A análise em tempo real de pares de imagens estereoscópicas para extração de características dimensionais da cena tem apresentado crescente interesse, possibilitando robusta navegação robótica e identificação de objetos em cenários dinâmicos. A presente dissertação propõe um método que emprega a análise pixel a pixel e observação de janelas, em pares de imagens estereoscópicas, para extração de denso mapa de disparidades. A arquitetura de processamento proposta é única em sua constituição, misturando elementos de processamento concorrente e seqüencial. O algoritmo estrutura-se em processamento pipeline, permitindo sua implementação em dispositivos de lógica programável e obtenção de resultados em tempo real. / Real-time analysis of stereo images for extraction of dimensional features has been focus of great interest, providing means for autonomous robot navigation and identification of objects in dynamic environments. This work describes a method based in pixel-to-pixel and windows based matching analysis, in stereo images, for constructing dense disparity maps. The proposed processing structure is unique, mixing concurrent and sequential elements. Pipelines structure is employed, targeting implementation in FPGA devices and enabling real-time results.

Autonomous visual navigation algorithms for ground mobile robotic systems working in unstructured environments have been extensively studied for decades. Among these work, algorithm performance evaluations between different design configurations mainly involve the use of benchmark datasets with a limited number of real-world trails. Such evaluations, however, have difficulties to provide sufficient statistical power for performance quantification. In addition, they are unable to independently assess the algorithm robustness to individual realistic uncertainty sources, including the environment variations and processing errors. This research presents a quantitative approach to performance and robustness evaluation and optimisation of autonomous visual navigation algorithms, using large scale Monte-Carlo analyses. The Monte-Carlo analyses are supported by a simulation environment designed to represent a real-world level of visual information, using the perturbations from realistic visual uncertainties and processing errors. With the proposed evaluation method, a stereo vision based autonomous visual navigation algorithm is designed and iteratively optimised. This algorithm encodes edge-based 3D patterns into a topological map, and use them for the subsequent global localisation and navigation. An evaluation on the performance perturbations from individual uncertainty sources indicates that the stereo match error produces significant limitation for the current system design. Therefore, an optimisation approach is proposed to mitigate such an error. This maximises the Fisher information available in stereo image pairs by manipulating the stereo geometry. Moreover, the simulation environment is further updated in association with the algorithm design, which include the quantitative modelling and simulation of localisation error to the subsequent navigation behaviour. During a long-term Monte-Carlo evaluation and optimisation, the algorithm performance has been significantly improved. Simulation experiments demonstrate that the navigation of a 3-DoF robotic system is achieved in an unstructured environment, while possessing sufficient robustness to realistic visual uncertainty sources and systematic processing errors.

O problema de navegação de robôs móveis tem sido estudado ao longo de vários anos, com o objetivo de se construir um robô com elevado grau de autonomia. O aumento da autonomia de um robô móvel está relacionado com a capacidade de aquisição de informações e com a automatização de tarefas, tal como a construção de mapas de ambiente. Sistemas de visão são amplamente utilizados em tarefas de robôs autônomos devido a grande quantidade de informação contida em uma imagem. Além disso, sensores omnidirecionais catadióptricos permitem ainda a obtenção de informação visual em uma imagem de 360º, dispensando o movimento da câmera em direções de interesse para a tarefa do robô. Mapas de ambiente podem ser construídos para a implementação de estratégias de navegações mais autônomas. Nesse trabalho desenvolveu-se uma metodologia para a construção de mapas para navegação, os quais são a representação da geometria do ambiente. Contém a informação adquirida por um sensor catadióptrico omnidirecional estéreo, construído por uma câmera e um espelho hiperbólico. Para a construção de mapas, os processos de alinhamento, correspondência e integração, são efetuados utilizando-se métricas de diferença angular e de distância entre os pontos. A partir da fusão dos mapas locais cria-se um mapa global do ambiente. O processo aqui desenvolvido para a construção do mapa global permite a adequação de algoritmos de planejamento de trajetória, estimativa de espaço livre e auto-localização, de maneira a obter uma navegação autônoma. / The problem of mobile robot navigation has been studied for many years, aiming at build a robot with an high degree of autonomy. The increase in autonomy of a mobile robot is related to its capacity of acquisition of information and the “automation” of tasks, such as the environment map building. In this aspect vision has been widely used due to the great amount of information in an image. Besides that catadioptric omnidirectional sensors allow to get visual information in a 360o image, discharging the need of camera movement in directions of interest for the robot task. Environment maps may be built for an implementation of strategies of more autonomous navigations. In this work a methodology is developed for building maps for robot navigations, which are the representation of the environment geometry. The map contains the information received by a stereo omnidirectional catadioptric sensor built by a camera and a hyperbolic mirror. For the map building, the processes of alignment, registration and integration are performed using metric of angular difference and distance between the points. From the fusion of local maps a global map of the environment is created. The method developed in this work for global map building allows to be coupled with algorithms of path planning, self-location and free space estimation, so that autonomous robot navigation can be obtained.

O problema de navegação de robôs móveis tem sido estudado ao longo de vários anos, com o objetivo de se construir um robô com elevado grau de autonomia. O aumento da autonomia de um robô móvel está relacionado com a capacidade de aquisição de informações e com a automatização de tarefas, tal como a construção de mapas de ambiente. Sistemas de visão são amplamente utilizados em tarefas de robôs autônomos devido a grande quantidade de informação contida em uma imagem. Além disso, sensores omnidirecionais catadióptricos permitem ainda a obtenção de informação visual em uma imagem de 360º, dispensando o movimento da câmera em direções de interesse para a tarefa do robô. Mapas de ambiente podem ser construídos para a implementação de estratégias de navegações mais autônomas. Nesse trabalho desenvolveu-se uma metodologia para a construção de mapas para navegação, os quais são a representação da geometria do ambiente. Contém a informação adquirida por um sensor catadióptrico omnidirecional estéreo, construído por uma câmera e um espelho hiperbólico. Para a construção de mapas, os processos de alinhamento, correspondência e integração, são efetuados utilizando-se métricas de diferença angular e de distância entre os pontos. A partir da fusão dos mapas locais cria-se um mapa global do ambiente. O processo aqui desenvolvido para a construção do mapa global permite a adequação de algoritmos de planejamento de trajetória, estimativa de espaço livre e auto-localização, de maneira a obter uma navegação autônoma. / The problem of mobile robot navigation has been studied for many years, aiming at build a robot with an high degree of autonomy. The increase in autonomy of a mobile robot is related to its capacity of acquisition of information and the “automation" of tasks, such as the environment map building. In this aspect vision has been widely used due to the great amount of information in an image. Besides that catadioptric omnidirectional sensors allow to get visual information in a 360o image, discharging the need of camera movement in directions of interest for the robot task. Environment maps may be built for an implementation of strategies of more autonomous navigations. In this work a methodology is developed for building maps for robot navigations, which are the representation of the environment geometry. The map contains the information received by a stereo omnidirectional catadioptric sensor built by a camera and a hyperbolic mirror. For the map building, the processes of alignment, registration and integration are performed using metric of angular difference and distance between the points. From the fusion of local maps a global map of the environment is created. The method developed in this work for global map building allows to be coupled with algorithms of path planning, self-location and free space estimation, so that autonomous robot navigation can be obtained.

Ces travaux de thèse s’inscrivent dans un thème de recherche portant sur l’optimisation de la phase de conception et la préparation de la fabrication par estampage de pièces de formes complexes. Le préformage des renforts tissés secs est un enjeu important pour plusieurs procédés de production de pièces en matériaux composites tel que, par exemple, le procédé RTM (Resin Transfer Molding). Au cours de cette phase, la préforme est soumise à des déformations importantes. La connaissance du comportement du tissu sec est alors un enjeu majeur en vue de l’optimisation des procédés de mise en forme. Pour mettre en œuvre les renforts tissés, il est nécessaire de tenir compte de leurs caractéristiques intrinsèques aux différentes échelles, de leurs très grandes déformations en cisaillement et du comportement fortement orienté de ces matériaux. Un point important réside dans la détermination des orientations des renforts après formage. Face à la complexité de mise au point expérimentale de la mise en forme des renforts tissés, la simulation est un outil important pour l’optimisation de conception de pièces composites. Dans ce travail, une nouvelle approche hybride discrète non linéaire, basée sur l’association d’éléments continus hypoélastiques (comportement en cisaillement non linéaire) avec des connecteurs spécifiques de comportement non linéaire a été abordée. Elle permet de prédire les contraintes au niveau des fibres et de déterminer avec plus de précision, les angles de cisaillement en se basant sur la modification de l’orientation en grande déformation. En outre, elle permet d’analyser et de prévoir le comportement global du tissu à partir de sa structure interne. Le nombre de paramètres à identifier est faible et le temps de calcul est raisonnable. Cette approche a été programmée via une routine VUMAT et implémentée dans le code de calcul élément fini ABAQUS/Explicit. L’identification et la validation du modèle ont été effectuées en utilisant des essais de caractérisation standard des tissus. Les résultats de mise en forme des renforts tissés ont été comparés à des résultats expérimentaux.

Les influences du Soleil sur la Terre sont l'objet de récents développements en astrophysique regroupés sous le terme de météorologie de l'espace. Le vent solaire est une composante importante des interactions entre le Soleil et la Terre, et notamment le vent rapide issu des pôles. Puisqu'il est issu des régions polaires de la couronne, on comprend l'importance d'étudier ces régions. Dans cette thèse, on s'intéressera particulièrement à l'étude de ces régions polaires où se situent les plumes soupçonnées d'être à l'origine du vent solaire rapide. Les méthodes ainsi mises en oeuvre s'appliquent d'ailleurs tout aussi bien aux Éjections de Masse Coronale (CME). Pour ce faire, nous utilisons les données récoltées par les missions spatiales SoHO et STEREO. Ces missions fournissent des mesures de l'émission lumineuse du Soleil dans l'extrême ultra-violet (EUV) et des données coronographiques dans le visible. Il est important pour les reconstructions volumiques de la couronne de noter la présence de deux satellites identiques pour STEREO, semblables à SoHO. Ce qui nous permet d'avoir trois points de vue simultanés. Nous avons développé une méthode permettant à la fois de reconstruire l'émission de la couronne en trois dimensions mais également de prendre en compte l'évolution temporelle des plumes et de l'estimer, tout en tirant parti de la simultanéité des mesures selon différents points de vue. Cette avancée a été possible grâce au développement d'un modèle d'évolution des plumes polaires. Dans ce modèle, on suppose les plumes immobiles mais variant en intensité. En définissant par avance la localisation des plumes, on aboutit à un problème bilinéaire selon une composante statique et une composante temporelle. L'outil ainsi développé a été appliqué aux données EUV mesurées par SoHO et par STEREO ainsi que sur simulations. Les simulations ont révélé l'importance de prendre en compte les différents paramètres géométriques de ces missions spatiales. Le développement d'un code de projection et de rétroprojection adapté (et adaptable) ainsi qu'une étude minutieuse nous ont permis de définir les paramètres minimisant les artefacts géométriques de reconstruction. Enfin, la disponibilité de trois canaux de longueurs d'onde pour ces données EUV nous a permis d'effectuer une analyse spectrale des reconstructions en s'affranchissant de l'intégration sur la ligne de visée. En utilisant un modèle liant la répartition spectrale d'émission lumineuse et les paramètres du plasma tels que la densité et la température électronique, nous avons pu estimer ces deux grandeurs physiques pour chaque voxel des cartes tridimensionnelles de la couronne. En conclusion, la disponibilité prochaine de données de la mission SDO nous permettra d'affiner cette étude grâce à 8 canaux de longueurs d'onde EUV. Des développements dans l'estimation automatique des zones d'évolution temporelle et dans la reconstruction de CME sont également envisagés.

<p>Den här rapporten beskriver och utvärderar ett antal algoritmer för multisensordatafusion av radar och IR/TV-data på rådatanivå. Med rådatafusion menas att fusionen ska ske innan attribut- eller objektextrahering. Attributextrahering kan medföra att information går förlorad som skulle kunna förbättra fusionen. Om fusionen sker på rådatanivå finns mer information tillgänglig och skulle kunna leda till en förbättrad attributextrahering i ett senare steg. Två tillvägagångssätt presenteras. Den ena metoden projicerar radarbilden till IR-vyn och vice versa. Fusionen utförs sedan på de par av bilder med samma dimensioner. Den andra metoden fusionerar de två ursprungliga bilderna till en volym. Volymen spänns upp av de tre dimensionerna representerade i ursprungsbilderna. Metoden utökas också genom att utnyttja stereoseende. Resultaten visar att det kan vara givande att utnyttja stereoseende då den extra informationen underlättar fusionen samt ger en mer generell lösning på problemet.</p> / <p>This thesis describes and evaluates a number of algorithms for multi sensor fusion of radar and IR/TV data. The fusion is performed on raw data level, that is prior to attribute extraction. The idea is that less information will be lost compared to attribute level fusion. Two methods are presented. The first method transforms the radar image to the IR-view and vice versa. The images sharing the same dimension are then fused together. The second method fuses the original images to a three dimensional volume. Another version is also presented, where stereo vision is used. The results show that stereo vision can be used with good performance and gives a more general solution to the problem.</p>

Zinc xanthates polymerize propylene oxide into high polymer (PPO) with coordination mechanism. In order to identify structure and stereoisomerisms of this polymer, PPO was subjected to thermal and column fractionation. Obtained fractions were characterized by end-group analysis, cryoscopy, viscometry, IR and 13C-NMR spectroscopy, melting temperature. PPO is composed of a high molecular weight, stereoregular, crystallizable polymer (K-polymer) with low molecular weight (=500 g/mol) D-polymer. Presence of double bonds and hydroxyl terminals was interpreted as the product of an anionic mechanism. K-Polymers can be thermally fractionated on the basis of their melting temperature (Tm) rather than molecular weight (Mwt). It&amp / #8217 / s found that higher Tm fractions have lower Mwt, but they precipitate at higher temperatures than higher Mwt but lower Tm fractions. In column fractionation, K-polymers were deposited on glass beads from isooctane solution in a narrow temperature interval. Then the precipitated samples were split into a number of fractions by using again isooctane but at a higher temperature than the precipitation temperature by increasing residence time from 5 minutes to several hours. It&amp / #8217 / s found that rate of solubility is not controlled by molecular weight, but controlled by percentage crystallinity and Tm. Highest Tm polymers, with relatively higher Mwt showed faster rate of solution than that of lower Tm, lower Mwt but higher percent crystalline fractions. This discrepancy was accounted by suggesting a stereo-block structure where tactic blocks are bound each other with non-crystallizable atactic blocks. The mechanism of polymerization was also discussed in some detail.

The main purpose of this work is to investigate the behavior of the recently released by Microsoft company the Kinect sensor, which contains the properties that go beyond ordinary cameras. Normally, in order to create a 3D reconstruction of the scene two cameras are required. Whereas, the Kinect device, due to the properties of the Infrared projector and sensor allows to create the same type of the reconstruction using only one device. However, the depth images, which are generated by the Infrared laser projector and monochrome sensor in Kinect can contain undefined values. Therefore, in addition to other investigations this project contains an idea how to improve the quality of the depth images. However, the base aim of this work is to perform a reconstruction of the scene based on the color images using pair of Kinects which will be compared with the results generated by using depth information from one Kinect. In addition, the report contains the information how to check that all the performed calculations were done correctly. All  the algorithms which were used in the project as well as the achieved results will be described and discussed in the separate chapters in the current report.

This Master’s thesis studies the possibility of using image processing as a tool to facilitate vine management, in particular shoot counting and assessment of the grapevine canopy. Both are areas where manual inspection is done today. The thesis presents methods of capturing images and segmenting different parts of a vine. It also presents and evaluates different approaches on how shoot counting can be done. Within canopy assessment, the emphasis is on methods to estimate canopy density. Other possible assessment areas are also discussed, such as canopy colour and measurement of canopy gaps and fruit exposure. An example of a vine assessment system is given.