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Maneuvering through 3D structures nimbly is pivotal to the advancement of legged locomotion. However, few methods have been developed that can generate 3D gaits in those terrains and fewer if none can be generalized to control dynamic maneuvers. In this thesis, foot placement planning for dynamic locomotion traversing irregular terrains is explored in three dimensional space. Given boundary values of the center of mass' apexes during the gait, sagittal and lateral Phase Plane trajectories are predicted based on multi-contact and inverted pendulum dynamics. To deal with the nonlinear dynamics of the contact motions and their dimensionality, we plan a geometric surface of motion beforehand and rely on numerical integration to solve the models. In particular, we combine multi-contact and prismatic inverted pendulum models to resolve feet transitions between steps, allowing to produce trajectory patterns similar to those observed in human locomotion. Our contributions lay in the following points: (1) the introduction of non planar surfaces to characterize the center of mass' geometric behavior; (2) an automatic gait planner that simultaneously resolves sagittal and lateral feet placements; (3) the introduction of multi-contact dynamics to smoothly transition between steps in the rough terrains. Data driven methods are powerful approaches in absence of accurate models. These methods rely on experimental data for trajectory regression and prediction. Here, we use regression tools to plan dynamic locomotion in the Phase Space of the robot's center of mass and we develop nonlinear controllers to accomplish the desired plans with accuracy and robustness. In real robotic systems, sensor noise, simplified models and external disturbances contribute to dramatic deviations of the actual closed loop dynamics with respect to the desired ones. Moreover, coming up with dynamic locomotion plans for bipedal robots and in all terrains is an unsolved problem. To tackle these challenges we propose here two robust mechanisms: support vector regression for data driven model fitting and contact planning, and trajectory based sliding mode control for accuracy and robustness. First, support vector regression is utilized to learn the data set obtained through numerical simulations, providing an analytical solution to the nonlinear locomotion dynamics. To approximate typical Phase Plane behaviors that contain infinite slopes and loops, we propose to use implicit fitting functions for the regression. Compared to mainstream explicit fitting methods, our regression method has several key advantages: 1) it models high dimensional Phase Space states by a single unified implicit function; 2) it avoids trajectory over-fitting; 3) it guarantees robustness to noisy data. Finally, based on our regression models, we develop contact switching plans and robust controllers that guarantee convergence to the desired trajectories. Overall, our methods are more robust and capable of learning complex trajectories than traditional regression methods and can be easily utilized to develop trajectory based robust controllers for locomotion. Various case studies are analyzed to validate the effectiveness of our methods including single and multi step planning in a numerical simulation and swing foot trajectory control on our Hume bipedal robot. / text

Para o conhecimento da dinÃmica espacial das Ãreas de manguezais dos em dez complexos estuarinos da costa oeste cearense foram utilizadas imagens orbitais com resoluÃÃo espacial de 30m e imagens coloridas com resoluÃÃo de 2m, com aplicaÃÃo de tÃcnicas de sensoriamento remoto e tecnologia de Sistemas de InformaÃÃes GeogrÃfias (SIG). Ãs imagens do sensor TM do satÃlite LANDSAT 5, observadas por perÃodo de 23 anos, e Ãs ortofotos que recobrem a Ãrea objeto, foram aplicados procedimentos de classificaÃÃo orientada a objetos, tÃcnica que traduz o Estado da Arte para a extraÃÃo de informaÃÃes espaciais. A abordagem orientada a objeto delimita corpos singulares e homogÃneos a partir das informaÃÃes espectrais dos pixels, e de caracterÃsticas relacionadas à geometria e topologia dos objetos. Esse algoritmo foi desenvolvido para classificaÃÃo em imagens com altÃssima resoluÃÃo espacial, onde nÃo hà mistura espectral: os pixels possuem caracterÃsticas semelhantes a de seus vizinhos, enquanto que imagens de baixa e mÃdia resoluÃÃo espacial, os pixels contÃem informaÃÃes espectrais correspondentes a vÃrios objetos. Embora a base teÃrica/conceitual do mÃtodo de classificaÃÃo com orientaÃÃo a objeto priorize aplicaÃÃes sobre imagens de altÃssima resoluÃÃo espacial, a pesquisa teve por objetivo desenvolver estudos sobre imagens de mÃdia resoluÃÃo espacial para a quantificaÃÃo de Ãreas ocupadas por vegetaÃÃo de mangues dos estuÃrios da Costa Oeste cearense, entre os anos de 1985 e 2008. Com resultados da classificaÃÃo orientada a objeto, produzida em imagens de mÃdia resoluÃÃo espacial, foram realizadas anÃlises da dinÃmica espacial da Ãrea ocupada pelo sistema manguezal ao longo do recorte temporal estabelecido. A anÃlise da dinÃmica espacial entre o 1 e 2 perÃodos registrou incremento correspondente à variaÃÃo percentual de 3,43%, e para o intervalo entre o 2 e 3 perÃodos foi registrada a variaÃÃo de 6,35%. Jà a variaÃÃo observada entre os valores de Ãreas de mangues entre o 1 e 3 perÃodos, que corresponde ao recorte temporal de 1985 a 2008, corresponde a aproximadamente 10%. Em complementaÃÃo aos objetivos estabelecidos, os estudos foram concentrados na aquisiÃÃo de valores relativos à quantificaÃÃo, com acurÃcia, da vegetaÃÃo do ecossistema manguezal, mas obtidos sobre imagens ortorretificadas de alta resoluÃÃo, para a comparaÃÃo com dados publicados em trabalhos de outros autores, elaborados com tÃcnicas e metodologias distintas das empregadas na pesquisa. Para a validaÃÃo dos resultados da classificaÃÃo foram utilizadas as mesmas ortofotos, obtidas no ano de 2007, como referÃncia para a verificaÃÃo da Verdade Terrestre, com vistas à garantia da qualidade geomÃtrica e posicional das feiÃÃes de bosques de mangues identificadas. Enfatize-se que os resultados apresentaram discrepÃncias aceitÃveis para os objetivos estabelecidos. Por fim, as discrepÃncias observadas nos valores referentes aos complexos estuarinos pesquisados, comparados com outros trabalhos publicados estÃo associadas Ãs diferentes metodologias e tÃcnicas empregadas. / To the knowledge of the spatial dynamics of mangrove areas of estuarine complex on the west coast of Cearà were used satellite images with spatial resolution of 30m and images colored with a resolution of 2m, with application of remote sensing technology and geographic information systems (GIS). The sensor images of LANDSAT TM 5, observed for a period of 23 years, and orthophotos that cover the area object, classification procedures were applied object-oriented technique that reflects the state of the art for extracting spatial information. The object-oriented approach delimits natural and homogeneous bodies from the spectral information of pixels, and features related to geometry and topology of objects. This algorithm was developed for classification of images with high spatial resolution, where no spectral mixing: the pixels have similar characteristics to their neighbors, while images of low and medium spatial resolution, pixels contain spectral information corresponding to multiple objects. Although the theoretical / conceptual classification method with object orientation prioritize applications on images of high spatial resolution, the research aimed to develop studies on images of medium spatial resolution for quantification of areas occupied by vegetation mangrove estuaries Coast West Ceara, between the years 1985 and 2008. With results of object-oriented classification, produced in medium spatial resolution images were analyzed with the spatial dynamics of the area occupied by the system mangrove along the established time frame. The analysis of the spatial dynamics between the 1st and 2nd periods recorded an increase corresponding to the percentage change of 3.43%, and the interval between the 2nd and 3rd periods was recorded variation of 6.35%. However, the variation observed between the values of mangrove areas between the 1st and 3rd periods, corresponding to the time frame from 1985 to 2008, the rate recorded is around 10%. Complementing the established objectives, studies were concentrated on the acquisition of relative values to quantify with accuracy, the vegetation of the mangrove ecosystem, but obtained on high-resolution orthorectified images, for comparison with data published in works of other authors, drawn up techniques and different methodologies employed in the research. For validating the classification results were the same used orthophotos, obtained in 2007, as a reference for verifying the Truth Road, with a view to ensuring the quality of geometric and positional features of mangrove forests identified. Emphasize that the results showed discrepancies acceptable to the established objectives. Finally, the discrepancies observed in the values for the complex estuarine surveyed, compared with other published works are associated with different methodologies and techniques employed.

Made available in DSpace on 2014-07-29T15:32:08Z (GMT). No. of bitstreams: 1 Dissertacao Denis Castilho.pdf: 4748800 bytes, checksum: 7f46e4bf88b9d1c9b30c8ff7192f7c63 (MD5) Previous issue date: 2009-02-12 / Look Rialma and Ceres, two small towns of Goiás, is to stand in front of a problem space: the challenge is made to understand them in the context in which they operate: the territory of the state of Goiás. Therefore, the objective of this study was to understand the social and space dynamics of cities as part of the modernization of the state of Goiás. Therefore, we use the category territory to understand the city in its essence (founded in herself and in external logic). This process, which involves action, founded the movement, locations, especially the intersection of local variables and distant. The methodological procedures of the research were based on literature review and reading, with a survey of dissertations and theses on medium and small cities in the proposal to investigate the methodologies related to the theme. We did a survey of official data relating the to institutions for services, the productive infrastructure, to demographic dynamics and the financial system of these cities studied Ceres and Rialma with public institutions, such municipalities, the Secretary of State for Planning and Development - SEPLAN and institutes such as the IBGE, IPEA and the National Treasury Secretariat. Questionnaires were also used in public institutions of the health, education and establishments in retail. We conducted interviews with local authorities, secretaries, businessmen, workers, staff and students. Present Ceres / Rialma (proposed name for the case of sister city) through the landscape, which highlight elements that characterize the social order, the aspects visible, and the statistical nature of the landscape of these cities. The information of the object provided new questions. Seek to answer them by analysis of territorial formation which has highlighted the periods the modernization of territory of Goiás, the National Agricultural Colony of Goiás and the (re) functionalization of the Ceres / Rialma the input of the logic of globalization in the State of Goiás. We understand these municipalities through territory where they were analyzed the current socio-space, the position, function, and the new territorial division of work from the expansion of sugar cane by region. Despite the decrease in the area of influence of the urban core, from the growth of other cities (like Goianésia, Rubiataba and Itapaci), a specialization of the tertiary unit, especially in health Ceres, which highlights the role that city in a region strong stamp agriculture. Therefore, the function of the small nucleus urban Ceres / Rialma gives it a very unusual dynamic between small cities of the state, which made us review some concepts related to areas that are not metropolitan. Finally, we note that the structure assembled in these two cities from the performance of some social groups, especially those related to health in Ceres and the retail trade in Rialma. These actors show a group of entrepreneurs linked to the quick time. But there is also the subject of slow time, which remained under these conditions brings a dynamic that no longer hegemonic. The crossing time is found within the subjects themselves, which represent the dimension of space where they live, revealing a dynamic socio-space fruit of the action of a historical process and the locations, especially the lives of those who (re) produce there, the social relations of production / Olhar Ceres e Rialma, duas pequenas cidades goianas, é se colocar diante de uma problemática espacial: se remeter ao desafio de entendê-las no contexto em que se inserem: o território goiano. Portanto, o objetivo deste estudo foi o de compreender a dinâmica socioespacial desses municípios no âmbito da modernização de Goiás. Para tanto, recorremos ao território para entender a cidade em sua essência plena (fundada nela mesma e nas lógicas externas). Esse processo, que envolve a ação, fundamenta o movimento, as localizações, sobretudo o cruzamento das variáveis locais e distantes. Os procedimentos metodológicos da pesquisa foram baseados em revisão e leitura bibliográfica, onde realizamos, também, um levantamento de dissertações e teses sobre cidades médias e pequenas na proposta de averiguar as metodologias relacionadas ao tema. Fizemos um levantamento de dados oficiais referentes às instituições de serviços, à infra-estrutura produtiva, à dinâmica demográfica e ao sistema financeiro de Ceres e Rialma junto aos órgãos públicos desses municípios, à Secretaria de Estado do Planejamento e Desenvolvimento SEPLAN, e institutos como o IBGE, IPEA e Secretaria do Tesouro Nacional. Também foram aplicados questionários em instituições de saúde, educação, em órgãos públicos e estabelecimentos do comércio varejista. Realizamos entrevistas com autoridades locais, secretários, comerciantes, trabalhadores, funcionários e estudantes. Apresentamos Ceres/Rialma (nome proposto por se tratar de cidades irmãs) pela via da paisagem, onde destacamos elementos que dizem respeito à forma social, aos aspectos visíveis, estatísticos e à natureza da paisagem desses municípios. As informações do objeto proporcionaram novas questões. Procuramos respondê-las pela análise da formação territorial, onde foram evidenciados os períodos da modernização do território goiano, a Colônia Agrícola Nacional de Goiás e a (re)funcionalização de Ceres/Rialma pela entrada das lógicas da globalização em Goiás. Buscamos compreender esses municípios pela via do território, onde foram analisados a atual conjuntura socioespacial, a posição, a função e a nova divisão territorial do trabalho proveniente da expansão da cana-de-açúcar pela região. Apesar da diminuição da área de influência do núcleo urbano, proveniente do crescimento de outras cidades (como Goianésia, Rubiataba e Itapaci), houve uma especialização do aparelho terciário, especialmente da saúde em Ceres, o que evidencia o papel dessa cidade em uma região de forte cunho agrícola. Por conseguinte, a função do pequeno núcleo urbano Ceres/Rialma lhe confere uma dinâmica bastante incomum entre as pequenas cidades goianas, o que nos fez rever alguns conceitos referentes aos espaços não metropolitanos. Por último, verificamos que a estrutura montada nessas duas cidades decorre da atuação de alguns grupos sociais, sobretudo daqueles ligados à saúde em Ceres e ao comércio varejista em Rialma. Esses atores evidenciam um grupo de empreendedores ligados ao tempo rápido. Mas há, também, os sujeitos do tempo lento, que permaneceram nessas condições trazendo consigo uma dinâmica que deixou de ser hegemônica. O cruzamento de tempos é verificado no interior dos próprios sujeitos, que representam a dimensão do espaço onde vivem, revelando-nos uma dinâmica socioespacial fruto da ação, de um processo histórico e das localizações, sobretudo, da vida daqueles que (re)produzem ali, as relações sociais de produção

Made available in DSpace on 2015-03-13T17:10:40Z (GMT). No. of bitstreams: 1 FranciscoES_Geo.pdf: 1716748 bytes, checksum: dfde8ecb87503e2b9ea1d806c7611e0f (MD5) Previous issue date: 2006-06-15 / The public and private politics that was implemented in Natal, have always been attracting, great contingent of people in search of employments. However, not always, they can attend the migratory demands. Recently, Nova Parnamirim that is situated in the municipal district of Parnamirim - RN, due to proximity with Natal, it is passing for an intensive and accelerated occupation process impelled by the urban politics that created and they determined new diversities, leaning in the growth of the modern tertiary. In this context, Nova Parnamirim is suffering, along the time, substantial transformations in your espace, so much of nature social as environmental, that are affecting in the quality of your residents' life. This fact is mainly linked in the absence of an appropriate urban planning that have to be considered as an instrument norteador of the development of the city in its constant construction process. The study has as objective to analyze the social-space dynamics of the area and their implications, identifying the principal agents that promote and they benefit of that urbanization process. For the ccomplishment of this research it was executed bibliographical readings that turn of theoretical studies about the urban subjects and enviroments, besides field activities for the rising of the data investigated in the methodological approach / As pol?ticas p?blicas e privadas implementadas em Natal t?m atra?do grande contingente de pessoas em busca de empregos. Contudo, nem sempre, essas pol?ticas podem atender as demandas migrat?rias. Recentemente, Nova Parnamirim, situada no munic?pio de Parnamirim - RN, aliada ? proximidade com Natal, est? passando por um processo de ocupa??o intensivo e acelerado impulsionado pelas pol?ticas urbanas que criaram e determinaram novas diversidades, apoiadas no crescimento do terci?rio moderno. Nesse contexto, Nova Parnamirim vem sofrendo, ao longo do tempo, transforma??es substanciais no seu espa?o, tanto de natureza social quanto ambiental, que est?o se refletindo na qualidade de vida de seus moradores. Este fato est? ligado, principalmente, a aus?ncia de um planejamento urbano adequado que deve ser considerado como um instrumento norteador do desenvolvimento da cidade em seu constante processo de constru??o. O estudo tem como objetivo analisar a din?mica s?cio-espacial da ?rea e suas implica??es, identificando os principais agentes que promovem e se beneficiam desse processo de urbaniza??o. Para a realiza??o desta pesquisa, efetivou-se leituras bibliogr?ficas que versam de estudos te?ricos sobre as quest?es urbanas e ambientais, al?m de atividades de campo para o levantamento dos dados investigados na abordagem metodol?gica

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