The master’s thesis submitted deals with realtime rendering of three-dimensional CAD data using Vulkan API. The thesis also covers possibilities of connecting the API with VRUT, complex solution for renderig developed by ŠKODA AUTO a.s. Design of such connection is presented in form of Vulkan rendering plugin for VRUT application. Performance of the designed module is compared with another rendering module, based on different rendering technologies.

Indiana University-Purdue University Indianapolis (IUPUI) / Compressed air is a powerful source of stored energy and is used in a variety of applications varying from painting to pressing, making it a versatile tool for manufacturers. Due to the high cost and energy consumption associated with producing compressed air and it’s use within industrial manufacturing, it is often referred to as a fourth utility behind electricity, natural gas, and water. This is the reason why air compressors and associated equipment are often the focus for improvements in the eyes of manufacturing plant managers. As compressed air can be used in multiple ways, the methods used to extract and transfer the energy from this source vary as well. Compressed air can flow through different types of piping, such as aluminum, Polyvinyl Chloride (PVC), rubber, etc. with varying hydraulic diameters, and through different fittings such as 90-degree elbows, T-junctions, valves, etc. which can cause one of the major concerns related to managing the energy consumption of an air compressor, and that is the waste of air through leaks. Air leaks make up a considerable portion of the energy that is wasted in a compressed air system, as they cause a multitude of problems that the compressor will have to make up for to maintain the steady operation of the pneumatic devices on the manufacturing floor that rely on compressed air for their application. When air leaks are formed within the compressed air piping network, they act as continuous consumers and cause not only the siphoning off of said compressed air, put also reduce the pressure that is needed within the pipes. The air compressors will have to work harder to compensate for the losses in the pressure and the amount of air itself, causing an overconsumption of energy and power. Overworking the air compressor also causes the internal equipment to be stretched beyond its capabilities, especially if they are already running at full loads, reducing their total lifespans considerably. In addition, if there are multiple leaks close to the pneumatic devices on the manufacturing floor, the immediate loss in pressure and air can cause the devices to operate inefficiently and thus cause a reduction in production. This will all cumulatively impact the manufacturer considerably when it comes to energy consumption and profits. There are multiple methods of air leak detection and accounting that currently exist so as to understand their impact on the compressed air systems. The methods are usually conducted when the air compressors are running but during the time when there is no, or minimal, active consumption of the air by the pneumatic devices on the manufacturing floor. This time period is usually called non-production hours and generally occur during breaks or between employee shift changes. This time is specifically chosen so that the only air consumption within the piping is that of the leaks and thus, the majority of the energy and power consumed during this time is noted to be used to feed the air leaks. The collected data is then used to extrapolate and calculate the energy and power consumed by these leaks for the rest of the year. There are, however, a few problems that arise when using such a method to understand the effects of the leaks in the system throughout the year. One of the issues is that it is assumed that the air and pressure lost through the found leaks are constant even during the production hours i.e. the hours that there is active air consumption by the pneumatic devices on the floor, which may not be the case due to the increased air flow rates and varying pressure within the line which can cause an increase in the amount of air lost through the same orifices that was initially detected. Another challenge that arises with using only the data collected during a single non-production time period is that there may be additional air leaks that may be created later on, and the energy and power lost due to the newer air leaks would remain unaccounted for. As the initial estimates will not include the additional losses, the effects of the air leaks may be underestimated by the plant managers. To combat said issues, a continuous method of air leak analyses will be required so as to monitor the air compressors’ efficiency in relation to the air leaks in real time. By studying a model that includes both the production, and non-production hours when accounting for the leaks, it was observed that there was a 50.33% increase in the energy losses, and a 82.90% increase in the demand losses that were estimated when the effects of the air leaks were observed continuously and in real time. A real time monitoring system can provide an in-depth understanding of the compressed air system and its efficiency. Managing leaks within a compressed air system can be challenging especially when the amount of energy wasted through these leaks are unaccounted for. The main goal of this research was to find a nonintrusive way to calculate the amount of air as well as energy lost due to these leaks using time series pressure measurements. Previous studies have shown a strong relationship between the pressure difference, and the use of air within pneumatic lines, this correlation along with other factors has been exploited in this research to find a novel and viable method of leak accounting to develop a Continuous Air Leak Monitoring (CALM) system.

Robot mapping is a major field of research in robotics. Its basic task is to combine (register) spatial data, usually gained from range devices, to a single data set. This data set is called global map and represents the environment, observed from different locations, usually without knowledge of their positions. Various approaches can be classified into groups based on the type of sensor, e.g. Lasers, Microsoft Kinect, Stereo Image Pair. A major disadvantage of current methods is the fact, that they are derived from hardly scalable 2D approaches that use a small amount of data. However, 3D sensing yields a large amount of data in each 3D scan. Autonomous mobile robots have limited computational power, which makes it harder to run 3D robot mapping algorithms in real-time. To remedy this limitation, the proposed research uses mid-level geometric features (lines and ellipses) to construct 3D geometric primitives (planar patches, cylinders, spheres and cones) from 3D point data. Such 3D primitives can serve as distinct features for faster registration, allowing real-time performance on a mobile robot. This approach works in real-time, e.g. using a Microsoft Kinect to detect planes with 30 frames per second. While previous approaches show insufficient performance, the proposed method operates in real-time. In its core, the algorithm performs a fast model fitting with a model update in constant time (O(1)) for each new data point added to the model using a three stage approach. The first step inspects 1.5D sub spaces, to find lines and ellipses. The next stage uses these lines and ellipses as input by examining their neighborhood structure to form sets of candidates for the 3D geometric primitives. Finally, candidates are fitted to the geometric primitives. The complexity for point processing is O(n); additional time of lower order is needed for working on significantly smaller amount of mid-level objects. The real-time performance suggests this approach as a pre-processing step for 3D real-time higher level tasks in robotics, like tracking or feature based mapping. In this thesis, I will show how these features are derived and used for scene registration. Optimal registration is determined by finding plane-feature correspondence based on mutual similarity and geometric constraints. Our approach determines the plane correspondence in three steps. First step computes the distance between all pairs of planes from the first scan to all pair of planes from the second scan. The distance function captures angular, distance and co-planarity differences. The resulting distances are accumulated in a distance matrix. The next step uses the distance matrix to compute the correlation matrix between planes from the first and second scan. Finally plane correspondence is found by finding the global optimal assignment from the correlation matrix. After finding the plane correspondence, an optimal pose registration is computed. In addition to that, I will provide a comparison to existing state-of-the-art algorithms. This work is part of an industry collaboration effort sponsored by the National Institute of Standards and Technology (NIST), aiming at performance evaluation and modeling of autonomous navigation in unstructured and dynamic environments. Additional field work, in the form of evaluation of real robotic systems in a robot test arena was performed. / Computer and Information Science / Accompanied by two .mp4 files.

Cette thèse s’inscrit dans le domaine de l’automatique, et a pour but de fournir des outils utiles à l’atterrissage en mer d’hélicoptères (sur navire ou plateforme) et employés dans le cadre d’un potentiel pilotage automatique. L’objectif a donc été de développer une série de lois de commande pilotées manuellement, puis commandées de façon autonome à l’aide d’informations caméra. Les lois ainsi développées à l’aide de modèles dynamiques d’hélicoptères, limitations mécaniques incluses, se basent sur les critères de Qualité de Vol issus de la norme ADS-33. L’ensemble a fait appel à une approche anti-windup pour améliorer la robustesse face aux situations d’actionneurs en saturation. Enfin les lois issues de ces travaux ont été testées en temps-réel sur le banc de pilotage d’hélicoptères de l’ONERA Salon-de-Provence. / This thesis is related to the automatic & control engineering field, and itsmain goal is to provide useful tools for ship landing missions, tools that can be used fora potential autopilot. The objective has been to develop a series of control laws manuallypiloted, then automatically controlled by visual servoing using identified image features. Thelaws developped thanks to helicopter models with mechanical limitations were based on flyingqualities criteria from the ADS-33 standard. The process also defines an anti-windup approachto cope with actuator saturations. Finally the main results were assessed in real time withthe ONERA rotorcraft flight test bench at ONERA Salon-de-Provence.

O Epstein-Barr Vírus (EBV) é um vírus da família Herpes (HHV-4), presente em grande parte da população mundial. É o agente etiológico da mononucleose infecciosa e da leucoplasia pilosa. A leucoplasia pilosa é uma doença epitelial benigna associada ao EBV, caracterizada pela reprodução replicativa do EBV nas células do epitélio oral, e é uma das mais freqüentes lesões oportunistas em pacientes HIV positivos, sendo menos freqüente apenas que a candidíase, com uma prevalência média entre 10 % e 30%. Por ser uma lesão oportunista bucal fortemente relacionada com a infecção pelo HIV e com a imunossupressão, seu diagnóstico é importante, pois pode sugerir o diagnóstico da infecção em pacientes de sorologia desconhecida para o HIV, e auxiliar no estadiamento da doença. Sua detecção e correto diagnóstico são de particular importância por essa condição estar relacionada à capacidade imune do paciente. Além disso, em pacientes já diagnosticados, ela é indicadora da progressão da doença e da eficácia da terapia antirretroviral. O objetivo desse estudo foi avaliar a presença e a quantidade do EBV na saliva e no sangue de pacientes infectados pelo HIV atendidos no CAPE-FOUSP, verificar a presença clínica de leucoplasia pilosa, estabelecendo a possibilidade da existência de vínculo entre a carga viral do EBV, a manifestação clínica da lesão e a carga viral do HIV. Também se buscou estabelecer relação entre o tipo de terapia antirretroviral em uso e a presença de leucoplasia pilosa, bem como estabelecer relação entre a carga viral do EBV na saliva e no sangue. Foram analisadas 20 lesões de leucoplasia pilosa, num total de 94 pacientes avaliados. Foi encontrada uma correlação positiva entre a Carga Viral do EBV no sangue e na saliva (p=0,001). Quanto maior a carga viral no sangue, maior a carga viral na saliva. Foi encontrada associação entre a Carga Viral do EBV na saliva e a presença de Leucoplasia Pilosa (p=0,045). Indivíduos com Leucoplasia Pilosa apresentam maior Carga Viral de EBV na saliva do que indivíduos sem essa lesão. Foi encontrada uma correlação positiva entre a Carga Viral do HIV e a Carga Viral do EBV na saliva (p=0,006) porém não no sangue. Quanto maior a carga viral de HIV, maior a carga viral do EBV na saliva. Foi encontrada correlação positiva entre a Carga Viral do EBV no sangue e as contagens de CD4 mais baixa registrada e a mais atual (p=0,028 e p=0,030 respectivamente). Quanto maior Carga Viral do EBV no sangue, maior a contagem de CD4. Não foi encontrada associação entre o tipo de medicação antirretroviral em uso e presença de lesão de leucoplasia pilosa. / The Epstein-Barr Virus (EBV) is a herpes virus family (HHV-4), is present in great part of the world population. It is the causative agent of infectious mononucleosis and oral hairy leukoplakia. Oral hairy leukoplakia is a benign epithelial disease associated with EBV, which is characterized by the replicative reproduction of EBV in oral epithelial cells, and is one of the most frequent opportunistic lesions in HIV positive patients, only less frequent than candidiasis, with an average prevalence between 10% and 30%. Being an opportunistic oral lesion strongly associated with HIV infection and immunosuppression, its diagnosis is important, because it may suggests the diagnosis of infection in patients of unknown HIV serology, and assist in the staging of the disease. Its detection and correct diagnosis are particularly important because this condition is related to the patient\'s immune capacity. Moreover, in patients already diagnosed, it is indicative of disease progression and effectiveness of antiretroviral therapy. The aim of this study was to evaluate the presence and quantity of EBV in saliva and blood of HIV-infected patients treated at the CAPE-FOUSP, verifying the presence of clinical OHL, establishing the possibility of the existence of a link between viral load and EBV, clinical manifestation of the lesion, and HIV viral load. It was also aimed to establish the relationship between the type of antiretroviral therapy in use and the presence of oral hairy leukoplakia, as well as establish the relationship between viral load of EBV in saliva and blood. We analyzed 20 lesions of oral hairy leukoplakia, a total of 94 patients. Found a positive correlation between viral load of EBV in blood and saliva (p = 0.001). The higher the viral load in blood, the higher the viral load in saliva. Association was found between viral load of EBV in saliva and the presence of oral hairy leukoplakia (p = 0.045).Individuals with oral hairy leukoplakia have a higher viral load of EBV in saliva than those without such injury. Found a positive correlation between viral load and HIV viral load of EBV in saliva (p = 0.006) but not in blood. The higher the viral load of HIV, the higher the viral load of EBV in saliva. A positive correlation was found between viral load of EBV in blood and CD4 counts the lowest recorded and most current (p = 0.028 and p = 0.030 respectively). The higher viral load of EBV in blood, increased CD4 count. No association was found between the type of antiretroviral medications in use and presence of oral hairy leukoplakia lesions.

Ressonância Magnética (RM) é uma técnica bastante versátil, pois é utilizada em muitas áreas de pesquisa, como biologia, física, química, engenharia e medicina. Apesar disso, constitui-se uma desvantagem o alto custo do equipamento e suas restrições físicas para alguns experimentos. Para reduzir essas desvantagens, o grupo de pesquisadores do CIERMag está desenvolvendo um equipamento de RMN multipropósito e, para complementá-lo, este trabalho vem desenvolver um subsistema non-real-time que gerencia os dispositivos periféricos de um experimento. Foi proposta uma rede de dispositivos que é controlada por um Raspberry Pi como elemento central, o qual está conectado ao terminal computadorizado do sistema através de uma rede local (Local Area Network - LAN) via Ethernet e conectado aos dispositivos periféricos via Serial Peripheral Interface (SPI). Com o objetivo de ser possível gerenciar qualquer tipo de dispositivo, foi desenvolvido um conjunto de parâmetros baseado no Transducer Electronic Data Sheet (TEDS), definido no padrão IEEE 1451, de modo que cada dispositivo, normalmente um transdutor, possui seu próprio. Foram elaboradas duas interfaces de software: uma desenvolvida em Python e a outra uma interface web HTML. Ambas as interfaces possuem as mesmas funcionalidades: editor e gerenciador de TEDS, visualização gráfica de medidas dos sensores e interface para os atuadores. / Magnetic Resonance (MR) is a very versatile technique, since it is used in many research areas such as biology, physics, chemistry, engineering and medicine. Despite this, the cost of the equipment and its physical restrictions in some experiments constitute a serious drawback. To minimize these problems, the CIERMag research team is developing multipurpose MR equipment and, to complement this equipment, this work develops a non-real-time subsystem that manages the peripheral devices of the experiment. It was proposed a network of devices controlled by a Raspberry Pi as its central element, which is connected to the terminal computer of the system. The protocol adopted for this was Ethernet via Local Area Network (LAN); communication with peripheral transducers was performed with the Serial Peripheral Interface (SPI). With the objective to be able to manage any type of device, we created parameter sets based on Transducer Electronic Data Sheet (TEDS), defined in the IEEE 1451 standard, so each device, normally a transducer, has its own parameter set. We created two software interfaces: one developed with Python and the other is a HTML web interface. Both have the same functionalities: a TEDS editor and manager, a graphical visualization of sensor measurements and also an actuator interface.

O Epstein-Barr Vírus (EBV) é um vírus da família Herpes (HHV-4), presente em grande parte da população mundial. É o agente etiológico da mononucleose infecciosa e da leucoplasia pilosa. A leucoplasia pilosa é uma doença epitelial benigna associada ao EBV, caracterizada pela reprodução replicativa do EBV nas células do epitélio oral, e é uma das mais freqüentes lesões oportunistas em pacientes HIV positivos, sendo menos freqüente apenas que a candidíase, com uma prevalência média entre 10 % e 30%. Por ser uma lesão oportunista bucal fortemente relacionada com a infecção pelo HIV e com a imunossupressão, seu diagnóstico é importante, pois pode sugerir o diagnóstico da infecção em pacientes de sorologia desconhecida para o HIV, e auxiliar no estadiamento da doença. Sua detecção e correto diagnóstico são de particular importância por essa condição estar relacionada à capacidade imune do paciente. Além disso, em pacientes já diagnosticados, ela é indicadora da progressão da doença e da eficácia da terapia antirretroviral. O objetivo desse estudo foi avaliar a presença e a quantidade do EBV na saliva e no sangue de pacientes infectados pelo HIV atendidos no CAPE-FOUSP, verificar a presença clínica de leucoplasia pilosa, estabelecendo a possibilidade da existência de vínculo entre a carga viral do EBV, a manifestação clínica da lesão e a carga viral do HIV. Também se buscou estabelecer relação entre o tipo de terapia antirretroviral em uso e a presença de leucoplasia pilosa, bem como estabelecer relação entre a carga viral do EBV na saliva e no sangue. Foram analisadas 20 lesões de leucoplasia pilosa, num total de 94 pacientes avaliados. Foi encontrada uma correlação positiva entre a Carga Viral do EBV no sangue e na saliva (p=0,001). Quanto maior a carga viral no sangue, maior a carga viral na saliva. Foi encontrada associação entre a Carga Viral do EBV na saliva e a presença de Leucoplasia Pilosa (p=0,045). Indivíduos com Leucoplasia Pilosa apresentam maior Carga Viral de EBV na saliva do que indivíduos sem essa lesão. Foi encontrada uma correlação positiva entre a Carga Viral do HIV e a Carga Viral do EBV na saliva (p=0,006) porém não no sangue. Quanto maior a carga viral de HIV, maior a carga viral do EBV na saliva. Foi encontrada correlação positiva entre a Carga Viral do EBV no sangue e as contagens de CD4 mais baixa registrada e a mais atual (p=0,028 e p=0,030 respectivamente). Quanto maior Carga Viral do EBV no sangue, maior a contagem de CD4. Não foi encontrada associação entre o tipo de medicação antirretroviral em uso e presença de lesão de leucoplasia pilosa. / The Epstein-Barr Virus (EBV) is a herpes virus family (HHV-4), is present in great part of the world population. It is the causative agent of infectious mononucleosis and oral hairy leukoplakia. Oral hairy leukoplakia is a benign epithelial disease associated with EBV, which is characterized by the replicative reproduction of EBV in oral epithelial cells, and is one of the most frequent opportunistic lesions in HIV positive patients, only less frequent than candidiasis, with an average prevalence between 10% and 30%. Being an opportunistic oral lesion strongly associated with HIV infection and immunosuppression, its diagnosis is important, because it may suggests the diagnosis of infection in patients of unknown HIV serology, and assist in the staging of the disease. Its detection and correct diagnosis are particularly important because this condition is related to the patient\'s immune capacity. Moreover, in patients already diagnosed, it is indicative of disease progression and effectiveness of antiretroviral therapy. The aim of this study was to evaluate the presence and quantity of EBV in saliva and blood of HIV-infected patients treated at the CAPE-FOUSP, verifying the presence of clinical OHL, establishing the possibility of the existence of a link between viral load and EBV, clinical manifestation of the lesion, and HIV viral load. It was also aimed to establish the relationship between the type of antiretroviral therapy in use and the presence of oral hairy leukoplakia, as well as establish the relationship between viral load of EBV in saliva and blood. We analyzed 20 lesions of oral hairy leukoplakia, a total of 94 patients. Found a positive correlation between viral load of EBV in blood and saliva (p = 0.001). The higher the viral load in blood, the higher the viral load in saliva. Association was found between viral load of EBV in saliva and the presence of oral hairy leukoplakia (p = 0.045).Individuals with oral hairy leukoplakia have a higher viral load of EBV in saliva than those without such injury. Found a positive correlation between viral load and HIV viral load of EBV in saliva (p = 0.006) but not in blood. The higher the viral load of HIV, the higher the viral load of EBV in saliva. A positive correlation was found between viral load of EBV in blood and CD4 counts the lowest recorded and most current (p = 0.028 and p = 0.030 respectively). The higher viral load of EBV in blood, increased CD4 count. No association was found between the type of antiretroviral medications in use and presence of oral hairy leukoplakia lesions.

Le prochain secteur à être fortement automatisé est sans doute celui du transport routier. D’abord en environnement peu complexe comme c’est déjà le cas sur autoroute, puis à terme dans les scénarios les plus difficiles, comme ceux rencontrés au coeur du trafic urbain. Une étape intermédiaire consiste à introduire des véhicules autonomes en milieu urbain, mais hors du trafic, comme sur des sites fermés. Ces environnements présentent des caractéristiques particulières, comme un encombrement important. Alors, pour être en mesure de naviguer en toute autonomie, les véhicules doivent être à la fois agiles, précis et sûrs, mais aussi efficaces, donc rapides. Ce travail de thèse adresse deux problématiques clés de la navigation autonome en milieu encombré : la planification et le suivi de chemin pour les véhicules à deux trains directeurs (4WS). En effet, la cinématique 4WS est la réponse des constructeurs au besoin d’agilité et nécessite le développement de techniques de commande adaptées. La planification de chemin en temps-réel permet l’évitement d’obstacles, de façon à rendre le service robuste aux aléas de l’environnement. Le contrôle automatique de la direction permet ensuite de suivre ces chemins avec précision. La principale difficulté concernant la planification de chemin est le contraste entre la faible puissance de calcul embarquée sur le véhicule et la forte contrainte temporelle qu’impose le besoin de réactivité. Il s’agit donc de choisir l’approche adéquate et de mettre en place les simplifications algorithmiques les plus efficaces, c’est-à-dire qui réduisent la quantité de calculs nécessaires sans réduire la qualité des chemins générés. De plus, la planification de chemin en milieu encombré pose le problème des impasses dans lesquelles les méthodes les plus réactives restent coincées. De fait, l’approche retenue consiste à construire une fonction de navigation en deux dimensions dont est extrait le chemin. Au sens des critères choisis, il est optimal pour un véhicule circulaire. Des stratégies sont alors mises en place pour adapter cet algorithme aux véhicules 4WS de forme rectangulaire, comme la notion centrale de double-chemin qui permet de représenter la trajectoire d’un mobile à trois degrés de liberté dans un espace en deux dimensions. Enfin, d’autres stratégies et heuristiques sont introduites pour optimiser les performances de l’algorithme de planification et lui permettre de générer des manoeuvres efficaces. Concernant le développement du contrôleur de direction, il s’agit de choisir le modèle d’évolution qui retranscrit au mieux le comportement du véhicule vis-à-vis du double chemin qu’il doit suivre, puis d’en déduire les lois de commande des trains avant et arrière. Ayant été éprouvé par de nombreux travaux, le modèle bicyclette 4WS a été choisi. Ce modèle cinématique permet d’introduire facilement des angles de dérive utiles à la compensation des glissements des pneus sur le sol, qu’ils soient dus à un manque d’adhérence ou à une géométrie imparfaite des trains. Des lois de commande par retour d’état sont ensuite synthétisées et une stratégie de gestion de la saturation des actionneurs est proposée. Enfin, ce premier contrôleur est décliné en une version prédictive qui apporte un suivi de chemin d’une grande stabilité sur les véhicules réels. Les contributions ont toutes été évaluées en simulation et lors d’expérimentations en vraie grandeur sur l’EZ10, une navette électrique 4WS industrielle. Enfin, il se trouve que les performances obtenues dépassent les attentes initiales. / The next sector to be highly automated is probably road transport. First in an uncomplicated environment as is already the case on highway, then eventually in the most difficult scenarios, such as those encountered at the heart of the urban traffic. An intermediate step is to introduce autonomous vehicles in urban areas, but outside traffic, as on closed sites. These environments have particular characteristics, they can be very cluttered. So to be able to navigate autonomously, the vehicles have to be agile, precise and safe, but also efficient, i.e. fast. This thesis addresses two key issues of autonomous navigation in cluttered environments: path planning and tracking for bi-steerable (4WS) vehicles. Indeed, the 4WS kinematics is the response of the manufacturers to the need for agility and requires the development of adapted control techniques. Real-time path planning allows the avoidance of obstacles in order to make the service robust to the vagaries of the environment. The automatic control of the direction then makes it possible to follow these paths with precision. The main difficulty about path planning is the contrast between the low onboard computing power and the high temporal constraints imposed by the need for reactivity. It is thus necessary to choose the appropriate approach and to implement the most efficient algorithmic simplifications, i.e. reducing the amount of calculations without reducing the quality of the generated paths. In addition, path planning in cluttered environment raises the problem of dead-ends in which the most reactive methods remain stuck. Then, the adopted approach consists in constructing a navigation function in two dimensions from which the path is extracted. In the sense of the chosen criteria, it is optimal for a circular vehicle. Strategies are then put in place to adapt this algorithm to 4WS vehicles of rectangular shape, such as the central dual-path concept which allows to represent the trajectory of a mobile with three degrees of freedom in a two-dimensional space. Finally, other strategies and heuristics are introduced to optimize the performance of the planning algorithm and allow it to generate efficient maneuvers. Concerning the development of the controller, it is about choosing the evolution model which best reflects the behavior of the vehicle with respect to the dual-path that it must follow and then deducing the front and rear control laws. The 4WS bicycle model has shown itself to be very effective. This kinematic model makes it possible to easily introduce useful side-slip angles allowing to compensate the slippage of the tires on the ground, whether due to a lack of grip or an imperfect geometry of the axles. State feedback control laws are then synthesized and a strategy for managing the saturation of the actuators is proposed. Finally, this first controller is declined in a predictive version that provides a very stable tracking on real vehicles.The contributions were all evaluated in simulation and in full-scale experiments on the EZ10, an industrial 4WS electric shuttle. Finally, it turns out that the performances exceed initial expectations.

Le présent travail de thèse a pour but d'automatiser la détection des défauts de tissage, à l'aide d'un système informatisé fondé sur le traitement d'image. La structure du tissu, de par sa fabrication, est périodique par répétition de l'armure (dessin d'entrecroisement). L'apparition d'un défaut dans le tissu entraîne la destruction de cette périodicité. de ce fait, le défaut de tissage peut être détecté par la surveillance en continu de la structure du tissu pendant le tissage. Dans notre travail, les techniques de transformée rapide de Fourier et la corrélation croisée sont d'abord mises en œuvre, afin d'examiner les caractéristiques de régularité de la structure de l'image du tissu dans le domaine fréquentiel. Dans un deuxième temps, afin d'améliorer l'efficacité de la technique et d'éviter le problème d'erreur de détection, une opération de seuillage a été implémentée en utilisant un filtre de sélection de niveau. Au moyen de ce filtre, la technique mise en place est capable de détecter uniquement les défauts réels et de mettre en évidence leurs dimensions exactes. L'ensemble de cette procédure a été implémentée au moyen du progiciel Matlab ou Scilab. Puis l'ensemble des procédures a été mis en œuvre sur un tissu simulé, afin de comprendre le comportement du spectre de fréquences, de déterminer et d'optimiser les paramètres de détection les plus importants. Dans toutes ces procédures, le niveau de bruit a bien sûr été pris en compte. L'efficacité des procédures ayant été testée sur des tissus simulés dans un premier temps, elles ont été appliquées aux tissus sortant de machines à tisser. Ainsi, des échantillons contenant divers défauts ainsi que des échantillons écrus, unis ou de diverses couleurs ont pu être testés. Les techniques proposées ont aussi dans ces divers cas montré leur efficacité. En conclusion, un prototype fondé sur un dispositif de vision pour l'inspection des tissus sur métier à tisser en temps réel est proposé. / The purpose of this thesis is to automate the online detection of weaving defects by a computerized system based on image processing software. Obviously, fabric inspection has an importance to prevent risk of delivering inferior quality product. Until recently, the visual defect detection is still under taken offline and manually by humans with many drawbacks such as tiredness, boredom, and, inattentiveness. Fortunately, the continuous development in computer technology introduces the online automated fabric inspection as an effective alternative. Because the defect-free fabric has a periodic regular structure, the occurrence of a defect in the fabric breaks the regular structure. Therefore, the fabric defects can be detected by monitoring fabric structure. In our work, Fast Fourier Transform and Cross-correlation techniques, i.e. linear operations, are first implemented to examine the structure regularity features of the fabric image in the frequency domain. To improve the efficiency of the technique and overcome the problem of detection errors, further thresholding operation is implemented using a level selection filter. Through this filter, the technique is able to detect only the actual or real defects and highlight their exact dimensions. A software package such as Matlab or Scilab is used for this procedure. It is implemented firstly on a simulated plain fabric to determine the most important parameters during the process of defect detection and then to optimize each of them even considering noise. To verify the success of the technique, it is implemented on real plain fabric samples with different colours containing various defects. Finally, a vision-based fabric inspection prototype that could be accomplished on-loom to inspect the fabric under construction with 100% coverage is proposed.

No description available.