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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

Trådlös kamerastyrning

Karlsson, Petter, Lundquist, Rickard January 2008 (has links)
<p>As an amateur it can be difficult filming from several angles at the same time as this requires several cameras. It´s also hard to film at occasions when it´s not appropriate to manoeuvre the camera manually. Systems for solving these problems already exist, but it´s either more expensive, professional</p><p>systems or cheaper systems with limited functionality.</p><p>The purpose of this project is to develop a cost efficient solution to the problem above that offers a better functionality then existing commercial systems. The biggest difference from existing products is the wireless video feedback from the camera to the remote unit.</p><p>The result of the project is a system consisting of two units, a manoeuvre unit with a cradle for the video camera and a remote unit from which the operator can control pan and tilt of the video camera.</p><p>Communication between the two units is wireless.</p><p>On the remote unit there is a joystick and a display mounted. In addition to this, there is also an IR receiver that is capable of reading the signal from the cameras own remote and sending it to the manoeuvre unit.</p><p>The manoeuvre unit is equipped with one motor to control the tilt function and one motor to control the pan. There is also a connector for an IR LED to control the video cameras functions. The casing</p><p>for the manoeuvre unit is made of a plastic material through a process known as SLS, selective laser sintering. The cradle that the video camera is attached to is designed to rotate around the center axises</p><p>of the camera in order to develop a minimal torque.</p>
2

Trådlös kamerastyrning

Karlsson, Petter, Lundquist, Rickard January 2008 (has links)
As an amateur it can be difficult filming from several angles at the same time as this requires several cameras. It´s also hard to film at occasions when it´s not appropriate to manoeuvre the camera manually. Systems for solving these problems already exist, but it´s either more expensive, professional systems or cheaper systems with limited functionality. The purpose of this project is to develop a cost efficient solution to the problem above that offers a better functionality then existing commercial systems. The biggest difference from existing products is the wireless video feedback from the camera to the remote unit. The result of the project is a system consisting of two units, a manoeuvre unit with a cradle for the video camera and a remote unit from which the operator can control pan and tilt of the video camera. Communication between the two units is wireless. On the remote unit there is a joystick and a display mounted. In addition to this, there is also an IR receiver that is capable of reading the signal from the cameras own remote and sending it to the manoeuvre unit. The manoeuvre unit is equipped with one motor to control the tilt function and one motor to control the pan. There is also a connector for an IR LED to control the video cameras functions. The casing for the manoeuvre unit is made of a plastic material through a process known as SLS, selective laser sintering. The cradle that the video camera is attached to is designed to rotate around the center axises of the camera in order to develop a minimal torque.
3

Åtgärder för att eliminera/minimera lagerströmmar vid elmotordrifter samt mätningar av dessa strömmar vid SCA Hygiene Products-Edet Bruk

Hvalgren, Jan January 2002 (has links)
No description available.
4

Åtgärder för att eliminera/minimera lagerströmmar vid elmotordrifter samt mätningar av dessa strömmar vid SCA Hygiene Products-Edet Bruk

Hvalgren, Jan January 2002 (has links)
No description available.
5

Thermomechanical stress analysis of the main insulation system of traction electrical machines

Ismail, Dahman, Andrei, Alexis January 2020 (has links)
More efficiency heavy-duty vehicles are developed with higher range, updated electronic and mechanical parts. The fuel efficiency and pollution of carbon dioxide need to be lower to achieve new EU regulations. The global population increases with an increased number of heavy-duty vehicles. This, in turn, increases the emission. By taking the electrical and mechanical parts to the next step, the global emission problems can be massively reduced. Electrical machines are the next step towards a cleaner future. The main goal of this study to investigate the electrical machine’s insulation system. Thermo-mechanical stresses due to thermal cycling affect the electrical machines and its sub-components. By using a FEM application with simplified models of the electrical machine, results are obtained and discussed. Specifically, if 2D-models are sufficient enough to represent a 3D-model. How good different 2D-models can represent the 3D-model is compared and discussed in this study. A physical experimental analysis is done to verify and calibrate the FE-models. Which one of the less frequent higher amplitude or more frequent, lower amplitude thermal cycling affects the insulation system most is determined. The simulations could be done with either, coupled-temperature displacement analysis or sequentially coupled analysis. Coupled-temperature displacement is the fastest method to use in the simulation models. A 3D-model is the best way to describe an object and is therefore implemented. Two additional 2D-models are developed for faster computation and to investigate if the models can represent the three-dimensional geometry. All the models have specific boundary conditions to make the models more simplified. Sensitivity studies have been done to determine which parameter affects the induced thermo-mechanical stresses the most. A physical experimental setup is also implemented to validate and calibrate the simulation model. The result of the 3D-model is most accurate when simulating a three-dimensional object. Simulation results have shown that epoxy, one of the main components in the insulation system, is most critical in terms of reaching breakdown first, followed by paper insulation and copper coating. This is a typical result of all three simulation models. Whereas it is concluded that some 2D-models can present the 3D-model, others can’t. The dependent factor is the different cross-section of the electrical machine. The physical experiment shows similar results between simulation in terms of strain at a lower temperature, and the deviation gets larger as the temperature increases. The 3D-model is the model that has the best representation of a real electrical machine as it accounts for all the normal and shear stress components in all directions, but also because it has better boundary conditions compared to the 2D-models. The 2D-model in XY-plane has shown similar results to the 3D-model. One of the main insulation system components, epoxy, is exposed to the highest stresses compared to its yield and ultimate strength, followed by the paper insulation and copper coating. The sensitivity study has concluded that the axial length of the stator does not affect the stress amplitudes. The most critical parameter that affects the thermo-mechanical stresses is the temperature amplitude, the materials CTE and the thickness of the jointed layer. All maximum stress amplitudes of all the components are located at the free end. / Mer effektiva tunga fordon utvecklas med högre räckvidd, uppdaterade elektroniska och mekaniska delar. Bränsleeffektiviteten och föroreningen av koldioxid måste vara lägre för att uppnå nya EU-förordningar. Antalet tunga fordon ökar i takt med att den globala befolkningen ökar, detta leder i sin tur till ökad utsläpp av bland annat koldioxid. Genom att ta de elektriska och mekaniska delarna till nästa steg kan de globala utsläppsproblemen minskas massivt. Elektriska maskiner för framdrivning är nästa steg mot en renare framtid. Studiens huvudmål för att undersöka den elektriska maskinens isoleringssystem. Termomekaniska påfrestningar på grund av termisk cykling påverkar de elektriska maskinerna och dess delkomponenter. Genom att använda en FEM-applikation med förenklade modeller av den elektriska maskinen erhålls och diskuteras resultat. Specifikt om 2D-modeller är tillräckliga för att representera en 3D-modell. Hur tillräckligt de olika 2D-modeller kan representera 3D-modellen jämförs och diskuteras i denna studie. Ett fysiskt experiment utförs för att validera och kalibrera FEA-modellerna. Vilken av de mindre frekventa cykler med högre amplitud eller mer frekventa cyckler med lägre amplitud påverkar isoleringssystemet mest har undersökts. Simuleringarna kan göras med antingen, temperatur kopplad förskjutnings analys eller sekventiellt kopplad analys. Temperatur kopplad kopplad förskjutning är den snabbaste metoden att använda i simuleringsmodellerna. En 3D-modell är det bästa sättet att beskriva ett objekt och har därför implementerats. Ytterligare två, 2Dmodeller är framtagna i FEM-miljö för snabbare beräkning och för att undersöka om 2D-modellerna kan representera den tredimensionella geometrin. Samtliga tre modeller har specifika randvillkor för att förenkla modellerna. Känslighetsstudier görs för att bestämma vilken parameter som påverkar de inducerade termomekaniska spänningarna mest. Ett fysiskt experiment har utförsts för att validera och kalibrera simuleringsmodellerna. Resultatet visar att 3D-modellen representerar ett tre dimensonellt objekt bäst. Simuleringsresultat har visat att epoxy, som är en av huvudkomponenterna i isoleringssystemet, är mest kritisk när det gäller att först nå brott- och sträckgräns, följt av pappersisolering och koppar beläggningen. Detta är ett typiskt resultat av alla tre simuleringsmodeller. Slutsatsen visar att vissa 2D-modeller kan presentera 3D-modellen, andra kan inte. Den beroende faktorn beror på ur vilket tvärsnitt man tittar på den elektriska maskinen. Det fysiska experimentet visar liknande resultat jämfört med simuleringen när det gäller belastning vid en lägre temperatur, och avvikelsen blir större när temperaturen ökar. 3D-modellen, är den modell som har den bästa representationen av en riktig elektrisk maskin eftersom den inkluderar normal- och skjuvspänningskomponenter i alla riktningar. Anledningen är att den har bättre randvillkor jämfört med 2Dmodellerna. 2D-modellen i XY-planet har visat liknande resultat som 3D-modellen. En av huvudkomponenterna i isoleringssystemet, epoxy, utsätts för de högsta spänningarna jämfört med dess sträck- och den brottgräns, följt av pappersisolering och koppar beläggning. Känslighetsstudien har kommit fram till att statorns axiella längd inte påverkar spänningsamplituderna. Den mest kritiska parametern som påverkar de termomekaniska spänningarna är temperatur amplituden, materialens CTE och tjockleken på det skarvade skiktet. Alla maximala spänningsamplituder för samtliga tre komponenter är belägna i den fria änden.

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