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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.
81

Modelagem e controle de um servoposicionador pneumático via redes neurais

Gervini, Vitor Irigon January 2014 (has links)
Visando apoiar o desenvolvimento de controladores para servoposicionadores pneumáticos, é apresentada no presente trabalho uma proposta de um procedimento baseado no uso de redes neurais para a determinação de modelos matemáticos precisos que possam ser aplicados tanto para a simulação do seu comportamento dinâmico quanto na estrutura de controladores que utilizam estratégias baseadas em modelos. No âmbito do trabalho, esse procedimento foi testado por meio de sua aplicação na identificação das forças de atrito e da relação pressão/vazão mássica nos orifícios de controle da servoválvula (que consistem nas principais não-linearidades envolvidas em tais sistemas). Além disso, determinou-se através de redes neurais a relação inversa entre as vazões desejadas e o sinal de controle da servoválvula (difeomorfismo), a qual é aplicada em técnicas de controle baseadas em modelos. Visando validar o procedimento de modelagem proposto, foram realizadas simulações em malha aberta e malha fechada, cujos resultados são comparados com os de experimentos realizados em uma bancada de testes. Com o intuito de comprovar sua eficácia em aplicações de controle, o modelo baseado em redes neurais foi utilizado no desenvolvimento de um controlador não-linear sintetizado de acordo com uma estratégia em cascata (a qual foi já testada em outros trabalhos, mostrando resultados satisfatórios quando aplicada ao controle de servoposicionadores pneumáticos). No entanto, essa estratégia apresenta dificuldades de implantação em decorrência das dificuldades associadas ao processo de identificação dos parâmetros do sistema, que são especialmente trabalhosos neste caso. As características de estabilidade em malha fechada foram analisadas por meio do segundo método Lyapunov. Os resultados experimentais em malha fechada obtidos atestam a eficácia da estratégia de controle proposta. / The development of a precise positioning system has motivated several researches in the pneumatic systems control area to overcome the problems caused by these nonlinearities, by appropriate feedback control algorithms. In this work it is proposed a methodology based on neural networks to achieve accurate mathematical models that can be used in simulation as in controllers techniques based on models. This methodology was tested through its application in identifying the phenomenon of friction and the relationship pressure/mass flow through servo valve orifices control holes. Furthermore, using neural networks, the inverse relationship between the desired flow rates and control signal of servo valve (diffeomorphism), which is applied in various control techniques based on models, was determined. To evaluate the proposed modeling methodology, simulations were done in open and closed loop, and the results were compared with experiments conducted on a real pneumatic servo positioning system. A neural network based model was used to develop a nonlinear controller according to a cascade strategy with friction compensation (which has been tested on other studies showing satisfactory results when applied to pneumatic servo positioning control). The cascade control strategy, despite showing a good performance in trajectory tracking, presents significant difficulties in implementation due mainly to difficulties associated with the system parameters identification process, which are especially expensive. The characteristics of the closed loop stability were analyzed by Lyapunov method. The experimental results obtained in closed loop attest the efficiency of the proposed control strategy.
82

Desenvolvimento e analise de estrategias de controle colaborativo para cadeiras de rodas / Development analyses of collaborative control strategies for wheelchair

Lombardi Junior, Arley de Barros 11 April 2005 (has links)
Orientador: Franco Giuseppe Dedini / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-05T16:15:48Z (GMT). No. of bitstreams: 1 LombardiJunior_ArleydeBarros_D.pdf: 5366373 bytes, checksum: 0982b8d5bebb123f92dc4438f65e3f2c (MD5) Previous issue date: 2005 / Resumo: Esta tese consiste no desenvolvimento de estratégias de controle para o sistema de motorização servo assistido para cadeirantes. O sistema combina as vantagens do sistema de propulsão motorizado como aumento da acessibilidade e mobilidade com as vantagens do sistema manual que é o aumento da capacidade muscular e cardiovascular. Este sistema de motorização atua somente quando a força de propulsão exercida pelo usuário é superior à um determinado limite, o que evita o desenvolvimento de lesão por esforço repetitivo. Metodologicamente foi definido um modelo biomecânico para análise dos esforços do ciclo de propulsão aliado a um modelo dinâmico do sistema para análise e simulação das rotinas de controle propostas. Para geração das estratégias de controle utilizou-se a metodologia de projeto axiomático integrado as estruturas de controle de sistemas multi-agentes, sistemas subsumption e lógica nebulosa. As rotinas foram testadas no modelo dinâmico onde foi possível determinar sua eficiência. Finalizando o processo de concepção do sistema de controle foi construído um programa para simulação do mesmo e um protótipo em escala controlado por este programa. Concluindo o trabalho apresenta o primeiro desenvolvimento de controle para motorização servo assistida e também a primeira utilização de metodologia de projeto axiomático para desenvolvimento de estratégias de controle / Abstract: The aim of this dissertation is to develop control strategies for servo-assisted motorization. The system brings the power wheelchair advantages because it increases the accessibility and mobility, but it also brings manual wheelchair advantage that is the opportunity to increase the muscular and cardiovascular capacity. Thus the servo assisted wheelchair is a therapeutic wheelchair which allows the user increases his physical and pulmonary capacity without risk of injury for repetitive effort. The motorization only turns on when the propulsion force applied by the user is higher than a specific value. Methodologically was defined a biomechanical model for analysis of the efforts during the propulsion cyc1e. This model was associated with a wheelchair dynamic model. The new model allows the analysis and simulation of the control strategies proposed. For control strategies generation it was used methodology axiomatic design integrated with the structures of multi-agents control systems, subsumption systems and fuzzy logic. The strategies had been tested using the dynamic model and it was possible to determine its efficiency. It was developed a program for mathematical simulation and a prototype controlled by this program for testing some results. Conc1uding the work presents the first development for control of servo assisted motorization and it is the first application of axiomatic design methodology for control strategies development / Doutorado / Mecanica dos Sólidos e Projeto Mecanico / Doutor em Engenharia Mecânica
83

Vliv nastavení regulátoru servopohonu na energetickou náročnost / Influence of servodrive controller settings on energy consumption

Kura, Ondřej January 2021 (has links)
The aim of this work is to investigate the energy consumption of the servo drive at different control settings. First, the theoretical part describes the servo drive as a mechatronic system with subsequent disassembly in terms of losses and efficiency, where all the losses that occur in the servo drives are defined. Subsequently, the theoretical part concludes with a chapter on controllers, thanks to which it is possible to control servo drives and describes their influence on the resulting control. In the practical part, a model of a DC motor with a linear axis and regulation was first created in the Simulink program. Subsequently, the Matlab program defined motion with linear acceleration and motion using S-curves, which controlled the model. Then the model was measured at different settings of the controllers and the resulting waveforms together with the energy values were compared with each other. In the second half of the practical part of this work, a real servo drive was then measured with a subsequent comparison with the created model. In this comparison, the resulting waveforms and energy values were also compared. The result of this work is then to determine the effect of changes on the resulting control, which are made in the controller settings. The functional models can then be used to determine how the various servo drives will behave under the given control conditions.
84

Časovač pro RC modely / Timer For RC Models

Fišer, Ondřej January 2018 (has links)
This paper describes complete design of timer for RC models. Described timer has three PWM outputs. With these outputs it is possible to connect two independent servo-motors and engine controller. 1 signal. The whole is controlled by 8-bit microprocessor. The time records are stored in external EEPROM, that can be programmed using I2C. Paper further discuss design of programming, which can be easily programmed the memory of EEPROM by the PC or smartphone. The goal of this paper is to design and build high quality RC timer with accessories.
85

Síťový napájecí modul pro servopohon / Power supply module for servo-drive

Kudláček, Pavel January 2020 (has links)
The aim of the diploma thesis is to theoretically design and to put the mains power supply module for two-axis servo amplifier TZG 560 with the total power 28kW for the company TG Drives into practice. The analytical design of the power part with the braking circuit, the calculation of power components’ heat balance, EMI filter design and realization of measuring, controlling and indication circuits are described in the thesis. In addition, the mechanical device construction, structure of the controlling program and the results obtained in the verification process of the module functionality are presented.
86

Optimalizace aerodynamického odlehčení směrového kormidla letounu L-410NG / Optimization of L-410NG airplane rudder aerodynamic balance

Pištěcká, Kateřina January 2020 (has links)
The subject of this diploma thesis is a design of rudder aerodynamic balance and its optimization with regard to control forces and vertical tail and fuselage loading in critical flight modes – critical engine failure.
87

Řídicí jednotka pro humanoidní robot / Control Unit for Humanoid Robot

Florián, Tomáš January 2009 (has links)
The main goal of this project is to understand broadband sold Robonova-I humanoid robot and to design new improvements. The thesis is divided into five main chapters: The first of them (Robonova-I) is concerning the kit of Robonova-I, its completion and control possibilities. In details it deals with used servo motors, their operating and compares them. The next chapter is concerning the design of the control unit along with description of architecture of the processor and control possibilities with demonstrational board. In third there is a software solution of particular methods and commands which control the unit with demonstrational board. Chapter “The Design of Printed Circuit Board” describes facilities of the designed printed circuit board. The last chapter describes the final program for robot control through the use of computer and some of the algorithms by means of which the robot controls the microprocessor.
88

Sun Tracking System

Dandu, Sai Charan Reddy, Sarla, Anish January 2022 (has links)
Solar energy is a clean energy source which has a minimal impact on the environment than other forms of energy. Solar energy is now widely used in a variety of applications. Although solar energy is widely used, the efficiency of converting solar energy into electricity is insufficient since most solar panels are installed at a fixed angle and the fixed solar panels do not aim directly towards the sun due to the earth’s constant motion. Solar panels are very expensive for families or businesses that consume more energy than usual, as they require several solar panels to generate enough power. The main objective of this project is to build a working model so that to increase the efficiency of power output taken from solar panel by continuously tracking the sun’s rays through out the day and aligns the solar panel orthogonal to the sun. To develop a model that benefits people by producing more solar energy with fewer solar panels. In order to overcome this problem we come up with a solution through Arduino Uno system which consists of four LDR sensors which are responsible for the detection of the light intensity of the sun’s rays. Two micro servo motors are used for movement of the solar panel in azimuth and elevation direction since it is a dual axis tracking system. A solar panel is the core part we use in this model for the conversion of solar energy into electrical energy. The LCD displays shows the power output of the solar panel. The proposed system is a dual axis tracking system that actively tracks solar radiation and adjusts the panel so that the sun’s rays are perpendicular to it, maximizing the solar panel’s power output. The LCD display shows the power output of the solar panel. By this project, we can say that dual axis tracking system we built can track the sun’s rays and increases the power output of solar panel. The manual effort for changing the solar panel according to the sun position can be avoided.
89

Positioning and tracking using image recognition and triangulation

Boström, Viktor January 2021 (has links)
Triangulation is used in a wide range of applications of position estimation. Usually it is donebymeasuring angles by hand to estimate positions in land surveying, navigation and astronomy.Withthe rise of image recognition arises the possibility to triangulate automatically. The aim ofthis thesisis to use the image recognition camera Pixy2 to triangulate a target i threedimensions. It is basedon previous projects on the topic to extend the system to estimatepositions over a larger spaceusing more Pixy2s. The setup used five Pixy2s with pan-tilt kitsand one Raspberry Pi 4 B. Somelimitations to the hardware was discovered, limiting the extentof the space in which triangulationcould be successfully performed. Furthermore, there weresome issues with the image recognitionalgorithm in the environment positioning was performed.The thesis was successful in that it managesto triangulate positions over a larger area thanprevious projects and in all three dimensions. Thesystem could also follow a target’s trajectory,albeit, there were some gaps in the measurements.
90

Ovládání robotického manipulátoru mikrokontrolérem / Robotic Manipulator Controlling Using Microcontroller

Zemánek, Martin January 2007 (has links)
This master's thesis deals with control robotic manipulator ROB 1-3 using common joystick and microcontroller HC08 NITRON or HC08 LJ12. The goal of this work was creation of module for controlling axes position of servos included in robot by analog signal coming from connected joystick. There are formed possible suggestions about connecting individual parts together for both autonomous and version using development kit. Programming code suggestion is based on these connections during further development. The limitations of using it are described in analysis and final results are shown in statistics results.

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