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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.
41

Concurrent Design of Reconfigurable Robots using a Robotic Hardware-in-the-loop Simulation

Chhabra, Robin 24 February 2009 (has links)
This thesis discusses a practical approach to the concurrent analysis and synthesis of reconfigurable robot manipulators based on the alternative design methodology of Linguistic Mechatronics (LM) as well as the utilization of a modular Robotic Hardware-In-the-Loop Simulation (RHILS) platform. Linguistic Mechatronics is a systematic design methodology for mechatronic systems, which formalizes subjective notions and simplifies the optimization process, in the hope that numerous naturally different design variables can be considered concurrently. The methodology redefines the ultimate goal of design based on the qualitative notions of wish and must satisfactions. The underlying concepts of LM are investigated through a simulation case study. In addition, the RHILS platform involving physical joint modules and a control unit, which takes into account various physical phenomena and reduces the simulation complexities, is employed to the design architecture. Ultimately, the new approach is applied to redesigning kinematic, dynamic and control parameters of an industrial manipulator.
42

Tagungsband Mechatronik 2011

02 May 2011 (has links) (PDF)
Mit dieser sechsten Auflage der Tagung MECHATRONIK 2011 verbindet sich neben dem 10-jährigen Tagungsjubiläum (die erste Tagung fand im Jahre 2001 statt) auch gleichzeitig eine Premiere. Nachdem die ersten fünf Tagungen erfolgreich unter den Fittichen des VDI bzw. des VDI-Wissensforums stattgefunden hatten, beginnt das zweite MECHATRONIK-Dezennium in einem geänderten Format und mit neuen Verantwortlichkeiten und wird dennoch die bewährten Traditionen der deutschsprachigen Mechatronik-Fachgemeinde weiter pflegen. Academia trifft Industrie — Mechatronik und mechatronische Produkte sind seit jeher geprägt durch die Verknüpfung von interdisziplinärem methodenorientierten Wissen und nutzerorientierter Produktgestaltung. Diese Verknüpfung bildet sich höchst erfolgreich speziell in der deutschsprachigen Mechatronik-Fachgemeinde ab, nicht zuletzt deshalb haben deutsche Mechatronikprodukte weltweit eine exzellente Marktpräsenz. Diese enge Verzahnung ist aber ebenso im Tagungsgeschehen etabliert, wo seit vielen Jahren, im Gegensatz zu vielen anderen Ländern und internationalen Tagungen, eine gute Balance zwischen Teilnehmern aus Hochschulen und Industrie gegeben ist. Dies trifft auch auf die MECHATRONIK 2011 zu, mit 47 (70 %) Beiträgen aus Hochschulen und 20 (30 %) Beiträgen aus der Industrie bzw. Industriebeteiligung. Academia trifft Industrie — Dieser Sachverhalt wird zukünftig auch ganz transparent an den Tagungsorten und dem Tagungsumfeld sichtbar sein. Ab diesem Jahr 2011 wird die Organisation und Ausrichtung durch akademische Tagungsveranstalter durchgeführt werden. Die bisherigen wissenschaftlichen Tagungsleiter Prof. Burkhard Corves (Rheinisch- Westfälische Technische Hochschule - RWTH Aachen) und Prof. Klaus Janschek (Technische Universität Dresden) werden zukünftig gemeinsam mit Prof. Torsten Bertram (Technische Universität Dortmund) für die Ausrichtung und Durchführung verantwortlich zeichnen. Als Veranstaltungsort sind entsprechende Räumlichkeiten an den beteiligten Universitäten geplant (2011 in Dresden, 2013 in Aachen, 2015 in Dortmund). Neben einer Kostenersparnis erwarten sich die Veranstalter durch das gegenüber Kongresszentren doch intimere Umfeld einen lebendigen Gedankenaustausch zwischen Wissenschaftlern, Industrievertretern und nicht zuletzt mit dem wissenschaftlichen Nachwuchs. Speziell Studierenden soll damit ein einfacherer Zugang in die Welt des wissenschaftlichen Diskurses mit Experten aus der Industrie und Praxis ermöglicht werden. Academia trifft Industrie — Eine Stärke der bisherigen MECHATRONIK-Tagungen war immer die breite fachliche Verankerung durch die verantwortliche Trägerschaft der VDI-Gesellschaft Produkt- und Prozessgestaltung (VDI-GPP) und VDI/VDE-Gesellschaft Mess- und Automatisierungstechnik (VDI/VDEGMA). Im Selbstverständnis dieser Fachgesellschaften spielt die Bereitstellung von Kommunikationsplattformen zwischen Hochschulen und Industrie eine zentrale Rolle. In den verschiedenen Fachausschüssen von VDI-GPP und VDI/VDE-GMA findet dieser Meinungs- und Informationsaustausch regelmäßig statt. Um eine breitere Fachöffentlichkeit in diese Diskussionen einzubeziehen, ist eine gemeinsame Tagung zum Thema Mechatronik eine logische und fruchtbare Konsequenz. Auch zukünftig wird der enge fachliche und institutionelle Kontakt der Tagung MECAHTRONIK zu den Fachgesellschaften aufgrund der personellen Verankerung der Tagungsveranstalter in den Fachgesellschaften VDI-GPP und VDI/VDE-GMA erhalten bleiben. Das Tagungsprogramm 2011 bietet ein breit gefächertes Angebot an aktuellen und innovativen Fragestellungen zur Mechatronik: mechatronische Produkte, Serienfertigung mechatronischer Produkte, Ressourceneffizienz, Nutzerfreundlichkeit und Akzeptanz, Entwicklungsmethoden und -werkzeuge sowie innovative Konzepte.
43

Control of Vibratory Energy Harvesters in the Presence of Nonlinearities and Power-Flow Constraints

Cassidy, Ian Lerner January 2012 (has links)
<p>Over the past decade, a significant amount of research activity has been devoted to developing electromechanical systems that can convert ambient mechanical vibrations into usable electric power. Such systems, referred to as vibratory energy harvesters, have a number of useful of applications, ranging in scale from self-powered wireless sensors for structural health monitoring in bridges and buildings to energy harvesting from ocean waves. One of the most challenging aspects of this technology concerns the efficient extraction and transmission of power from transducer to storage. Maximizing the rate of power extraction from vibratory energy harvesters is further complicated by the stochastic nature of the disturbance. The primary purpose of this dissertation is to develop feedback control algorithms which optimize the average power generated from stochastically-excited vibratory energy harvesters. </p><p>This dissertation will illustrate the performance of various controllers using two vibratory energy harvesting systems: an electromagnetic transducer embedded within a flexible structure, and a piezoelectric bimorph cantilever beam. Compared with piezoelectric systems, large-scale electromagnetic systems have received much less attention in the literature despite their ability to generate power at the watt--kilowatt scale. Motivated by this observation, the first part of this dissertation focuses on developing an experimentally validated predictive model of an actively controlled electromagnetic transducer. Following this experimental analysis, linear-quadratic-Gaussian control theory is used to compute unconstrained state feedback controllers for two ideal vibratory energy harvesting systems. This theory is then augmented to account for competing objectives, nonlinearities in the harvester dynamics, and non-quadratic transmission loss models in the electronics.</p><p>In many vibratory energy harvesting applications, employing a bi-directional power electronic drive to actively control the harvester is infeasible due to the high levels of parasitic power required to operate the drive. For the case where a single-directional drive is used, a constraint on the directionality of power-flow is imposed on the system, which necessitates the use of nonlinear feedback. As such, a sub-optimal controller for power-flow-constrained vibratory energy harvesters is presented, which is analytically guaranteed to outperform the optimal static admittance controller. Finally, the last section of this dissertation explores a numerical approach to compute optimal discretized control manifolds for systems with power-flow constraints. Unlike the sub-optimal nonlinear controller, the numerical controller satisfies the necessary conditions for optimality by solving the stochastic Hamilton-Jacobi equation.</p> / Dissertation
44

Control of nonlinear mechatronic systems control and modeling of nonlinear systems with applications in robotics

Tatlicioglu, Enver January 1900 (has links)
Zugl.: Clemson, Clemson Univ., Diss., 2007 / Hergestellt on demand
45

MCAD - ECAD integration : constraint modeling and propagation /

Chen, Kenway. January 2008 (has links)
Thesis (M. S.)--Mechanical Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Schaefer, Dirk; Committee Member: Panchal, Jitesh; Committee Member: Paredis, Chris; Committee Member: Rosen, David; Committee Member: Yoder, Douglas. Part of the SMARTech Electronic Thesis and Dissertation Collection.
46

Computer control of a metal bar bending press

Van der Merwe, Dirk (Dirk Jacobus) 12 1900 (has links)
Thesis (MEng)--University of Stellenbosch, 2000. / ENGLISH ABSTRACT: Mechatronics is an exciting research area that stemmed from huge progress in computer technology from the 1970s onwards. In such systems, computer controlled electronic and mechanical devices interact so intimately that it is impossible to tell where the one ends and the other begins. A mechatronic project aimed at automated manufacturing was undertaken by the Department of Industrial Engineering at the University of Stellenbosch as part of their programme in mechatronics. ROYIC was the industrial partner in the joint venture. ROYIC manufactures a front loader that is used on tractors. The front loader fits on a tractor by means of a kit that has to be manufactured specially for each type of tractor. The design of the kit needed many welding joints, which lead to a difficult and expensive manufacturing process. A bending press that was capable of bending pre-cut steel into a predefined shape was identified as a viable solution. The mechanical design for the project was done by ROYIC, while the University was responsible for the electronic control. Bending is carried out by pushing a flat bar over a Y-block into the bending position which can be read from a position encoder. The bending blade then bends the metal until the appropriate angle is reached. It is impossible to predict the resulting angle by means of analytical techniques. This is due to non-linear behaviour caused by spring-back. The position of the bending blade is read with an incremental encoder. An empirical equation is used to convert the distance read by the sensor into the appropriate angle. The parameters are deduced by means of non-linear regression methods. A mean square error of 0.069 was obtained for the equation when operating in the linear area of the plastic region of bending. A software application was written to enable ROYIC to deduce the needed parameters of the equation for all types of steel. Pulse control was used to control the bending blade. The blade moves continuously until a pulse band is reached. The blade is pulsed from there into a dead band. Consequently the accuracy of the machine is determined by the width of the dead band. The control program is capable of executing bend sequence files to enable the operator to perform a sequence of bends on a metal bar. Safety was of great importance in the design. The control system was designed to give priority to safety signals over other control signals. Dangerous situations owing to computer failure are thus prevented. / AFRIKAANSE OPSOMMING: Megatronika is 'n opwindende navorsingsarea wat ontstaan het uit groot vooruitgang in rekenaartegnologie vanaf 1970. In megatroniese sisteme werk rekenaar beheerde elektroniese en meganiese toestelle so nou saam dat dit onmoontlik is om agter te kom waar die een begin en die ander eindig. 'n Megatronika projek gerig op vervaardigings outomatisasie is onlangs onderneem deur die Departement van Bedryfsingenieurswese van die Universiteit van Stellenbosch as deel van hul program in megatronika. ROVle was die industriële vennoot in die projek. ROVle vervaardig implemente vir gebruik op plase. Een van hul produkte is 'n laaigraaf wat met 'n hegstuk op 'n trekker pas. Die hegstuk moet spesifiek vir elke tipe trekker ontwerp word wat gelei het tot 'n ontwerp met baie sweislaste wat 'n tydrowende vervaardigingsproses vereis. 'n Staal buigmasjien wat vooraf gesnyde staal in 'n spesifieke vorm kan buig sou hierdie probleem kon oorbrug. Die meganiese ontwerp vir die masjien is gedoen deur ROVle terwyl die Universiteit verantwoordelik was vir die elektroniese beheer. Staal word gebruik deur 'n staalbalk te skuif oor die buigbed tot in die buigposisie wat afgelees word vanaf' n posisie enkodeerder. Die buiglem buig dan die staal in die benodigde hoek. Geen analitiese metodes bestaan om die buighoek te voorspel nie weens terugspringing. Die posisie van die buiglem word ingelees met behulp van 'n inkrementeie enkodeerder. 'n Empiriese vergelyking word gebruik om die afstand beweeg om te skakel in 'n buighoek. Die verskillende parameters word afgelei deur middel van regressie metodes. Die gemiddelde foute kwadraat was 0.069 wat getoets is vir slegs die lineêre area van die plastiese gebied. 'n Program is geskryf wat ROVle instaat stelom die benodigde parameters self af te lei. Puls beheer is gebruik op die beheer van die buiglem. Die lem beweeg kontinu tot binne die puls band en word daarvandaan gepuls tot by die stopband. Die grootte van die stopband bepaal dus die akkuraatheid van die masjien. Die beheerprogram kan ook buig sekwensie lêers uitvoer wat die operateur instaat stelom 'n reeks van buigings op 'n staal balk uit te voer. Veiligheid het deurgaans 'n belangrike rol gespeel in die ontwerp van die masjien. Die stelsel is ontwerp om prioriteit te gee aan veiligheidseine bo enige ander beheersein. Gevaarlike situasies wat mag ontstaan as die rekenaar sou faal, word dus voorkom.
47

Research and development of an intelligent AGV-based material handling system for industrial applications

Ferreira, Tremaine Pierre January 2015 (has links)
The use of autonomous robots in industrial applications is growing in popularity and possesses the following advantages: cost effectiveness, job efficiency and safety aspects. Despite the advantages, the major drawback to using autonomous robots is the cost involved to acquire such robots. It is the aim of GMSA to develop a low cost AGV capable of performing material handling in an industrial environment. Collective autonomous robots are often used to perform tasks, that is, more than one working together to achieve a common goal. The intelligent controller, responsible for establishing coordination between the individual robots, plays a key role in managing the tasks of each robot to achieve the common goal. This dissertation addresses the development of an AGV capable of such functionality. Key research areas include: the development of an autonomous coupling system, integration of key safety devices and the development of an intelligent control strategy that can be used to govern the operation of multiple AGVs in an area.
48

Estudo dinâmico e simulação de uma plataforma de Stewart com ênfase na implementação do sistema de controle / Dynamic study and simulation of the Stewart platform with emphasis on control system

Moretti, Mariana 06 January 2010 (has links)
Orientador: João Maurício Rosário / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-16T10:12:15Z (GMT). No. of bitstreams: 1 Moretti_Mariana_M.pdf: 12180551 bytes, checksum: 7061efe63e86e5ba1b21c21253c1ee35 (MD5) Previous issue date: 2010 / Resumo: Uma nova proposta de modelo dinâmico da Plataforma de Stewart é apresentada neste trabalho. Enquanto a cinemática inversa é usada para posicionar cada um dos seis braços do robô, o vetor de força que atua em seus deslocamentos é dado pelo torque de motores elétricos. A inércia em cada um dos pontos de apoio é aproximada por uma rigidez mecânica associada ao modulo de Young. Ainda, foi implementado um modelo dinâmico que usa a aproximação de Newton-Euler, amplamente aplicada na dinâmica inversa de robôs seriais, para o caso deste robô paralelo. Em ambas as abordagens, as equações foram implementadas em Matlab/SimulinkTM, e os resultados das simulações foram apresentados para validação das aproximações / Abstract: A new proposal for a dynamic model of the Stewart platform is presented. While the inverse kinematics is used to position each of the six arms of the robot, the vector of force acting on the displacement is given by the torque of electric motors. The inertia in each of the support points is approximated by a mechanical stiffness associated with the Young modulus. Still, it was implemented a dynamic model that uses the Newton-Euler approach, widely applied in the inverse dynamics of serial robots, for the case of this parallel robot. In both approaches, the equations were implemented in Matlab/SimulinkTM, and the simulation results were presented for validation of the approaches / Mestrado / Mecanica dos Sólidos e Projeto Mecanico / Mestre em Engenharia Mecânica
49

Sobre técnicas para manutenção e diagnóstico inteligente de sistemas mecatrônicos = estudo de caso utilizando cálculo de ordem fracionária / About intelligent maintenance and diagnosis techniques for mechatronic systems : case study using fractional order calculus

Gutiérrez Carvajal, Ricardo Enrique 19 August 2018 (has links)
Orientadores: João Maurício Rosário, José António Tenreiro Machado / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-19T05:49:27Z (GMT). No. of bitstreams: 1 GutierrezCarvajal_RicardoEnrique_D.pdf: 5678038 bytes, checksum: 2d6613e04b5a55fb2cf01fb83210ee32 (MD5) Previous issue date: 2011 / Resumo: A competitividade no mercado global exige cada vez mais a fabricação de produtos de alta qualidade em curto tempo de fabricação, evitando tempos de parada para manutenção e reparo de máquinas e equipamentos, exigindo assim um eficiente controle de qualidade do processo e dos produtos para evitar a ocorrência de falhas de fabricação e utilização. A integração de novas tecnologias em produtos industriais (ex. tecnologias mecatrônicas) exige a utilização de técnicas avançadas para o diagnóstico de falhas, a partir de análise dos sinais obtidos a partir do sensoriamento dos equipamentos, minimizando assim os custos de utilização de mão de obra especializada para controle de qualidade do produto. Neste trabalho é apresentado inicialmente, um estudo sobre o estado da arte em técnicas de manutenção industrial, com ênfase nas estratégias utilizadas para manutenção corretiva, periódica e baseada no comportamento com ênfase no estudo das técnicas de processamento do sinal e identificação de sistemas, frequentemente utilizadas no diagnóstico de sistemas mecatrônicos, que exigem uma grande quantidade de informações, e forte dependência da análise criteriosa de um técnico especializado. Assim, neste trabalho são utilizados sistemas de ordem fracionária, que permite a aproximação do comportamento real do sistema por meio de modelos com menos coeficientes que o sistema real, simplificando a análise do sistema em estudo. Um estudo experimental de caso para validação do trabalho é realizado a partir de uma bancada experimental de um sistema de transmissão por engrenagens que permitiu introduzir falhas particulares no sistema e sua identificação / Abstract: The global market competitiveness requires to make high quality products in a short time of manufacturing, avoiding stop-times due to maintenance and repairing of machines and devices, therefore, demanding an efficient quality control of the manufacturing process, in order to shun failures in fabrication and utilization. The integration of new technologies into industrial products (e.g. mechatronics technologies) requires the use of advanced techniques to a precise failure diagnosis. They are typically based on signal analyses, which are obtained from the machines' instrumentation, and consequently, reduce the manpower costs associated to quality control of particular products. In this work it is introduced a literature review of industrial maintenance techniques, focusing in the strategies used into corrective, periodic and condition based maintenance, specially using signal processing and system identification. Those paradigms are frequently applied into the mechatronics systems diagnosis, but requires a huge amount of information and it is strongly dependent on the specialist criterion. In this sense, we introduced a fractional order system approach, which results in a better approximation of the actual system through an few parameters architecture, hence simplifying the analysis of the actual system. A real experimental setup was used to validate the strategies studied in this work. It consist in a gear transmission that lets to introduce particular failures for a posterior identification / Doutorado / Mecanica dos Sólidos e Projeto Mecanico / Doutor em Engenharia Mecânica
50

Simulations and feedback control of nonlinear coupled electromechanical oscillators for energy conversion applications

Unknown Date (has links)
This thesis discusses the coupling of a mechanical and electrical oscillator, an arrangement that is often encountered in mechatronics actuators and sensors. The dynamics of this coupled system is mathematically modeled and a low pass equivalent model is presented. Numerical simulations are then performed, for various input signals to characterize the nonlinear relationship between the electrical current and the displacement of the mass. Lastly a framework is proposed to estimate the mass position without the use of a position sensor, enabling the sensorless control of the coupled system and additionally providing the ability for the system to act as an actuator or a sensor. This is of value for health monitoring, diagnostics and prognostics, actuation and power transfer of a number of interconnected machines that have more than one electrical system, driving corresponding mechanical subsystems while being driven by the same voltage source and at the same time being spectrally separated and independent. / by Dimitrios Psarrou. / Thesis (M.S.C.S.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.

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