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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.
61

Umělá aorta pro demonstraci činnosti intraaortální balonkové kontrapulzace / Artificial aorta for activity demonstration of intraaortal baloon contrapulsation

Bičiště, Jan January 2009 (has links)
This dissertation work describes design and construction of simulated aorta device intended to demonstrate performance of the intra-aortal balloon catheter (IAB), and to test reaction of the contra-pulsation pump during simulated cardiac output in conditions of tachycardia, bradycardia and arrhythmia. The major part of the device is transparent plastic tube. The pressure pulses (waves) are generated inside this plastic tube to simulate real cardiac output. These pressure pulses are generated by step motor with membrane. The step motor is controlled by programmable control system AMiNi-E. Individual pressure pulses simulate cardiac output in conditions of tachycardia, bradycardia and arrhythmia. Required simulated cardiac output is selected by control switches. Generated pressure pulses are read by pressure sensor and are transferred to the control system of the configuration computer. Read data can be displayed as graphs in program Microsoft Excel. The intra-aortal balloon catheter (IAB) is inserted inside the aorta and is connected with contra-pulsation pump which on pressure pulse is responding.
62

Číslicově řízené dvouosé polohovací zařízení pro digitální fotoaparát / Digitally-controlled dual-axis positioning rig for digital camera

Hrubý, Michal January 2011 (has links)
This thesis introduces the construction design of two-axis positioning device to be used as panoramic head. Theoretical part explains parts of the device and in the practical part is the device assembled. The result is a complete positioning device for digital camera Canon EOS 500D and for similar camera.
63

Digitální zapisovač dat / Digital data recorder

Müller, Tomáš January 2010 (has links)
This thesis deals with method of measuring optical beam intensity, searching for communication system beam using stepper motor movement of the optical head and processing measured signal for displaying on PC. The basic theory of optoelectronics is shown here concerning the problem. There is elaborated main principles of photodetector and stepper motor mainly, which are main part of device. The second part of work is theoretical design of data recorder. All parts are described individually-their characteristics and conditions for correct usage. In the last part setup of device is explained, with the references to blocks of written programs. In the last part, main funcrions of system, its hardware managing and communication are described. At the very end of thesis, examples of measured data are presented.
64

Ovládací rozhraní CNC frézky / CNC milling machine driving interface

Mitáš, Daniel January 2012 (has links)
This project deals with portal-type CNC milling machine design and construction. CNC milling machine should be able to machining light metals and alloys. This document contains description of mechanical components selection, machine frame design and building, design and construction of USB motion control unit and also contains control software description and user manual.
65

Návrh a realizace zařízení pro měření síly v tahu u SMD / Design and realization of the pull strength measuring device for SMD

Valíček, Jan January 2013 (has links)
This thesis deals with the design and implementation of a device for measuring pull strength by surface mounted devices (SMD). It analyzes the theory of pull strength testing of solder joints with emphasis on standard IEC 62137-1-3 and describes the selection of components utilized to create mechanical construction and electrical parts. These electronic parts made or innovated in this work were control system based on microcontroler Atmega164P, power circuit for stepper motor and communication of measure equipment TEST 321 with PC. The whole design is complemented by simulation of mechanical stress to the critical components using ANSYS. The conclusion summarizes the most important parameters of this equipment.
66

Tříosé ovládání tiskového stroje / 3D Printing Machine Control

Kočár, Darius January 2010 (has links)
This thesis is about creating library for control of the 3D printing machine. Printer active axes are realized by stepper motors from Microcon Corporation connected with CD30x control unit. Communication between application and control units is via RS232 serial link. Part of this work is dedicated to application showing typical usage of this library.
67

Systém pro bezkontaktní měření otoku končetiny / System for contactless ultrasonic measuring of edema

Zahradníčková, Ludmila January 2017 (has links)
Determination of the extent and state of a limb edema is based on information about its current volume. There are a number of methods for volume measurements. The theoretical part of this semestral thesis discusses the etiology, classification and principles of volume measurements and basic information about ultrasound and stepper motors. The practical part consists of a design of own device for a contactless limb volume measurement with ultrasonic module. It consists of a code for a microcontroller which controles the whole system including the computational operations and a real model of the system.
68

Design and Implementation of the SAX, a Robotic Measurement System for On-Chip Antennas at 140-325 GHz

Pontusson, Magnus January 2018 (has links)
There is currently a demand of mm‑wave on‑chip antennas to enable all kinds of new applications in several different areas. But the development requires, among other things, special equipment used during the measurement phase due to the small dimensions and the high frequencies. In this project a robotic measurement system, SAX (Single Arm eXtra), was designed and constructed at Micro and Nanosystems (MST) department at KTH Royal Institute of Technology (Sweden). The purpose of the SAX is to enable radiation pattern measurements of on‑chip antennas ( 140 GHz to 325 GHz ), whether the boresight is vertical or horizontal along with other requirements, by moving a converter with the measurement antenna around the antenna in question. Several alternative designs for the basic construction, both from other works and invented by the author, were analyzed based on the requirements for this project and other limitations. The chosen unique design, the SAX, is very compact and uses only one stepper motor. Several parts have been developed in this project to ensure the proper functionality of the SAX. That includes a main operator program, a motor input signal generating program, a motor input signal executing system, a security system, and a system for controlled rotation of the SAX. For the input signal to the motor two different algorithms to generate the time delays were developed and tested. They were adapted to make the motor manage the sweeps of an ever‑changing load with high inertia during acceleration and deceleration. One of them was developed to make the time delay array generation much more efficient albeit with larger approximation error. The SAX worked well and should be rather easy‑to‑use regarding the operation of the system, from the physical maneuvering to utilizing the sub‑systems to the running of the main operator program. It fulfilled the specific requirements by enable a cross pattern measurement from  -60° to +60°  both from above and from the side, adjustment of the radius between 15cm to 45cm , adjustment 10cm in height, to be rotated along the floor in steps of 1°, measurement steps of 1° with an accuracy of less than 0,5° (the largest error was measured to be ≤ 0,461°). However, some calibration work needs to be done before the optimal performance of the system is reached. As a verification of the operation of the system data from measurements of open‑ended waveguides was presented. / Det finns en efterfrågan på chipantenner för millimetervågor eftersom de kan möjliggöra allehanda produkter inom flera olika områden. Forskningen på dessa ställer dock bl.a. speciella krav på utrustning som används under testmätningsfasen p.g.a. de små dimensionerna och den höga frekvensen. I detta projekt har ett robotsystem, SAX (Single Arm eXtra), utformats och konstruerats på avdelningen för Mikro- och nanosystem på KTH. Syftet med SAX är att mäta högfrekventa chipantenner ( 140 GHz till 325 GHz ) genom att förflytta en frekvensomvandlare med tillhörande mätantenn i en cirkulär bana runt antennen ifråga, oavsett om den är riktad vertikalt eller horisontellt och givet andra kravspecifikationer. Flera designalternativ för den grundläggande konstruktionen, både från andras arbeten och framtagna av författaren själv, har analyserats utifrån kravspecifikation för detta projekt och andra begränsningar. Den valda unika designen, SAX, är väldigt kompakt och använder sig bara av en stegmotor. För att möjliggöra funktionen i den slutgiltiga produkten har flera delar tagits fram vilka inkluderar ett operatörsprogram, ett program för genererandet av motorstyrsignaler, ett program för motorstyrning, ett säkerhetssystem och ett rotationssystem för kontrollerad rotation av SAX. För genererandet av motorstyrsignaler i form av tidsfördröjda pulser framtogs två olika algoritmer. De ger anpassade accelerations- och retardationssignaler för att motorn ska klara av att förflytta en föränderlig last med stor tröghet. En av dessa framtogs med syfte att mycket effektivt generera pulstiderna om än med större approximationsfel. SAX fungerade tillfredsställande och torde vara ganska lättanvänd med tanke på vad systemet kräver av operatören, från att fysiskt manövrera systemet till att använda delsystemen till att använda operatörsprogrammet. Systemet uppfyllde de givna specifika kraven genom att möjliggöra mätningar i form av ett kryssmönster från -60° till +60°  både ovanifrån och från sidan, radiejustering från 15cm till 45cm , höjdjustering över 10cm , rotation över golvet i steg om 1° , mätningar i steg om 1° med en noggrannhet på 0,5° (den största avvikelsen uppmättes till ≤ 0,461°). Vidare kalibrering behöver dock utföras för att utnyttja den fulla potentialen hos konstruktionen. För att verifiera funktionsdugligheten för systemet presenterades data från mätningar gjorda på öppna vågledare.
69

Testautomatisering av linjärmotorer / Test automation of linear motors

Gidlöf Örnerfors, Linus January 2017 (has links)
Detta examensarbete har utförts på uppdrag av Stegia AB. Stegias linjärmotorerprovas i en testbänk innan motorerna skickas till den slutliga kunden. Idag finns ettbehov av en testbänk som skall samla in data från utförda tester, minska risken atttesterna utförs fel, samt att testbänken skall vara lättare att använda för produktionspersonalen.Idag innehåller linjärmotortestet många manuella arbetsmoment,vilket innebär en hög risk för felaktiga resultat utan möjlighet till spårbarhet i testresultatet.Målet med detta arbete är att förenkla det slutliga testet av linjärmotorerför produktionspersonal, samt att minska risken för felaktigt utförda tester genomtestautomatisering. Resultatet presenteras i form av en prototyp som har konstruerats,vars syfte är att förbättra test av linjärmotorerna genom att uppfylla målet atträtt utförda tester görs på motorerna. Resultatet säkerställs genom validering ochutvärdering och analys av den framtagna prototypen. / This diploma work has been carried out on behalf of Stegia AB. Stegia manufacturesand sells linear motors that are tested in a test bench before shipped to thecustomer. Today there is a need for a test bench that collects test results from theperformed tests. The company would like to lower the risk of falsely made tests,and to make the test bench easier for the production staff to use. At this moment,the test of the linear motors is made up of several manual tasks before the test iscompleted. This increases the risk of wrong results because of incorrectly madetests, with no traceability of the results. The goal with this diploma work is to lowerthe risk of incorrect test result by automating the testing process for the productionstaff. The result is presented as a prototype, that should increase the reliability ofthe test result of the motors. The result is then validated and analyzed in this report.
70

Malý CNC stroj / Small CNC machine

Moštěk, Jiří January 2014 (has links)
This diploma thesis deals with the design and construction of a three-axis CNC machine primarily designed for PCB drilling and production of front panels for various electronic devices. All three axes are driven by stepper motors NEMA 23 which are connected to stepper motor drivers L6470. Processor STM32F407 is used to control the whole machine. The wiring is completed by a LCD display with touchscreen which is used to communicate with user. Data for drilling can be entering manually or via USB inerface. Part of this thesis is the selection of a suitable construction and components, assembling equipment, wiring design of electronic circuits and writing the code to control the machine. Finally, the parameters of the designed device have been measured.

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