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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

Design Philosophy for User Friendly Parameter Handler

Angarita Soto, Angie January 2012 (has links)
DCU2 (Drive Control Unit 2) is an important control system used in applications for train systems that are configured by a set of parameters. Traditionally, parameterization is conducted by using an excel workbook during the software development. The parameters are set up and further export the parameters to the compilation step. Such approach has a number of disadvantages, e.g., delays on the validation and verification steps, system configuration overhead, and suboptimal system reliability generated by the parameter configurations. To improve the parameterization process, this thesis implements a model-based software architecture approach and automotive industry standards via rapid prototyping by using scrum methodology. We do this by using Matlab/Simulink, TDL (Time Description Language) and UML (Unified Modeling Language) architectural description languages to enable different views of the software architecture. We then develop different prototypes that implement ASAM (Association for Standardization of Automation and Measuring Systems) standards like XCP protocol over Ethernet (code ASAM MCD-1 XCP V1.1.0) and ASAP2 (code ASAM MCD-2 MC) in every scrum sprint. An evaluation then shows that the thesis successfully implements previously defined standards that use commercial tools from e.g., Vector, proving that the parameter‟s unit control can be handled via online calibration and measurement, leading to a significant improvement in Bombardier‟s software development process in a distributed development environment.
2

Zalomený řetězový dopravník / Cranked chain conveyer

Komínek, Vojtěch January 2008 (has links)
Output of this diploma work is an overall project of the Cranked Chain Conveyer, arising from specification of the assignment. Project is divided into several phases, whereas first of them is composed of calculations and finding of necessary driving unit. First phase is followed by second phase, where I - regarding the engine power - dimension individual structural parts like loop chain, conveyer drive unit, stressing etc. In last phase I deal with drawing documentation of designed parts of the conveyer.
3

Návrh hydraulického pojezdu univerzální pohonné jednotky žacího stroje / Design of hydraulic travel of reaper`s drive unit

Smejkal, David January 2012 (has links)
This diploma thesis deals with a design of hydraulic reaper’s drive unit and continual realization of its real prototype. The unit is designed with freelance wheel drive, continual change of speed and direction. A part of a drive unit is a remote control, which is primarily used for control of movement and mowing. On the base of research analysis the conception design was created, which has to fulfill all the needed requirements for build of prototype and its subsequent testing. Engineering design was performed in Autodesk Inventor 2012. Realized prototype was built by sponsor company. The components were chosen with regard to their functionality, quality and cost.
4

Redesign of linear drive unit for wheelchair lifts for trains

Meyer-Dietrich, Simon January 2024 (has links)
The UPL-300 is a fully electric wheelchair lift for trains. Many wheelchair lifts for trains exist on the market but the vast majority are driven by hydraulics. Electric drive prevents potential hydraulic fluid spills and negates the need for special disposal of the fluid. The aim of this project was to improve this lift because it struggled to compete on that market and no longer met industry standards. This project first identified which areas of the UPL-300 needed improving and then worked on two of these areas, the linear drive unit (LDU) which enables the lift to go up and down and the wall brace which connects the linear drive unit to the wall of a train car. The results were a design document for the wall brace and a new design for the LDU. The wall brace design document aimed to simplify and expedite the design process of the customer specific wall brace. The new LDU cut the cost for the lift significantly and fulfilled the requirements of modern standards. The design of the new LDU is easily scalable and has the potential to be used as a linear actuator in other products. The improvement analysis, together with the other work done in this project, laid a strong foundation for future work to improve the UPL-300 fully electric wheelchair lift for trains.
5

Zástavba pohonné jednotky LYCOMING do letounu Bristel UL / Installation of the LYCOMING power unit into the Bristel UL aircraft

Kročil, Petr January 2020 (has links)
This diploma thesis focuses on Lycoming drive unit mounting used in two-seater plane of VLA category (the very light aircraft). In the beginning characteristics of currently produced Bristell aircrafts are described. Following chapters aim at research selection of new drive unit mounting based on multi-criteria decision analysis. For selected unit, the weight, center of mass and flight performance are calculated. Additionally, the construction of engine mount is proposed. According to CS-VLA and CS-23 stress level of mounting is defined followed by strength verification. Later in this thesis, a suitable engine cover for engine and cockpit cooling is proposed. A complete fuel system is described in following chapter. Last chapter deals with financial costs of re-engining as well as aircraft operational costs.
6

Dynamic behavior characterization of a Power Transfer Unit using Multi Body Simulation / Simulering av en vinkelväxels dynamiska beteende

Lingaiah, Puneeth January 2018 (has links)
Vinkelväxlar och slutväxlar spelar en viktig roll för kraftöverföringen mellan motor och hjuli fyrhjulsdrivna bilar. Med en ökande konkurrens finns en efterfrågan för att ständigt förbättraeffektivitet, ljudgenereringegenskaper och hållfasthet. För att uppnå detta krävs en bättreförståelse av systemets dynamiska egenskaper. En detaljerad numerisk dynamisk modell ärdock ofta beräkningsmässigt tung och tidskrävande. Verktygen för den dynamiska modelleringenbehöver bli mer effektiva och i vissa fall kan en kombinationen av två verktyg vara ett bättrealternativ. Denna integrerade plattform kan användas för att effektivt modellera dynamiken ochfå en bättre inblick i systemts beteende.Vinkelväxlen är en enhet vars funktion är att fördela kraften mellan fram- och bakaxel. De viktigastekomponenterna i vinkelväxeln är en hypoid-drevsats och en klokoppling, som aktiveras närkraft ska överföras till bakaxeln via kardanaxeln. Detta arbete modellerar dynamiskt beteendei vinkelväxeln och har sytftet att beräkna transmissionsfelet i systemet och dess effekt somexciteringskälla av ljud och vibrationer i systemet. MSC ADAMS har använts för Multi-Bodyberäkningsverktyg för modelleringen.Det beräknade transmissionsfelet har jämfört med testresultat. Dessutom har en co-simuleringmed både ADAMS och SIMULINK genomförts för att skapa en bas för tillämpa optimeringsalgoritmer.Bultarna i bultförbandet samt deras styvhet och förspänning har inkluderats i modellenoch studerats med avseende på effekten på vibrationer i kopplingspunkter, samt algoritmerför optimering har föreslagits. Korrelationen mellan test och beräkning var mycket god, ochdessutom har förslag på hur denna typ av beräkning kan förbättras ytterligare givits. / Automotive drive units play an important role in transmitting power from an engine to the wheels.In today’s competitive world, there is an increasing demand for these devices to be more efficient,quiet, and reliable at the same time. In order to achieve this, a better understanding of system’sdynamic behavior is necessary. A detailed dynamic model of a system is often computationallyintense to solve and time consuming. This demands more efficient tools to be developed and insome cases integrating two or more tools would be a better option. The integrated platform can beused to effectively model the dynamic behavior of a system and get better insights on the systembehavior.Power Transfer Unit (PTU) is a device whose function is to distribute power between a front axleand rear axle. This unit basically includes hypoid gear set and a dog clutch that is engaged whenthere is a requirement to transfer power to the Rear Drive Unit (RDU) through prop shaft. Thismaster thesis describes modeling the dynamic behavior of a PTU with a goal of predicting thetransmission error in the system and its effect as a source of excitation on the entire unit followedby studying system response to this type of excitation. MSC ADAMS was used as a Multi-BodySimulation tool to model the dynamic behavior of the PTU.The transmission error predicted by the simulation was compared with the test results, a cosimulationbetween SIMULINK and ADAMS was established in order to create a platform toapply optimization algorithms. The bolt and bearing stiffness were incorporated in the model andtheir effect on the mounting point accelerations and bearing point accelerations were studied. Itwas found that the bolt stiffness affects the acceleration levels at the coupling points and suitablealgorithms could be applied in order to find an optimum value. As a result of the good correlationbetween test and simulation data, some other useful conclusions have been derived in order todevelop this approach of modeling.
7

Design of transport solution for truck plant line simulator

Tjernström, Oskar, Wiklund, Alfred January 2023 (has links)
Volvo Trucks is the second-largest heavy-duty truck provider in the world. As of now they are working towards fossil free transport solutions. This comes with a fast development pace and an increasing need of being able to verify new and complex assembly processes to ensure an integration of the production of new truck models together with the current vehicles that are being produced.  This project is a master thesis that focuses on improving the quality and verification capabilities of the Pilot Plant at the Volvo Tuve site. The goal of the project is to design and develop a modular transport solution that can be used to move truck chassis at a predefined speed to be able to simulate and perform assembly tasks with the same parameters in the test environment as in the factory process along the driven line. The design was developed using the product development process described by Ulrich et al., 2020, with slight modification. The resulting design is able to move the truck chassis at the requested predefined speeds that are possible on the driven line in the factory. This solution gives Volvo the ability to perform simulations of specific and critical assembly steps, potentially resulting in fewer failures during production ramp-up of their new truck models.  Calculations were made to in order to verify the strength and functionality of the design.
8

Ruggedness of High-Voltage IGBTs and Protection Solutions / Robustheit von Hochspannungs-IGBTs und Schutzmöglichkeiten

Basler, Thomas 13 August 2014 (has links) (PDF)
IGBTs are today’s most important power-semiconductor switches in the field of medium and high power ranges. The good controllability of this device with a voltage source is advantageous. The following work investigates the IGBT at short-circuit and surge-current condition. A particular focus is put on the IGBT’s feedback on the gate-control circuit. Special modes during the short circuit are measured and explained. For example the self-turn-off mechanism during short circuit and the collector-emitter voltage-clamping capability during fast short-circuit turn-off. Measurements are done at high-voltage IGBT chips and press-pack devices. The complete IGBT output characteristic up to the breakdown point is measured. Additionally, the short circuit is investigated at the parallel and series connection of IGBTs. Supporting semiconductor simulations of a high-voltage IGBT model, that was specially constructed for this work, analyse the internal behaviour during the mentioned conditions. The impact of different IGBT designs on the short-circuit ruggedness and breakdown behaviour is shown. Solutions for protecting the device from destruction during overload condition are presented. Measurements and simulations explain the surge-current capability of an IGBT and demonstrate the benefit for the application. / IGBTs gehören zu den wichtigsten Halbleiter-Leistungsbauelementen im mittleren und oberen Leistungsbereich. Die einfache Ansteuerbarkeit durch eine Spannungsquelle ist dabei von großem Vorteil. Nachfolgende Untersuchungen beschäftigen sich mit dem IGBT-Kurzschluss und -Stoßstrom. Ein besonderes Augenmerk wird auf die Rückwirkung des IGBTs auf den Ansteuerkreis gelegt. Spezielle IGBT Modi werden gemessen und erklärt. Hierzu zählen zum Beispiel der Self-Turn-Off Mechanismus während des Kurzschlusses und die selbständige Kollektor-Emitter Spannungsbegrenzung während schnellen Kurzschlussabschaltens. Hierfür werden Messungen an Hochspannungs-IGBT Chips und Press-Pack IGBTs durchgeführt. Des Weiteren wird das komplette Ausgangskennlinienfeld des IGBTs vermessen und das Kurzschlussverhalten in der Parallel- und Reihenschaltung untersucht. Halbleitersimulationen eines Hochspannungs-IGBT Modells zeigen das interne IGBT Verhalten und unterstützen die Analyse der Messungen. Der Einfluss unterschiedlicher IGBT Designs in Bezug auf die Kurzschluss-Robustheit und das Durchbruchverhalten wird aufgezeigt. Möglichkeiten zum Schutz des IGBTs vor Zerstörung werden erörtert. Messungen und Simulationen zeigen die gute Stoßstromfestigkeit von IGBTs bei erhöhter Gatespannung auf. Davon kann die komplette Anwendung profitieren.
9

Ruggedness of High-Voltage IGBTs and Protection Solutions

Basler, Thomas 28 February 2014 (has links)
IGBTs are today’s most important power-semiconductor switches in the field of medium and high power ranges. The good controllability of this device with a voltage source is advantageous. The following work investigates the IGBT at short-circuit and surge-current condition. A particular focus is put on the IGBT’s feedback on the gate-control circuit. Special modes during the short circuit are measured and explained. For example the self-turn-off mechanism during short circuit and the collector-emitter voltage-clamping capability during fast short-circuit turn-off. Measurements are done at high-voltage IGBT chips and press-pack devices. The complete IGBT output characteristic up to the breakdown point is measured. Additionally, the short circuit is investigated at the parallel and series connection of IGBTs. Supporting semiconductor simulations of a high-voltage IGBT model, that was specially constructed for this work, analyse the internal behaviour during the mentioned conditions. The impact of different IGBT designs on the short-circuit ruggedness and breakdown behaviour is shown. Solutions for protecting the device from destruction during overload condition are presented. Measurements and simulations explain the surge-current capability of an IGBT and demonstrate the benefit for the application. / IGBTs gehören zu den wichtigsten Halbleiter-Leistungsbauelementen im mittleren und oberen Leistungsbereich. Die einfache Ansteuerbarkeit durch eine Spannungsquelle ist dabei von großem Vorteil. Nachfolgende Untersuchungen beschäftigen sich mit dem IGBT-Kurzschluss und -Stoßstrom. Ein besonderes Augenmerk wird auf die Rückwirkung des IGBTs auf den Ansteuerkreis gelegt. Spezielle IGBT Modi werden gemessen und erklärt. Hierzu zählen zum Beispiel der Self-Turn-Off Mechanismus während des Kurzschlusses und die selbständige Kollektor-Emitter Spannungsbegrenzung während schnellen Kurzschlussabschaltens. Hierfür werden Messungen an Hochspannungs-IGBT Chips und Press-Pack IGBTs durchgeführt. Des Weiteren wird das komplette Ausgangskennlinienfeld des IGBTs vermessen und das Kurzschlussverhalten in der Parallel- und Reihenschaltung untersucht. Halbleitersimulationen eines Hochspannungs-IGBT Modells zeigen das interne IGBT Verhalten und unterstützen die Analyse der Messungen. Der Einfluss unterschiedlicher IGBT Designs in Bezug auf die Kurzschluss-Robustheit und das Durchbruchverhalten wird aufgezeigt. Möglichkeiten zum Schutz des IGBTs vor Zerstörung werden erörtert. Messungen und Simulationen zeigen die gute Stoßstromfestigkeit von IGBTs bei erhöhter Gatespannung auf. Davon kann die komplette Anwendung profitieren.

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