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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.
31

Automation of refilling station in clean room

Sollie, Vincent, Malmström, Johannes January 2019 (has links)
This thesis aims to confirm a proof of concept on how to get a robot to pick up a plastic bag containing 3500 plastic caps, cut it open and pour the content, all within a restricted Clean room. The work was executed in an agile way with several ongoing iterative processes in parallel. In the present production line, refilling caps are done manually. For those working in the production line, this task entails heavy lifting and the concern of keeping an eye out for when to refill and how many caps there are in the production line all the time. The result is a working prototype of a robot tool, consisting of a combined clamp and vaccum bag gripper and a self standing linear unit with a blade mounted to it. When tested, this proved to be a functioning solution to the task in hand. The gripper is designed to be mounted on a six axis industrial robot and the blade is placed inside a robot cell. Simulations show that the task is easily done fast enough to supply 5 production lines, producing in full speed,with caps. Solely this unit will not contribute much to a production line if implemented in a factory, since it does not take material flow into consideration. It can merely be seen as a part of a bigger automation chain.
32

Savonius wind turbine innovation integrated in a constructed nano grid system

Andersson, Oskar January 2019 (has links)
A nanogrid system for supplying neutrino detectors on Antarctica with electricity is designed and built. The nanogrid system could later on be implemented in various configurations where suppling electricity to neutrino detectors is one area of use. The energy system that is acting on site in Antarctica is based around solar panels to provide power to the measuring equipment. However, providing electricity in such a way is not optimal due to its failure in delivering electricity at times. A nanogrid that can stand the demands of constant energy supply to the measurement station are therefore constructed. The energy sources that are integrated into the nanogrid are an innovation in vertical axis wind turbine and photovoltaics. The wind turbine innovation is tested under real conditions for the first time. In the constructed nanogrid, there are also integrated energy storage consisting of battery cells that are coupled together to a coherent unit. Measurement equipment is also implemented for analyzation of acting wind turbine as well as different types of safety equipment for redundancy in the system. In the nanogrid, a rectifier for AC to DC transformation is constructed. An inverter for DC to AC transformation is also implemented for supplying electricity to the equipment that are acting on the grid. The system is tested under real conditions. The whole system could observe partially function and configurated well to the various parts of the whole system. Further optimisation of some parts of the system from the prototype is needed.
33

Internet of things and implementation of local wireless sensor network

Jonsson, Anthon January 2019 (has links)
This master’s thesis covers the research and development of a local wireless sensor network with capabilities for IoT (internet of things) applications and with the ability to monitor and automatically control a watering system with soil humidity as input. The goal with this thesis was to develop a system where the wireless communication within the local network is suited for low power and lossy networks (LLN). The system was to be controlled and monitored from a user interface which is available from the internet. A system was developed with a wireless network with a suited underlying network stack with protocols that was fitted for the constrained environment. The nodes send values to a website with a UI (user interface) where values can be monitored and the user can control the system and send values to specific nodes within the system. The sensor nodes communicate with protocols developed for low power networks and an edge router was built for the purpose of routing this network to the internet. Research in the internet protocol suite has come a long way and a large variety of protocols has been developed to fit almost every set of nodes with different battery lifetime, processing power, and memory size. This thesis shows that the communication stack can be modelled with suited protocols to be satisfactory for different internet of things applications with high energy efficiency.
34

Projektering av lokalnät med fördjupning i selektivitet

Ebers, Lucas, Eriksson, Niklas January 2019 (has links)
In power system, when a local network with over head lines is replaced by a network laid underground, itchanges the characteristics of the material used and gives an opportunity for an updated sizing. The goal withthe project was to present a proposal of a reconstruction of a old local network to a modern local network andpresent a selective coordination plan for all the branches in the new network. The methods that are used isthe Velanders method for interleaver of the maximum power, sizing according to “SvenskStandard”(Swedish Standards) and curve fit of trip curves to present digital produced selective coordinationplan. The new underground local network delivers a better electrical quality, that fulfills the triggerconditions and obtains a good selective coordination. / Inom elkraftsystem, när ett luftburet lokalnät ersätts med ett markförlagt förändras förutsättningarna i formav materialets egenskaper och det ger möjlighet för uppdaterad dimensionering. Målet var att presentera ettförslag på ombyggnation av ett äldre luftburet till ett modernare markförlagt lokalnät och presenteraselektivplaner för samtliga grenar av det nya nätet. Metoder som använts är Velanders metod försammanlagring av maxeffekter, dimensionering enligt Svensk Standard och kurvanpassning avutlösningskurvor för att presentera digitalt framställda selektivplaner. Det markförlagda lokalnätet levereraren bättre elkvalitet, uppfyller utlösningsvillkoret och erhåller god selektivitet.
35

Power Supply to Mobile Device

Kirby, Brenden January 2019 (has links)
While technology develops, many devices are becoming portable and battery driven. These devices are among us and are unconditionally a part of today’s society. The usage and the surrounding environment of these devices can vary depending on the intended functionality and purpose. Varying environmental conditions impact the devices charging method. This report covers the development and implementation of a printed circuit board. The circuit board is going to be used as a prototype for future testing for a portable device which the company VectorizeMove [1] is developing. The circuit board contains multiple charging methods and a voltage regulation system. The charging methods include inductive charging and micro USB charging. The charging systems are designed for a lithium polymer battery which are charged through different phases which prevent damage to the battery. The voltage regulation system is implemented to test and ensure a stable voltage output for the components included in the company's device. / Medan teknik utvecklas blir många bärbara enheter batteridriven. Dessa enheter är bland oss och är ovillkorligen en del av dagens samhälle. Användningen och omgivningen av dessa enheter kan variera beroende på avsedd funktionalitet och syfte. Varierande miljöförhållanden kan påverkar laddningsmetoden för dessa enheter. Denna rapport omfattar utveckling och genomförande av ett kretskort. Kretskortet kommer att användas som prototyp för framtida testning för en bärbar enhet som företaget VectorizeMove [1] utvecklar. Kretskortet innehåller flera laddningsmetoder och ett spänningsregleringssystem. Laddningsmetoderna inkluderar induktiv laddning och micro USBladdning. Laddningssystemen är konstruerade för ett litium polymer batteri som laddas genom olika faser som förhindrar skador på batteriet. Spänningsregleringssystemet implementeras för att testa och säkerställa en stabil spänningsutgång för komponenterna som ingår i företagets enhet.
36

SOLENERGI FÖR JORDBRUKSNÄRINGAR : Ekonomiska förutsättningar för jordbruksnäringar för installation av solcellsanläggningar

Jansson, Hampus January 2019 (has links)
The purpose of this project is to analyze the economic parameters that affects the profits from a roof mounted solar cell installation for an agriculture company in Sweden. To analyze the different production type and the impact of the fraction self- used electricity is calculated with respect to the direction of the installation. The parameters that are affecting the profit are the yearly electricity production, the investment cost, the fraction self-used, the price of bought and sold electricity and any subsidies. The conclusion is that the type of production does not affect the self use as much and an installation facing south still have a higher self use due to the higher total electricity production. The most important factor for profit is the subsides, without subsidies the investment does not give a positive yield rate. In second place comes the orientation and the total investment cost. Two of the three companies studied would get 1-3% inflation compensated interest rate with 20% subsidies and the third, relatively located far up north, reached 1-2% inflation compensated interest rate with the same subsides. The lower interest rate comes from the lower yearly electricity production. Another 2 percentage interest rate can be added if the subsides of 40% is granted for all three of the studied companies. As complement to the already existent feeder cable a solar plant combined with a battery storage can support a new house on the property during summer. As a backup for a power outage, a solar plant and a battery costs more and does less than a tractor driven electric generator.
37

Värmeåtervinning - styrning för frånluftsvärmepump i flerbostadshus

Ali, Rony January 2019 (has links)
No description available.
38

Design och tillverkning av universell förstärkarmodul för trådtöjningsgivare

Hassanzadeh, Rahman January 2006 (has links)
Som examensarbete har jag fått den spännande uppgiften att ta fram en universell förstärkarmodul för trådtöjningsgivare för användning med kvart-, halv- och helbrygga (Wheatstonebrygga). Uppgiften ska utföras åt ett företag som kommer att använda kretskortet för mätningar i industrimiljö. Det här kortet är tänkt att uppfylla många olika behov, där det viktigaste är kraftmätning på ett objekt. Det här görs med hjälp av en Wheatstonebrygga, eftersom spänning är direkt proportionell mot resistans som i sin tur är proportionell mot kraften, vilket betyder att en ändring i resistansen ökar eller minskar spänningen. Modulen ska känna av minsta möjliga resistansändring för att registrera belastningen på bryggan. Syftet med att använda kvarts-, halv- eller fullbrygga följer senare i rapporten. Mätningsspänningen till hela modulen är +15 och -15 volt. Vid nollbalansering av bryggan är det viktigt att modulen inte ger ut en signal på grund av temperaturdrift eller obalans i mätobjektet. För att uppnå detta mål fick jag använda:  En mikroprocessor (ATmega 16) som har inbyggd A/D –omvandlare.  En D/A –omvandlare på 10 bitar. Vid mätning på stora avstånd avsåg jag att göra avläsningar på ström istället för spänning. Till skillnad från spänning som avtar ju längre ledningen är, bevaras strömstyrkan hela vägen. Att beräkna spänningen när resistansen och strömmen är givna, är enkelt. Konstruktionen gjordes delvis i programmet Multisim och kretskortet tillverkades med hjälp av programmet Ultiboard.Resultatet av projektet var att ett mönsterkort tillverkades enligt företagets kravspecifikation samt att komponenterna monterades. / The degree project assigned to me was to build a universal amplifier module for a strain gauge that could be used in 3 different states ie. quarter, half or full wheatstone bridge. The printed circuit card to be built for a company shall fulfil many needs and it is intended for industrial purposes. The most important is measuring the force on an object. This is accomplished with the help of a wheatstone bridge since voltage is directly proportional to resistance and furthermore resistance is proportional to force. This means that a change in resistance results in an increment or decrement of voltage. The important factor in this module is that it should register the least possible change in resistance so that a value gets recorded in the bridge. The reasons for using quarter, half or full bridge are explained later in the report. Measurement voltage for the module is +15 and -15 volts. The module should not give out a signal because of temp drift or imbalance of the object in measure at the point of zero balancing it. To attain this goal, I used:  A microprocessor (ATmega 16) that has a built-in A/D converter.  A D/A converter of 10 bits. In long distance measurements, the idea of monitoring current instead of voltage sounded better. This is because current remains the same along the line(wire) whereas voltage subsides the longer the wire. Calculation of voltage when resistance and current are given is pretty simple. The construction was partly done with the help of the program Multisim while the printed circuit card was manufactured with the help of Ultiboard. The result was a complete card with components mounted and constructed according to the company’s demands and specifications.
39

KONCEPTANALYS OCH DRIFTFALLSOPTIMERING AV "FREEPOWER – SOLAR BOAT" / CONCEPT ANALYSIS AND OPERATION CASE OPTIMIZATION OF "FREEPOWER - SOLAR BOAT"

Ahlbäck, David January 2019 (has links)
This report aims to analyse the concept of Bjurtech AB:s ongoing development project “Freepower - Solar Boat”. Main focuses are technical optimization and usability from an end user perspective. Bjurtechs idea is to build an electric-powered 5-meter boat charged by integrated photovoltaic cells. The project´s intended pilot market is Sri Lankas coastal fishing fleet. A version for the Scandinavian market is also under consideration and both concepts are analysed in this report. Initially a 4.5-meter prototype was built and tested to try the concept in practise. Methods used are computer simulations in Matlab based on data collected from trail runs with the prototype combined with weather data from Sri Lanka and Sweden. The data and simulations were then used to try to determine whether the concept works for the intended target markets, as well as how the assumed user profiles affect usability and technical deterioration such as battery life. The approach used was to try to determine how to maximize the availability of the system in regards to battery charge level over the whole year at the same time as maximizing distance and boat speed per day. The systems CO2 emissions were then compared to an equivalent petrol-powered boat with the same amount of running hours over 25 years. The main findings of the study are, provided 12 to 14.5 nautical miles is regarded as a sufficient daily distance at 3 to 3.7 knots boat speed, that the system can deliver a high level of availability all year around for fishing operations in Sri Lanka. Considering the demand for daily availability is not as high for the assumed recreational use in Scandinavian markets the system is deemed to perform at a satisfactory level at these latitudes as well. The CO2 comparison showed a significant emissions decrease in the case of year around operations in Sri Lanka. In Scandinavia a reduction is obtained if there are a sufficient amount of operating hours per year. An increase of the installed rated power, Wp, was found to be the most cost efficient way of improving overall performance and that the prototypes photovoltaics of 580 Wp should in both the Sri Lankan and Scandinavian case be increased to a minimum of 800 Wp. Finally it was concluded that user awareness of how system operation impacts battery life can be of significant importance for a positive environmental result and long technical lifetime.
40

Identification of machine tools´ locations

Águila Rodríguez, Guillermo, del Álamo Alcalde, Adrián January 2019 (has links)
The scope of this thesis will be focused on the machine FORMA Z1 which is one ofthe most functional amongst the sort of machines currently available in the market. Itprovides faster tool changes besides a huge variety of tool layouts with the possibility ofmaking a product with one only set up. Furthermore, the combi-beam rotation capability,together with dual sets of tools, give to the machine an exceptional competence.Through this project, some of the shortcomings in the usability of the machine are evaluatedto be able to give an accurate solution to provide it of extra functionalities, thusacquiring better efficiency during the performance. This solution consists of the developmentof a device which will aid the operator during the tool arrangement of the machine.The solution includes a platform with a laser that will point out where the operator mustplace the corresponding tool. The system will know where to locate it because the realmachine would generate an XML file which would contain all necessary data. All thisdata will be read by a computer and send it to the microcontroller that will control allthe system.The solution proposed improves the throughput and reduces the time needed in the bendingprocess increasing the facility in the process of bending metal sheet. However, thereare some disadvantages on the implementation of this device. The new machine wouldbe more expensive and the software would be changed to include the new system and theprogram that reads the XML document.

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