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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Modelagem estatica e dinamica do amplificador a fibra dopada com erbio para sistemas WDM / Static and dynamic modeling of the erbium doped fiber amplifier to WDM system applications

Martin, Andrea Acunha 17 July 2007 (has links)
Orientador: Aldario Chrestani Bordonalli / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-09T17:35:37Z (GMT). No. of bitstreams: 1 Martin_AndreaAcunha_M.pdf: 1893415 bytes, checksum: bd7917b81e12d9fdade5bda5ff7489cb (MD5) Previous issue date: 2007 / Resumo: Neste trabalho, apresenta-se um estudo teórico das características de operação do amplificador a fibra dopada com érbio (EDFA ¿ erbium doped fiber amplifier), considerando-se regimes de operação estático e dinâmico, quando este é aplicado a sistemas de multiplexação por divisão em comprimento de onda. Após a introdução dos mecanismos que permitem a amplificação da luz no interior da fibra dopada, com destaque para a aplicação do bombeio em 980 nm, e a definição da topologia de amplificador a ser avaliada, partiu-se para o desenvolvimento das formulações que permitiram a análise do comportamento estático do amplificador. Primeiramente, a abordagem utilizada foi puramente monocanal, baseada na técnica da largura de banda equivalente, que incorporou uma nova proposta de rotina estável para a simulação do EDFA. Na seqüência, esta mesma rotina foi adaptada a um modelo estático reformulado e de aplicação multicanal, que passou a assumir a distribuição espectral da emissão espontânea amplificada. Numa etapa seguinte, uma segunda rotina de simulação multicanal foi desenvolvida a partir das modificações que o estudo do comportamento dinâmico do EDFA exigiu. Com os dados característicos de uma fibra dopada comercial, as diferentes rotinas de simulação foram utilizadas para avaliar parâmetros de operação do EDFA, tais como ganho de sinal, absorção de bombeio e figura de ruído, entre outros. Observou-se que os três métodos apresentaram, em geral e dentro de certos limites para as condições de contorno às quais o amplificador é submetido, concordância de resultados / Abstract: In this work, a theoretical study of the erbium doped fiber amplifier (EDFA) operational characteristics under static and dynamic conditions for application in wavelength division multiplexing systems is presented. After an introductory analysis of the physical properties that allow for light amplification inside the doped fiber, especially if 980 nm pumps are used, and the definition of the amplifier configuration to be considered, a formulation based on the static behavior of the amplifier was developed. The first approach was purely single channel and based on the equivalent bandwidth technique, which incorporated a new routine to guarantee stable solutions during EDFA simulation for different initial conditions. Then, this same convergence routine was used when the amplified spontaneous emission spectral distribution was considered to restructure the static model and to allow a multi-channel analysis. In a following stage, a second multi-channel simulation routine was conceived due to the modifications that the EDFA transient investigation required. By using the parameter of a commercial fiber, different simulation routines were used to evaluate the EDFA operational parameter, such as gain, pump absorption and noise figure. In general, it was observed that the three methods produced similar results within certain initial condition boundaries for the EDFA operation / Mestrado / Telecomunicações e Telemática / Mestre em Engenharia Elétrica
92

Modelagem da dinâmica espacial das mudanças na cobertura da terra na região portuária da Baixada Santista. / Spatial dynamics modeling of changes in land cover in port region of Baixada Santista.

Renata Sayuri Kawashima 08 December 2014 (has links)
Os padrões espaciais das alterações da cobertura da terra podem ser analisados a partir de modelagens da sua dinâmica espacial. Essas modelagens são capazes de descrever possíveis fatores responsáveis pelas mudanças territoriais, bem como viabilizar a estimativa de impactos futuros sobre o ambiente simulado. Considerando as pressões do setor de infraestrutura portuária sobre as configurações da forma de uso e planejamento do espaço na região portuária da Baixada Santista, tais como o aporte por áreas de retroporto, o armazenamento e o transporte de cargas, este estudo buscou desenvolver modelos dinâmicos da paisagem e investigar a relação entre as alterações na cobertura da terra e a infraestrutura de transportes na região portuária da Baixada Santista. A partir de produtos de sensoriamento remoto e da metodologia de modelagem dinâmica espacial baseada em autômatos celulares, foram gerados mapas simulados e cenários de prognósticos, com e sem projetos de expansão portuária para o ano de 2024. Os mapas simulados do ano de 1995 e 2005 foram semelhantes aos mapeamentos temáticos de cobertura da terra reais e apresentaram boa avaliação. Importante ressaltar que, apenas o mapa simulado de 2013 não previu as novas instalações portuárias, mesmo com a simulação rodando com a variável de novos empreendimentos operacionais em curto intervalo de tempo. O modelo estacionário em 2024 mostrou a expansão de áreas construídas em substituição, sobretudo, às áreas de campo. Não houve expansão de novas manchas de áreas construídas e isso condiz com a tendência de expansão de áreas urbanas seguindo as áreas já consolidadas e com infraestrutura implantada. Com relação à geração de modelos com os projetos de expansão portuária, tem-se a implantação de diversos empreendimentos ocupando parte da margem esquerda do estuário e áreas de retroporto próximas do arco viário da Baixada Santista. / Spatial patterns of change in land cover can be analyzed with spatial dynamic models. This modeling can indicate the driving factors of territorial changes as well as assess future impacts over the simulated environment. Considering the pressures of the port infrastructure sector over the land use and physical planning in the region of Baixada Santista, such as the demand for backport areas as well as for loads storage and transport, this study aims to develop dynamic models of the landscape and investigate the relationship between land cover change and the transport infrastructure in the port area of Santos. With the aid of remote sensing products and cellular automata based models, simulated maps of past landscapes and maps of future landscape scenarios were generated, both considering and disregarding port expansion projects for the year 2024.The simulated landscape maps of 1995 and 2005 were similar to the real ones, and hence, presented high fitness indices. It is important to mention that only the simulated map of 2013, could not foresee the new port facilities, even when the runs took into account the variables associated with the new operational ventures in a short period of time. The stationary model showed an expansion of built-up areas, mainly replacing former field areas. There was no occurrence of new patches of built-up areas and this trend is consistent with the expansion of urban areas nearby the already consolidated and established areas disposing of infrastructure facilities. Regarding the generation of future simulated scenarios taking into account the port expansion projects, they could well reproduce the implementation of several projects along part of the left bank of the estuary and nearby areas of the road ring of Baixada Santista.
93

Modelagem fuzzy funcional evolutiva participativa / Evolving participatory learning fuzzy modeling

Lima, Elton Mario de 07 April 2008 (has links)
Orientadores: Fernando Antonio Campos Gomide, Rosangela Ballini / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-12T14:32:10Z (GMT). No. of bitstreams: 1 Lima_EltonMariode_M.pdf: 1259231 bytes, checksum: 7a910e84bfb43d6c13b2deb8b6f511c2 (MD5) Previous issue date: 2008 / Resumo: Este trabalho propõe um modelo fuzzy funcional evolutivo que utiliza uma aplicação do aprendizado participativo para a construção de uma base de regras. O aprendizado participativo é um modelo de aprendizado baseado na noção de compatibilidade para a atualização do conhecimento do sistema. O aprendizado participativo pode ser traduzido em um algoritmo de agrupamento não supervisionado conhecido como agrupamento participativo. O algoritmo intitulado Aprendizado Participativo Evolutivo é proposto para construir um modelo fuzzy funcional evolutivo no qual as regras são obtidas a partir de um algoritmo de agrupamento não supervisionado. O algoritmo utiliza uma versão do agrupamento participativo para a determinação de uma base de regras correspondente ao modelo funcional do tipo Takagi-Sugeno evolutivo. A partir de uma noção generalizada, o modelo proposto é aplicado em problemas de previsão de séries temporais e os resultados são obtidos para a conhecida série Box-Jenkis, além da previsão de uma série de carga horária de energia elétrica. Os resultados são comparados com o modelo Takagi-Sugeno evolutivo que utiliza a noção de função potencial para agrupar os dados dinâmicamente e com duas abordagens baseadas em redes neurais. Os resultados mostram que o modelo proposto é eficiente e parcimonioso, abrindo potencial para aplicações e estudos futuros. / Abstract: This work introduces an approach to develop evolving fuzzy rule-based models using participatory learning. Participatory learning assumes that learning and beliefs about a system depend on what the learning mechanism knows about the system itself. Participatory learning naturally augments clustering and yields an e_ective unsupervised fuzzy clustering algorithms for on-line, real time domains and applications. Clustering is an essential step to construct evolving fuzzy models and plays a key role in modeling performance and model quality. A least squares recursive approach to estimate the consequent parameters of the fuzzy rules for on-line modeling is emphasized. Experiments with the classic Box-Jenkins benchmark are conducted to compare the performance of the evolving participatory learning with the evolving fuzzy system modeling approach and alternative fuzzy modeling and neural methods. The experiments show the e_ciency of evolving participatory learning to handle the benchmark problem. The evolving participatory learning method is also used to forecast the average hourly load of an electric generation plant and compared against the evolving fuzzy system modeling using actual data. The results confirm the potential of the evolving fuzzy participatory method to solve real world modeling problems. / Mestrado / Automação Industrial / Mestre em Engenharia Elétrica
94

Modélisation dynamique d’un système couplé pompe à chaleur – stockage thermique par matériaux à changement de phase : approche systémique et validation expérimentale / Dynamic modeling of a heat pump coupled to a PCM storage tank - systemic approach and experimental validation

Wu, Jing 08 October 2015 (has links)
Dans le domaine de la réfrigération des bâtiments, le couplage d'une pompe à chaleur (PAC) avec un stockage d'énergie thermique est un moyen significatif pour en réduire le coût de fonctionnement énergétique et pour mieux dimensionner les équipements. Un prototype de ce système couplé avec un stockage thermique par MCP (Matériaux à Changement de Phase) est construit et mis en oeuvre dans le cadre du projet ANR ACLIRSYS (Commande avancée des systèmes de réfrigération à faible inertie). L'objectif de cette thèse est d'en proposer un modèle dynamique en vue de sa commande. Dans les échangeurs de la PAC, le fluide frigorigène peut être vapeur, liquide ou un mélange des deux tandis que le MCP du stock peut être solide, liquide ou un mélange des deux. Par conséquent, un modèle de type hybride est nécessaire pour tenir compte des différentes configurations possibles afin de résoudre les équations de bilan de masse et d'énergie dont les expressions diffèrent en fonction de ces configurations. Dans ce travail, des modèles statiques sont utilisés pour le compresseur et le détendeur de la PAC, et les modèles des échangeurs de la PAC et du stock sont basés sur une représentation des écoulements par une cascade de Réacteurs Parfaitement Agités Continues (RPAC). Le mécanisme de commutation entre les diverses configurations est conçu pour garantir la continuité de l'évolution simulée du système. Cette commutation est effectuée par des opérations matricielles, ce qui permet d'aboutir à une représentation globale et très compacte du système. Les propriétés thermodynamiques du fluide frigorigène et leurs dérivées partielles sont déterminées de façon analytique à l'aide d'une équation d'état. Deux versions du modèle du stock sont proposées. Une version simplifiée du modèle de surfusion et une version plus détaillée basée sur la méthode des bilans de population. Des données expérimentales recueillies sur le prototype ont permis de valider le modèle développé. Des expérimentations en régime transitoire ont été réalisées en faisant varier les conditions opératoires. Ces données concernent le fonctionnement de la PAC seule, du stock seul et du système couplé. Un bon accord a été obtenu entre les résultats numériques et les données expérimentales / In the area of buildings refrigeration, the use of thermal energy storage coupled with heat pump is a significant way for reducing the operating costs and optimizing the design of equipment. A prototype of refrigeration-PCM (Phase Change Material) energy storage system is built and implemented within the framework of the project ACLIRSYS (Advanced Control for Low Inertia Refrigeration Systems), funded by the French National Research Agency. The objective of my PhD thesis is to propose a dynamical physical model for the complete system. Within the evaporator and condenser of the heat pump, the refrigerant can be liquid, vapor or mixture of both, while the storage media can be solid, liquid or a mixture of both. Therefore, it is necessary to consider the discrete events associated to phase changes in order to solve the energy and mass balances in different configurations. In this work, static models are used for the compressor and the expansion valve of the heat pump. The heat exchangers of the heat pump and the storage models are based on a representation of the fluid flows by a cascade of Continuous Stirred Tank Reactors (CSTRs). In order to assure the continuity of system evolution, the switching mechanism between different configurations is established. This switching is performed by matrix operations, which permit to achieve a global and very compact representation of the system. The thermodynamic properties of the refrigerant and their partial derivatives are analytically determined by using an equation of state. Two versions of the model for the storage are proposed. A simplified version where the supercooling is assumed to take place at a constant temperature and a more detailed version based on the population balance equations. Experimental data from the prototype has been used to validate the developed model. Experiments in transient states were performed by varying the operating conditions. These date relate to the functioning of the heat pump alone, the storage alone and the coupled system. A very good agreement between the numerical results and experimental data was obtained
95

MODELAGEM DINÂMICA PARA SIMULAÇÃO DE MUDANÇAS NA COBERTURA FLORESTAL DAS SERRAS DO SUDESTE E CAMPANHA MERIDIONAL DO RIO GRANDE DO SUL / DYNAMIC MODELING FOR CHANGES SIMULATIONS IN THE FOREST COVER AT THE SERRAS DO SUDESTE AND CAMPANHA MERIDIONAL FROM RIO GRANDE DO SUL STATE

Benedetti, Ana Caroline Paim 02 June 2010 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Significant processes of conversion in the land use patterns have been verified in the State of Rio Grande do Sul due to the incorporation of forest areas during the last years. In this conception, this work aims to establish the methodological guidelines to analyze the dynamics of these patterns in the Serras do Sudeste and Campanha Meridional, which are micro regions located in the southern part of the State. Thematic maps from the years 2000, 2004 and 2008 were elaborated through the product NDVI (Normalized Difference Vegetation Index) from the MODIS sensor in a way to relate this index to the land use classes. The maps that we elaborated were used to drive a dynamic model, which made it possible to quantify, through the use of Markov model, the conversion rates between classes. The simulation designed using the probabilistic method weighs-of-evidence, and allowed to assess the role of influential variables in the forest cover changes of both micro regions. The main results are simulations based on the paradigm of Cellular Automata (CA), in which the forest areas are quantified and spatially distributed until the year 2016. The predictions modeled, based on the considered variables, indicate that the forest will expand over spaces previously allocated to agricultural activities and to extensive grazing of cattle, either with the introduction of exotic species or by means of regeneration. The forest cover in Serras do Sudeste will increase from 8,6% to 16,2% by the end of the period. In Campanha Meridional the increase will be from 11,1% to 12,5% and, in both micro regions, the expansion will tend to stabilize within the observed period. / Processos significativos de conversão nos padrões de uso da terra têm sido verificados no Rio Grande do Sul devido à incorporação de áreas florestais nos últimos anos. Nessa concepção, este trabalho tem como objetivo estabelecer diretrizes metodológicas para analisar a dinâmica desses padrões nas Serras do Sudeste e Campanha Meridional, microrregiões pertencentes à Metade Sul do Estado. Mapas temáticos dos anos de 2000, 2004 e 2008 foram elaborados a partir do produto NDVI (Índice de Vegetação por Diferença Normalizada) do sensor MODIS, de forma a relacionar este índice às classes de uso da terra. Os mapas elaborados serviram para alimentar um modelo dinâmico, o qual possibilitou quantificar, através de matrizes Markovianas, as taxas de conversão entre as classes. A simulação foi concebida através do método probabilístico pesos de evidência, o qual permitiu inferir sobre a contribuição das variáveis influentes nas mudanças na cobertura florestal das duas microrregiões. Os principais resultados constituem simulações baseadas no paradigma de Autômatos Celulares (AC), nas quais são quantificadas e distribuídas espacialmente as áreas florestais até o ano de 2016. Os prognósticos modelados, com base nas variáveis analisadas, indicam que a floresta deve ocupar espaços anteriormente destinados às atividades agrícolas e ao pastoreio extensivo do gado, tanto pela introdução de espécies exóticas como pelo estabelecimento da regeneração. A cobertura florestal na microrregião Serras do Sudeste passará de 8,6% para 16,2% ao fim do período. Na Campanha Meridional o acréscimo será de 11,1% para 12,5%, sendo observadas, nas duas microrregiões, tendências à estabilidade dessa expansão.
96

Modélisation dynamique et suivi de tumeur dans le volume rénal / Dynamic modeling and tumor tracking for the kidney

Leonardi, Valentin 13 November 2014 (has links)
Ce travail de thèse porte sur la modélisation dynamique 3D du rein et le suivi d’une tumeur de cet organe. Il s’inscrit dans le projet KiTT (Kidney Tumor Tracking) qui regroupe des chercheurs issus de plusieurs domaines : la modélisation géométrique, la radiologie et l’urologie. Le cadre de cette thèse suit une tendance de mini-invasivité des gestes chirurgicaux observée ces dernières années (HIFU, coelioscopie). Sa finalité est d’aboutir à un nouveau protocole de destruction de tumeurs rénales totalement non-invasif, par la diffusion d’agents physiques (ondes d’ultrasons) à travers la peau et focalisés sur la tumeur. Devant le mouvement et la déformation que le rein présente au cours du cycle respiratoire, la problématique de ces travaux de recherche est de connaître en permanence la position de la tumeur afin d’ajuster à moyen terme la diffusion des ondes en conséquence. / This Ph.D. thesis deals with the 3D dynamic modeling of the kidney and tracking a tumor of this organ. It is in line with the KiTT project (Kidney Tumor Tracking) which gathers researchers from different fileds: geometric modeling, radiology and urology. This work arised from the tendency of nowadays surgical gestures to be less and less invasive (HIFU, coelioscopy). Its goal is to result in a totally non-invasive protocol of kidney tumors eradication by transmitting ultrasound waves through the skin without breaking in it. As the kidney presents motions and deformations during the breathing phase, the main issue is to know the kidney and tumor positions at any time in order to adjust the waves accordingly.
97

A simulation-based approach to test the performance of large-scale real time software systems

Waqas, Muhammad January 2020 (has links)
Background: A real-time system operates with time constraints, and its correctness depends upon the time on which results are generated. Different industries use different types of real-time systems such as telecommunication, air traffic control systems, generation of power, and spacecraft system. There is a category of real-time systems that are required to handle millions of users and operations at the same time; those systems are called large scale real-time systems. In the telecommunication sector, many real-time systems are large scale, as they need to handle millions of users and resources in parallel. Performance is an essential aspect of this type of system; unpredictable behavior queue cost millions of dollars for telecom operators in a matter of seconds. The problem is that existing models for performance analysis of these types of systems are not cost-effective and require lots of knowledge to deploy. In this context, we have developed a performance simulator tool that is based on the XgBoost, Random Forest, and Decision Tree modeling. Objectives: The thesis aims to develop a cost-effective approach to support the analysis of the performance of large-scale real-time telecommunication systems. The idea is to develop and implement a solution to simulate the telecommunication system using some of the most promising identified factors that affect the performance of the system. Methods: We have performed an improvement case study in Ericsson. The identification of performance factors is found through a dataset generated in a performance testing session, the investigation conducted on the same system, and unstructured interviews with the system experts. The approach was selected through a literature review. Validation of the Performance Simulator performed through static analysis and user feedback received from the questionnaire. Results: The results show that Performance Simulator could be helpful to performance analysis of large-scale real-time telecommunication systems. Performance Simulator ability to endorse performance analysis of other real-time systems is a collection of multiple opinions. Conclusions: The developed and validated approach demonstrates potential usefulness in performance analysis and can benefit significantly from further enhancements. The specific amount of data used for training might impact the generalization of the research on other real-time systems. In the future, this study can establish with more numbers of input on real-time systems on a large scale.
98

A novel approach for experimental identification of vehicle dynamic parameters

Yao, Di, Ulbricht, Philipp, Tonutti, Stefan, Büttner, Kay, Prokop, Günther 18 May 2022 (has links)
Pervasive applications of the vehicle simulation technology are a powerful motivation for the development of modern automobile industry. As basic parameters of road vehicle, vehicle dynamic parameters can significantly influence the ride comfort and dynamics of vehicle, and therefore have to be calculated accurately to obtain reliable vehicle simulation results. Aiming to develop a general solution, which is applicable to diverse test rigs with different mechanisms, a novel model-based parameter identification approach using optimized excitation trajectory is proposed in this paper to identify the vehicle dynamic parameters precisely and efficiently. The proposed approach is first verified against a virtual test rig using a universal mechanism. The simulation verification consists of four sections: (a) kinematic analysis, including the analysis of forward/inverse kinematic and singularity architecture; (b) dynamic modeling, in which three kinds of dynamic modeling method are used to derive the dynamic models for parameter identification; (c) trajectory optimization, which aims to search for the optimal trajectory to minimize the sensitivity of parameter identification to measurement noise; and (d) multibody simulation, by which vehicle dynamic parameters are identified based on the virtual test rig in the simulation environment. In addition to the simulation verification, the proposed parameter identification approach is applied to the real test rig (vehicle inertia measuring machine) in laboratory subsequently. Despite the mechanism difference between the virtual test rig and vehicle inertia measuring machine, this approach has shown an excellent portability. The experimental results indicate that the proposed parameter identification approach can effectively identify the vehicle dynamic parameters without a high requirement of movement accuracy.
99

Jambe Humanoïde Hydraulique pour HYDROïD / HYDROïD Humanoid Hydraulic Leg

Ibrahim, Ahmed Abdellatif Hamed 18 July 2018 (has links)
Le corps humain a toujours été une source d’inspiration pour les ingénieurs et les scientifiques de tous les domaines dans le monde entier. L’un des sujets les plus intéressants de la dernière décennie a été les robots humanoïdes. Les robots humanoïdes représentent les systèmes robotiques les plus complexes. Ils offrent une plus grande mobilité dans les terrains accidentés et non structurés que les véhicules à roues normaux. À l’avenir, les robots humanoïdes devraient être employés pour une variété de tâches dangereuses dans des domaines tels que les opérations de sauvetage, l’assistance aux personnes âgées, l’éducation et le déminage humanitaire. Le travail réalisé dans cette thèse est réalisé sur le robot hydraulique humanoïde HYDROïD, un humanoïde à commande hydraulique avec 52 degrés de liberté actifs, conçu pour exécuter des tâches très dynamiques comme la marche, la course et le saut. robot puisque les actionneurs hydrauliques ont un excellent rapport poids/puissance et absorbent naturellement les pics de force d’impact lors des différentes activités. L'objectif de cette thèse est de contribuer au développement des mécanismes robotiques de la cheville et du genou avec une dynamique élevée. Un nouveau mécanisme de cheville est développé afin de pallier les inconvénients des performances réalisées avec l’ancien mécanisme de cheville d'origine. Des taux de fuite et de frottement plus faibles sont obtenus en plus d’une optimisation de pression pour les articulations de la cheville. De plus, une nouvelle solution pour optimiser le poids des actionneurs hydrauliques est appliquée sur le mécanisme du genou du robot.Une telle solution comprend l’utilisation de la technologie des matériaux composites légers pour atteindre un poids et une performance optimisés pour le joint. Afin d’appliquer des méthodologies de contrôle sur les mécanismes de la cheville et du genou, un modèle géométrique inverse pour les deux mécanismes est présenté. Le contrôle de position est utilisé pour contrôler les angles des articulations de la cheville et les mécanismes du genou. Enfin, les conclusions et les perspectives d’avenir sont présentées dans le dernier chapitre. / Human body has always been an inspiration for engineers and scientists from all fields all over the world. One of the most interesting topics in the last decade was humanoid robots. Humanoid robots represent the most complex robotic systems. They provide greater mobility in rough and unstructured terrain than the normal wheeled vehicles. In the future, humanoid robots are expected to be employed for a variety of dangerous tasks in fields like rescue operations, assisting elderly people, education and humanitarian demining. The work achieved in this dissertation is performed on the humanoid hydraulic robot HYDROïD. It is hydraulically actuated humanoid featuring 52 active degrees of freedom and is designed to perform highly dynamic tasks like walking, running and jumping. Hydraulic power was chosen for this robot since hydraulic actuators have an excellent power to weight ratio and naturally absorb impact force peaks during different activities. The objective of this dissertation is to contribute toward the development of ahighly dynamic robotic ankle and knee mechanisms. A new ankle mechanism islooked for in order to tackle the drawbacks raised by the performances achievedwith the original old ankle mechanism. Lower leakage and friction rates areachieved in addition to a pressure optimization for the ankle joints. Moreover, anew solution for optimizing the weight of hydraulic actuators is applied on theknee mechanism of the robot. Such solution includes the usage of light compositematerial technology to achieve optimized weight and performance for the joint.In order to apply control methodologies on the ankle and knee mechanisms,inverse geometrical model for the both mechanism are presented. Position controlis used to control the joints angles of the ankle and the knee mechanisms. Finally,the conclusions and the future perspectives are presented in the last chapter.
100

Compliant robotic arms for inherently safe physical human-robot interaction

She, Yu January 2018 (has links)
No description available.

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