Une stratégie de commutation qui combine les modes balayage et pas à pas, est alors proposée pour remédier au manque de précision en mode pas à pas, lors de passage d’un grand à un petit déplacement. Ce travail a donné lieu à des résultats qui ouvrent de nouvelles perspectives pour l'utilisation des actionneurs PSS dans les systèmes nano-robotiques dédiés à des applications sous MEB. / The capability of doing dexterous robotic tasks at the nanometer scale inside a Scanning Electron Microscope (SEM) is a critical issue for nanotechnologies. SEM-integrated nano-robotic systems have consequently emerged in many robotics laboratories. They can be composed of one or more actuators assembled into nano-robotic platforms with one or several effectors. Piezoelectric Stick-Slip (PSS) actuators is one of the best candidate to actuate SEM-integrated nano-robotic systems because it is able to perform coarse positioning with millimeter displacement range and fine positioning with travel range of few micrometers. Modeling of PSS actuators is complex and difficult mainly because of their hybrid operating mode. Furthermore, control is challenging due to several characteristics related to PSS actuators, namely friction, hysteresis and undamped vibrations, which degrade their performance in terms of precision and speed. This work deals with modeling and control of a 3-axes SEM integrated nano-robotic system driven by piezoelectric stick-slip actuators. Each element and characteristic of PSS actuators are analyzed and modeled to thereafter establish a complete dynamic model able to describe the two functioning modes, namely the scanning and the stepping modes. PSS actuators are then controlled in each of these modes. Robust control strategies are developed to achieve high-resolution and fast positioning in scanning mode. Such performance is fundamental in several micro/nano-robotic tasks such as fast and accurate nano-assembly and nano-material characterization. A frequency/amplitude proportional controller is designed to perform millimeter displacement in stepping mode. This is motivated by robotic tasks where large motion is required, such as large surfaces scan and bringing a probe close to a sample to manipulate. A switched strategy, which combines scanning and stepping motion modes, is then proposed to remedy to the lack of precision in stepping motion, when passing from a large to a small displacement. This work has given rise to results which open new perspectives to the use of PSS actuators in SEM integrated nano-robotic systems.