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Vlivy výrobních tolerancí permanentních magnetů na synchronní motory s permanentními magnety / Effect of Manufacturing Variations of Permanent Magnets in Surface-Mounted Permanent Magnet MotorsVícha, Adam January 2016 (has links)
Master’s thesis summs up issues of mounting pemanent magnets on rotor surface of permanent magnet synchronous machine. Literature reseach is divided in two parts. First one shows studies and experiments researching the impact of manufacturing tolerances of permanent magnets and wrong mounting on the rotor on cogging torque . The second part focus on analytical aproach of defining influence of permanent magnets on magnetic flux density in the air gap and phase induced voltage. Practical part focus on design of a prototype machine, wich will be used to research the impact of tolerances and imperfections. Parametric model of the prototype machine is created in Maxwell and is subjected to analysis via finite element method. Three different analysis were run, offset of permanent magnet, decrease and wrong dicertion of magnetization. At last the result of cogging torque and induced voltage are compared.
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Virtual Reality und Augmented Reality als Werkzeug in der AufstellplanungMögel, Jens January 2016 (has links)
Aus Einleitung und Motivation
"Die gegenwärtigen Entwicklungen von Head-Mounted Displays (HMD, hier synonym auch als Brille bezeichnet) für Virtual Reality (VR) und Augmented Reality (AR) schaffen ein nie da gewesenes Potential dieser Technologien als Werkzeuge in der Produktentwicklung. Wenngleich VR- und ARAnwendungen keineswegs neu in der Industrie sind, bringt der Fortschritt der Verbraucher-HMDs völlig neue Möglichkeiten. Immersive VR-Systeme bedeuten künftig keine hunderttausend Euro Anschaffung mehr – AR-Brillen dienen zukünftig nicht nur der Erweiterung der Realität mit zweidimensionalen Informationen.
Cave Automatic Virtual Environments (CAVE), 360-Grad-Projektoren und interaktive Planungstische sind in der Fabrikplanung teilweise etabliert (Runde et al. 2015). Im Unterschied zu diesen Techniken können HMDs jedoch eine deutlich höhere Immersion ermöglichen, was auch für die Interaktion mit der virtuellen Umgebung von Vorteil sein kann. Das Gefühl der Immersion ist wichtig, um in bestimmten Entwicklungsphasen entsprechende Kriterien besser beurteilen zu können. Primär ist der VR-Einsatz für Bewertungsmerkmale sinnvoll, welche nur qualitativ und nicht quantitativ bewertbar sind (Pawellek 2014). Des Weiteren spielt auch die Eingabetechnologie eine essenzielle Rolle. Um mit virtuellen Elementen interagieren zu können, sollte das Eingabegerät echtzeitfähig und intuitiv sein. ..."
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Fatigue analysis of two wheel‐ mounted brake disc designsDuranton, Coralie January 2015 (has links)
Due to a need of more compact bogies, the brake discs can be mounted on the railway wheels, bolted through the wheel web. Thus, the wheels are drilled and have multiple areas of contact with the brake discs. To establish maintenance procedures that will be applied to the wheels, SNCF used the feedback from experience (as with the train AGC) which gives perfect performance in terms of safety. However, to optimize the maintenance process, numerical simulations may be preferred since they are less conservative. This report describes the numerical simulations, based on the finite element method, that were conducted to determine if the Régiolis wheel complies with the standard EN 13979-‐1 from a mechanical fatigue point of view. In addition, it provides additional insights regarding the loads and damage suffered by the wheel, which are not taken into account in the standard: the damage induced by disc braking and the fretting that may occur at the contact interfaces. This study has been used as a decision support for the first inspection intervals of the Régiolis wheels.
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Undersökning av potential för takmonterade PV-system i ett radhusområde i Gävle. : Simuleringar av PV-moduler i IDA ICE 5.0 BetaHalvarsson, Mattias, Aho, Mikael January 2022 (has links)
Sverige har som mål att år 2040 ha helt förnybar elproduktion och därmed utredsalternativ som till exempel vind- och solenergi till elförsörjning där främstsolenergin har potential för mindre och medelstora system för privatpersoner ochföretag. Som en del i denna utveckling har bostadsrättsföreningen Stenbär i Gävlebörjat intresserat sig för att installera solcellssystem, vilket blev grunden för dettaprojekt. Målet med den här utredningen var att utreda områdets potential för ensolcellsanläggning samt hur många kilowattimmar denna skulle kunna genereraper år.Inledningsvis var intentionen att utföra simuleringarna i IDA ICE 4.8, men underförberedelserna inför arbetet uppmärksammades ett webinar på Youtube där IDAICE 5.0 beta presenterades. Equa Simulations AB, vilka har utvecklatprogrammet, förklarade där uppdateringar och styrkor med den nya versionen. Iden nya versionen finns nu möjlighet att upprätta och simulera mer komplexasolcellsystem samt få ut mer korrekta och mer detaljerade resultat. På så vis bleväven en mindre analys av IDA ICE 5.0 beta en del av det här examensarbetet.Mätningar av husens höjd och längd samt avstånd till omkringliggande skogutfördes på plats och takens lutning beräknades till 14,5°. Ritningar över områdettilldelades av uppdragsgivaren och klimatdata återfanns i mjukvaran. En kartbildfrån Google maps behandlades i Photoshop till grund för modellering i IDA ICE.Byggnaderna delades sedan upp i två kategorier, sydlig och öst/västlig riktning.Inga moduler placerade i nordlig riktning simulerades då det inte förväntades varalönsamt. Solcellerna placerades i två lutningar, 14,5° som är takens lutning och45° vilken är den lutning som används av Energimyndigheten vid deras tester avsolcellssystem. Jämförelsen av taklutningarna visade dock endast en skillnad på2,5 %. Då all information om byggnaderna ej varit tillgänglig har områdetsenergibehov, utifrån schablonvärden, beräknats till 64 kWh/m2 och totalt522 MWh/år. Detta för att kunna ställa den i proportion mot solcellsystemetspotentiella elproduktion, vilken i simuleringsresultaten uppgick till 554 MWh/år.Systemkostnaden för det fullstora modellerade systemet landade på 10 600 kronorper installerad kilowattpeak respektive 2 025 kronor per installerad kvadratmetersolpanel. Om återbetalningstiden sätts till 10 år ger det en systemkostnad på 1.17kronor per producerad kilowattimme. Undersökningen visar att potential finns attproducera en stor mängd solel i området. Då systemet producerar ett överskottunder sommarhalvåret finns även möjlighet att sälja el. / Sweden’s energy policy objectives aim to have strictly renewable energyproduction by the year 2040. Alternatives such as wind- and solar power aretherefore implemented as alternatives to fossil fuel where solar power has thebiggest potential for small and medium sized systems for private houses andsmaller companies. As a part of this development homeowner’s association BRFStenbär i Gävle have considered installing PV-systems in their residential areaand that became the foundation for this master thesis. The goal with this projectwas to investigate the residential areas potential for solar powered electricityproduction and how much energy it may produce per year.The simulations were initially meant to be made in IDA ICE 4.8, but during thepreparations a webinar on Youtube was found where the beta version of IDA ICE5.0 was presented. In the presentation Equa Simulations AB, who are thedevelopers of the programme, explained the updates and new features with thenew version. The new version includes possibilities to model and build morecomplex PV-systems and receive more correct and detailed results. Hence, asmaller analysis of IDA ICE 5.0 beta became a part of this master thesis.Measurements of the building’s height and length and the distance to thesurrounding trees were made on site. Drawings of the residential area wereprovided by the client and the climate data were already installed in the software.A map of the area was downloaded from Google maps, modified in a pictureediting programme and used as a base for the modelling in IDA ICE. Thebuildings were divided into two categories, south and east/west orientation. NoPV-systems were placed and simulated in northern orientation since it was notexpected to be profitable.The solar panels were placed in two different angles, 14.5° which is the angle ofthe roofs, and 45° which is the angle used by the Swedish energy agency for theirtesting of PV-systems. The comparisons only showed a deviation of 2.5 %. Allinformation about the building’s energy needs were not available, so fromstandard values their needs were calculated to be 64 kWh/m2 and in total522 MWh/year. This was made to enable comparisons of their needs with thepotential energy production, which amounted to 554 MWh/year. The system costof the total PV-system amounted to 10 600 SEK/installed kWp and 2 025 SEK/m2installed PV-panel. If the repayment period is set to 10 year the system costbecomes 1.17 SEK/kWh. As the system produces more electricity during summerthan needed there is also a possibility to sell the excess to the grid.
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Analysis of Flow Structures in Wake Flows for Train AerodynamicsMuld, Tomas W. January 2010 (has links)
Train transportation is a vital part of the transportation system of today anddue to its safe and environmental friendly concept it will be even more impor-tant in the future. The speeds of trains have increased continuously and withhigher speeds the aerodynamic effects become even more important. One aero-dynamic effect that is of vital importance for passengers’ and track workers’safety is slipstream, i.e. the flow that is dragged by the train. Earlier ex-perimental studies have found that for high-speed passenger trains the largestslipstream velocities occur in the wake. Therefore the work in this thesis isdevoted to wake flows. First a test case, a surface-mounted cube, is simulatedto test the analysis methodology that is later applied to a train geometry, theAerodynamic Train Model (ATM). Results on both geometries are comparedwith other studies, which are either numerical or experimental. The comparisonfor the cube between simulated results and other studies is satisfactory, whiledue to a trip wire in the experiment the results for the ATM do not match.The computed flow fields are used to compute the POD and Koopman modes.For the cube this is done in two regions of the flow, one to compare with a priorpublished study Manhart & Wengle (1993) and another covering more of theflow and especially the wake of the cube. For the ATM, a region containing theimportant flow structures is identified in the wake, by looking at instantaneousand fluctuating velocities. To ensure converged POD modes two methods toinvestigate the convergence are proposed, tested and applied. Analysis of themodes enables the identification of the important flow structures. The flowtopologies of the two geometries are very different and the flow structures arealso different, but the same methodology can be applied in both cases. For thesurface-mounted cube, three groups of flow structures are found. First groupis the mean flow and then two kinds of perturbations around the mean flow.The first perturbation is at the edge of the wake, relating to the shear layerbetween the free stream and the disturbed flow. The second perturbation isinside the wake and is the convection of vortices. These groups would then betypical of the separation bubble that exists in the wake of the cube. For theATM the main flow topology consists of two counter rotating vortices. Thiscan be seen in the decomposed modes, which, except for the mean flow, almostonly contain flow structures relating to these vortices. / QC 20100518 / Gröna Tåget
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EXPERIMENTAL INVESTIGATION OF REPAIR TECHNIQUES FOR DETERIORATED END REGIONS OF PRESTRESSED CONCRETE BRIDGE GIRDERSWilliam Rich (10713612) 06 May 2021 (has links)
<div>
<p>Due to harsh environmental conditions, the deterioration of
prestressed concrete bridge girders is a commonly observed phenomenon in
Indiana and much of the Midwest. Concordantly, one widely observed damage
scenario is deteriorated end regions of prestressed concrete girders. Damaged
or failed expansion joints expose prestressed concrete girder end regions to
chloride-laden water, resulting in a corrosive environment in which
reinforcement section loss and concrete spalling can occur. For bridges
experiencing this type of deterioration, action is needed to ensure the
structure remains safe and serviceable. As
such, an experimental program was developed to investigate the effectiveness of
three repair techniques in restoring the structural behavior of prestressed
concrete bridge girders with end region deterioration. The three examined
repair techniques are (i) an externally bonded fiber reinforced polymer (FRP)
system, (ii) a near-surface-mounted (NSM) FRP system, and (iii) a concrete
supplemental diaphragm. Additionally, installation procedures for the three end
region repair techniques were developed. Results, conclusions, and
recommendations from the experimental program are presented to help advise best
practices for implementing end region repair techniques in the field. </p>
</div>
<br>
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Optimization of operative planning in rail-road terminalsBruns, Florian 16 September 2014 (has links)
Rail-road terminals are the chain links in intermodal rail-road transportation where standardized load units (containers, swap bodies and trailers) are transfered from trucks to trains and vice versa. We consider three subproblems of the operational planning process at rail-road terminals that terminal operators are facing in their daily operations. These are the optimization problems storage planning, load planning and crane planning. The aim of storage planning is to determine load unit storage positions for a set of load units in a partially filled storage area. Here, different restrictions like non-overlapping of stored load units have to be respected. The objective of storage planning is to minimize the total transportation costs and the number of load units that are not stored at the ground level. For the load planning we assume a scenario of overbooked trains. So, the aim of load planning is to assign a subset of the load units that are booked on a train to feasible positions on the wagons such that the utilization of the train is maximized and the costs for the handling in the terminal are minimized. For the feasible positioning of load units length and weight restrictions for the wagons and the train have to be respected. For the load planning of trains we consider a deterministic version and a robust approach motivated by uncertainty in the input data. The last considered optimization problem is the crane planning. The crane planning determines the transfer of the load units by crane between the different transportation modes. For each crane a working plan is computed which contains a subset of the load units that have to be handled together with individual start times for the transfer operations. For the load units which have to be transfered in the terminal, storage and load planning compute destination positions (inside the terminal). These destination positions are part of the input for the crane planning. The main objective of crane planning is to minimize the total length of the empty crane moves that have to be performed between successive transports of load units by the cranes. We provide MIP-models for all three subproblems of the operational planning process at rail-road terminals. For the storage and crane planning we also propose fast heuristics. Furthermore, we present and compare computational results based on real world data for all subproblems. The main contributions of this thesis concern load and storage planning. For the deterministic load planning we provide the first model that represents all practical constraints
including physical weight restrictions. For the load planning we furthermore present robustness approaches for different practical uncertainties. For the storage planning we provide complexity results for different variants. For the practical setting we developed a heuristic which is able to compute solutions of high quality in a small amount of runtime.
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Aspekte zur Entwicklung von industriellen Augmented Reality LösungenBaron, Lukas, Freund, M., Martin, Christopher, Braune, Annerose 20 February 2019 (has links)
Anwendungen unter Einsatz von Augmented Reality (AR)-Technologien gewinnen zuneh-mend an Relevanz in diversen industriellen Anwendungen, zum Beispiel für Produktpräsenta-tionen, Ausbildung und Lehre, Engineering, etc. Bei der Entwicklung solcher Anwendungen – im Speziellen von Bedien- und Beobachtungslösungen – müssen verschiedene Normen und Richtlinien beachtet werden, um zu gewährleisten, dass Anforderungen an die Betriebssi-cherheit in der jeweiligen Anlage eingehalten werden. In diesem Beitrag sollen einige Aspekte bezüglich der Anwendbarkeit solcher Richtlinien auf AR Anwendungen untersucht werden. Darüber hinaus werden weitere Aspekte betrachtet, die bei der Einführung von AR Anwen-dungen im großen Maßstab relevant sind, wie etwa die durchgängige Nutzbarkeit von CAD-Anlagenmodellen zur automatischen Erzeugung von AR-Lösungen. Schließlich stellen wir eine Fallstudie einer AR-Anwendung für eine prozesstechnische Kleinversuchsanlage vor.:1. Einleitung
2. Entwicklungsphasen von AR-Anwendungen
3. Betrachtung der UI-Gestaltungsrichtlinien
4. Fallstudie
4.1. Implementierung
4.2. Ergebnisse
5. Evaluation eines durchgängigen Entwurfsprozesses
6. Zusammenfassung und Ausblick
7. Danksagung / Augmented Reality (AR) applications gain more and more relevance in various industrial ap-plications lately, e. g. for product presentations, education, engineering, etc. In the industrial domain, especially in process supervision applications, a number of standards and guidelines have been established to ensure that the design of user interfaces meets the safety require-ments of plants or factories. Hence, we seek an evaluation if these guidelines can be applied to AR applications. Moreover, there are other aspects to consider in case AR solutions shall be applied on a larger scale in industrial applications. Thus, it is being discussed whether CAD plant models can be used to generate AR applications automatically. Finally, in this contribu-tion, we present the first preliminary results of a case study on the application of those stand-ards to a visual AR application for in-field inspection and servicing scenarios.:1. Einleitung
2. Entwicklungsphasen von AR-Anwendungen
3. Betrachtung der UI-Gestaltungsrichtlinien
4. Fallstudie
4.1. Implementierung
4.2. Ergebnisse
5. Evaluation eines durchgängigen Entwurfsprozesses
6. Zusammenfassung und Ausblick
7. Danksagung
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The Bones of the Horse: A Personal and Cultural HistoryMohler, Sarah Lynn 21 April 2020 (has links)
No description available.
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Haptic Navigation in Virtual Reality : Investigating and developing guidelines for vibrotactile feedback using multiple types of information simultaneouslyDavidsson, Victor January 2018 (has links)
In recent years, progress has been made regarding the use of tactile devices such as belts and helmets for navigational tasks. As most of the devices and solutions so far have focused on presenting one type of information at a time, the potential for tactile devices for simultaneous multiple tasks have yet to be properly explored. Based on such research, this study investigates various methods of presenting multiple simultaneous information using a vibrotactile head-mounted device for navigational tasks in a virtual space. The goal is to determine if it is possible to effectively present various simultaneous navigational information with vibrotactile feedback in a virtual space, and if so, determine guidelines for doing so while avoiding cognitive overload. Using a tactile head-mounted device known as the Perman Helmet various functions related to several navigational tasks in a virtual space were developed. These tasks were collision avoidance, object search and compass orientation. First a test was conducted to determine the most suitable solution for each given task. For each task three different types of solutions were developed, tested, and evaluated in an appropriate testing scenario. Afterwards, a second test was conducted to determine guidelines for how to combine those various solutions to present as much information as possible while avoiding cognitive overload. A new testing environment was created that incorporated all three tasks and various combination of the solutions were tested, along with two special configurations to test other factors. The results from the experiments shows that using several simultaneous vibrotactile signals representing different types of information is feasible and practical with at least 3 different types of signals. Furthermore, various types approaches and combinations have been considered and compared. Based on these findings, several guidelines when developing systems informing a user with multiple vibrotactile feedback signals have been proposed. These findings could help hasten the development of commercial and industrial multiuse vibrotactile devices, making it a relevant field of study. / Under senare år har en rad framsteg gjorts i utveckling av haptiska enheter så som bälten och hjälmar för navigation. Då fokus har legat på att en enhet ska lösa ett specifikt problem saknas det ordentlig utredning av haptiska enheters potential att hantera flera uppgifter simultant. Baserat på tidigare forskning utforskas det i denna rapport olika metoder att presentera multipla simultana informationsflöden via en vibrotaktil huvudmonterad enhet i syfte att navigera en virutell miljö. Baserat på om dessa metoder kan användas effektivt utan att överbelasta en användare tas därefter riktlinjer för sådana system fram. Med hjälp av en taktil huvudmonterad enhet kallad Perman Hjälmen togs en rad funktioner ämnade för att navigera i en virtuell rymd fram. Dessa funktioner var kollisionsförebyggande system, målsökning samt kompassorientering. För varje funktion togs tre olika lösningar fram och utvärderades i en lämplig miljö. Efteråt utfördes ett andra experiment för att ta fram riktlinjer för hur olika lösningar för olika uppgifter bör kombineras för att presentera maximal mängd information utan att överbelasta användare. En ny anpassad testmiljö utvecklades och olika kombinationer av lösningar till de olika uppgifterna utvärderades. Även två specialkonfigurationer togs fram för att testa specifika faktorer. Resultaten från experimenten visade att använda flera simultana vibrotaktila informationsflöden var praktiskt möjligt med åtminstone tre distinkta typer av flöden. Utöver detta har olika tillvägagångssätt och kombinationer övervägts och jämförts. Baserat på detta har flera riktlinjer tagits fram för utveckling och vidareforskning av system med multipla simultana vibrotaktila informationsflöden. Dessa slutsatser kan komma att bidra till vidareutveckling av framtida kommersiella och industrianpassade vibrotaktila enheter, vilket gör detta ett relevant forskningsområde.
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