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The purpose of this thesis is to develop an existing design of a fully controllable multi-rotor vehicle toward simulating small satellite dynamics, enabling technology development to be accelerated and component failure risks to be mitigated by providing a testing platform with dynamics similar to those of small satellites in orbit. Evaluating dynamics-sensitive software and hardware components for use in small satellite operations has typically been relegated to simulated or physically constrained testing environments. More recently, researchers have begun using multi-rotor aerial vehicles to mimic the orbital motion of such satellites, further increasing simulation fidelity. The dynamical nature of multi-rotor vehicles allows them to accurately simulate the translational dynamics of a small satellite, but they struggle to accurately simulate rotational dynamics, as conventional multi-rotor vehicles' translational and rotational dynamics are coupled. In this thesis, an optimal design for a multi-rotor vehicle independently controllable in all six degrees of freedom is evaluated as a suitable simulation platform. The design of the proposed physical system is discussed and progress toward its construction is demonstrated. To facilitate future research endeavors, a simulation of the vehicle in a software-in-the-loop environment, using the Gazebo dynamics simulator, is developed and its performance evaluated. This simulation is then used to evaluate the vehicle's feasibility as a small-satellite dynamics simulator by tasking it with tracking dynamic position and attitude time histories representative of a small satellite. / Master of Science / When developing a spacecraft, it can be difficult to accurately test software and hardware that are sensitive to the spacecraft's motion. This difficulty arises because the space environment experienced by orbiting spacecraft allows them to move and rotate freely, and recreating this freedom of motion on earth requires large, expensive, and difficult-to-access test equipment. To make this testing more accessible, researchers have begun using quadcopter drones to mimic some aspects of a spacecraft's motion. While quadcopters can move like an orbiting spacecraft can, their designs do not allow them to rotate like an orbiting spacecraft can, thus providing an incomplete recreation of spacecraft motion. To correct this shortcoming, an existing drone design that is able to move and rotate simultaneously without fear of crashing is developed, with progress shown toward its construction. A software simulation of the drone is developed to help future researchers test software and algorithms before flying it on the physical drone. The simulation is then used to see how well the drone design can recreate the motions that a small spacecraft would experience.

Submitted by Kamila Costa (kamilavasconceloscosta@gmail.com) on 2015-06-12T20:37:43Z No. of bitstreams: 1 Dissertacao-Werley M Takeda.pdf: 2678050 bytes, checksum: 44000c59a239d5b966efb9137a721331 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-06-15T18:25:20Z (GMT) No. of bitstreams: 1 Dissertacao-Werley M Takeda.pdf: 2678050 bytes, checksum: 44000c59a239d5b966efb9137a721331 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-06-15T18:26:53Z (GMT) No. of bitstreams: 1 Dissertacao-Werley M Takeda.pdf: 2678050 bytes, checksum: 44000c59a239d5b966efb9137a721331 (MD5) / Made available in DSpace on 2015-06-15T18:26:53Z (GMT). No. of bitstreams: 1 Dissertacao-Werley M Takeda.pdf: 2678050 bytes, checksum: 44000c59a239d5b966efb9137a721331 (MD5) Previous issue date: 2015-03-24 / Não Informada / The timber industry has contributed increasingly to the economy and shown itself as an important and promising economic activity. In Brazil the activity gains greater importance due to the country’s reserves of tropical forests internationally recognized as the world's largest ones. Although the region’s abundant forest assets that offer huge potential for sustained timber forestry, increased deforestation is observed. In an attempt to curb the illegal exploitation and stop deforestation, the government developed an electronic control mechanism of forest products and by-products, which served as a primary source of information in order to diagnose the forest sector in the Western Amazon, between 2007 and 2013. Important results for forest management stand up such as: 1) relevance of small farms; 2) predominance of projects in areas not subject to flooding with an incidence of at least 3 dry months; and 3) greater inclination of municipalities to deforestation profile at the expense of forest production. For clear-cutting activities, it was observed: 1) greater relevance of small farms; and 2) concentration and importance of the activity in Roraima and Acre states. As for the wood consumption, it is shown the importance of municipalities member of intermediate and old logging frontiers, and the preference for woods with characteristics very similar in density and destination of use. Finally, it is concluded that the forest management activity showed a growth of up to 2.71 times during the study period, while clearing activity decreased up to 13.31 times in the same period. Properties with up to 500 ha were more representative for both activities. Most forest management projects are located in regions with at least three dry months. The cities examined are often more inclined to deforestation, rather than timber production from forest management. Forestry activities were located near the transport infrastructure, whether natural or constructed. The assessment of similarity demonstrated the formation of clusters consisting mainly by municipalities in the same state. / O setor madeireiro tem contribuído de forma crescente com a economia do país e se mostra como uma importante e promissora atividade econômica. No Brasil a atividade ganha maior relevância devido as suas reservas de florestas tropicais internacionalmente reconhecidas como as maiores do mundo. Embora a região disponha de ativos florestais abundantes que representam um enorme potencial para a exploração florestal madeireira sustentada, observase o aumento do desmatamento. Na tentativa de coibir a exploração ilegal e conter o desmatamento, o poder público desenvolveu um mecanismo de controle eletrônico dos produtos e subprodutos florestais, o qual serviu como fonte primária de informações, a fim de diagnosticar o setor florestal na Amazônia Ocidental, entre 2007 e 2013. Como resultados importantes para manejo florestal, destacaram-se a: 1) relevância das pequenas propriedades; 2) predominância de projetos em regiões não sujeitas a inundações e com ocorrência de pelo menos 3 meses secos; e 3) maior inclinação dos municípios ao perfil de desmatamento em detrimento da produção florestal. Para a atividade de desmatamento observou-se: 1) maior relevância das pequenas propriedades; e 2) concentração e importância da atividade em Roraima e no Acre. Quanto ao consumo de madeira evidenciou-se a importância de municípios integrantes das fronteiras madeireiras intermediária e antiga, bem como a preferência por madeiras com características muito similares de densidade e destinação de uso. Por fim, conclui-se que a atividade de manejo florestal apresentou um crescimento de até 2,71 vezes, ao longo do tempo do estudo, enquanto a atividade de desmatamento decresceu até 13,31 vezes, no mesmo período. As propriedades com até 500 ha apresentaram-se mais representativas para ambas atividades. A maior parte dos projetos de manejo florestal se localiza em regiões que apresentam, pelo menos, três meses secos. Os municípios analisados apresentam-se mais inclinados ao desmatamento, em detrimento da produção madeireira manejada. As atividades florestais localizam-se próximas as infraestruturas de transportes, sejam elas naturais ou construídas. A avaliação da similaridade demonstrou a formação de agrupamentos constituídos principalmente por municípios do mesmo estado.

About 2,000 of the more than 27,000 genes of the genetic model plant Arabidopsis thaliana encode for transcription factors (TFs), proteins that bind DNA in the promoter region of their target genes and thus act as transcriptional activators and repressors. Since TFs play essential roles in nearly all biological processes, they are of great scientific and biotechnological interest. This thesis concentrated on the functional characterisation of four selected members of the Arabidopsis DOF-family, namely DOF1.2, DOF3.1, DOF3.5 and DOF5.2, which were selected because of their specific expression pattern in the root tip, a region that comprises the stem cell niche and cells for the perception of environmental stimuli. DOF1.2, DOF3.1 and DOF3.5 are previously uncharacterized members of the Arabidopsis DOF-family, while DOF5.2 has been shown to be involved in the phototrophic flowering response. However, its role in root development has not been described so far. To identify biological processes regulated by the four DOF proteins in detail, molecular and physiological characterization of transgenic plants with modified levels of DOF1.2, DOF3.1, DOF3.5 and DOF5.2 expression (constitutive and inducible over-expression, artificial microRNA) was performed. Additionally expression patterns of the TFs and their target genes were analyzed using promoter-GUS lines and publicly available microarray data. Finally putative protein-protein interaction partners and upstream regulating TFs were identified using the yeast two-hybrid and one-hybrid system. This combinatorial approach revealed distinct biological functions of DOF1.2, DOF3.1, DOF3.5 and DOF5.2 in the context of root development. DOF1.2 and DOF3.5 are specifically and exclusively expressed in the root cap, including the central root cap (columella) and the lateral root cap, organs which are essential to direct oriented root growth. It could be demonstrated that both genes work in the plant hormone auxin signaling pathway and have an impact on distal cell differentiation. Altered levels of gene expression lead to changes in auxin distribution, abnormal cell division patterns and altered root growth orientation. DOF3.1 and DOF5.2 share a specific expression pattern in the organizing centre of the root stem cell niche, called the quiescent centre. Both genes redundantly control cell differentiation in the root´s proximal meristem and unravel a novel transcriptional regulation pathway for genes enriched in the QC cells. Furthermore this work revealed a novel bipartite nuclear localisation signal being present in the protein sequence of the DOF TF family from all sequenced plant species. Summing up, this work provides an important input into our knowledge about the role of DOF TFs during root development. Future work will concentrate on revealing the exact regulatory networks of DOF1.2, DOF3.1, DOF3.5 and DOF5.2 and their possible biotechnological applications. / Mehr noch als Tiere, die ihren Lebensraum unter widrigen Umständen verlassen können, sind Pflanzen mit einem festen Standort auf ihre Anpassungsfähigkeit angewiesen. Einen entscheidenden Beitrag dazu leistet die Genregulation, d.h. das gezielte An- und Ausschalten von Erbanlagen, den Genen. Vermittelt wird dieser Regulationsprozess unter anderem durch Transkriptionsfaktoren: Proteine, die die Fähigkeit besitzen, an bestimmte Regionen der Gene zu binden und damit deren Aktivität zu beeinflussen. In der Ackerschmalwand (Arabidopsis thaliana), die als Modellpflanze in der Genetik verwendet wird, existieren etwa 2000 solcher Transkriptionsfaktoren, eingeteilt in Familien, von denen einige auch in tierischen Organismen auftreten, andere pflanzenspezifisch sind. Auf Grund ihrer Funktion als wichtige Kontrollelemente sind sie von großem wissenschaftlichem und biotechnologischem Interesse. Im Rahmen dieser Doktorarbeit sollte die Funktion von vier pflanzenspezifischen Transkriptionsfaktoren, genannt DOF1.2, DOF3.1, DOF3.5 und DOF5.2, untersucht werden, welche durch ihre spezifische Aktivität in der Wurzelspitze der Ackerschmalwand identifiziert wurden. Um die Funktion dieser vier Regulatoren aufzuklären, wurden an der Modellpflanze gentechnische Veränderungen durchgeführt und die so veränderten, auch als transgen bezeichneten Pflanzen mit molekularbiologischen und physiologischen Methoden untersucht. Es konnte gezeigt werden, dass DOF1.2 und DOF3.5 eine wesentliche Funktion beim gerichteten Wurzelwachstum spielen und ein seitliches Wachsen der Wurzel aufgrund veränderter Umwelteinflüsse verhindern, bzw. hervorrufen können. Die beiden anderen Proteine DOF3.1 und DOF5.2 erfüllen ihre Funktion in der Stammzellnische der Wurzel. Vergleichbar mit tierischen Stammzellen sind auch pflanzliche Stammzellen nicht zu einem bestimmten Zelltyp herangereift, sondern verbleiben in einem sogenannten undifferenzierten Zustand. Es konnte gezeigt werden, dass DOF3.1 und DOF5.2 zum Erhalt dieses Zustands benötigt werden, da nach Inaktivierung beider Proteine Zellspezialisierungen auftreten, die bei gentechnisch unveränderten Pflanzen nicht auftreten. Desweiteren konnte in dieser Arbeit geklärt werden, welcher Proteinabschnitt der DOF-Proteine für ihren Transport in den Zellkern notwendig ist. Denn da die pflanzlichen Erbanlagen im Zellkern vorliegen, muss für eine Einflussnahme auf deren Aktivität zunächst ein Transport der Regulationsproteine in den Zellkern stattfinden. Zusammengenommen konnte mit dieser Doktorarbeit das Wissen über Transkriptionsfaktoren und Entwicklungsprozesse der Wurzel erheblich erweitert werden. Zudem ist die Grundlage für interessante zukünftige Arbeiten gelegt worden. Dabei wird es von zentraler Bedeutung sein, komplexe Regulationsnetzwerke verstehen zu lernen und durch gezielte Manipulationen biotechnologisch nutzen zu können.

Submitted by Michele Mologni (mologni@unoeste.br) on 2017-06-23T19:31:58Z No. of bitstreams: 1 Luciana Machado Guaberto.pdf: 1335752 bytes, checksum: aa6bb850bf2257d472ca5dbfd2512a5a (MD5) / Made available in DSpace on 2017-06-23T19:31:58Z (GMT). No. of bitstreams: 1 Luciana Machado Guaberto.pdf: 1335752 bytes, checksum: aa6bb850bf2257d472ca5dbfd2512a5a (MD5) Previous issue date: 2016-12-16 / The DOF family proteins (DNA binding with One Finger) comprises unique plant transcription factors (FTs) characterized by the presence of a DNA binding domain Dof containing a similar structure to the "zinc-finger" domain. These transcription factors are involved in different roles in various biological processes in plants. Although the analysis and genomic characterization of this gene family was performed in many plant species, information on Dof genes in sweet orange (Citrus sinensis (L.) Osbeck) and their involvement in the development of the fruits is still limited. For the full identification of CsDof genes in C. sinensis, including the structures of genes, chromosomal locations, introns and phylogeny, the examination of three databases resulted in the identification of 24 genes of this FT family distributed on 7 out of 9 chromosomes of this species. Phylogenetic analysis and classification of Dof transcription factors in C. sinensis was compared with their orthologs of Arabidopsis (Arabidopsis thaliana L.) and rice (Oryza sativa L.), which allowed their classification in four major groups (A, B, C and D) and 9 subgroups (a, B1, B2, C1, C2.1, C2.2, C3, D1, D2) of DOF proteins. For gene expression analysis, the 12 Dof genes with higher abundance of transcripts in fruits based on public RNA-seq data were selected for further analysis by semi-quantitative RT-PCR. This analysis revealed the CsDof genes were differentially expressed at different stages of development (up to 90 days after anthesis). It was also possible to establish three groups regarding their transcriptional activity relative to that in leaf tissue: genes with high (up to 8X), intermediate (up to 3X) and low relative expression (below 3 X). The gene CsDof1 showed higher expression in all of the fruit development stages, indicating that this isoform plays an important role in regulating the development of the fruits of C. sinensis. Taken together, our results provide new information about the regulation of Dof genes in controlling the formation of fruits of this important fruit species. / A família de proteínas Dof (DNA binding with One Finger) compreende fatores de transcrição (FT) exclusivos de plantas, caracterizados pela presença do domínio Dof de ligação ao DNA Estes fatores de transcrição estão envolvidos em diversos processos biológicos em plantas. Embora a análise e caracterização genômica de genes desta família tenha sido realizada em muitas espécies, informações sobre genes Dof em Citrus sinensis (L.) Osbeck (laranja doce) e o seu envolvimento no desenvolvimento do fruto é limitado. Para a identificação completa dos genes CsDof em C. sinensis, incluindo as estruturas dos genes (Exons - Íntrons), localizações cromossômicas e filogenia, três bancos de dados foram analisados. Como resultado desta busca 24 genes desta família de FTs distribuídos em 7 dos 9 cromossomos desta espécie. A análise filogenética e classificação dos fatores de transcrição Dof em C. sinensis foi realizada com a inclusão dos seus ortólogos de Arabidopsis (Arabidopsis thaliana L.) e arroz (Oryza sativa L.), sendo possível estabelecer quatro grupos principais (A, B, C e D) e 9 subgrupos (A, B1, B2, C1, C2.1, C2.2, C3, D1 e D2) de proteínas Dof. Foram selecionados 12 genes putativamente mais expressos em frutos de acordo com dados públicos de RNA-seq para a análise da expressão gênica por RT-PCR. Estes genes foram diferencialmente expressos durante as fases iniciais do desenvolvimento do fruto, sendo possível estabelecer três grupos: genes com alta expressão (acima de 8 X), expressão intermediária (acima de 3 X) e baixa expressão relativa (abaixo de 3 X) em relação à atividade transcricional em folhas. O gene CsDof1 se destacou como o gene com a maior expressão, sendo que esta manteve-se elevada em todos os estádios de desenvolvimento do fruto, evidenciando que esta isoforma desempenha um importante papel na regulação do desenvolvimento de frutos de C. sinensis. Considerados em conjunto, os nossos resultados fornecem novas informações sobre os genes CsDof na complexa rede regulatória envolvida no desenvolvimento dos frutos de laranja doce.

Physical and cognitive disabilities make it difficult or impossible to perform simple personal or job-related tasks. The primary objective of this research and development effort is to assist persons with physical disabilities to perform activities of daily living (ADL) using a smart 9-degrees-of-freedom (DOF) modular wheelchair-mounted robotic arm system (WMRA). The combination of the wheelchair's 2-DoF mobility control and the robotic arm's 7-DoF manipulation control in a single control mechanism allows people with disabilities to do many activities of daily living (ADL) tasks that are otherwise hard or impossible to accomplish. Different optimization methods for redundancy resolution are explored and modified to fit the new system with combined mobility and manipulation control and to accomplish singularity and obstacle avoidance as well as other optimization criteria to be implemented on the new system. The resulting control algorithm of the system is tested in simulation using C++ and Matlab codes to resolve any issues that might occur during the testing on the physical system. Implementation of the combined control is done on the newly designed robotic arm mounted on a modified power wheelchair and with a custom designed gripper. The user interface is designed to be modular to accommodate any user preference, including a haptic device with force sensing capability, a spaceball, a joystick, a keypad, a touch screen, head/foot switches, sip and puff devices, and the BCI 2000 that reads the electromagnetic pulses coming out of certain areas of the brain and converting them to control signals after conditioning. Different sensors (such as a camera, proximity sensors, a laser range finder, a force/torque sensor) can be mounted on the WMRA system for feedback and intelligent control. The user should be able to control the WMRA system autonomously or using teleoperation. Wireless Bluetooth technology is used for remote teleoperation in case the user is not on the wheelchair. Pre-set activities of daily living tasks are programmed for easy and semi-autonomous execution.

One of the main advantages of the Gantry-Tau machine is a large accessible workspace\footprint ratio compared to many other parallel machines. The Gantry-Tau improves this ratio further by allowing a change of assembly mode without internal link collisions or collisions between the links and the moving TCP platform. In this Thesis some of the features of the Gantry-Tau structure are described and results are presented from the analysis of the kinematic, elastostatic and elastodynamic properties of the PKM. However, the optimal kinematic, elastostatic and elastodynamic design parameters of the machine are still difficult to calculate and this thesis introduces a multi-objective optimisation scheme based on the geometric approach for the workspace area, unreachable area, joint angle limitations and link collisions as well as the functional dependencies of the elements of the static matrix and the Laplace transform to define the first resonance frequency and Cartesian and torsional stiffness. The method to calculate the first resonance frequency assumes that each link and universal joint can be described by a mass-springdamper model and calculates the transfer function from a Cartesian (TCP) force or torque to Cartesian position or orientation. The geometric methods involve the simple geometric shapes (spheres, circles, segments, etc) and vectors. The functional dependencies are based on the properties between the kinematic parameters. These approaches are significantly faster than analytical methods based on the inverse kinematics or the general Finite Elements Method (FEM). The reconfigurable Gantry-Tau kinematic design obtained by multi-objective optimisation gives the following features: • Workspace/footprint ratio more than 3.19. • First resonance frequency greater than 48 Hz. • Lowest Cartesian stiffness in the workspace 5N/μm. • The unreachable space in the middle of the workspace is not detected. • No link collisions. The results show that by careful design of the PKM, a collision free workspace without the unreachable area in the middle can be achieved. High stiffness and high first resonance frequency are important parameters for the the Gantry-Tau when used in industrial applications, such as cutting, milling and drilling of steel or aluminium and pick-and-place operations. These applications require high static and dynamic accuracy in combination with high speed and acceleration. The optimisation parameters are the support frame lengths, actuator positions,endeffector kinematics and the robot’s arm lengths. Because of the fast computational speed of the geometric approaches and computational time saving of the methods based on the functional dependency, they are ideal for inclusion in a design optimisation framework, normally a nonlinear optimisation routine. In this Thesis the evolutionary algorithm based on the complex search method is used to optimise the 3-DOF Gantry-Tau. The existing lab prototype of this machine was assembled and completed at the University of Agder

<p>This thesis studies path generation for industrial robots of six degrees of freedom. A path is defined by connection of simple geometrical objects like arcs and straight lines. About each point at which the objects connect, a region, henceforth called a zone, is defined in which deviation from the defined path is permitted. The zone allows the robot to follow the path at a constant speed, but the acceleration needed may vary. </p><p>Some means of calculating the zone path as to make the acceleration continuous will be presented. In joint space the path is described by the use of cubic splines. The transformation of the Cartesian path to paths in joint space will be examined. Discontinuities in the second order derivatives will appear between the splines. </p><p>A few examples of different zone path calculations will be presented where the resulting spline functions are compared with respect to their first and second order derivatives. An investigation of the number of spline functions needed when, given an upper limit of deviation, the transformation back to Cartesian coordinates is made.</p>

In this thesis, a strategy to accomplish pick-and-place operations using a six degree-of-freedom (DOF) robotic arm attached to a wheeled mobile robot is presented. This research work is part of a bigger project in developing a robotic-assisted nursing to be used in medical settings. The significance of this project relies on the increasing demand for elderly and disabled skilled care assistance which nowadays has become insufficient. Strong efforts have been made to incorporate technology to fulfill these needs. Several methods were implemented to make a 6-DOF manipulator capable of performing pick-and-place operations. Some of these methods were used to achieve specific tasks such as: solving the inverse kinematics problem, or planning a collision-free path. Other methods, such as forward kinematics description, workspace evaluation, and dexterity analysis, were used to describe the manipulator and its capabilities. The manipulator was accurately described by obtaining the link transformation matrices from each joint using the Denavit-Hartenberg (DH) notations. An Iterative Inverse Kinematics method (IIK) was used to find multiple configurations for the manipulator along a given path. The IIK method was based on the specific geometric characteristic of the manipulator, in which several joints share a common plane. To find admissible solutions along the path, the workspace of the manipulator was considered. Algebraic formulations to obtain the specific workspace of the 6-DOF manipulator on the Cartesian coordinate space were derived from the singular configurations of the manipulator. Local dexterity analysis was also required to identify possible orientations of the end-effector for specific Cartesian coordinate positions. The closed-form expressions for the range of such orientations were derived by adapting an existing dexterity method. Two methods were implemented to plan the free-collision path needed to move an object from one place to another without colliding with an obstacle. Via-points were added to avoid the robot mobile platform and the zones in which the manipulator presented motion difficulties. Finally, the segments located between initial, final, and via-points positions, were connected using straight lines forming a global path. To form the collision-free path, the straight-line were modified to avoid the obstacles that intersected the path. The effectiveness of the proposed analysis was verified by comparing simulation and experimental results. Three predefined paths were used to evaluate the IIK method. Ten different scenarios with different number and pattern of obstacles were used to verify the efficiency of the entire path planning algorithm. Overall results confirmed the efficiency of the implemented methods for performing pick-and-place operations with a 6-DOF manipulator.

This thesis studies path generation for industrial robots of six degrees of freedom. A path is defined by connection of simple geometrical objects like arcs and straight lines. About each point at which the objects connect, a region, henceforth called a zone, is defined in which deviation from the defined path is permitted. The zone allows the robot to follow the path at a constant speed, but the acceleration needed may vary. Some means of calculating the zone path as to make the acceleration continuous will be presented. In joint space the path is described by the use of cubic splines. The transformation of the Cartesian path to paths in joint space will be examined. Discontinuities in the second order derivatives will appear between the splines. A few examples of different zone path calculations will be presented where the resulting spline functions are compared with respect to their first and second order derivatives. An investigation of the number of spline functions needed when, given an upper limit of deviation, the transformation back to Cartesian coordinates is made.