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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.
21

GPIB- kommunikation och PID reglering med LabVIEW

Abbas, Azhar January 2009 (has links)
LabVIEW ger en snabb och enkel tillgång till att styra instrument och en mycket stor databas med drivrutiner för DAQ-kort och olika datorgränssnitt (GPIB, serie, osv.). Många instrument och datorer kan anslutas till GPIB-bussen.  Detta kan ge en praktisk modell för utveckling av instrumentets styrprogram i LabVIEW med hjälp av GPIB-gränssnittet. Ett program i LabVIEW 8.2 med hjälp av GPIB-bussen kan kopplas till t.ex. multimetern (HP-34401A) för att mäta och visa multimeters noggrannhet. Men på grund av fel i drivrutiner för GPIB-gränssnittet kunde jag inte köra programmet med GPIB-bussen. Genom att använda LabVIEW 8.2 med hjälp av DAQ-kort kan en PID-regleringsalgoritm simuleras. PID konstrueras med virtuella instrument som innehåller alla nödvändiga komponenter och utrustning som krävs för att reglera någon linjär eller olinjär process exempelvis att nivåreglera två tankar i serie. Här stöter vi på alla de grundläggande regulatorer och får möjlighet att bygga PID med LabVIEW på ett enkelt sätt. Det finns två metoder för att bygga PID. Den första är med matematiska funktioner och den andra är med ’’Simulations functions control’’. Arbetet visar att bägge metoderna fungerar bra för att lösa uppgiften jämfört med färdiga PID-controls på LabVIEW.
22

Development of a flexible test platform utilizing gearbox simulators through programming

Unibaso Eguzkitza, Beñat, Ismail Dobón, Ismael January 2016 (has links)
A gearbox simulator is developed as platform for testing and demonstrating purposes. For that, a rig composed by a mechanical system and electronic equipment for controlling two servomotors is used. The objective of this equipment is to simulate the forces that the gearbox would transmit to the gear lever when the gear change operation is being carried-out. To reach this goal, a program is developed in LabVIEW to command the servomotors, emulating the forces by controlling the output torque and transmitting them to the gear stick as it would be in a real gearbox, taking into account real force-angle curves. Also, a graphical user interface is developed in order to monitor the simulator performance ad ease the way the data is chosen and introduced into the software.As seen in the experiment results, the graphs present similarities in shape and magnitude, which is important in regards of feeling; a better performance could be reach suppressing some system constraints.
23

Development of Autonomous Shallow Water Acoustic Logger

Yen, Chia-You 27 July 2003 (has links)
The sonobuoy originated from military submarine detection¡Ait was also used to measure ocean acoustic signal by scientists¡Abut the continuous recording and transmitting design by early sonobuoy is not suitable for long-term or scheduled observations. In this research¡A¡§off the self¡¨ components were integrated to develop an autonomous sonobuoy¡Awhich can be used to measure shipping noise and marine life acoustic signal in coastal water. The electronic design is based on a PC motherboard¡Ait is currently configured with a maximum sampling rate of 44.1 kHz¡Aand a maximum storage capacity of 40 GB. The sound was collected by a plug and play hydrophone system¡Awhich is controlled by a program written by LabVIEW. In addition to the programmable data acquisition and low cost advantages¡Athe flexible design allows quick system expansion and adjustment¡Ait can also be configured to record from multiple transducers.
24

Design av effektelektronikkort till NI ELVIS II

Kim, Persson January 2015 (has links)
Det här arbetet handlar om designa ett effektelektronikkort till National Instruments utvecklingsplattform ELVIS II, som skakunna styras från programmet LabVIEW. Kortet är tänkt att kunna användas i kurser inom effektelektronik på högskolenivåoch har designats för att passa ELVIS II's hårdvaruspecifikationer. I arbetet har alla kretsar byggts upp och simulerats iMultisim. Kretsarna som designats är en step-up-konverterare, en step-down-konverterare, en likriktare, en växelriktare ochen variabel last. Simuleringarna visade att kretsarna fungerar som tänkt och vad som skiljer sig från det teoretiska. Någotsom ofta visade sig i simuleringarna var att strömförbrukningen under korta perioder kraftigt kan överstiga det ELVIS II kanleverera, vilket behöver undersökas närmare. Rapporten innehåller scheman och simuleringsresultat från alla kretsar, vadsom är kvar att lösa på dessa och hur dessa kan anslutas till ELVIS II.
25

Analyzátor UHF RFID komunikace založený na SDR / SDR-based UHF RFID communication analyzer

Vychodil, Josef January 2013 (has links)
Main topic of this thesis is development of software for capture and analysis of RFID communication in UHF band (standard EPC Class-1 Generation-2). One part of the work is focused on the basics of the RFID systems, software defined radio concept and graphical programming language LabVIEW. Main part of this thesis is discussing the developed software itself, its methods and principles. Next part is dedicated to present the graphical user interface of created application and its functionality. Last part of this thesis contains examples of captured and analysed processes in UHF RFID communication.
26

Optimization of the Process for Semiconductor Device Fabrication in the MicrON 636 Whittemore Cleanroom Facility

Gray, David T. 19 February 2004 (has links)
The main objective of this work is to develop and optimize a process for the fabrication of basic semiconductor devices in silicon using the Modu-lab toolset in the MicrON 636 Whittemore cleanroom facility. This toolset is designed to work with four-inch silicon wafers, in a class 10000 cleanroom. Early work on this process produced functioning devices, with low yield and little to no process control. Three aspects of the process were therefore selected for optimization in this work. The oxidation of the surface of the silicon wafers could not be made to follow models proposed by and accepted in the literature. By carefully changing the airflow in the oxidation furnace module, the uniformity of the oxide layer and the agreement of the growth with models increases to acceptable levels. Also, the effects of redistribution of dopant species due to growth of the oxide layer and the subsequent thermal processing are examined qualitatively. Phosphorus diffusion in single-crystal silicon has a complex diffusion mechanism involving charged-vacancies, with concentration-dependent diffusion coefficients. It is therefore a complex mathematical problem to model the diffusion of phosphorus from a solid source within the crystal. An empirical model is proposed that accurately predicts the junction depth and sheet resistance of diffused phosphorus layers within the silicon wafer. Throughout the course of the process it is necessary to monitor the characteristics of the wafers to assure proper conditions. A semiconductor parameter analyzer has been created for this purpose. Our system uses a Keithley model 2400 source meter, Signatone probe station and four-point probe stage, and a PC to measure DC I-V electrical characteristics of materials and devices. The measurements of sheet resistance, as well as device characterization of resistors, p-n junction diodes, and nMOSFETs provides feedback about the accuracy of processing steps, as well as a pedagogical tool for illustrating semiconductor device physics and operation. / Master of Science
27

Návrh systému pro sběr provozních dat obráběcího stroje / Design of DAQ system for production machine

Sláma, Eduard January 2018 (has links)
The aim of the diploma thesis is to make functional application for design of DAQ system for productive machine by using LabVIEW and platforms cRIO. The first part is focused on productive machine. After the thesis continues with specific examples. These examples have impact on machining accuracy and their measurements. The second part of diploma thesis is focused on making measurement program. LabVIEW FPGA Module, LabVIEW Real-Time Module are used in the program.
28

Integrating experimentation and instrumentation in upper-division physics

Zhang, Qi January 1900 (has links)
Master of Science / Department of Physics / Nobel S. Rebello / Over the past 20 years there have been limited efforts to improve students’ interest and knowledge of electronics and to offer students experiences to integrate and apply their knowledge of electronics with experimental physics. None of the reform efforts cited in the literature have performed a careful assessment of student learning and attitudes, and most of them report anecdotal success. These programs share several commonalities. They typically have a capstone project experience in which students apply their knowledge and skills in electronics and instrumentation to a particular context. The KSU Physics Department has embarked on an endeavor to improve the PMI (Physical Measurement and Instrumentation) class taken by physics majors. Capstone project experiences for students in PMI will provide them with an opportunity to revisit experiments they completed in previous courses. They then apply the knowledge and skills in electronics and instrumentation learned at the beginning of the PMI course to automate these experiments. The use of LabVIEW and NI ELVIS provides a range of opportunities to students due to their visual interface and easy learning curve. However, they do have some disadvantages such as speed and resolution when compared to more traditional measurements with oscilloscopes. Three specific capstone experiences have been developed in PMI. These include saturated absorption in Rubidium, the Franck-Hertz experiment, and the speed of light measurement. In each case, students first complete the traditional experiments and then use NI ELVIS and LabVIEW to automate these experiments. Students are provided minimal explicit guidance in completing the capstone projects. These include one-page handouts describing the goals, basic procedures and questions that students have to answer for themselves. Comparing data from traditional experiments and those from automated using LabVIEW and NI ELVIS provides a context in which to discuss the trade-offs between the traditional and automated experiments. Future efforts include the development of more experiments as well as careful assessment of student learning and attitudes as a result of the capstone experiences in the PMI class. This project can potentially inform similar efforts at other institutions in the future.
29

LabVIEW application with embedded Lua scripting for a laser based measuring machine

Coetzee, A., Van Niekerk, T.I. January 2013 (has links)
Published Article / This paper presents the work on the development of software for an industrial laser based measuring machine. The goal being not only for a working application, but also to optimise the development process and ease future maintenance of the software. LabVIEW with its graphical method of programming allows engineers to easily create large software applications to control industrial processes and machines. This software if not properly designed can lead to stability and maintenance problems. The experience gained from developing, maintaining and improving a LabVIEW application for a laser measuring machine, results in the integration of the Lua scripting language into LabVIEW. It is shown how the embedded Lua allows the LabVIEW software application for the machine to be structured for simpler development and maintenance.
30

Beräkning av massa genom mätning av hydraultryck

Lynghed, Christoffer, Andersson, Viktor January 2009 (has links)
Vår uppgift var att ta fram en algoritm för hur lastens massa förhåller sig till hydraultrycket i ett hydraulsystem för en truck. Algoritmen skulle sedan implementeras i en vågprototyp. Lösningen skulle vara kostnadseffektiv. För att undersöka sambandet utfördes mätserier där vi provade olika komponenter. Resultatet av mätserierna analyserades och vi fann ett samband mellan massan och hydraultrycket. Med hjälp av sambandet kunde sedan programkod för en vågprototyp skrivas tillsammans med tillhörande funktioner. Resultatet blev en fungerande vågprototyp för trucken som användes. Denna prototyp behöver dock testas och utvärderas ytterligare på fler truckar innan en eventuell slutprodukt kan bli aktuell. / Our task was to develop an algorithm for the relationship between mass and hydraulic pressure in a hydraulic system in a forklift. The algorithm was then to be implemented in a prototype of a forklift scale. The solution had to be cost-effective. To examine the relationship we performed series of measurements in which various components were tested. The results of the measurements were analyzed and we found a correlation between mass and hydraulic pressure. Due to this we could write a code for a forklift scale prototype with features. The forklift scale prototype worked on the forklift that we used but it needs to be tested and evaluated further in more forklifts before a final product can be made.

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