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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

Development Of A 3 Axes Pc Numerical Control System For Industrial Applications

Basar, Feza 01 January 2003 (has links) (PDF)
In this study, a three-axes PC numerical control system for industrial applications has been developed. With this system, fast and cheap prototyping of designed objects can be realized. The system consists of software and a hardware which includes an XYZ positioning table and three step motors controlling this table. A proper drive circuit for the stepper motors is utilized. The software digitizes two dimensional drawings of three dimensional objects and generates the control signals for the XYZ positioning table. The software is developed under Microsoft Studio Visual Basic 6.0 environment regardless of the OS of the PC. The parallel port of the PC has been utilized for generating the necessary control signals for the stepper motors.
2

Žingsninio variklio dinamikos tyrimas / Investigation of dinamic of step motor

Palevičius, Valdemaras 23 June 2006 (has links)
In work research of dynamics of the step motor is executed. Types step motor, ways of management, a design and parameters are described. Сonsistent to requirements and inquiries the software package „Mathlab R6.5“ is chosen. Using a software package „Mahtlab R6.5“ the model of the motor has been made and many experiments are executed. Schedules of transient and the frequency characteristic are considered, changing factor of attenuation and the moment of inertia of the step motor. The conclusion and theoretical results show opportunities of functioning of the step motor. Structure: introduction, analytical part, investigation part, conclusions and suggestions, references.
3

[en] THE RESEARCH AND DEVELOPMENT OF AN DRIVER FOR STEP MOTOR OPERATING IN LOW TENSION / [pt] PESQUISA E DESENVOLVIMENTO DE UM ACIONAMENTO PARA MOTOR DE PASSO OPERANDO EM BAIXA TENSÃO

MARCELO NEVES BARRETO 20 September 2005 (has links)
[pt] A pesquisa e desenvolvimento de um acionamento para motor de passo operando em baixa tensão apresenta o desenvolvimento de um mecanismo de acionamento para motores de passo de 2 fases, destinado a operar na faixa de 12 a 18 V, tornando-se muito útil para automações em veículos, embarcações ou robôs que operam com baterias. O acionamento desenvolvido implementa o controle da corrente via chopper, como é usual nos acionamentos de motores de passo. Mas, ao contrário do usual, o tempo do ciclo ativo da onda responsável por ativar a corrente nas fases é pré-programado em microcontroladores, evitando-se a instabilidade e criticalidade típica dos circuitos responsáveis pelo sensoramento da corrente e sua realimentação para controle do ciclo ativo. Outro aspecto inovador do trabalho foi a utilização do integrado TD340 da ST Microeletronics, desenvolvido para utilização no controle de motores de corrente contínua, e que está sendo empregado com motores de passo. Os resultados experimentais apresentados no trabalho confirmam a adequação e utilidade do acionamento desenvolvido, tornando-o compacto e robusto. / [en] The research and development of an driver for step motor operating in low tension presents the development of a chopper driver intended to drive 2- phase step motors. The driver was designed to operate between 12 and 18 V which makes it very attractive for automations in vehicles and robots which carry their own batteries. Contrary to the usual design, where the duty cycle of phase current is controlled by sensing this current and feed backing its value to the chopper, the present driver uses fixed value duty cycle, which varies step by step according to a table stored in the memory of a microcontroller. In so doing, we avoid most of the troubles due to noise and voltage fluctuation in the feedback line, typical of usual drivers. Another innovation presented in this work, is to use the H-Bridge MOSFET driver TD340 in driving step motors. This component, manufactured by ST Microeletronics, was originally designed for driving CC motors. Experimental results presented in this work show that the driver developed in this research has performed successfully according with the intended goal.
4

Měření kvantové účinnosti optoelektronických prvků a návrh laboratorního měřícího systému / Quantum efficiency measurement of optoelectronic components and development of experimental equipment

Lipr, Tomáš January 2011 (has links)
This thesis deals with the issue of quantum efficiency measurement of optoelectronic devices. The physical nature of silicon solar cells is explained here. In addition, the quantum efficiency as a concept is introduced. There is also discussed the influence of a solar cell semiconductor structure on the quantum efficiency itself. Furthermore, the thesis is focused on the design of an experimental set-up for automated measurement and data acquisition. The final realization of the step motor control unit is described in detail. It includes local and/or remote operations, design and development motivation. The next chapter is dedicated to analysis of the Matlab source code for remote operation, data acquisition and presentation. The final part of the thesis gives attention to experiments with real structures, not only the solar cells. The obtained results of analyzed measurements are presented at the conclusion.
5

Instrumentação eletrônica de apoio para um sistema de epitaxia por feixes moleculares / Electronic hardware development for molecular beam epitaxy.

Arakaki, Haroldo 29 March 1994 (has links)
Neste trabalho é apresentado o desenvolvimento de instrumentação eletrônica para controle e automação de um sistema de crescimento de semicondutores por Epitaxia por Feixes Moleculares. Envolve uma variedade de circuitos analógicos e digitais como: um módulo de aquisição de dados e controle baseado em uma UCP Z-80, contendo algumas interfaces digitais e analógicas multiplexadas, e comunicando-se com um microcomputador através de uma interface serial. Envolve ainda o desenvolvimento de controladores de temperatura analógicos tipo P.I.D., atuação por motores de passo e circuitos de condicionamento de sinal. / In this work is presented the development of electronic instrumentation for automation and control of a Molecular Beam Epitaxy semiconductor growth system. A variety of analog and digital instrumentation circuits have been designed and implemented, including a data acquisition and control system based on a Z-80 CPU, which controls some multiplexed digital and analog interfaces and talks to a microcomputer using serial communication. Other circuits have been also developed, including analog temperature controllers, stepper motor actuators and circuits for signal conditioning.
6

Instrumentação eletrônica de apoio para um sistema de epitaxia por feixes moleculares / Electronic hardware development for molecular beam epitaxy.

Haroldo Arakaki 29 March 1994 (has links)
Neste trabalho é apresentado o desenvolvimento de instrumentação eletrônica para controle e automação de um sistema de crescimento de semicondutores por Epitaxia por Feixes Moleculares. Envolve uma variedade de circuitos analógicos e digitais como: um módulo de aquisição de dados e controle baseado em uma UCP Z-80, contendo algumas interfaces digitais e analógicas multiplexadas, e comunicando-se com um microcomputador através de uma interface serial. Envolve ainda o desenvolvimento de controladores de temperatura analógicos tipo P.I.D., atuação por motores de passo e circuitos de condicionamento de sinal. / In this work is presented the development of electronic instrumentation for automation and control of a Molecular Beam Epitaxy semiconductor growth system. A variety of analog and digital instrumentation circuits have been designed and implemented, including a data acquisition and control system based on a Z-80 CPU, which controls some multiplexed digital and analog interfaces and talks to a microcomputer using serial communication. Other circuits have been also developed, including analog temperature controllers, stepper motor actuators and circuits for signal conditioning.
7

Systém automatického ladění pro sedmistrunné kytary / The automatic self tuning system for seven-string guitars

Jeřábek, Vojtěch January 2017 (has links)
The thesis describes a realization of the automatic self tuning system for sevenstring guitars. There are comparisons of commercial and uncommercial solutions for six-string guitars. There is also evaluation of useful parts for seven-string guitars. Thesis contains a description of a requirements for individual parts and a control software with respect on real guitar properties and used computing algorithm. In the second part of thesis, there is a description of final system design and its realisation including the control software. This is also related with testing of the entire system.
8

Разработка принципов построения схем зубофрезерного станка с безгитарным приводом : магистерская диссертация / Working out principles of hobbing machines schemes design with gear free drive

Белянцева, И. В., Belyantseva, I. V. January 2017 (has links)
Relevance of this research is conditioned by necessity of increasingmetalworking machines efficiency in modern machinery building. One of the main constructive elements of gear milling machines is mechanical gear train (speed gear train, feed gear train, dividing gear train, differential gear train). The adjustment of all these shaping moves is important objective. Though mechanical gear trains do not provide high tooling precision.That’s why precision can be increased by developing ways of replacing mechanical gear trains by hydraulic and electronic analogs. These ways were poorly considered before. Goal of the work: analyzing of existing principal gear milling machine schemes, analyzing of possible ways of shaping moves electronic adjustment, descrying of various frequent divisor structures. Calculation unevennessof impulses following for divisors, that work in different codes and improving schemes of machines with electric step motor and adjustable electric motor by way of increasing tooling precision. Master’s dissertation consists of 6 chapters: Chapter 1: Modern gear milling machines principal schemes. This chapter describes function of gear trains, structure of cutting moves in gear milling and schemes of existing gear milling machines with mechanical and electronic gear trains. Chapter 2: Analysis of ways and tools of electronic (“Non-gear-train”) adjustment of machine’s shaping moves. This chapter describes ways of coordinating an adjustable electronic motor and electronic step motor, ways of coordinating two adjustable electronic motors. Chapter 3: modern constructions of impulse frequency divisors. Schemes andfunctioning of divisors. This chapter analyze various schemes of frequency divisors, ways of divisor selecting for gear milling machine, calculating the unevenness of impulses, transferring with divisors for various codes. Chapter 4: Improvement of gear milling machines with electric step motor Suggestion of improved kinematic schemes for electric step motor milling machines. Chapter 5: Improvement in schemes of gear milling machines with adjustable electric motor. Suggestion of improved kinematic schemes for adjustable electric motor milling machines. Chapter 6: Work out of technical proposal for gear milling machine with adjustable electric motor. Chapter contains selection of electric motor for chosen kinematic scheme with electronic gear train, kinematic and robustness calculation, comparison of mechanical and electronic gears’ precision. Master’s dissertation consist of 128 pages, containing demonstrational materials, calculations and text description, and 17 graphic documents. / Актуальность темы исследования обусловлена необходимостью повышения эффективности металлорежущих станков в современном машиностроении. Одними из основных конструктивных элементов зубофрезерного станка являются механические гитары (скоростей, подач, деления, дифференциала). Важной задачей является согласовать всеэти формообразующие движения. Но механические гитары не обеспечивают высокой точности обработки. Поэтому были разработаны способы повышения точности путем замены механических гитар гидравлическими и электронными. Ранее эти способы были рассмотрены поверхностно. Цель работы: проведение анализа существующих принципиальных схем зубофрезерных станков, анализ возможных способов электронного согласования формообразующих движений, рассмотрение различных конструкций делителей частоты, расчет неравномерности следования импульсов для делителей, работающих в различных кодах, и совершенствование схем станков с шаговым и регулируемым электроприводами для повышения точности обработки. Магистерская диссертация состоит из 6 глав: Глава 1: Принципиальные схемы современных зубофрезерных станков В главе рассматривается назначение гитар, структура рабочего движения при зубофрезеровании, а также существующие кинематические схемы зубофрезерных станков с механическими и электронными гитарами. Глава 2: Анализ способов и средств электронного («безгитарного») согласования формообразующих движений в станке В главе описываются способы согласования работы регулируемого и шагового приводов, и согласование работы двух регулируемых приводов. Глава 3: Современные конструкции делителей частоты импульсов, их устройство и работа В главе анализируются различные конструкции делителей частоты, также производится выбор делителя, применительно к зубофрезерному станку. Производится расчет неравномерности следования импульсов, передаваемых через делители для различных кодов. Глава 4: Совершенствование зубофрезерных станков с шаговым электроприводом Предлагаются усовершенствованные кинематические схемы станков с шаговыми электроприводами. Глава 5: Совершенствование схем зубофрезерных станков с регулируемыми электроприводами Предлагаются усовершенствованные кинематические схемы станков с регулируемыми электроприводами. Глава 6: Разработка технического предложения зубофрезерного станка с регулируемыми электроприводами В главе выбирается электродвигатель для выбранной кинематической схемы с электронной гитарой, производится кинематический и прочностной расчет и сравниваются по точности механическая и электронная гитары. Магистерская диссертация выполнена на 128 страницах, содержащих демонстрационные материалы, расчеты и описание, и включает 17 графических документов.
9

Разработка принципов построения малогабаритного снегоболотохода с дистанционным управлением : магистерская диссертация / Development of design principles for small-size remotely controlled snow-and-swamp mobiles

Шонохова, Н. А., Shonokhova, N. A. January 2018 (has links)
Выпускная квалификационная работы выполнена на тему «Разработка принципов построения малогабаритного снегоболотохода с дистанционным управлением». Расчетно-пояснительная записка содержит 198 листов, 90 рисунков, 16 таблиц, 11 источников, 42 приложения. Объектом разработки является малогабаритный снегоболотоход с дистанционным управлением, предназначенный для инженерно-изыскательских работ. Цель работы – разработка принципов построения малогабаритного снегоболотохода с дистанционным управлением, в том числе разработка новых узлов, выбор из ранее представленных, модернизация и реконструкция элементов, разработанных для других машин. В результате проведенной работы спроектированы 3 шнековых движителя, 4 подвески, 2 системы управления, также рассмотрены блоки задания скорости, кольцевые распределители импульсов и преобразователи «Код-напряжение». В проекте также рассмотрены вопросы безопасности труда, радиационная безопасность и природопользование и охрана окружающей среды. В разделе технико-экономических показателей приведены единовременные, текущие и приведенные затраты. / The goal of the research was to justify the selection of various structural elements and control systems on the basis of both design parameters and the analysis of assigned tasks. Thus, a number of existing designs of machines, propellers and suspensions were considered in the course of the study, all of which could be used for different purposes: for example, it is more rational to utilize motor-in-wheel propellers to glide over the water, since those are most lightweight and waterproof of all, and to choose a spring suspension – since it contains the minimal number of elements which could fail in the water medium. As to the systems of control, the selection of their control blocks is made on the criteria of reliability, since it is necessary to ensure no-failure operation of the system as a whole. As a result of the work, 3 screw propellers, 4 suspensions, 2 control systems were designed, and a few speed assignment blocks, circular distributors of impulses and number-to-voltage converters were considered. The project also analyses the problems of work safety, radiation safety, conservation and environment control. The section on project feasibility cites nonrecurring, current and reduced costs.

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