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Effect of geometric, material and operational parameters on the steady-state belt response for flat belt-drivesYildiz, Cagkan 05 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / This thesis presents a comprehensive study of the effects of material, geometric and operational parameters on flat belt-drives steady-state belt stresses, belt slip, and belt-drive efficiency. The belt stresses include: belt rubber shear, normal, axial and lateral stresses; reinforcements tension force; and tangential and normal belt-pulley contact stresses. Belt slip is measured using the driven over driver pulleys’ angular velocity ratio. Each parameter was varied over a range to understand its impact on the steady-state belt-drive response. The material parameters studied are belt axial stiffness and damping, belt bending stiffness and damping, and belt-pulley friction coefficient. The geometric parameters studied are pulley center distance, pulleys diameter ratio, and belt thickness. The operational parameters studied are the driver pulley angular velocity and the driven pulley opposing torque (load).
A high-fidelity flexible multibody dynamics parametric model of a two-pulley belt-drive system was created using a commercial multibody dynamics code. In the model the belt’s rubber matrix is represented using three-dimensional brick elements and the belt’s reinforcements are represented using one dimensional beam elements at the top surface of the belt. An asperity-based Coulomb friction model is used for the friction forces between the pulley and belt. The pulleys are modeled as rigid bodies with a cylindrical contact surface. The equations of motion are integrated using an explicit solution procedure.
Unlike prior models which use one-dimensional truss or beam elements for the belt, the present model uses a three-dimensional belt model which introduces the effect of the thickness of the belt rubber matrix (modeled using brick elements). This enables a more accurate prediction of the belt stresses and slip than prior models. This thesis resolves in more details the complex stick-slip friction behavior of an axially flexible belt coupled with the shear effects of a flexible rubber cushion and at the same time shows the effect of the main system parameters on this stick-slip behavior. Some of the important conclusions of the thesis include: (1) the driver pulley has two distinct contact zones - a negative traction zone and a positive traction zone - while only one traction zone is present over the driven pulley; (2) the width of the negative traction zone on the driver pulley increases with the belt-pulley coefficient of friction and decreases with the belt axial stiffness; (3) the maximum belt tension and normal contact stress occur on the driver pulley and increase with the belt thickness, belt axial stiffness, and coefficient of friction; (4) belt-drive energy efficiency increases with the belt axial stiffness, and decreases with belt thickness, belt bending damping, belt operating speed, and operating torque load. The belt-drive modeling methodology presented in this thesis which enables accurate prediction of the belt stresses and slip can in turn be used to more accurately predict the fatigue life, wear life, and energy efficiency of belt-drives.
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Interakce mobilních pracovních strojů a pojížděného podloží / Interaction between Mobile Working Machines and Rolled SurfacesPokorný, Jan January 2010 (has links)
This dissertation thesis is concerning with an interaction between mobile working machines and rolled surfaces. Machines and their constructions parts behavior were observed. There are some machines that can change state of surface. And due to these change of surface the machine is in different conditions for drive and also for works. The interaction of working machines and rolled surfaces was categorized in this work and for each category here is a methodic work flow for solution of various cases. Three examples are described in this work. Some simulating programs were used for all cases and therefore there is a methodic work flow for creating and simulating of models. Three described examples include a complex solution of hydraulic drive for vibration exciter of vibration roller, small cleaner of canalizations with aim on load case to frame of this cart. The third example describes solution of undercarriage frames of agricultural semi-trailers. This example is the most extensive chapter from this work due to including of marketing research at the beginning of development and also verification of simulated results with results from real prototype tests at the end of development of these undercarriage frames.
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Fault Diagnosis for Functional Safety in Electrified and Automated VehiclesLi, Tianpei 25 September 2020 (has links)
No description available.
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804 |
Data Engineering and Failure Prediction for Hard Drive S.M.A.R.T. DataRamanayaka Mudiyanselage, Asanga 08 September 2020 (has links)
No description available.
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805 |
Field Experimentation and Finite Element Analysis of Prominent Drive-by Bridge Inspection TechniquesBrooker, Caden B. 25 May 2021 (has links)
No description available.
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806 |
9. Kolloquium Getriebetechnik: TagungsbandBerger, Maik January 2011 (has links)
Das Kolloquium Getriebetechnik findet seit 1995 im zweijährigen Turnus statt. Im aktuellen Tagungsband zum 9. Kolloquium in Chemnitz werden in 22 Fachbeiträgen aktuelle Lehr- und Forschungsschwerpunkte aus den Gebieten der Bewegungs-, Getriebe,- und Antriebstechnik, Berechnung und Simulation bis hin zu internetbasierten Wissensportalen vorgestellt. Besondere Themenschwerpunkte sind einerseits die aktuellen und zukünftigen Ausbildungsstrategien im Themengebiet der ungleichmäßig übersetzenden Getriebe an den Universitäten und Fachhochschulen. Andererseits werden die aktuellen F&E-Aktivitäten der einzelnen Professuren und Institute sowie Applikationen von Firmen präsentiert. Dabei stehen heute neben den mechatronischen Antriebssystemen auch verstärkt werkstofftechnisch bzw. bionisch geprägte Konzeptideen im Focus. Neben neuen und effizienten CAD-Lösungsstrategien zeigen die Beiträge ganzheitliche Lösungsansätze sowie den Einsatz der Mehrkörpersimulation und FEM im Umfeld der Getriebeentwicklung.
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Indirekte modellprädiktive Regelung von Windenergieanlagen sowie deren energie-optimale und deren schädigungsarme KonfigurationSchwarz, Colin Maximilian 17 May 2023 (has links)
Die vorliegende Arbeit beschäftigt sich mit der Anwendung der indirekten Methoden zur automatisierten Lösung von einer bestimmten Klasse von Optimalen Steuerungsproblemen im Rahmen einer modellprädiktiven Regelung für Windenergieanlagen. In einem zweiten Teil wird der Einfluss dieser Regelungsmethode auf die Festigkeit des Triebstranges untersucht. Diese führt zu einer überproportionalen Beanspruchung und damit zu einer Reduktion der Betriebsfestigkeit. Es gilt entsprechende Randbedingungen für die der Regelung zugrunde liegenden Optimalen Steuerungsprobleme zu finden, so dass weiterhin die Energieausbeute maximiert werden kann, gleichzeitig jedoch die Beanspruchung durch die Regelung begrenzt wird.
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Development of a Compact Drive System for Total Artificial Heart / Utveckling av en kompakt drivenhet för ett totalt artificiellt hjärtaBakhtiari, Hossin January 2023 (has links)
Over eight decades of research into total artificial hearts (TAHs) has significantly contributed to saving end-stage heart failure patients. However, at the current stage of development TAHs have several limitations, one of them being their bulkiness. Hence this thesis, with the goal to evaluate the right pump of the TAH developed by Scandinavian Real Heart and propose a compact right drive system without consuming significantly more power than the initial system. In order to do this, the requirements for the right drive systems are evaluated and defined. These requirements are then used to develop a methodology, including a MatLab simulation, for examining and selecting motors for the drive unit of the TAH. Subsequently, the methodology and the simulation are used to identify and assess over 200 motors, as well as select 3 motors for real-world experimental analysis. The suggested motors and the initial motor are then tested in a mock circulatory loop to investigate the performance characteristics and power consumption of the motors. This is done to select the final motor for the right drive unit, as well as verify and validate the created simulation. Based on careful analysis of the mathematical models used in the simulation and presented experimental data, the simulation was accepted to be verified. However, the support for validation of the simulation was lacking, as conflicting outcome for some cases were observed between the simulation and experimental data. Furthermore, given the empirical evidence, a brushless dc motor for the right drive unit and its implementation was proposed. The proposed motor has 11% reduction in size, 20% reduction in power consumption and 34% reduction in weight compared to the initial motor. Therefore, a drive unit with the suggested motor can have a significant impact on the right pump, and potentially even the left pump. Furthermore, the utilisation of the developed simulation can ultimately result in efficient and cost-effective motor selection and provide valuable contribution to the field of drive system development for TAHs. / Över åtta decennier av forskning om totala artificiella hjärtan (TAH) har omfattande bidragit till att rädda patienters liv med kronisk hjärtsvikt. Dessvärre har TAH flera begränsningar i det nuvarande stadiet i utveckling där storleken är ett problem. Därav denna avhandling, med målet att utvärdera den högra pumpen av en TAH utvecklad av Scandinavian Real Heart, för att föreslå ett mer kompakt höger drivsystem utan att det ska förbruka väsentlig mängd mer energi än det ursprungliga systemet. För att åstadkomma detta, har de fysiologiska krav för den högra pumpen analyserats och utifrån den utförda analysen nya krav för drivsystemet har formulerats. Dessa krav har sedan lagt grunden till utveckling av en metodik, inklusive en MatLab-simulering, för att undersöka och välja motorer för drivsystemet av en TAH. Metodiken i samband med simuleringen har använts för att identifiera och bedöma över 200 motorer. Av dessa motorer har tre motorer valts för experimentell utvärdering. I den experimentella utvärderingen, prestandaegenskaper och effektförbrukning av samtliga valda motorer och den ursprungliga motorn har utvärderats i ett konstgjort cirkulationssystem. Syftet med den experimentella utvärderingen är att komma fram till en slutmotor, samt verifiera och validera den utvecklade simuleringen. Baserad på noggrann analys av de använda matematiska modeller i simuleringen och det presenterade experimentella data, ansågs simuleringen vara verifierad. Däremot saknades stöd för validering av simuleringen, på grund av en del motsägande utfall mellan simulering och experimentell data. Därutöver, utifrån den empiriska evidensen föreslogs en borstlös likströmsmotor och dess implementering för det högra drivsystemet. Den föreslagna motorn är 11% mindre i storlek, har 20% lägre effektförbrukning och väger 34% mindre än den ursprungliga motorn. Därför kan en drivenhet med den föreslagna motorn ha en betydande inverkan på den högra pumpen, och potentiellt även den vänstra. Dessutom kan den utvecklade simuleringen användas för att göra urval av motorer för TAH på ett produktivt samt kostnadseffektivt sätt och därmed bidra till framtida utvecklingar av drivenheter för TAH.
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FPGA Based Lane Tracking system for Autonomous VehiclesRam Prakash, Rohith Raj January 2020 (has links)
The application of Image Processing to Autonomous driving has drawn significant attention in recently. However, the demanding nature of the image processing algorithms conveys a considerable burden to any conventional realtime implementation. On the other hand, the emergence of FPGAs has brought numerous facilities toward fast prototyping and implementation of ASICs so that an image processing algorithm can be designed, tested and synthesized in a relatively short period in comparison to traditional approaches. This thesis investigates the best combination of current algorithms to reach an optimum solution to the problem of lane detection and tracking, while aiming to fit the design to a minimal system. The proposed structure realizes three algorithms, namely Edge Detector, Hough Transform, and Kalman filter. For each module, the theoretical background is investigated and a detailed description of the realization is given followed by an analysis of both achievements and shortages of the design. It is concluded by describing the advantages of implementing this architecture and the use of these kinds of systems. / Tillämpningen av bildbehandling inom autonoma fordon har fått stor uppmärksamhet den senaste tiden. Emellertid förmedlar den krävande karaktären hos bildbehandlingsalgoritmerna en stor belastning på vilken konventionell realtidsimplementering som helst. Å andra sidan har framväxten av FPGAer medfört många möjligheter till snabb prototypering och implementering av ASICar så att en bildbehandlingsalgoritm kan utformas, testas och syntetiseras på relativt kort tid jämfört med traditionella tillvägagångssätt. Denna avhandling undersöker den bästa kombinationen av nuvarande algoritmer för att uppnå en optimal lösning på problemet med spårning och fildetektering, med målet att krympa designen till ett minimalt system. Den föreslagna strukturen realiserar tre algoritmer, nämligen Edge Detector, Hough Transform och Kalman filter. För varje modul undersöks den teoretiska bakgrunden och en detaljerad beskrivning av realiseringen ges följd av en analys av både fördelar och brister i konstruktionen. Avhandlingen avslutas med en beskrivning av fördelarna med att implementera lösningen på det sätt den görs och hur dessa system kan användas.
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[en] DRIVE: A BORDER CONCEPT BETWEEN FREUD AND REICH / [pt] PULSÃO: UM CONCEITO LIMITE ENTRE FREUD E REICHJULIA ALVARES DE ABOIM 09 November 2015 (has links)
[pt] Nesta dissertação o conceito freudiano de pulsão é articulado com a teoria econômico-sexual de Reich. Sob a ótica deste autor a pulsão ganha uma nova leitura que permite rediscutir este conceito sob um viés orgânico-energético. Assim, Reich desenvolve a teoria da libido de Freud, buscando demonstrar que a libido frustrada em sua finalidade (estase libidinal) constitui a fonte de energia que alimenta as neuroses. Em relação à pulsão de morte, Reich argumenta contra a ideia de haver no ser vivo um impulso à morte e, por conseguinte, contra a noção de um masoquismo erógeno, uma autodestruição primária. Dessa forma, ao desconsiderar a primazia da pulsão de morte, o dualismo pulsional, na visão reichiana, também não se sustentaria. / [en] In this thesis the Freudian concept of drive is linked to Reich s sex-economy theory. From the perspective of this author the concept of drive (Trieb) acquires a new interpretation that allows to revisit this concept in an organic-energy view. Reich developed Freud s libido theory, seeking to demonstrate that a frustrated libido (libidinal stasis) is the source of energy supplying the neurosis. Regarding the death drive, Reich argues against the idea of a natural impetus to death and therefore against the notion of an erogenous masochism, a primary self-destruction. Thus, the Reichian vision disregards the primacy of the death drive and rejects the instinctual dualism.
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