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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Circular motion for robotized metal deposition : verification and implementation

Denys, Kristof January 2013 (has links)
Metal deposition is an additive layered manufacturing process that deposits molten metal droplets on a substrate and by repeating this process layer by layer, a complex shaped 3D geometry can be manufactured. In this thesis, the metal deposition process is performed by a robot with a wire feeder tool and a laser as energy source to melt the metal wire. The robot programming for robotized metal deposition process can be completely automated by computer aided robotics software. University West is currently developing an add-in application in a computer aided robotics software, Process Simulate, that is capable of programming the robotized metal deposition process. The first goal of this thesis was to verify the up to now developed software and the process from CAD drawing down to robot code. Another goal was to find and implement an algorithm that will reduce the number of locations on a circular arc to three locations. The algorithm to minimize the locations must be capable of changing all the different curvature paths to linear and circular arc motions which are easy to translate to robot code. The user should be able to decide the fitting precision of the approximated motion path to the original path. A real robot cell setup is modelled in Process Simulate. This lets Process Simulate generate the correct robot code for that specific cell.  Since each robot cell has its own unique setup, a custom script will be developed that changes the universal robot code, that Process Simulate generates, to the custom robot code required in this specific robot cell. The software is improved and tested from CAD drawing down to robot code but still needs to be debugged more and needs implementation of some non-existing features.
2

Návrh robotizovaného pracoviště na montáž vrtačkových sklíčidel / Design of robotized workplace for assembly of drill chucks

Koutňák, Jan January 2020 (has links)
Master's thesis is focused on design of robotized workplace for assembly of drill chucks. In the first part the fundamental issue is described. The next part contains an analysis of selected chuck, which continues with design of robotized workplace including components. The thesis is also focused on a work cycle design, risk analysis and economic evaluation. Drawing documentation, 3D workplace model and work cycle simulation video is attached.
3

Robotizované pracoviště pro opracování termoplastových dílů / Robotized workplace for treatment of thermoplastic parts

Sedláček, Tomáš January 2011 (has links)
The goal of this diploma thesis is to design a robotized workplace for treatment of thermoplastic products based on documentation from a real project announced by Form s. r. o. In order to understand a problematic of robots and robotized workplaces, the theoretic introduction in the beginning of work is reserved for. Besides a brief summary of robot history the introduction brings also some overview on present robot applications and it tries to classify robots into various groups according different standpoints. The main part of the theory however deals with optimized design of robotized workplaces by using a systematic approach. The topic covers also a robot safety. There are mentioned sources of safety risks and ways how to avoid them. The presented theory is at last used in the following, most crucial, part of the thesis – the final design itself. An attention is focused mainly to a design of a revolving positioner, which becomes a key element of whole workplace. Different design variants of inner most significant mechanisms are presented and by using sophisticated methods, the best solutions are chosen. Finally a simulation of whole robotized workplace is made and conclusions based on real implementation are summarized.
4

How can technological innovation reduce the need of financial literacy in financial planning?

Matharu, Amiteshver, Panic, Demijan January 2020 (has links)
Increasingly more people lack the basic financial knowledge that would help them plan for their future. One aspect of it is not being aware of the long-term benefit of investing in the stock market. Increasing financial literacy with better financial education is a long-term solution. In the meanwhile, there is room for technological innovation to reduce the need for financial literacy which has not been covered by previous research and is therefore the topic of this research. More specifically, this study examines how financial literacy can be reduced in financial planning for households by helping them setting up a stable financial future. A case study method was used to choose three web-based robotized products and evaluate how they scored in mitigating three identified barriers to stock market participation. The result demonstrated that choosing any of the three products significantly reduced the need of financial literacy since they all scored high. In conclusion, these types of technological products can help not only the financially illiterate but also those who want to delegate the task of planning for their financial future.
5

Commande d'un robot de télé-échographie par asservissement visuel / Control a robot tele-echography by visual servoing

Li, Tao 14 February 2013 (has links)
Les robots légers utilisés pour la télé-échographie robotisée permettent, à l'expert médical, d'orienter à distance une sonde ultrasonore 2D. L'analyse en temps réel de l'image ultrasonore du patient, reçue via un lien de communication, permet à l'expert de définir un diagnostic. Les validations cliniques du concept de télé-échographie robotisée montrent qu'il est ainsi possible de pallier le manque d'experts en ultrasonographie sur des sites médicalement isolés. Le robot porte-sonde est positionné et maintenu sur le corps du patient par un assistant à partir des informations communiquées par le spécialiste via visioconférence. Cependant, la faible masse du robot, le fait qu'il soit maintenu par un assistant sur le corps du patient et les mouvements physiologiques du patient provoquent des perturbations dans la position de la sonde et engendrent ainsi des pertes des sections d'intérêt des organes étudiés. Les travaux de cette thèse ont consisté à développer une approche par asservissement visuel basé sur les moments d'image ultrasonore 2D. Le calcul des moments 2D étant basé sur les points du contour de la section d'intérêt, un algorithme de traitement d'images efficace est nécessaire pour détecter et suivre le contour d'intérêt en mouvement. Pour cela, une méthode de contour actif paramétrique basée sur les descripteurs de Fourier est présentée. Les lois de commandes correspondant à trois tâches autonomes autorisant la recherche et le maintien de visibilité d'un organe lors de l'acte médical télé-opéré sont implémentées et validées sur la plateforme robotique du projet ANR Prosit. / The light weight robots used for robotized tele-echography allow the medical expert to remotely operate a 2D-ultrasound probe. The real-time analysis of the patient's ultrasound images, received via a standard communication link, provides the expert with relevant information to define a diagnosis. The clinical validations of the robotized tele-echography concept show that it is possible to overcome the lack of sonographers in medically isolated sites. The robot probe-holder is usually positioned and held on the patient's body by a paramedical staff based on information provided by the specialist via videoconferencing. However, the small mass of the robot, the fact that it is held by an assistant on the patient's body and the patient's physiological movements cause disturbances in the position of the probe ; this thus can generate a loss of the region of interest of the organ being under investigation during the teleoperated medical act. This thesis work focuses on the development of a visual servoing approach based on 2D ultrasound image moments. 2D moments calculation is based on the contour points of the image section of interest, therefore an image-processing algorithm is needed to effectively detect and follow the contour of interest in motion. For this reason, a parametric active contour method based on Fourier descriptors is presented. The control laws, corresponding to three independent autonomous tasks to search and maintain the visibility of an organ within a given ultrasound plane during the tele-operated medical act are implemented and validated on robotic platform project ANR Prosit.
6

Stimulation magnétique transcrânienne robotisée : de l’automatisation des protocoles à de nouvelles approches en neuroimagerie fonctionnelle / Robotized transcranial magnetic stimulation : from the automation of protocols towards new approaches in functional neuroimaging

Harquel, Sylvain 20 March 2017 (has links)
La stimulation magnétique transcrânienne (TMS) est une technique de stimulation corticale non-invasive.Depuis son apparition au milieu des années 1980, les évolutions technologiques qu’elle a connues ontconsidérablement amélioré sa fiabilité, sa précision ainsi que sa reproductibilité. Ces progrès ont favorisél’émergence d’un grand nombre d’applications, tant dans le domaine de la recherche fondamentale enneurosciences cognitives que dans celui de la recherche clinique. Cette thèse a pour objectif d’étudierles apports méthodologiques et fondamentaux de la TMS robotisée, dernière avancée technologique dudomaine. Grâce à un placement et un suivi automatisés de la bobine de stimulation, la TMS robotiséeouvre en effet la voie à l’automatisation des protocoles, ainsi qu’à l’élaboration de nouvelles approchesen neuroimagerie fonctionnelle. Les deux premières études de ce travail abordent ce premier point, enproposant le développement de deux outils nécessaires à l’automatisation du paramétrage des protocolesde TMS : CortExTool et AutoHS. CortExTool est une boîte à outils qui permet l’analyse automatisée dessignaux électromyographiques évalués durant le paramétrage, et AutoHS un modèle bayésien assurantune recherche automatique du point chaud moteur, étape essentielle de la procédure. Testée sur donnéesvirtuelles et comparée expérimentalement à la pratique manuelle d’experts sur 19 volontaires sains, laprocédure automatisée proposée ici apparaît au moins aussi fiable, tout en étant plus rapide et repro-ductible. La troisième et dernière étude de cette thèse s’attache quant à elle aux apports fondamentauxpossibles de cette technologie. Elle propose un protocole qui permet la cartographie extensive des ré-ponses électroencéphalographiques évoquées par la TMS sur 18 aires corticales réparties sur l’ensembledu néocortex. Appliquée sur 22 volontaires sains, l’analyse des propriétés dynamiques de ces réponses faitapparaître des spécificités régionales ainsi que des réseaux corticaux partageant des propriétés communes.Celles-ci étant liées aux caractéristiques cytoarchitecturales des aires stimulées, nos résultats apportent lapreuve de concept pour la cytoarchitectonie fonctionnelle, qui pourrait aboutir à une nouvelle méthodede parcellisation in vivo du cortex chez l’Homme. L’ensemble des résultats de cette thèse confirme l’intérêtde la robotisation de cette technique, qui pourrait à terme faciliter la mise en œuvre des protocoles par lescentres cliniques, et amener de nouveaux outils d’exploration fonctionnelle pour un meilleur diagnosticdes pathologies psychiatriques et neurologiques. / Transcranial Magnetic Stimulation (TMS) is a non invasive cortical stimulation tool. Major technologicalevolution has continuously increased the spatial reliability and reproducibility of TMS since its beginningin the middle of the 80’s, by minimizing the influence of human and experimental factors. Therefore, TMSestablished itself as a powerful technique for probing and treating the human brain. The aim of this thesisis to study the methodological and basics contribution of robotized TMS, as being the last technologicaladvance to date. By means of the automatic handling of the TMS coil, robotized TMS opens new avenues forthe automation of stimulation protocol, and to new approaches in functional neuroimaging. The two firststudies of this work aim at developing two tools that are still needed to achieve the automation of set-upprocedures of TMS protocols : CortExTool and AutoHS. CortExTool is a toolbox allowing the automaticanalysis of electromyographic signals, while AutoHS is a Bayesian model aiming at automatically finding themotor hotspot, which are two critical ingredients used during such procedures. We validated our automaticset-up procedure on both virtual and real data, during an experimental comparison against manual set-upprocedures on 19 healthy volunteers. Results showed that the automatic procedure was at least as reliableas the manual one, while being faster and more reproducible. The third and last study of this thesis aimed atexploring new basics approaches offered by this technology. We developed a protocol allowing the extensivemapping of evoked electroencephalographic responses on 18 cortical targets covering the whole neocortex,and tested it on 22 healthy volunteers. The analysis of the dynamical properties of these responses revealedregional specificities as well as cortical networks sharing similar properties. Our results provide the proofof concept of functional cytoarchitectonics, that would guide the parcellation of the human cortex in vivobased on its intrinsic responses to local perturbations. The results of this thesis are promising regarding thenew possibilities offered by robotized TMS. Its use could decrease the experimental variability, facilitatethe handling of TMS protocols used for research and clinical routine, and finally offer new functionalexploration approaches that could allow a better diagnosis of psychiatric and neurological pathologies.
7

Efeito da camada de nitreto na porosidade em soldas de eixos automotivos / Effect of the nitride coat on porosity in automotive axles welding

Maia, Ivan Gonçalves 29 July 2005 (has links)
Orientador: Roseana da Exaltação Trevisan / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-06T20:28:37Z (GMT). No. of bitstreams: 1 Maia_IvanGoncalves_M.pdf: 1727519 bytes, checksum: 4ae95467cd56b424526ca03c4f577c25 (MD5) Previous issue date: 2005 / Resumo: Visando solucionar o problema da ocorrência de poros em um cordão de solda de um eixo automotivo, o presente trabalho apresenta um estudo da influência de diferentes fatores na ocorrência de porosidade em juntas de aço soldadas pelo processo MIG/MAG robotizado. Basicamente, foi estudada a influência de três fatores na ocorrência dos poros. São eles, a presença de uma camada rica em nitretos na extremidade de um dos tubos que compõe a junta, a limpeza das superfícies a serem soldadas e a vazão do gás de proteção. Após a soldagem dos corpos de prova foram retiradas de cada um deles, três amostras da seção transversal do cordão de solda. A porosidade foi quantificada pela técnica de análise metalográfica por microscopia ótica. Os resultados de porosidade foram apresentados de duas maneiras, uma sem qualquer tipo de restrição quanto aos poros encontrados, e outra em que houve distinção quanto à localização dos poros na seção transversal do cordão de solda. Quando a porosidade foi quantificada de maneira geral, sem qualquer tipo de distinção quanto à localização dos poros, dois fatores influenciaram a ocorrência de poros na junta soldada. São eles, a presença da camada rica em nitretos e a vazão do gás de proteção. No outro caso, levando em consideração a localização dos poros na seção transversal do cordão de solda, foi constatado que para o caso dos poros localizados na raiz da junta, a presença da camada rica em nitretos gerada pelo processo de corte a plasma na extremidade do tubo correspondente ao metal-base 1 afetou significativamente a porosidade resultante no cordão de solda. Além dos ensaios experimentais, ensaios práticos foram realizados no próprio chão de fabrica de produção dos eixos. A realização de ensaios práticos visou avaliar a solução proposta para eliminação da ocorrência de porosidade no cordão de solda dos eixos. Os resultados destes ensaios comprovaram que a substituição do gás utilizado para o corte a plasma na extremidade do tubo correspondente ao metal-base 1, de ar comprimido por oxigênio puro, inibiu a formação dos poros / Abstract: In order to solve the occurrence of pores in weld beads of an automotive axle, the present work studies the influence of three different factors on the occurrence of porosity in joints welded by robotized GMAW process. The factors analyzed were: the presence of a region enriched by nitrides on the surface of the tube related to the base metal 1, the surface cleanliness of the joint components, and the shielding gas flow. Three samples of the weld bead transversal section were retired in each specimen. The porosity was quantified by metalographic analysis technique using an optical microscope. The results were presented by two different ways. In one of this ways, pores were quantified without any kind of distinction. In the other way, pores were grouped in accordance of their location in the weld bead transversal section. The pores quantified without any kind of distinction were affected by the ¿presence of the coat¿ and by the shielding gas flow. The pores located near the joint root were affected only by the ¿presence of the coat¿. In addition to the experimental specimens, practical experiments were made in the axles line production. These practical experiments were developed to evaluate a proposed solution to prevent the occurrence of the pores on the weld bead of the axles. The results of these practical experiments proved that changing the compressed air used in the plasma cut of the extremities of the tube related to the base metal 1 by pure oxygen gas inhibited the pores formation / Mestrado / Materiais e Processos de Fabricação / Mestre em Engenharia Mecânica
8

Modélisation de corps mous appliquée à la commande de procédé robotisé de découpe anatomique de muscles / Soft material modeling applied to the control of robotized technology of deboning and muscle separation in meat cutting

Essahbi, Nabil 13 December 2013 (has links)
Cette thèse intervient dans le cadre du projet ANR ARMS. L'objectif est de concevoir un système robotisé multi-bras pour la découpe anatomique de muscles. Ce travail vise à développer les modèles mécaniques nécessaires à la mise en place de la stratégie de commande. Il expose le cycle de développement d'un modèle mécanique faisant intervenir la construction de modèles géométriques à partir d'images IRM, l'identification expérimentale des paramètres rhéologiques des matériaux modélisés en passant par les étapes de maillage, de paramétrage, d'implémentation et de validation de tels modèles. Il présente une nouvelle méthode de modélisation dynamique de structures intitulée modèle masse-ressort non-linéaire isotrope transverse, une méthode qui témoigne d'un comportement mécanique alliant réalisme et interactivité. Il intervient aussi dans l'identification dynamique des trajectoires de coupe robotisée en proposant de nouvelles approches de modélisation de la découpe de corps mous et en développant un nouvel algorithme basé sur le calcul de courbures. Cette thèse aborde, aussi, le problème de variabilité des muscles bovins et propose une méthode de recalage dimensionnel du modèle géométrique générique par le biais de transformations géométriques définies par optimisation multicritère d'une fonction objectif. Enfin, en vue de synchroniser le flux d'informations entre les différents modules de commande de la cellule robotisée, une combinaison de la méthode des éléments finis avec la technique de condensation statique de Guyan a permis de développer un modèle mécanique quasi-statique réduit permettant de prédire rapidement l'évolution de la trajectoire de coupe robotisée. / This PhD thesis is done within the framework of the ANR ARMS project. The global objective is to study the robotization of deboning and muscle separation in meat cutting and transformation processes applied to beef rounds. This work aims to develop the necessary mechanical models feeding the process control strategy. It outlines the development cycle of a mechanical model involving the construction of geometrical models using MRI techniques, the experimental identification of rheological parameters of materials while going through the steps of meshing, parameterization, implementation and validation of such models. It presents and tests a new way to fix the parameters of the mass-spring model whilst taking into account material anisotropy. The new approach is entitled « non-linear transversally isotropic mass-sping model » and sets the model in non-linear mechanical behavior mode which therefore increases the realism of the simulations performed. It is also involved in the dynamical estimation of the cutting guideline by proposing new approaches for soft materials cutting and by developing a new algorithm based on vision perception and curvature estimation of 3D surfacic meshes. This work addresses also the problem of muscles variability and provides a readjustement method of the generic geometrical model based on a multicriteria optimization of an objective function. Finally, in order to synchronize the information flow between the control modules of the robotic cell, a combination of the finite element method with Guyan static condensation technique allowed developing a reduced quasi-static mechanical model rapidly predicting the evolution of the cutting trajectory.
9

Návrh automatického lisu / Design of automatic press

Ujčík, Miroslav January 2021 (has links)
The master's thesis deals with the design of a press, which will be part of a robotic workplace. This workplace is designed for a company operating as a subcontractor for the automotive industry, for which automation is one of the most important processes of development and increasing labor productivity. The robotized cell is part of a line for heat treatment of plastic tube semi-finished products. The cell itself is used to press the conical extension of the pipe ends using a steel mandrel. In order to manipulate the parts, the corresponding end effectors of robots are designed in the work, which safely load and remove parts from the automated press. Design and control calculations are supplemented by finite element strength analysis in Solidworks. A drawing documentation is also made in this program. The work is performed with regard to the requirements of technologists and the quality department.
10

Robotizované pracoviště pro ukládání 25 kg pytlů maltové směsi na paletu / Robotic workstation for storing 25 kg bags of mixture per pallet

Falta, Libor January 2014 (has links)
The aim of this thesis is to create the design of a robotic workstation (RWS) for storing bags on a pallets with a capacity of 600 bags per hour. As an introduction to the issues of solved task, the introductory part of the thesis deals with a general information about industrial robots, theories ofdesigning RWS and palletization. For the suggested workstation it is given to have one pickup place from the roller conveyor and two unloading places. Within the RWS it is used belt, roller and chain conveyors as a peripheral device for conveying bags and pallets. There are two variants of RWS created for the possibility of technically - economic assessment. Solution for the security and the ergonomy of the workplace are an integral part of the study. Selected components of RWS have their risk analysis carried out. There is also the draft of a robot gripper mentioned, including assembly drawing. In conclussion there is calculation of returning of funds invested in the construction of RWS. Drawings of robotized workplace disposition, schemes of pneumatic and electrical connections and block diagram of the control system of RWS are included as attachments.

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