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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.
71

Shaft Transducerless Vector Control Of The Interior Permanent Magnet Motor With Speed And Position Estimation Using High Frequency Signal Injection And Flux Observer Methods

Goksu, Omer 01 May 2008 (has links) (PDF)
In this thesis, shaft transducerless vector control of Interior Permanent Magnet (IPM) motor with speed and position estimation using saliency based high frequency signal injection and fundamental model based flux observer methods will be investigated. The magnetic saliency characteristic of a 2.2-kW IPM motor will be experimentally extracted by means of high frequency signal injection. High frequency signal injection method will be used to estimate the speed and position at zero and low speed based on the magnetic saliency of the IPM motor. At high speed, fundamental model based flux observer method will be utilized for speed and position estimation. Seamless transition between the two estimation methods will be provided. Using the estimated speed and position information, the motor will be closed loop vector controlled and the drive motion performance over wide speed and load range will be investigated. The IPM motor drive and the estimation/control algorithms will be modeled and their performance will be demonstrated by detailed computer simulations. A three-phase voltage source inverter and a motor test bench will be built, and the estimation/control algorithms will be implemented on a DSP based motor control platform. The IPM motor drive system will be tested in the laboratory and the theory and simulation results will be verified by the experiments.
72

Design, Modeling And Control Of Shape Memory Alloy Based Poly Phase Motor

Sharma, S Venkateswara 01 November 2008 (has links)
In this thesis, a new Poly Phase Motor (rotary actuator) based on the Shape Memory Alloy (SMA) is presented. Details of Design, Modeling, Characterization, Realization and Control of Poly Phase SMA Motor are presented. Motor with 3 and 6 Phases, with appropriate Control circuit have been realized in laboratory and simulated results have been verified experimentally. In literature, broadly two types of Shape Memory Alloy based motors namely limited rotation motor and unlimited rotation motor are found. In the unlimited rotation type SMA based motor the SMA element is in the spring form. Hence, an attempt has been made in this research to develop an Unlimited Rotating type Balanced Poly Phase Motor based on SMA wire in series with a spring in each phase. By isolating SMA actuation and spring action a constant force by the SMA wire through out its range of operation is achieved. While designing the motor, similarity in function between Poly Phase SMA Motor and Stepper Motor was found. Hence, the Poly Phase Motor is characterized similar to that of a Stepper Motor. Functionally, the Poly Phase Motor can be used in stepping mode for generating incremental motion and servo mode for generating continuous motion. Various parameters of the motor have been defined. The motor can be actuated in either direction with different Phase sequencing methods, which are presented in this work. While explaining sequencing methods, effect of the thermal time constants has also been presented. The lumped thermal model is used for dynamic simulation of motor. The motor has been modeled with a new approach to the SMA wire Hysteresis model. This model is simple and useful for real time control applications. Model is implemented using Simulink and used for the simulation of the motor. Generalization of the motor concept is done and motor up to 16 Phases are studied and the simulation results done using MATLAB are discussed. It could be observed that the torque generated by the motor increases with increased number of phases while the torque ripple reduces. The motor torque ripple is better for motor with odd number of phases due to its construction. Two methods of achieving servo motion are presented. The first method is Micro Stepping, consisting of controlling single phase temperature with a position feedback. The second method is Antagonistic Control of temperatures of phases with position feedback. Both the above methods use PID Controller with optical encoder feedback for position sensing. Performance of the actuator with step, ramp and triangle inputs has been simulated using Simulink and verified experimentally for various loads and disturbances. Positional accuracy of 0.07% for the Step input and for the full rotation of 3600 is achieved. Vector Control of SMA Motor is presented. By this method Speed and the torque of the motor will be effectively controlled. Since the temperatures of the wires are controlled in this research, this method is named as Thermal Space Phasor or Vector Based Control. This method of rotation of motor is simulated using Simulink and verified experimentally. Here the current through the SMA is controlled so as to get near sinusoidal variation in temperature. This leads to a near Sinusoidal variation of force. It is shown that by controlling the temperature of phases Sinusoidally with a phase shift of 1200, the Resultant Force will be a constant over the Spatial angle of 3600 and its Velocity of rotation will be Constant. Open loop and closed loop control of the speed and torque is presented. While the motor rotates at fixed Speed and Torque in Open Loop Control, motor adopts to change in torque and velocity in Closed Loop control with reduced ripple. PID Controller is used for closed loop control. The presented rotary actuator and their experimental results set a new standard for SMA based new generation rotary actuators and control.
73

On Modeling and Control of Flexible Manipulators

Moberg, Stig January 2007 (has links)
<p>Industrial robot manipulators are general-purpose machines used for industrial automation in order to increase productivity, flexibility, and quality. Other reasons for using industrial robots are cost saving, and elimination of heavy and health-hazardous work. Robot motion control is a key competence for robot manufacturers, and the current development is focused on increasing the robot performance, reducing the robot cost, improving safety, and introducing new functionalities. Therefore, there is a need to continuously improve the models and control methods in order to fulfil all conflicting requirements, such as increased performance for a robot with lower weight, and thus lower mechanical stiffness and more complicated vibration modes. One reason for this development of the robot mechanical structure is of course cost-reduction, but other benefits are lower power consumption, improved dexterity, safety issues, and low environmental impact.</p><p>This thesis deals with three different aspects of modeling and control of flexible, i.e., elastic, manipulators. For an accurate description of a modern industrial manipulator, the traditional flexible joint model, described in literature, is not sufficient. An improved model where the elasticity is described by a number of localized multidimensional spring-damper pairs is therefore proposed. This model is called the extended flexible joint model. This work describes identification, feedforward control, and feedback control, using this model.</p><p>The proposed identification method is a frequency-domain non-linear gray-box method, which is evaluated by the identification of a modern six-axes robot manipulator. The identified model gives a good description of the global behavior of this robot.</p><p>The inverse dynamics control problem is discussed, and a solution methodology is proposed. This methodology is based on a differential algebraic equation (DAE) formulation of the problem. Feedforward control of a two-axes manipulator is then studied using this DAE approach.</p><p>Finally, a benchmark problem for robust feedback control of a single-axis extended flexible joint model is presented and some proposed solutions are analyzed.</p>
74

Components of reaching and grasping an object may emerge following a single minimization process

Yang, Fang January 2008 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal
75

Desenvolvimento e implementação de um sistema de controle de posição e velocidade de uma esteira transportadora usando inversor de frequência e microcontrolador

Raniel, Thiago [UNESP] 24 May 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-05-24Bitstream added on 2014-06-13T19:27:59Z : No. of bitstreams: 1 raniel_t_me_ilha.pdf: 1815527 bytes, checksum: 2b9558bcbd56601c8cbb627feda891cf (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A automação de esteiras rolantes é algo comum e importante em sistemas industriais, mas problemas práticos ainda representam desafios. Um dos desses desafios é manter a precisão em sistemas que exigem paradas sistemáticas, pois folgas mecânicas tendem a provocar variações nas posições de paradas ao longo do tempo. A aplicação de motores de indução têm se tornado comum e soluções eficientes e de baixo custo têm sido pesquisadas. Neste trabalho foi desenvolvido e implementado um sistema de controle de posição e velocidade aplicado em esteiras transportadoras utilizando inversor de frequência, microcontrolador, encoder óptico incremental e sensor indutivo. O movimento da esteira transportadora é efetuado por um motor de indução trifásico, que é acionado pelo conjunto microcontrolador – inversor de frequência. Este conjunto impõe uma frequência no estator do motor através de uma troca de mensagens entre microcontrolador e inversor de frequência (Sistema Mestre-Escravo). Para o envio e recebimento das mensagens, utilizou-se o protocolo de comunicação serial USS® (Universal Serial Interface Protocol) através do padrão RS-485. Os controles de posição e velocidade de rotação do eixo do motor fundamentam-se no sinal gerado pelo encoder óptico incremental, responsável por informar a posição do eixo do motor ao longo da trajetória, e no sensor indutivo que determina uma referência externa importante para a esteira transportadora. Para o funcionamento automático da esteira, elaborou-se um software em linguagem de programação C. Como resultado obteve-se um sistema de controle de posição e velocidade do eixo do motor de indução trifásico que apresenta bons resultados / Automated conveyors system have been largely used in industrial applications. However, there are still practical issues to be overcome. One of them is due to the system mechanical limitation which can lead to low accuracy for applications based on “stop-and-go” movements. Induction motors have been largely used in such applications and low costs solutions have been searched. In this work it was developed and implemented a system of positioning and velocity control applied to conveyors which is based on frequency inverter, microcontroller, optical incremental encoder and inductive sensor. The conveyor’s movement is made by means of a three-phase induction motor, which is driven by the couple microcontroller–frequency inverter. There are messages exchange between the microcontroller and the frequency inverter (Master – Slave configuration) which is based on the communication serial protocol USS through the RS-485 standard. The position and velocity of the motor spindle are controlled using an optical incremental encoder, which is responsible to provide the position of the trajectory, and an inductive sensor which determines the initial reference to the conveyor. The software used to control the system was developed in C language. The results show a low cost system with good results
76

Controle não linear para um veículo aéreo não tripulado : aspectos teóricos e numéricos

Silva, Carlos Augusto Nogueira da January 2018 (has links)
Orientador: Prof. Dr. André Fenili / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia Mecânica, Santo André, 2018.
77

Řízení pohybů dvouramenného žonglovacího stroje / Double arm juggling machine movement cotrol

Janeček, Jan January 2012 (has links)
The diploma thesis is a part of the project Intelligent double arm juggling machine. The project is divided into two diploma thesis. This thesis deals with the motion control of juggling arms. Information about hardware and software resources used in this project is in the first part of thesis. There is explanation of the control loop, explanation of used communication protocols and implementation of program proceeding in the second part of thesis.
78

Development of an undergraduate laboratory course in control systems

Abiakel, Elio January 2003 (has links)
No description available.
79

Revitalizace testeru regulace hydraulických obvodů / Revitalization of hydraulic circuits control tester

Korsa, Filip January 2012 (has links)
High-quality simulation of hydraulic mechanism saves the time and other costs associated with the changes of inappropriately designed circuit. The aim of this thesis is to revitalize the test rig intended for simulating hydraulic circuits in order to verify the results of the simulation program Hyvos used internally by Bosch Rexroth Company. It is expected that the simulation of the hydraulic machinery cycles under the influence of disturbances will be carry out on the test rig and measured data are compared with results of the virtual models which are designed using the mentioned software Hyvos. The work deals with the so called position and pressure control which represent the classical modes of pressing machines or hydraulic press brakes operation cycles. The parameters of the hydraulic closed-loop axis controller for electrohydraulic drives (HACD) are set using the software Bodac.
80

Robust control for manipulation inside a scanning electron microscope / Commande robuste pour la manipulation in situ microscope électronique à balayage -Robust control for manipulation inside a scanning electron microscope

Gaudenzi de faria, Marcelo 17 February 2016 (has links)
Cette thèse étudie le problème de nano-positionnement à l'intérieur d'un microscope électronique à balayage (MEB). Pour obtenir des informations de position avec rapidité et précision, une installation dédiée composée d’un vibromètre placé à l'intérieur du MEB a été mise en œuvre. Cette approche diffère de méthodes basées sur le traitement d'images, car elle permet de saisir des données en temps réel sur le comportement dynamique des structures étudiées. Dans une première étude, les perturbations mécaniques agissant à l'intérieur de la chambre à vide du microscope ont été caractérisées et leurs sources ont été identifiées. Cela a démontré comment les vibrations mécaniques externes et les bruits acoustiques peuvent influer largement sur les composants à l'intérieur du MEB par couplage mécanique, limitant ainsi la précision des manipulateurs. Dans un deuxième temps, une micro-pince du commerce a été étudiée. Une différence entre ses comportements dans l'air et dans le vide a été mise en évidence, ce qui a permis d'obtenir deux modèles dynamiques pour cet organe terminal, un pour chaque environnement. Deux lois de commande ont été proposées (commande H-infini et commande basée sur un observateur d'état étendu), afin d'obtenir en temps réel un positionnement précis dans le vide, et d'atténuer les effets des perturbations mécaniques externes. Les résultats ont été validés en simulation et expérimentalement. / This work studies the nano-positioning problem inside the scanning electron microscope (SEM). To acquire fast and accurate positional information, a dedicated setup was implemented consisting of a vibrometer placed inside the SEM. This approach differs from methods based on image processing, as it allows to capture real-time data on the dynamic behavior of structures. In a first study, the mechanical disturbances acting inside the microscope’s vacuum chamber were characterized and its sources were identified. This demonstrated how external mechanical vibrations and acoustic noises can largely influence the components inside the SEM through mechanical coupling, limiting the effective positioning precision of manipulators. Next, a commercial micro-gripper was studied, both in air and in vacuum, and the differences between its response were highlighted. This allowed to obtain two dynamic models for this end-effector, one for each environment. Two control laws were proposed (H-infinity control and Extended State Observer based control) for the system, to obtain a real-time, precise positioning in the vacuum environment and to attenuate the effects of the external mechanical disturbances. Results were demonstrated through simulation and experimental validation.

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