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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

Sensorless Control of a Hybrid Stepper Motor

Karlsson, Lina January 2016 (has links)
Electrical drives are widely used in today’s society. They can be found in bothhousehold products and in the industry. One application where electrical drivesare used is in robots for mowing lawns. In the studied robots the motors in theelectrical drives used for propulsion are Brush Less Direct Current motors, BLDCmotors.The BLDC-motor has its maximum torque at high speeds and thereforea gearbox is needed. The gearbox is space consuming, add costs and consists ofmechanical parts that wear during use. Of interest is therefore to investigate ifthere are other electrical drives which can be used for propulsion.A motor who has its maximum torque at low speeds is the Stepper motor, andtherefore it is of interest to investigate if a stepper motor could replace the BLDCmotor.A drawback with the stepper motor is that it always consumes maximumcurrent and therefore a current controller is beneficial. Together with currentcontrol, speed control is needed to make the robot run at desired speed. To beable to perform an accurate current and speed control feedback from the motor isneeded. Information about the rotor angle and velocity can be used for the speedcontrol and the load angle can be used for the current control since the current isproportional to the load torque.To estimate the rotor angle and velocity a model has been developed. Themodel is based on fundamental electrical and mechanical equations and neglectsthe current and position dependence of the inductance and flux linkage. To completethe model three motor parameters, the maximum detent torque Tdm, themaximum flux linkage  m and the friction constant B was determined. Parameterdetermination was done by linear regression and by using an Extended KalmanFilter, EKF. The result of the parameter determination were Tdm = 0.2152 Nm, m = -0.002854 Vs/rad and B = 0.01186 Nms/rad.The model is used in an EKF to estimate the rotor angle and angular velocity.The result of the implemented EKF seems promising. When making the rotortake a step in velocity from 3.927 rad/s to 7.85 rad/s the EKF estimates the stateswith only a small bias: 0.02 rad for the angle, 0.3 rad/s for the velocity, 0.005 Afor phase a current and 0.0004 A for phase b current.To estimate the load angle the Sliding Discrete Fourier Transform is used. Theexpected relation between the load torque and load angle is sinusoidal. The loadangle is calculated from data where the external load is between 0-2.5 Nm. Inthat area the load angle shows the expected sinusoidal appearance and the loadangle is in the area between 0.1 and 0.45 rad. At 3 Nm the rotor stalls and it isshown that the load angle varies between 0 and 2 rad when the rotor is stalled.
2

Systém pre sledovanie pohybujúcich sa objektov / Moving objects monitoring system

Orolin, Jakub January 2019 (has links)
The presented thesis deals with the design of a system capable of tracking the moving objects. The output of the thesis is the prototype layout of the device. Facility will be physically placed between the camera and the tripod in the dissertation and tested in real conditions. The role of this system is to automatically rolling the camera up the selected moving object.
3

Řízení CNC pískovačky / CNC milling machine control

Hanulík, René January 2020 (has links)
The diploma thesis clarifies the issue of creating inscriptions on stone slabs. It describes some types of sensors, actuators, their physical principles and possibilities of their use. The work mentions the limitations and specifics of sandblasting, design solutions and implementation of equipment for patternless sandblasting.The functionality of the device is demonstrated and verified on illustrative examples.
4

Návrh speciálního anténního rotátoru / Design of special antenna rotator

Půhoný, Jan January 2010 (has links)
This master's thesis deals with design electronics for an antenna rotator in two axis. There are designed and implemented drivers for two stepper motors. Was also designed and implemented control panel that allows manual control the rotator and remote control by PC via USB. At the same time created software for control panel and PC application for easy operation.
5

Utvecklingsmetodik för styrning av stegmotorer med en FPGA / Development methodology for control of stepper motors with a FPGA

Håkansson, Svante January 2013 (has links)
Detta examensarbetet har utförs vid Calmon Stegmotorteknik AB (CST) för att utveckla FPGA delen av derasutvecklingsplattform. Denna rapport avser att ge tankar och teori om utvecklingsmetodiken av detta arbetet. CST:s utvecklingsplattform ska användas för videobehandling, motorstyrningar samt mät och instrumentapplikationer. Dock berör detta arbetet endast de funktioner som behövs för att kunna använda utvecklingskortet för motorstyrningar. Detta innefattar implementationer av PWM, mikrostegningstyrning samt motorstyrning med hjälp av fullsteg och halvsteg. / This Bachelor thesis have been done for Calmon Stegmotorteknik AB (CST) to develop the FPGA part of their developmentplatform. This thesis is created to give thoughts and theory about the development methodology used in this project. CST:s development platform will be used for video processing, motor controls and also measurement and instrument applications.This thesis however concerns only the functions that is needed for using motor controls on the development board. Which includes implementation of PWM, microstepping control and also motor control with help of fullstep and halfstep.
6

Automatiserad provrörskarusell : Elektronikkonstruktion och utvärdering / Automated sample tube mover

Rosenfeld, Carl January 2010 (has links)
<p>Den här rapporten beskriver arbetet med en automatiserad provrörsförflyttare. Det är ett examensarbete som har gjorts på företaget Q-linea AB. En karuselliknande konstruktion med en stegmotor användes för att flytta prover mellan ett antal positioner. En mikrokontroller som hanterar styrning och sensordata har programmerats i C. LabVIEW och en USB-kamera har använts som hjälp till att göra utvärderingar och tester av systemet. Målet var att konstruera en prototyp som uppfyllde de precisionskrav och tidskrav som ställdes, vilket också uppnåddes. Rapporten beskriver arbetsgången och avslutas med rekommendationer för fortsatt arbete. Rapporten innehåller en teoridel som kan användas till hjälp för att konstruera liknande system, d.v.s. roterande positioneringstillämpningar.</p> / <p>This thesis describes the work of an automated sample tube mover. This is a degree project and has been done at the company Q-linea AB. A carousel similar construction with a stepper motor has been designed for the task to move samples between a numbers of positions. A microcontroller has been programmed to control the movements and handle sensor data. LabVIEW have been used together with an USB-camera in order to do evaluations and tests of the system. The goal was to design a prototype that fulfills the demanded requirements of precision and timing, which also was achieved. The thesis describes the work process and concludes with recommendations for further work.</p>
7

Automatiserad provrörskarusell : Elektronikkonstruktion och utvärdering / Automated sample tube mover

Rosenfeld, Carl January 2010 (has links)
Den här rapporten beskriver arbetet med en automatiserad provrörsförflyttare. Det är ett examensarbete som har gjorts på företaget Q-linea AB. En karuselliknande konstruktion med en stegmotor användes för att flytta prover mellan ett antal positioner. En mikrokontroller som hanterar styrning och sensordata har programmerats i C. LabVIEW och en USB-kamera har använts som hjälp till att göra utvärderingar och tester av systemet. Målet var att konstruera en prototyp som uppfyllde de precisionskrav och tidskrav som ställdes, vilket också uppnåddes. Rapporten beskriver arbetsgången och avslutas med rekommendationer för fortsatt arbete. Rapporten innehåller en teoridel som kan användas till hjälp för att konstruera liknande system, d.v.s. roterande positioneringstillämpningar. / This thesis describes the work of an automated sample tube mover. This is a degree project and has been done at the company Q-linea AB. A carousel similar construction with a stepper motor has been designed for the task to move samples between a numbers of positions. A microcontroller has been programmed to control the movements and handle sensor data. LabVIEW have been used together with an USB-camera in order to do evaluations and tests of the system. The goal was to design a prototype that fulfills the demanded requirements of precision and timing, which also was achieved. The thesis describes the work process and concludes with recommendations for further work.
8

Geodezinių prietaisų pozicionavimo sistemos tyrimas / Analysis of Stepper Gear Used in Geodesic Equipment

Armonas, Simas 08 July 2009 (has links)
Baigiamajame magistro darbe nagrinėjama ir modernizuojama Geodezijos institute naudojamo įtaiso, skirto geodezijos prietaisams kalibruoti, žingsninė pavara. Stende naudojama pavara nebeatitinka reikalaujamo tikslumo, ir neišvysto reikiamo greičio. Darbo tikslas – modernizuoti pozicionavimo pavarą (padidinti jos greitį ir tikslumą). Teorinėje dalyje aptariamas geodezijos prietaisų kalibravimo stendo veikimo principas, naudojama kalibravimo metodika, atliekamas žingsninio variklio dinaminių charakteristikų skaičiavimas. Eksperimentinėje dalyje pateikiamos principinė ir funkcinė modernizuotos pavaros valdiklio schemos. Taip pat nagrinėjamas pavaros valdymo algoritmas, pateikiamos esminės mikrovaldiklio programos dalys. Čia atliekama pavaros darbo režimų analizė, nagrinėjama mikrožingsnio svarba pavaros greičiui bei tikslumui. Modernizuotoje pavaroje naudojami moderniausi žingsninių pavarų valdymo metodai, pavaros tikslumas padidėjo 30 kartų. / This postgraduate thesis is about analysis and modernization of positioning gear, used in geodesic equipment. Old gear used in the rig is very slow and not accurate. Mission of this work is to make gear faster and more accurate. The theoretical path consists of geodesic equipment calibration methods, principles of rig operation, analysis of stepper motor dynamic characteristics. Experimental path consists of: principal and function diagrams of stepper gear driver, program algorithms, and parameters investigation of all working modes of the gear. The most modern methods is used in renewed gear, the precision increased 30 times.
9

Multisensor fusion and control strategies for low cost hybrid stepper motor solutions

Wallin, Mattias January 2017 (has links)
This thesis has explored if it is feasible to produce a good estimation of the rotational position of a stepper motor by using sensor fusion schemes to merge a sensorless position estimation (based on the back electromotive force) with the measurement from a magnetic rotational position sensor. The purpose was to find a cheaper alternative for position feedback in closed loop control from conventionally used rotational encoders and resolvers. Beyond the sensor fusion a suitable position control logic was also developed to verify the concept of a low cost closed loop hybrid stepper motor solution for high precision position applications. The sensor fusion and position control were simulated offline to first test the feasibility of the implementation, after which laboratory tests were performed to assess online performance. The extended Kalman filter implemented improved the performance of the magnetic rotational position sensor which was used exclusively at lower speeds (between 0-75 rpm) by decreasing its root-mean-square error by almost half from 0.0733 unfiltered to 0.0370 filtered (in mechanical degrees). When fusing both position signals at higher rotational speeds (75-400rpm) did the extended Kalman filter clearly improve position estimation accuracy compared to the single sources. It is not meaningful however to discuss the numeric improvement of the filter at these working points as this result is not conclusive but based on some fortunate conditions. This is because the two signals used for the fusion is diverging towards positive and negative error respectively for increasing rotational speeds making the fused estimate result in between. This basically means that the result from the fusion is outperforming two very bad signals, and is then not meaningful to use as a measure of how well the fusion is actually performing. Further work on the raw signals used for fusion need to be performed before a proper assessment on the fusion performance could be made.
10

Automatická expoziční jednotka pro výrobu DPS / Automatic exposure unit for PCB production

Blahút, Jozef January 2017 (has links)
This diploma thesis deals with the issue of fast high-quality prototype production of printed circuit boards for the needs of the mechatronics lab. Within the scope of this thesis a prototype machine was proposed and created together with control software, which by the help of DLP projector and two stage axis allows to produce printed circuit board in relatively short period of time.

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