Continuum robots mimic the principle of a special biological structure known as the muscular hydrostat. These robots have an ability to bend at any location on along its backbone and have potential applications in disaster relief, medical surgeries and nuclear waste disposal. This thesis presents the modeling and verification of a multi-section continuum robot by applying the Cosserat theory of rods. Next, 2D verification is performed on a continuum robot based on a backbone composed of a nickel titanium alloy. In addition, the thesis develops the theoretical foundations for a cable-driven continuum robot by studying the effects of cable guide mass which cause additional deformation of the robot The results of this thesis show that the multi-section model is accurate within 3.4% in predicting the Cartesian tip coordinates, and the model with the cable guides accurate within 1.26% error in predicted versus the observed Cartesian tip coordinates of the backbone.

Observando-se as diversas aplicações de robôs na área de serviços é possível perceber uma crescente busca por manipulação de ferramentas em lugares elevados utilizando dispositivos robóticos, visto que tais tarefas exigem a utilização de diversos equipamentos de segurança e apresentam um alto risco à presença humana. Os exemplos mais comuns desse tipo de tarefa são: inspeção de: máquinas de grande porte, tanques de armazenamento, silos, postes, linhas de transmissão e distribuição de energia elétrica, etc. Com o intuito de aplicar robôs a essas tarefas, e consequentemente aumentar a segurança e eficiência dessas operações, foi realizado, primeiramente neste trabalho, um estudo sobre as classes de robôs manipuladores existentes. Para tanto adotou-se uma classificação que separa os robôs de acordo com o número de juntas, o que gera uma divisão em três diferentes grupos, robôs discretos, robôs do tipo serpente e robôs contínuos. Ao analisar as três classes, observa-se que os robôs contínuos possuem mais graus de liberdade que os outros grupos, apresentando como estrutura uma coluna vertebral continuamente deformável, que em oposição aos tradicionais manipuladores robóticos elo/junta/elo, possuem mecanismos mais simplificados, controle menos complexo devido ao menor número de atuadores e podem interagir com obstáculos encontrados em seu ambiente sem criar grandes forças de contato. Ao utilizar configurações extrínsecas, ou seja, posicionando os atuadores fora da estrutura do robô, e transmitindo o movimento utilizando cabos, é possível construir robôs com alta isolação elétrica, o que é de grande utilidade para operações que envolvem tarefas nas proximidades de redes elétricas de alta tensão. Apesar das diversas vantagens, não foram encontradas na literatura aplicações de robôs contínuos na realização de tarefas em alturas elevadas. Levando em consideração as vantagens oferecidas pelos robôs contínuos, este trabalho propõe o estudo e a aplicação de um robô do tipo contínuo que possua uma arquitetura mais adequada para realizar trabalhos a alturas elevadas. Com o intuito de demonstrar as vantagens oferecidas por essa arquitetura, será realizado um estudo de caso no qual o objeto a ser inspecionado são as cruzetas de madeira em postes de distribuição de energia elétrica. Em uma segunda etapa, elabora-se o projeto mecânico do robô contínuo proposto, onde são detalhados os mecanismos propostos e são feitas simulações utilizando o método dos elementos finitos para analisar o comportamento da estrutura quando submetida a carregamentos. Em uma terceira etapa, adotando-se uma estratégia de controle seqüencial é elaborado o projeto de controle. Em uma ultima etapa, com o intuito de analisar o funcionamento do robô é construído um protótipo, com o qual são feitos os testes. / Among several applications of robots in the service field, it is possible to percept an increasing interest in manipulate tools in higher positions using automatic devices, due to the fact that such activities are high risked operations and demands the use of several safety equipments. The most common examples of this kind of activity are the inspection of machines, silos, electrical distribution poles, etc. With the aim of apply robots to these activities and increase the safety and efficiency in these operations, as a first step in this work is done the study of different kinds of manipulators. Adopting a classification based on the number of joints, it is possible to separate robots in three different classes: discrete robots, snake-like robots and continuum robots. By analyzing these classes, it is possible to say that continuum robots have more degrees of freedom than the robots of others groups; Compared with the classic discrete robots, continuum robots have simplified mechanisms, simpler control scheme due to the small number of actuators and, in the case of an obstacle, they can contour the obstacle without generating high contact forces. By positioning the actuators out of the robot structure and transferring the motion using cables, i.e., adopting an extrinsic actuation, it is possible to build continuum robots with high electric insulation that is important in applications in which the robot must work near of an electrical distribution network. Despite these advantages, no previous works concerning the use of continuum robots to work in higher positions were found in the literature. Considering the advantages offered by continuum robots, this work proposes a study and application of a continuum robot that uses a more suitable architecture to work in higher positions. Aiming to demonstrate the advantages provided by this architecture, It will be used a case study, in which, the object to be inspected is the wood cross-arms of an electrical poles used in the electrical distribution networks. In a second step, it is done the mechanical project of the robot, where the proposed mechanisms are explained and structural simulations using the finite element method are performed in order to analyze how the structure would react to loads. In a third step, by adopting a strategy of sequential control, it is done the control project. In the last step, with the aim of analyze the robot in practical situation, a prototype is built, which is used to perform the tests.

Observando-se as diversas aplicações de robôs na área de serviços é possível perceber uma crescente busca por manipulação de ferramentas em lugares elevados utilizando dispositivos robóticos, visto que tais tarefas exigem a utilização de diversos equipamentos de segurança e apresentam um alto risco à presença humana. Os exemplos mais comuns desse tipo de tarefa são: inspeção de: máquinas de grande porte, tanques de armazenamento, silos, postes, linhas de transmissão e distribuição de energia elétrica, etc. Com o intuito de aplicar robôs a essas tarefas, e consequentemente aumentar a segurança e eficiência dessas operações, foi realizado, primeiramente neste trabalho, um estudo sobre as classes de robôs manipuladores existentes. Para tanto adotou-se uma classificação que separa os robôs de acordo com o número de juntas, o que gera uma divisão em três diferentes grupos, robôs discretos, robôs do tipo serpente e robôs contínuos. Ao analisar as três classes, observa-se que os robôs contínuos possuem mais graus de liberdade que os outros grupos, apresentando como estrutura uma coluna vertebral continuamente deformável, que em oposição aos tradicionais manipuladores robóticos elo/junta/elo, possuem mecanismos mais simplificados, controle menos complexo devido ao menor número de atuadores e podem interagir com obstáculos encontrados em seu ambiente sem criar grandes forças de contato. Ao utilizar configurações extrínsecas, ou seja, posicionando os atuadores fora da estrutura do robô, e transmitindo o movimento utilizando cabos, é possível construir robôs com alta isolação elétrica, o que é de grande utilidade para operações que envolvem tarefas nas proximidades de redes elétricas de alta tensão. Apesar das diversas vantagens, não foram encontradas na literatura aplicações de robôs contínuos na realização de tarefas em alturas elevadas. Levando em consideração as vantagens oferecidas pelos robôs contínuos, este trabalho propõe o estudo e a aplicação de um robô do tipo contínuo que possua uma arquitetura mais adequada para realizar trabalhos a alturas elevadas. Com o intuito de demonstrar as vantagens oferecidas por essa arquitetura, será realizado um estudo de caso no qual o objeto a ser inspecionado são as cruzetas de madeira em postes de distribuição de energia elétrica. Em uma segunda etapa, elabora-se o projeto mecânico do robô contínuo proposto, onde são detalhados os mecanismos propostos e são feitas simulações utilizando o método dos elementos finitos para analisar o comportamento da estrutura quando submetida a carregamentos. Em uma terceira etapa, adotando-se uma estratégia de controle seqüencial é elaborado o projeto de controle. Em uma ultima etapa, com o intuito de analisar o funcionamento do robô é construído um protótipo, com o qual são feitos os testes. / Among several applications of robots in the service field, it is possible to percept an increasing interest in manipulate tools in higher positions using automatic devices, due to the fact that such activities are high risked operations and demands the use of several safety equipments. The most common examples of this kind of activity are the inspection of machines, silos, electrical distribution poles, etc. With the aim of apply robots to these activities and increase the safety and efficiency in these operations, as a first step in this work is done the study of different kinds of manipulators. Adopting a classification based on the number of joints, it is possible to separate robots in three different classes: discrete robots, snake-like robots and continuum robots. By analyzing these classes, it is possible to say that continuum robots have more degrees of freedom than the robots of others groups; Compared with the classic discrete robots, continuum robots have simplified mechanisms, simpler control scheme due to the small number of actuators and, in the case of an obstacle, they can contour the obstacle without generating high contact forces. By positioning the actuators out of the robot structure and transferring the motion using cables, i.e., adopting an extrinsic actuation, it is possible to build continuum robots with high electric insulation that is important in applications in which the robot must work near of an electrical distribution network. Despite these advantages, no previous works concerning the use of continuum robots to work in higher positions were found in the literature. Considering the advantages offered by continuum robots, this work proposes a study and application of a continuum robot that uses a more suitable architecture to work in higher positions. Aiming to demonstrate the advantages provided by this architecture, It will be used a case study, in which, the object to be inspected is the wood cross-arms of an electrical poles used in the electrical distribution networks. In a second step, it is done the mechanical project of the robot, where the proposed mechanisms are explained and structural simulations using the finite element method are performed in order to analyze how the structure would react to loads. In a third step, by adopting a strategy of sequential control, it is done the control project. In the last step, with the aim of analyze the robot in practical situation, a prototype is built, which is used to perform the tests.

This thesis proposes a general and unified methodological framework suitable for studying the locomotion of a wide range of robots, especially bio-inspired. The objective of this thesis is twofold. First, it contributes to the classification of locomotion robots by adopting the mathematical tools developed by the American school of geometric mechanics.Secondly, by taking advantage of the recursive nature of the Newton-Euler formulation, it proposes numerous efficient tools in the form of computational algorithms capable of solving the external direct dynamics and the internal inverse dynamics of any locomotion robot considered as a mobile multi-body system. These generic tools can help the engineers or researchers in the design, control and motion planning of manipulators as well as locomotion robots with a large number of internal degrees of freedom. The efficient algorithms are proposed for discrete and continuous robots. These methodological tools are applied to numerous illustrative examples taken from the bio-inspired robotics such as snake-like robots, caterpillars, and others like snake-board, etc.

Continuum robots are biologically inspired robots that capture the extraordinary abilities of biological structures such as elephant trunks, octopus tentacles, and mamma-lian tongues. They are given the term continuum robots due to their ability to bend conti-nuously rather than at specific joints such as with traditional rigid link robots. They are used in applications such as search and rescue operations, nuclear reactor repairs, colo-noscopies, minimal invasive surgeries, and steerable needles. In this thesis, a model that predicts the shape of a continuum robot is presented and verified. A verification system to verify the validity and accuracy of the model is presented which allows easy and accu-rate measurement of a continuum robot tip position. The model was verified against a flexible rod, the core component of a continuum robot, resulting in an accuracy of 0.61%. Finally, this thesis introduces a novel robot design, consisting of a single rod for the backbone which can be manipulated by applying external forces and torques.

L’utilisation de systèmes robotiques pour la navigation dans des zones confinées pose des défis intéressants sur les thèmes de conception, de modélisation et de commande, particulièrement complexes pour les applications médicales. Dans ce contexte, nous introduisons un nouveau concept de robots continus, fortement prometteurs pour des applications biomédicales, dont la forme complexe, la dextérité et la capacité de miniaturisation constituent des avantages majeurs pour la navigation intra corporelle. Parmi cette classe, les robots à tubes concentriques (RTC), qui constituent notre point de départ, sont améliorés grâce à un actionnement embarqué innovant. Nos travaux s’articulent autour de deux thématiques aux frontières de l’état de l’art. D’une part, nous avons proposé une modélisation générique et conduit une analyse cinématique approfondie de robots continus basés sur l’architecture des RTC standards et ceux avec changement de courbure de leurs tubes dans deux variantes : courbures unidirectionnelle et bidirectionnelle. D’autre part, leur commande cartésienne en pose complète est introduite avec une validation expérimentale sur un prototype développé de RTC standard, ainsi que les simulations numériques d’une loi de commande comprenant la gestion de la redondance des RTC à changement de courbure. D’autre part, nous avons effectué la synthèse, la caractérisation et la mise en œuvre de micro-actionneurs souples basés sur les polymères électro-actifs (PEA), intégrés pour la première fois dans un robot continu.Ainsi, l’asservissement visuel d’un prototype de robot télescopique souple est proposé avec des précisions atteignant 0.21 mm sur différentes trajectoires. / Major challenges need to be risen in order to perform navigation in confined spaces with robotic systems in terms of design, modeling, and control, particularly for biomedical applications. Indeed,the complex shape, dexterity, and miniaturization ability of continuum robots can help solving intracorporeal navigation problems. Within this class, we introduce a novel concept in order to augment the concentric tube robots (CTR) with embedded actuation. Our works hinge on two majorcutting-edge thematics. On the one hand, we address modeling and kinematics analysis of standard CTR as well as variable curvature CTR with their two varieties : single and double bending directions.Furthermore, we perform the experimental validation of Cartesian control of a CTR prototype, anda task hierarchy based control law for redundancy resolution of CTR with variable curvatures. Onthe other hand, we develop the synthesis, the characterization, and the integration of soft microactuatorsbased on electro-active polymers (EAP) for the first time in a continuum robot. Thus, thevisual servoing of a telescopic soft robot is performed with precisions down to 0.21 mm following different trajectories.

Cette thèse propose un cadre méthodologique général et unifié adapté à l’étude de la locomotion d'une large gamme de robots, en particulier bio-inspirés. L'objectif de cette thèse est double. Tout d'abord, elle contribue à la classification des robots locomoteurs en adoptant les outils mathématiques mis en place par l'école américaine de mécanique géométrique. Deuxièmement,en profitant de la nature récursive de la formulation de Newton-Euler, elle propose de nouveaux outils efficaces sous la forme d'algorithmes aptes à résoudre les dynamiques externe directe et interne inverse de tout robot locomoteur approximable par un système multicorps mobile. Ces outils génériques peuvent aider l’ingénieur ou le chercheur dans la conception, la commande, la planification de mouvement des robots locomoteurs ou manipulateurs comprenant un grand nombre de degrés de liberté internes. Des algorithmes effectifs sont proposés pour les robots discrets ainsi que continus. Ces outils méthodologiques sont appliqués à de nombreux exemples illustratifs empruntés à la robotique bio-inspirée tels les robots serpents, chenilles et autres snake-board… / This thesis proposes a general and unified methodological framework suitable for studying the locomotion of a wide range of robots, especially bio-inspired. The objective of this thesis is twofold. First, it contributes to the classification of locomotion robots by adopting the mathematical tools developed by the American school of geometric mechanics.Secondly, by taking advantage of the recursive nature of the Newton-Euler formulation, it proposes numerous efficient tools in the form of computational algorithms capable of solving the external direct dynamics and the internal inverse dynamics of any locomotion robot considered as a mobile multi-body system. These generic tools can help the engineers or researchers in the design, control and motion planning of manipulators as well as locomotion robots with a large number of internal degrees of freedom. The efficient algorithms are proposed for discrete and continuous robots. These methodological tools are applied to numerous illustrative examples taken from the bio-inspired robotics such as snake-like robots, caterpillars, and others like snake-board, etc.

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