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

Personal computers and portable electronics continue to rapidly advance and integrate into our lives as tools that facilitate efficient communication and interaction with the outside world. Now with a multitude of different devices available, personal computers are accessible to a wider audience than ever before. To continue to expand and reach new users, novel user interface technologies have been developed, such as touch input and gyroscopic motion, in which enhanced control fidelity can be achieved. For users with limited-to-no use of their hands, or for those who seek additional means to intuitively use and command a computer, novel sensory systems can be employed that interpret the natural electric signals produced by the human body as command inputs. One of these novel sensor systems is the myoelectric detection circuit, which can measure electromyographic (EMG) signals produced by contracting muscles through specialized electrodes, and convert the signals into a usable form through an analog circuit. With the goal of making a general-purpose myoelectric detection circuit platform for computer interface applications, several electrical circuit designs were iterated using OrCAD software, manufactured using PCB fabrication techniques, and tested with electrical measurement equipment and in a computer simulation. The analog circuit design culminated in a 1.35” x 0.8” manufactured analog myoelectric detection circuit unit that successfully converts a measured EMG input signal from surface skin electrodes to a clean and usable 0-5 V DC output that seamlessly interfaces with an Arduino Leonardo microcontroller for further signal processing and logic operations. Multiple input channels were combined with a microcontroller to create an EMG interface device that was used to interface with a PC, where simulated mouse cursor movement was controlled through the voluntary EMG signals provided by a user. Functional testing of the interface device was performed, which showed a long battery life of 44.6 hours, and effectiveness in using a PC to type with an on-screen keyboard.

Thesis deals with the theoretical design of an automatic control system for the aquarium and following simulation software environment Proteus ISIS. Due to simulation program can verify the behavior of the microprocessor in the specified functions, the correctness of electrical connections and errors in source code. The second part is analysis of commercial systems, their characteristics and applications. Apart from available commercial systems, there is a basic overview of commonly used peripherals in the aquarium, including their comparison and evaluation. Furthermore, the implementation of a complex system is done and the procedures and methods needed to set up the system are described. This topic also deals with cooling and reliability tests.

Purpose of this dissertation is to explore control techniques of PMSM motors and the design of a complex solution of sensorless control across a wide range of speed and torque. The proposed solution supports industrial implementation of different types of end equipment which use a PMSM motor. The work covers a thorough analysis of position and speed estimation. The Control structure is based on field oriented control technique, processes estimated quantities, and optimizes motor conditions to achieve maximum efficiency, start-up torque, and speed. The work discusses how the solution complies with the latest IEC standards. Compliance with these standards requires adapting the sensorless control technique and field oriented control structure. The elimination of a rotor position sensor and a temperature sensor measuring winding temperature requires development of techniques in software for blocked rotor detection and overload detection. The proposed solutions, which have been granted US patents, are explained in this work and utilize the unique features of an NXP microcontroller optimized for motor control applications. The achieved results are demonstrated on real industrial applications.

This semestral project is concerned with remote control PTZ camera using the wireless controller, and the controller design including design documents. The controller will be composed of the signal converter, microcontroller and RF module. Control data to the controller will come via link RS485 and controller will be able to communicate using the following protocols-Ernitec and Pelco. The proposed controller, according to data from the manufacturer to have a range of up to 500m. This parameter and also other transmission parameters confirm in the diploma thesis which will focus the actual implementation of the controller.

In the thesis the design of the Data Storage System (DSS) is proposed with the respect to the V-Model methodology. The design is based on users requirements, from which the system requirements are created and the technical specification of the DSS is developed. In the technical specifications the functionality of the DMM and HMI DSS subsystems are described and sub-system requirements are assigned to them, then they are subdivided and assigned to individual DMM (Data memory module) and HMI hardware items. Moreover, requirements are analyzed on hardware items, specific electronic components, are selected and implemented into the block design of the DMM hardware. Based on the block design of hardware, the hardware of the DMM subsystem is designed, selectively simulated and implemented along with the printed circuit board. On the implemented hardware of the DMM subsystems measurements are performed in order to verify the basic functionality of the hardware and the calculated, assimilated and measured values are compared as well. At the end of the thesis there is a short description of the implementation of the software design and its use for basic initialization of the selected processor, together with the verification of its basic function - measuring the frequency of the internal clock sources and the clock domains. The work is completed by sending a message of defined parameters to the selected communication line and sapling it by an oscilloscope, so that the basic function of the DMM subsystem is verified.

The focus of this thesis is a development of an electronic guiding unit for a mount of an astronomical telescope allowing observations of artificial satellites orbiting the Earth. It contains a theoretical study of methods developed for the description of positions of objects observable on the celestial sphere, including systems used for storage of this information and regaining it in order to point the telescope in a specific direction. The work includes an analysis of the present supply of commercial devices, followed by a detailed description of the design developed here and its components. Finally, there is outline of possibilities of a future development of the system, focusing on software components.

This thesis describe development and realization of transistor tester based on AtMega microcontroller. Developed equipment should be used by DIY users or students in university workshop to verify transistor functionality and measure basic characteristics. Equipment should be easily manufacturable in a piece quantity with reasonable costs.

The subject of this thesis is a design of a precision dual channel laboratory power supply with output voltage range from 0 to 30 V and adjustable current limit up to 1 A. The proposed solution is based on linear regulators and input voltage switching system to minimize power dissipation. Galvanically isolated channels of the power supply share the same microcontroller that processes the user inputs. Microcontroller code allows the calibration of the device or it’s communication with computer. The cover of the device is designed with good cooling performance and 3D printing manufacturing method in mind. The properties of the designed laboratory power supply are verified by the final test measurements.

The thesis is aimed on construction of solar panel powered datalogger of environmental values. The thesis begins by research of commercial dataloggers. Then the concept of datalogger was created. Then the electronics of datalogger was designed. Datalogger is built as a system driven by microcontroller. The microcontroller reads data from sensors, writes data to memory card and sends data to Czech radiocommunications cloud by LoRa technology. Then the data are resend to MySQL database. Program for microcontroller was made in C language. Configuration of datalogger is done through USB interface by PC application which was created in C# language. For visualisation of measured data ASP.NET Core application was created.