Orientador: Luiz Carlos Kretly / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-13T08:18:49Z (GMT). No. of bitstreams: 1 Atanazio_PauloFilipeBraghetto_M.pdf: 6727187 bytes, checksum: 90bbbbf904ffcce6757eeaeefe4abd96 (MD5) Previous issue date: 2009 / Resumo: O propósito deste trabalho é, a partir dos conceitos de linhas de transmissão, teoria de filtros e o conhecimento pioneiro deste grupo acerca das chaves MEMS de RF, propor duas aplicações reais baseadas nesta estrutura singular: um deslocador de fase e um filtro sintonizável na faixa de 0,1-35GHz e banda Ku (12,4-18GHz) respectivamente. Uma abordagem puramente eletromecânica é realizada na etapa inicial, observando a tensão de ativação da chave para diferentes formas estruturais, desmistificando a histerese mecânica, fenômeno intrínseco a este tipo de dispositivo. Na segunda fase do trabalho é feito um detalhamento do comportamento eletromagnético da chave MEMS, explorando fortemente a extração dos parâmetros elétricos e sua inserção em outros circuitos. Por fim, a implementação do filtro sintonizável e do deslocador de fase realizouse baseada nos conceitos de DMTL - Distributed MEMS Trasmission Lines - onde tanto a seleção da frequência central de passagem do filtro, quanto o comprimento elétrico total do deslocador são controladas pela capacitância variável da chave MEMS, de acordo com uma tensão de controle DC aplicada. / Abstract: The purpose of this work is, based on transmission line concepts, filter theory and the pioneer knowledge of this group about RF MEMS Switches, propose two physical applications employing this singular structure: a phase shifter and a tunable filter at 0.1 - 35GHz range and Ku band respectively. A purely electromechanical approach is done at the initial step, observing the switch pull-in voltages for several structural geometries, demystifying the mechanical hysteresis, intrinsic phenomena of this kind of device. On the second phase of the work, the MEMS switch electromagnetic behavior is detailed, strongly exploring the electrical parameters extraction and its application on other types of circuits. Finally, the tunable filter and phase shifter are implemented through DMTL - Distributed MEMS Transmission Lines - concepts, where frequency selection and the amount of phase shifting are controlled by the variable switch capacitance according to the applied DC control voltage. / Mestrado / Telecomunicações e Telemática / Mestre em Engenharia Elétrica

Submitted by JÚLIO HEBER SILVA (julioheber@yahoo.com.br) on 2016-12-08T17:49:42Z No. of bitstreams: 2 Dissertação - Daniel Ferreira Gonçalves - 2016.pdf: 6039771 bytes, checksum: 9dd76bacc79e08f02f565c3a309abedd (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2016-12-13T18:06:03Z (GMT) No. of bitstreams: 2 Dissertação - Daniel Ferreira Gonçalves - 2016.pdf: 6039771 bytes, checksum: 9dd76bacc79e08f02f565c3a309abedd (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-12-13T18:06:03Z (GMT). No. of bitstreams: 2 Dissertação - Daniel Ferreira Gonçalves - 2016.pdf: 6039771 bytes, checksum: 9dd76bacc79e08f02f565c3a309abedd (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-03-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Studies focused on modeling and mechanical system behavior prediction are relevant to the avoidance of excessive deflections and structural failures. Most of these systems are discretized by finite element models which are constituted by a large number of degrees of freedom, making it quite expensive computationally. In this context, the application of models reduction methods becomes particularly prominent because it provides a greater saving in time, keeping the solution quality. This work aims to study methods of reducing models applied to nonlinear dynamical systems. Among the methods aimed at reducing models, there is the Guyan method, Improved Reduction System (IRS), Iterative Improved Reduction System (IIRS) System Equivalent Reduction Expansion Process (SEREP), Component Mode Synthesis (CMS) and method of modal projection. In order to verify the efficiency of the models reduction methods when applied to nonlinear systems is presented in this paper a study where the system responses are analyzed by checking the computational cost and quality of the reduced solution of the problem for each of the mentioned methods. / Estudos voltados à modelagem e previsão do comportamento de sistemas mecânicos são relevantes na coibição de deflexões excessivas e falhas estruturais. A maioria destes sistemas são discretizados por elementos finitos cujos modelos são constituídos por elevado número de graus de liberdade tornando-se bastante oneroso computacionalmente. Neste contexto, a aplicação de métodos de redução de modelos ganha destaque especial pois proporciona maior economia de tempo, mantendo a qualidade de solução. Este trabalho tem por objetivo o estudo de métodos de redução de modelos aplicados a sistemas dinâmicos não lineares. Dentre os métodos voltados à redução de modelos, destaca-se o método de Guyan, Improved Reduction System (IRS), Iterative Improved Reduction System (IIRS), System Equivalent Reduction Expansion Process (SEREP), Component Mode Synthesis (CMS) e método da Base Modal. Com o objetivo de verificar a eficiência dos métodos de redução de modelos quando aplicados em sistemas não lineares, é apresentado neste trabalho um estudo onde são analisadas as respostas do sistema, verificando o custo computacional e a qualidade da solução do problema reduzido para cada um dos métodos citados.

O objetivo desse trabalho foi desenvolver um equipamento destinado a proporcionar a realização de exercícios terapêuticos, baseado numa abordagem sistemática de desenvolvimento de projeto orientado pelo usuário e obter um protótipo funcional. Por meio das técnicas de metodologia de projeto e dos fundamentos gerais de elementos de máquinas desenvolveram-se a fase do projeto conceitual, com interface ao projeto informacional de Souza (2016), e do projeto preliminar direcionado ao desenvolvimento de um protótipo funcional destinado à sustentação e movimentação dos membros superiores de indivíduos com disfunções motoras nos nestes membros. Devido a um conjunto de fatores provenientes dos mais diversos segmentos da sociedade, há uma demanda crescente com relação à atuação das diversas áreas da engenharia, que possam fornecer soluções tecnicamente viáveis e ainda, com um grau de personalização em massa destinadas às aplicações na área da saúde. A área de conhecimento denominada \"Tecnologia Assistiva\" (TA) inserida na área da saúde, atua principalmente no desenvolvimento de órteses, próteses e auxílio à mobilidade, desenhando fronteiras com questões de acessibilidade, com uso e adequação de produtos, bem como na atuação de áreas de habilitação e reabilitação promovendo qualidade de vida e inclusão social de indivíduos com algum tipo de deficiência ou mobilidade reduzida. Nesse trabalho, o uso de ferramentas de metodologia de projeto durante as discussões sobre o projeto informacional e a implementação do projeto conceitual, ambos de caráter interdisciplinar, permitiu estabelecer a interface entre decisões técnicas de engenharia e os requisitos do usuário. O usuário intermediário, responsável pela prescrição e avaliação do protótipo foi representado por uma amostra de terapeutas ocupacionais, que acompanharam o processo de desenvolvimento do projeto até a validação do protótipo funcional. Os resultados obtidos nesse trabalho foram: obtenção de uma lista de requisitos do usuário, que convertida em um conjunto de características técnicas permitiu o desenvolvimento do projeto orientado pelo usuário (Terapeutas Ocupacionais) e construção de um protótipo funcional. O equipamento de apoio aos exercícios terapêuticos proposto apresenta graus de inovação, quando comparado à equipamentos comerciais e patentes, principalmente: adequação à diferentes mobiliários em ambiente hospitalar e doméstico (camas, cadeiras, mesas); melhor processo de compactação do equipamento para armazenagem e transporte, feito por uma única pessoa; exercícios com os membros superiores: uni e bilateral e abertura completa dos membros superior no plano coronal por meio de guias lineares. / This work presented the development of an apparatus whose objective is allow the therapeutic exercises, based on a systematic approach user-oriented design development, and fabricate a functional prototype. Based on design methodology and machine elements theory it was developed the conceptual and the preliminary design phase, based on the informational design phase of Souza (2016), to develop a functional prototype aimed to provide support and movement of the upper limbs of people with motor dysfunction in these members. Due to a range of factors from the various segments of society, there is increasing demand related to the performance of various areas of engineering, that can provide technically feasible solutions and with a degree of mass customization intended for applications in the health area. The knowledge area of \"Assistive Technology\" (AT) is inserted in the health area and acts mainly in the development of prostheses, orthoses and aid mobility, by drawing borders with accessibility issues, using and adjusting products, in addition to acting in habilitation and rehabilitation areas, which promote quality of life and social inclusion of individuals with a disability or reduced mobility. In this work, the use of design methodology tools during the discussion on the informational design and implementation of conceptual design, both interdisciplinary, revealed the interface between technical engineering decisions and user requirements. The intermediate user, responsible for evaluating the prototype was represented by sample occupational therapists, which prescribes and follows up the use of the mechanisms and/or equipment to end users. The main result of this work was a better definition of the user requirements that allowed obtaining design parameters focusing on occupational therapists as well as the development of a functional prototype. The main technical characteristics obtained through of the interactive and iterative processes along the informational, conceptual and preliminary design phases both prototype validation were: compaction of the device (related to storage and use for one or both arms of the user). Besides, the equipment allows possibility of adaptation to different furniture and environments: hospital, clinics, small treatment rooms, domestic bed, and chairs and use; rehabilitation exercises with positions of the upper limbs: uni- and bilateral and total movement of the upper limbs on coronal plane based on linear guides.

[pt] Neste trabalho descreve-se um procedimento para o desenvolvimento de modelos reduzidos de sistemas mecânicos lineares baseado na técnica dos Grafos de Ligação. A partir da análise da estrutura topológica dos principais modelos mecânicos descritos por esta técnica estabeleceu- se uma nova formulação que possibilita a obtenção de variadas formas de representação matemática e definiu-se um grafo genérico, formado por hipercampos armazenadores e dissipadores de energia, onde se encontram as matrizes que caracterizam a dinâmica do sistema. Sobre o grafo genérico, com algumas restrições, foi aplicada uma metodologia de normalização e desacoplamento dos campos armazenadores, com base nos seus modos locais, o que permitiu a criação de um grafo particionado, acoplado através do campo dissipador. A análise dos coeficientes do campo de acoplamento leva ao grafo de Ligação Reduzido do sistema. Comprova-se a validade do procedimento através de exemplos de fácil compreensão. / [en] It is described in this work a Bond Graph based procedure to the development of linear mechanical systems reduced order models. From the analysis of the topological structure of the main mechanical models represented by this technique it was established a new formulation that permits to obtain several mathematical representation forms and it was defined a generic graph, formed by energy storage and dissipative hiperfields, where the matrices that characterizes the system dynamics are included. On the generic graph, with some constraints, it was applied a methodology for the normalization and decoupling of the energy storage fields, based on its local modes, that permits to develop a partioned graph, couplec through the dissipative field. The analysis of the coupling field coefficients permits to define the system Reduced Bond Graph. The procedure was comproved by easy comprehensive examples.

Rotational falls, or somersault falls, have led to serious and fatal injuries during the cross-country phase of Eventing competitions. Research to improve the safety of the sport began in 2000 after five fatal injuries occurred in the 1999 Eventing season. These efforts led to safety devices such as air jackets, improved helmets, and frangible/deformable fences. The focus of this thesis is to develop a more complete understanding of the horse-fence interaction as the approach motion transitions to a rotational fall. To achieve this, a large distribution of inertial properties was compiled through the development of a cylinder-based inertia approximation and a citizen science effort to gather equine geometrical measurements through a survey distributed by the United States Eventing Association (USEA). Furthermore, fundamental kinematic properties of the horse and rider were gathered from the literature. These distributions were used to conduct a Monte Carlo analysis to examine if the approach conditions of the horse and rider would result in a transition to a rotational fall upon horse-fence contact. Through the analysis the sensitivity of the main control parameters was explored to determine the dominant variables in the transition.

D'un point de vue industriel, la mise en place de nouvelles architectures de systèmes mécaniques nécessite un long processus de conception permettant de définir et d'anticiper le comportement. Dans le cas particulier des systèmes aéronautiques tels que les moteurs d'avions, un certain nombre de pièces sont particulièrement sensibles car elles doivent répondre à des impératifs stricts en termes d'encombrement, de performance et de tenue mécanique. Dans ce contexte, la prévision du comportement vibratoire revêt une importance particulière puisqu'elle permet d'évaluer le niveau des sollicitations cycliques appliquées sur le système et guide ainsi la détection en amont d'éventuels problèmes de fatigue des matériaux. La plupart du temps, des modèles numériques sont utilisés pour représenter les structures, et le comportement est simulé en résolvant un ensemble d'équations. Pour atteindre un niveau de détail répondant au besoin industriel, ces modèles peuvent être particulièrement gros, et la résolution des équations associées demande des ressources et des temps de calcul considérables. De plus, pour rendre compte au mieux des comportements observés expérimentalement, il est souvent nécessaire de prendre en compte des phénomènes non-linéaires, ce qui augmente encore la difficulté. Les travaux présentés dans ce manuscrit concernent cette problématique du comportement vibratoire des structures non-linéaires et s'orientent autour de deux axes : la réduction de modèle et le calcul des solutions multiples. L'objectif du premier axe est de contribuer à la construction de modèles numériques non linéaires réduits utilisables en conception de systèmes industriels et de proposer des outils d'exploitation et d'interprétation de ces modèles. En particulier, on considère le cas des méthodes de projection de Galerkin et on montre qu'elles sont à même de construire des modèles réduits réalistes. Des méthodes complémentaires de réduction de modèles sont également présentées dans le cas particulier de la recherche de solutions par la méthode de la balance harmonique (HBM) : on s'intéressera en particulier à des méthodes de sélection d'harmoniques. Après avoir comparé les différentes méthodes proposées sur un exemple simple de poutre non-linéaire, elles sont appliquées à un modèle de structure industrielle représentant une aube d'hélice d'open rotor. Le second axe de ces travaux concerne le calcul de solutions multiples pour les systèmes dynamiques non-linéaires. Une particularité de ces systèmes est en effet de présenter plusieurs configurations stables pour un état de sollicitation donné. Il s'agira ici de proposer des méthodes de calcul permettant de dresser la liste exhaustive des solutions possibles. Le travail présenté se concentre sur la recherche de solutions périodiques par la méthode de la balance harmonique pour des systèmes possédant des non-linéarités polynomiales. Ces restrictions conduisent à la résolution de systèmes polynomiaux pour lesquels il existe des méthodes permettant de calculer l'ensemble des solutions. En particulier, on propose l'utilisation originale de méthodes basées sur le calcul de bases de Groebner pour la résolution de systèmes polynomiaux issus de la mécanique. Les différentes méthodes présentées sont illustrées et comparées sur des exemples simples. Les résultats montrent que même pour des systèmes simples, le comportement dynamique peut être très complexe. / In an industrial context, the design of new mechanical systems requires long design processes in order to define and to anticipate the behavior of all the constitutive parts. In the particular case of aeronautical structures such as plane engines, design is especially critical since they have to meet various and strict needs (life duration, performances . . .). Then, anticipating vibratory behavior is very important as this provides information about cyclic solicitations and fatigue. Most often, numerical models are used to mimic the structure and mechanical behavior is simulated by solving a set of differential equations. In the case of industrial structures, such models can be quite large and their resolution very time-consuming. Moreover, in order to model experimental behavior realistically, it is often necessary to take nonlinear phenomena into account and thus increase the required computational effort. The work presented in this PhD deals with the study of mechanical nonlinear systems. It focuses on two principal directions : model reduction and multiple solutions computation. The goal of the first direction is to contribute to the building of numerical reduced order models usable in industrial context and to propose tools to exploit an interpret them. Particularly, Galerkin projection methods are investigated in the context of nonlinear systems reduction, showing that those methods are, under certain conditions, able to give a reliable picture of full system behavior. In the case of the harmonic balance method, complementary methods are also proposed to reduce the size of the algebraic equations system by using harmonic selection techniques. The presented methods are firstly illustrated and compared on a simple nonlinear beam example ; they are then applied to an industrial model of open rotor blade. The second direction of this work deals with the computation of multiple solutions arising in nonlinear dynamical systems. Indeed, it has been shown that such systems can present different stable configurations for a given solicitation. The objective here is to provide tools for computing such multiple solutions. We only consider the case of periodic solutions for systems with polynomial nonlinearities, treated with harmonic balance method. These hypotheses enable one to search for multiple states as solutions of polynomial algebraic systems of equations, for which some methods exist to compute the entire set of solutions. In particular, we propose to use methods relying on Groebner basis computation, in order to compute the whole set of solutions. The proposed methods are illustrated and compared on simple examples, showing that even such simple systems can present very complex dynamical behavior.

This thesis presents the design of uBot-7, the latest version of a dexterous mobile manipulator. This platform has been iteratively developed to realize a high performance-to-cost dexterous whole body manipulator with respect to mobile manipulation. The semi-anthropomorphic design of the uBot is a demonstrated and functional research platform for developing advanced autonomous perception, manipulation, and mobility tasks. The goal of this work is to improve the uBot’s ability to sense and interact with its environment in order to increase the platforms capability to operate dexterously, through the incorporation of joint torque feedback, and safely, through the implementation of passive and active compliance. This is accomplished through incorporating series elastic actuators in its arms and torso joints, improving the mechanical design to reduce backlash, and incorporating impedance controllers in the robot. The focus of this thesis is the development of the mechanical, sensor, and controller design for the uBot-7 platform. An impedance controller is developed and evaluated on a bench top prototype series elastic actuator.

The objective for this project is to investigate various electrical and software means of control to support and advance the development of a novel vacuum adhesion system for a wall-climbing robot. The design and implementation of custom electronics and a wirelessly controlled real-time software system used to define and support the functionalities of these electronics is discussed. The testing and evaluation of the overall system performance and the performance of the several different subsystems developed, while working both individually and cooperatively within the system, is also demonstrated.

This thesis presents the design, calibration, and performance evaluation of a type of two-hole pressure probe anemometer known as a Conrad probe, as well as its subsequent implementation on an autonomous, compact boundary layer measurement device and its first application for subsonic in-flight measurements of a swept wing boundary layer. Calibration of the Conrad probe was accomplished using two calibration functions and a non-nulling method for resolving in-plane flow velocity direction and magnitude over a range of ±30 degrees. This approach to calibration and application offered the advantages of rapid data acquisition with lower energy consumption than alternative methods for pressure probe anemometry in swept wing boundary layers. Following calibration, the probe was adapted for use on an autonomous boundary layer measurement device including development of revised software. Utilizing this setup, boundary layer measurements were obtained on both swept and unswept models in a wind tunnel with a maximum operational velocity of 110 mph corresponding to a dynamic pressure of 30 psf. The wind tunnel results showed that the Conrad probe could measure in-plane flow magnitude for both laminar and turbulent boundary layers with sufficient uncertainty and spatial resolution for its intended application in flight testing. The Conrad probe and boundary layer measurement system were then employed for flight tests of a 30 degree swept wing model carried beneath an aircraft at a flight Mach number of 0.52 and altitudes up to 44,000 ft. The flight test results from the Conrad probe allowed for the successful determination of overall boundary layer thickness, laminar/turbulent conditions, and degree of flow turning within the boundary layer. It is believed that the rapid data acquisition and low energy consumption of the Conrad probe implementation on the boundary layer measurement system make it a good alternative for future flight testing requiring measurements of in-plane flow velocity magnitude and direction.

The purpose of this research is to identify the configurations of several mechanism classes which result in bistable behavior. Bistable mechanisms have use in many applications, such as switches, clasps, closures, hinges, and so on. A powerful method for the design of such mechanisms would allow the realization of working designs much more easily than has been possible in the past. A method for the design of bistable mechanisms is especially needed for micro-electro-mechanical systems (MEMS) because fabrication and material constraints often prevent the use of simple, well-known bistable mechanism configurations. In addition, this knowledge allows designers to take advantage of the many benefits of compliant echanisms, especially their ability to store and release energy in their moving segments. Therefore, an analysis of a variety of mechanism classes has been performed to determine the configurations of compliant segments or rigid-body springs in a mechanism which result in bistable behavior. The analysis revealed a relationship between the placement of compliant segments and the stability characteristics of the mechanism which allows either analysis or synthesis of bistable mechanisms to be performed very easily. Using this knowledge, a method of type synthesis for bistable mechanisms has been developed which allows bistable mechanisms to be easily synthesized. Several design examples have been presented which demonstrate the method. The theory has also been applied to the design of several bistable micromechanisms. In the process of searching for usable designs for micro-bistable mechanisms, a mechanism class was defined, known as "Young" mechanisms, which represent a feasible and useful way of achieving micro-mechanism motion similar to that of any four-bar mechanism. Based on this class, several bistable micro-mechanisms were designed and fabricated. Testing demonstrated the ability of the mechanisms to snap between the two stable states. In addition, the mechanisms showed a high degree of repeatability in their stable positions.