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1
Menzel, Daniela, Silke Geithner, and Stefan Donath. ""Projektwerkstatt C2 - Camshaft China"." Universitätsbibliothek Leipzig, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-153487.
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In ihren zukünftigen Tätigkeiten in privatwirtschaftlichen Unternehmen
und öffentlichen Einrichtungen werden aktuell Studierende und Promovierende zunehmend gefordert sein, in interdisziplinären
Projektteams zusammenzuarbeiten. Die Herausforderungen bestehen dabei vor allem darin, innerhalb kürzester Zeit bei allen Projektmitarbeiter_innen ein gemeinsames Verständnis über das
Projektziel und den -inhalt, das Projektmanagement sowie Formen
der kooperativen und effektiven (interkulturellen) Zusammenarbeit
zu erzeugen. Diese Fähigkeiten lassen sich kaum über Frontalunterricht
vermitteln, sondern müssen aktiv selbst erlebt und erworben
werden. Anhand der Aufarbeitung des realen Fallbeispiels eines
international agierenden Automobilzulieferers zum Aufbau eines
neuen Standortes und durch die Nutzung der LEGO® Serious Play®-
Methode (LSP-Methode) werden die Teilnehmer_innen im Rahmen
des entwickelten Planspiels "Projektwerkstatt C2 – Camshaft China"
gefordert, sich damit aktiv auseinanderzusetzen.
2
Báez, Morandi Federico E. "Development of an interactive camshaft design tool." Thesis, KTH, Maskinkonstruktion (Inst.), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-176882.
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Camshafts are crucial components in combustion engines. Their purpose is to control the opening and closing of intake and exhaust valves, which affects various aspects of an engine’s performance. The valves control the intake of the air-fuel mixture in the combustion chamber and the exhaust of combustion gases. The synchronization of this task with the engine’s cycle is essential for the system to work as desired, and timing parameters such as valve duration affect the engine’s power and efficiency. This thesis addresses the development task of a software program for camshaft design. The program must be able to receive input design parameters, process them and provide visual and numerical information for the user to make decisions in the design process. It also needs to be intuitive and provide guidance through a highly iterative process. The program is divided in two parts: cam mechanism and shaft design. The intake and exhaust cams are initially designed in accordance to the desired timing properties of the combustion cycle, the engine speed and the mechanism’s structural properties. They are later included in a shaft with specific structure and dimensions, and its deformations and stresses are analyzed in order to validate the design or back up to a previous step to perform a new iteration. The program is developed entirely in Mathworks Matlab using Matlab’s GUIDE for the GUI design and only standard Matlab libraries. The development method is presented along with the GUI’s description and an application example, using ANSYS to perform a FEM deformation and stress analysis for comparison with the program’s results.Kamaxlarna är viktiga komponenter i förbränningsmotorer. Deras syfte är att styra öppnandet och stängandet av insugnings-och avgasventiler, som påverkar olika aspekter av motorns prestanda. Ventilerna kontrollerar intaget av luft-bränsleblandningen i förbränningskammaren och förbränningsmotorns avgaser. Synkroniseringen av denna uppgift med motorns cykel är avgörande för systemet drift, och timing parametrar såsom ventil varaktighet påverkar motorns effekt och effektivitet. Denna avhandling behandlar utvecklingen av ett program för kamaxel design. Programmet måste kunna ta emot indataparametrar, bearbeta dem och ge visuell och numerisk information så att användaren kan fatta beslut i designprocessen. Det måste också vara intuitivt och ge vägledning genom en mycket iterativ process. Programmet är uppdelat i två delar: kammekanismen och axelns konstruktion. Insugs-och avgas kammar är ursprungligen tänkta i enlighet med önskade tidsegenskaper för förbränningscykeln, motorvarvtalet och mekanismen strukturella egenskaper. De ingår i en axel med specifik struktur och dimensioner, och dess deformationer och spänningar analyseras i syfte att validera designen eller för att säkerhetskopiera till ett tidigare steg för att utföra en ny iteration. Programmet är utvecklat helt i Mathworks Matlab med Matlab's GUIDE för GUI design och använder bara vanliga Matlab-bibliotek. Den utvecklade Metoden presenteras tillsammans med beskrivning av GUI och ett exempel,som verifieras med hjälp av ANSYS genom att utföra en FEM-baserad deformations och spänningsanalys.
3
Escobar, Jose Alejandro. "Stress and fatigue analysis of svi-tested camshaft lobes." Thesis, Virginia Tech, 1996. http://hdl.handle.net/10919/36656.
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Nondestructive evaluation techniques were
employed to fully characterize three 2.3L
camshafts tested in an engine simulator for an
equivalent of 100,000 miles. Optical
microscopy, acoustic microscopy (SAM),
and profilometry were used to characterize
wear and fatigue, crack depth, and surface
roughness, respectively. Results show
cracking to occur mainly in the opening ramp
of the most abusively ground cam lobes. No
clear evidence was found for subsurface
cracking at depths as great as 200 mm from
the lobe's surface. Profilometry results show
no evidence of any major tribological effect
due to the sliding friction of the follower.
Fractography studies show a difference
between fracture surfaces among the cracks
examined; straight cracks exhibit features
resembling fatigue propagation, while fracture
surfaces from pitted cracks show a more
brittle behavior. Small grinding cracks
(approximately 300 mm in length) were found
in the opening ramps of the most abusively
ground lobes prior to testing. Knoop and
Nanoindenter microhardness indicate a
near-surface rehardening for the most
abusively ground lobe (confirmed by
metallography), and temper burn for the
remaining lobes. X-ray residual stress results
made in the opening ramp of the tested lobes
show evidence of residual stress relaxation.
X-ray line width data as a function of depth
does not correlate with residual stress.Master of Science
4
Thomas, George L. "Biogeography-Based Optimization of a Variable Camshaft Timing System." Cleveland State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=csu1419775790.
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5
Stokes, Ben. "Fatigue analysis of austempered ductile iron suitable for automotive camshaft applications." Thesis, University of Southampton, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288156.
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6
Courtney, Scott B. "A rapid, non-destructive test to detect camshaft lobe grinding burn." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-09042008-063602/.
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7
Henschel, Frank. "The reduction of friction in the camshaft of an internal combustion engine." Thesis, Coventry University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360224.
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Benson, Julian. "The effect of base stock and additive packages in an automotive oil on the friction and wear behaviour of overhead camshaft and finger follower systems." Thesis, Brunel University, 1987. http://bura.brunel.ac.uk/handle/2438/7132.
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The introduction of overhead camshaft valve train systems some 25 years ago has resulted in improved engine performance and efficiency, this in turn however, has caused increased wear problems. In order to understand the tribological behaviour of overhead camshaft systems, test engines and dynameter test methods have been extensively used. These are however, time consuming and expensive, a cheaper and quicker method of camshaft material and lubricant appraisal is therefore required and this has resulted in the design and construction of a simulative overhead camshaft test rig. A range of commercially available camshaft and follower materials have been tested using both a fully formulated and a -mineral base -equivalent. The most commonly encountered cam and follower wear failures of scuffing, pitting and polishing were reproduced. Results showed scuffing wear to be associated with all of the camshaft materials using the mineral base oil under high load, boundary lubrication conditions. Scuffing also occurred under low load, mixed lubrication conditions using the case-hardened steel cam and chilled white iron follower combinations. The remaining cam materials, carbonitrided and induction hardened grey flake iron did not fail under similar test conditions due to the presence of free graphite in the icrostructure. The fully formulated oil generally suppressed the onset of scuffing under all test conditions due to the presence of the zinc-dialkyldithiophosphate (Z.D.D.P) anti-wear additive in the oil. Pitting failure was associated with the chilled white iron follower using the fully formulated oil under high load conditions. This failure could have been initiated by either a surface, sub-surface or stress - corrosion mechanism. Analysis of this type of failure is complicated by the difference in both chill depth and hardness and also the presence. of cracks within, samples prior to examination and testing. Standardisation of chilled white irons therefore needs to be carried out in order to understand fully the wear behaviour of such materials. Polishing wear was associated with the fully formulated oil at low loads, and appeared to occur by a chemical reaction between the contacting surfaces and the additives present in the oil. The use of the acetate replica technique proved a satisfactory method of analysing the change in surface topography of cam surfaces. Using the fully formulated oil the cam surface 'ran in' satisfactorily, by a process of plastic deformation and fracture, whilst the mineral base oil caused instanteous scuffing of the cam surface. Once the surfaces had 'run in' satisfactorily by using either the additives in the oil or by a diamond lapping operation, the cams continued to run without scuffing in the mineral base oil under continuous, non stop test conditions. An intermittent, stop/start operating cycle however results in eventual scuffing due to additive film depletion and repeated surface interaction under boundary lubrication conditions. From a range of 'new' materials tested for follower application the ceramics, with the exception of the toughened zirconia, exhibited the best wear characteristics using a case hardened steel cam as a standard and tested under mineral base oil conditions. The silicon carbide and sialon ceramics both exhibited a low frictional resistance and wear rate, whilst the metallic follower materials of cobalt and nickel base hard facing alloys and a ceramic fibre reinforced aluminium/silicon alloy all suffered some form of material.
9
Stephenson, Robin. "Analysing the dynamic loads in a high speed timing chain." Thesis, University of Newcastle Upon Tyne, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366783.
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10
Lancefield, T. M. "The application and effects of variable duration camshaft systems to light duty diesel engines." Thesis, University of Oxford, 2002. http://ora.ox.ac.uk/objects/uuid:b5efcd84-418e-451a-aa54-0b256881b22e.
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The work described in this thesis was carried out to investigate the application of variable valve actuation (VVA) to light-duty diesel engines for use in passenger vehicles. The background to this was that there was little published on the subject and with advanced turbochargers, exhaust gas re-circulation systems and high pressure fuel injection systems reaching maturity it seemed likely that further enhancement of the air management in this type of engine, through VVA would receive greater interest. The first section of this thesis discusses the external pressures on engine manufacturers, from legislation and from the customer expectations, which could be expected to influence the adoption of VVA, while looking at the criteria on which they would assess a VVA system prior to adoption. Section two provides an overview of the effects of VVA and how they may be used to improve engine operation by highlighting the specific features of diesel engines, i.e. cold starting and compression ratio, part load fuel economy, full load torque and transient torque rise, that can be influenced by air management and what characteristics are required from the VVA system in order to provide improvements in these areas. Having identified the key features of a VVA system that would be suitable for use in light duty diesel engines section three presents a brief literature review and discusses the family of non-constant angular velocity VVA systems that were identified as having the correct characteristics and relative simplicity necessary for any system that might be made in high volume production. This section also provides a detailed analysis of one system of this type to highlight its behaviour and impact on valve train design. Software was written to model the selected mechanism and produce the valve lift characteristics for use in simulating the engine's behaviour. Section four provides an overview of engine simulation techniques and some detail of the model constructed for this investigation. It also discusses the additional code and methodologies required to model the turbine, compressor and combustion processes, which required special treatment, and presents data to compare the behaviour of the model with the baseline of known engine behaviour. Section five presents simulation results that show the following possible improvements: a) a 23% increase in torque, b) light part-load fuel economy improvements of 13% and c) transient rise to maximum torque times reduced from 2.3 seconds to 1.6 seconds. It also discusses the features of engine operation with VVA that provide the potential for these improvements in engine operation, quantifies the benefits that might be expected at a large number of operating conditions and discusses the interactions between the VVA and other systems such as the turbo-charger and EGR system. Section six presents conclusions which beside the enumeration of the potential benefits and description of the key effects of VVA, highlights the need for test data to verify the extent to which the benefits can be realised in real engines and suggests areas for future research.
11
Lewandowski, David. "Experimental and Modeled Effects of Camshaft Manufacturing Errors on the Dynamics of High Speed Valve Trains." NCSU, 1998. http://www.lib.ncsu.edu/theses/available/etd-19981029-101808.
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AbstractLEWANDOWSKI, DAVID JOHN Experimental and Modeled Effects of CamshaftManufacturing Errors on the Dynamics of High Speed Valve Trains. (Under thedirection of Dr. Joseph W. David)The idea of harnessing combustion to perform mechanical work is by no means anew one. The internal combustion engine, as we know it today, has its origins in the lastcentury, however the idea for controlling combustion to perform mechanical work datesback to the Renaissance. Even with the advent of alternative sources of power forcommerce and personal applications, the internal combustion engine represents a largeportion of the power generation available in this country.There are numerous types of internal combustion engines, each with a variety ofsubsystems. While all of these types and corresponding subsystems are equally important,this investigation is focused on the valve train dynamics of a pushrod type internalcombustion engine. Operating this type of engine at too high of an engine speed usuallycauses dynamic malfunctions such as spring surge, lifter/cam pair separation, valvebounce, etc. in the valve train. Although the interaction of each of the valve traincomponents contributes to the limit speed, the shape of the cam plays a critical role.Therefore, this investigation will look at how small changes in the cam profile due tomanufacturing errors change the dynamics of a valve train in a pushrod type engine.Automotive cams can be manufactured as copied or original parts. Copied partsare typically produced on a rocker type cam grinder and the original parts are produced on a computer numerical control grinder. Therefore, various errors associated with thesemanufacturing techniques are studied herein.Installing cams with profile errors in an engine may result in the dynamicmalfunction of its valve train. In order to study the effect of these profile errors, some ofthe error cam profiles that were predicted for the rocker grinder were manufactured andtested in an actual valve train. In addition, the effects of error cam profiles wereinvestigated by using an existing valve train simulation model. It was found by bothexperimentation and simulation that camshaft errors on the order of typical shoptolerances had little impact on the dynamics of high speed valve trains.
12
Medonos, Michal. "Simulace zavedení nového výrobku do výroby." Master's thesis, Vysoká škola ekonomická v Praze, 2009. http://www.nusl.cz/ntk/nusl-17313.
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One of the products produced by Motorpal a.s. is a camshaft. Recently, the company signed a contract with Bosch company to produce new types of camshaft. The analysis of the impact of the contract on the production was made by simulation. To perform the simulation it was necessary to map the whole process. The simulation of the current state was made in the first phase. The results shew many uneffectivnesses in the process and lack of capacity of some workplaces. Some changes in the process were suggested and tested with the aid of the simulation. The best results were achieved when the single-item flow was used. In the second phase the production of a new type of camshaft was added to the simulation. Analysis of these results was divided into two parts. The new production was analysed in the first part and it was discovered that the planned capacites are very deficient. The impact of the new production on the current one was analysed in the second part. It shew that this impact is negativ, especially on the duration of production.
13
Moeller, Gregory V. "Residual stresses due to grinding." Thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-05022009-040807/.
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14
Cierocka, Joanna, and Jiayue Tang. "Vibrational tests of preloaded rubber vibration isolators : A cam controlled displacement excitation." Thesis, Linnéuniversitetet, Institutionen för maskinteknik (MT), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-53703.
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Vibrations are very common phenomenon. It influences structures and generates acoustic noise which might be harmful to human beings. The vibration isolator was invented to reduce the effect from vibrations. However, the behavior of rubber material, which many vibration isolators are made of, is hard to predict. Consequently, vibration tests are needed to obtain the dynamic properties of rubber isolator.In this case, a six-year old LORD 2204-5 rubber isolator provided by Atlas Copco was tested. The aim of this paper is to obtain the FRF (Frequency Response Function) diagram which can describe the property of the rubber material. Moreover, the influence of aging of rubber material on the dynamic properties was studied.As the vibration test should simulate the working environment of the isolators that are both a static load from the structure and a dynamic force from the engine, a new excitation method was designed. The camshaft with the shape of an epitrochoid induced the sinusoidal signal of the isolator and the frame transferred the static load from the hydraulic machine. The artificial aging was performed in a hot air oven in 90°C for 42 hours, which according to Arrhenius equation should be equivalent to six years of natural aging. The vibration isolator was tested again after being aged.The obtained data showed that the aging process decreased the stiffness of the material. The results were corresponding with other studies regarding aging of rubber.
15
Parker, Ian Kenneth. "Synchronous belt mechanics and life prediction : a fundamental investigation into the mechanics of toothed belts for automotive camshaft drives, and the prediction of belt life in operation." Thesis, University of Bradford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294351.
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Řehůřek, Lukáš. "Vliv pružnosti rozvodového mechanismu na pohyb ventilu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-254396.
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The aim of this thesis is a comparing single valve train motion (SVT) and complete valve train motion with a flexible camshaft focused on dynamic characteristics. In this thesis is also performed kinematics analysis in the VALKIN software. Dynamic analysis is solved in the MBS software Virtual Engine. Influences to the valve train motion are described in the conclusion
17
Uhlmann, Martin, and Florian Toste. "Simulation des dynamischen Verhaltens gebauter, wälzgelagerter Nockenwellen mit Mathcad." Universitätsbibliothek Chemnitz, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-142071.
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Im Vortrag wird die Vorgehensweise zur Modellierung des Ventiltriebs eines Einzylinder-Motorradmotors beschrieben. Dieser setzt sich aus zwei gebauten, wälzgelagerten Nockenwellen zusammen. Die Ventile werden über Schlepphebel betätigt. Das Hauptaugenmerk liegt dabei auf den Pressverbindungen zwischen Nocken und Welle sowie auf den Wälzlagerungen. Um die Belastungszustände zu ermitteln ist eine detaillierte Simulation nötig. Diese Mehrkörpersimulation wird in Mathcad mit Hilfe eines eigenen Lösers durchgeführt.
18
Štábl, Tomáš. "Návrh ventilového rozvodu pro zážehový motor." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2009. http://www.nusl.cz/ntk/nusl-228402.
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Tomáš ŠTÁBL Design of Gear Timing Mechanism for SI Engine MT, IAE, 2009, 62 pp., 27 fig. This master thesis is concerning the valve train proposal of the spark ignition engine for sports purposes. Antecedent to the actual proposal is the division and retrieval of the modern valve trains, the valve train acting forces description, division and description of the individual valve-lift curve parts , valve springs and the dynamic models of the valve train. In the thesis there are designed the valve lift curves with the continuous course of acceleration, valve springs and valve springs natural oscillations damper for engine Honda CBR 929RR. The dynamic analysis of valve train approach is performed.
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Tichý, Ondřej. "Koncepce řadového vstřikovacího čerpadla pro tlaky 120 MPa." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-254438.
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This thesis provides an overall evaluation of the concept of inline injection pump for pressure 120 MPa. The name of this pump is "Mj" and it is a product of the Motorpal, a.s. company. This thesis also contains an analysis of the contact pressures between the cam lobe and the pumping element's roller tappet. This includes comparing three different shapes of the roller and their influence on the magnitude of contact pressures. Calculations of the plunger helix and of the fuel delivery's impact on the relative position of plunger are also present.
20
Юрченко, А. М. "Проєкт вантажного автомобіля /комплексний проєкт/ з модернізацією паливної системи двигуна та розробкою технологічного процесу відновлення розподільчого вала." Thesis, Чернігів, 2021. http://ir.stu.cn.ua/123456789/23196.
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Юрченко, А. М. Проект вантажного автомобіля /комплексний проект/ з модернізацією паливної системи двигуна та розробкою технологічного процесу відновлення розподільчого вала : випускна кваліфікаційна робота : 274 «Автомобільний транспорт» / А. М. Юрченко ; керівник роботи Я. В. Кужельний ; НУ "Чернігівська політехніка", кафедра автомобільного транспорту та галузевого машинобудування. – Чернігів, 2021. – 128 с.Предметом даної магістерської роботи є розрахунок параметрів автомобіля та двигуна. Об’єктом дослідження магістерської роботи є модернізація паливної системи двигуна, з подальшим процесом відновлення відновлення розподільчого вала. Мета роботи – виконати розробку пристрою з подальшим налаштування для модернізації паливної системи двигуна, а також провести процес розробки технологічного процесу відновлення розподільчого вала. При виконанні магістерської роботи визначили: – визначили масові показники й параметри автомобіля, – провели розрахунок двигуна автомобіля, – показники динамічності автомобіля, – передавальні числа трансмісії – паливну економічність, – гальмівні властивості. У спеціальній частині магістерської роботи була проведена розробка пристрою з подальшим налаштування для модернізації паливної системи двигуна, та проведений процес відновлення відновлення розподільчого вала.
The subject of this master's thesis is the calculation of vehicle and engine parameters. The object of the master's thesis research is the modernization of the engine fuel system, followed by the process of restoring the camshaft restoration. The purpose of the work is to develop a device with subsequent configuration for upgrading the engine fuel system, as well as to develop the technological process for restoring the camshaft. When performing the master's thesis, we determined: - determined the mass indicators and parameters of the car, - we calculated the car's engine, - vehicle dynamism indicators, - transmission gear ratios - fuel efficiency, - braking properties. In the special part of the master's thesis, a device was developed with subsequent configuration for upgrading the engine fuel system, and the process of restoring the camshaft restoration was carried out.
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Guláš, Tomáš. "Dynamický výpočet rozvodu šestiválcového motoru s 24 ventily." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230479.
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Diploma thesis deals with the dynamic analysis of OHV pushrod valve train drive of the old-new conception of 6-cylinder tractor engine with 24 valves made by Zetor Tractors, a.s.. There is a requirement to create an analytical model and design valve springs for the engine. The work also points to the current analytical methods of appropriate simulation software used in automotive industry.
22
James, Jocelyn S. "The microstructural modelling of austempered ductile iron camshafts." Thesis, Loughborough University, 1999. https://dspace.lboro.ac.uk/2134/14359.
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Austempered ductile iron (AD!) is a material which is receiving increasing interest from the manufacturers of automotive components such as camshafts due to its superior mechanical properties, and in particular excellent wear resistance, compared with other grades of cast iron. ADI is produced from a spheroidal graphite casting using a two-stage heattreatment process. During the first stage of the heat-treatment the matrix is transformed to austenite, and then in the second austempering stage, some of the austenite is transformed to bainitic ferrite. The final microstructure is therefore complex, consisting of graphite, bainitic ferrite, austenite, carbides and possibly martensite. The major focus of this work has been to develop a novel method of predicting the effect of composition and heat-treatment parameters on the major constituents of the microstructure. This has resulted in a single model which can predict a 'microstructural map' of ADI and will assist the foundry industry in reducing lead times for component manufacture. The high temperature equilibrium between graphite and austenite was investigated using Gibbs free energy minimisation in conjunction with critically assessed thermodynamic data. Having established the carbon concentration in austenite at the start of the austempering process, the volume fraction of bainitic ferrite was established from prediction of the limiting carbon content for the diffusionless transformation. The kinetics of the bainite transformation were determined by making modifications to a model which was originally developed for low alloy steels. The predictions were compared with experimental data obtained, both during the course of this research and available in the literature, using dilatometric and X-ray diffraction techniques. The kinetics of the austenitisation were investigated through consideration of a diffusion couple between graphite and austenite. The degree of segregation and formation of primary carbides, in the original ductile iron casting, was calculated using a Scheil approach to solidification. The effect of this segregation was subsequently accounted for by making microstructural predictions on a number of individual 'shells' of material between two graphite nodules. Finally, complete microstructure predictions were compared with reported mechanical properties for a range of compositions and heat treatments of austempered ductile irons.
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Ferreira, Eduardo Prudente. "Estudo do comportamento tribológico em ferros fundidos nodulares austemperados para aplicações em eixo comando de válvulas." Universidade do Estado de Santa Catarina, 2012. http://tede.udesc.br/handle/handle/1630.
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In this present conducted in wear resistance nodular cast iron subjected to heat treatment at different temperatures isothermal austempering treatment (340 ° C and 320 °), corresponding to the materials of Classes 3 and 4 of ASTM A897, compared with nodular quenched and tempered with same level hardness. The objective was to develop alternatives for future studies on new materials applied camshaft valve internal combustion engines. For this wear tests were conducted pin-on-disc, using as alumina ball against the body, thus considering zero wear on the counter-body. All cast irons tested under the conditions of this work had hardness in the range 40-46 HRc. It was found in analyzes by scanning electron microscopy the effect of graphite nodules and the matrix material, the wear mechanisms, thus observing the effect that stress concentrator nodes imposes the metallic matrix. The damage to the material surface was initially with crack of the matrix surrounding graphite nodules, they generally located subsurface, moreover, it can be seen that the nodules torn metal matrix acted as a lubricant for testing, and the sites left by lumps were previously coated particles detached from the matrix. It was found with the results of wear tests the performance of austempered ductile iron in comparison with the quenched and tempered for distances exceeding 1000 m slip, thereby qualifying the ADI as an alternative material for future studies in manufacturing valve camshafts.
Apresenta-se neste trabalho um estudo de resistência ao desgaste realizado em ferros fundidos nodulares submetidos ao tratamento térmico de austêmpera em duas temperaturas isotérmicas de tratamento (340°C e 320°), correspondendo aos materiais das classes 3 e 4 da norma ASTM A897, comparativamente com o nodular temperado e revenido de nível de dureza similar. Objetivou-se desenvolver alternativas para estudos futuros em novos materiais aplicados a eixo comando de válvula de motores a combustão interna. Para isto foram realizados ensaios de desgaste pino-sobre-disco, utilizando como contra corpo esfera de alumina, considerando assim desgaste zero no contra-corpo. Todos os ferros fundidos ensaiados nas condições deste trabalho tiveram dureza na faixa de 40 46 HRc. Constatou-se em análises por microscopia eletrônica de varredura o efeito dos nódulos de grafita e da matriz do material, sobre os mecanismos de desgaste, observando assim o efeito concentrador de tensão que os nódulos impõe a matriz metálica. O dano à superfície do material ocorreu inicialmente com o tricamento da matriz em torno dos nódulos de grafita, estes geralmente localizados subsuperficialmente, além disto, pode se observar que os nódulos arrancados da matriz metálica atuaram como lubrificantes ao ensaio, e os sítios deixados pelos nódulos foram recobertos por partículas anteriormente desprendidas da matriz. Constatou-se com os resultados dos ensaios de desgaste o bom desempenho do ferro nodular austemperado em comparação com o temperado e revenido para distâncias de deslizamento superiores a 1000 m, qualificando assim o ADI como material alternativo para futuros estudos na fabricação de eixos comando de válvula.
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Östling, Johan. "High Accuracy Speed and Angular Position Detection by Dual Sensor." Thesis, Uppsala universitet, Fasta tillståndets fysik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-365726.
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For many decades there has been a need in many industries to measure speed and position of ferrous gears. This is commonly done by converting passing gear teeth from trigger wheels to electrical impulses to calculate speed and angular position. By using Hall effect sensors or Giant Magnetoresistance sensors (GMR), a zero speed detection of gear teeth is possible while at the same time be cheap to produce and durable for harsh environments. A specially designed trigger-wheel (cogwheel created for measurements) with gear teeth in a specific pattern, exact position can be detected by using a dual sensor, even when no earlier information is available. The new design of trigger-wheel also makes this new method more accurate and universal compared to previous solutions. This thesis demonstrates and argues for the advantages of using a dual sensor for speed and angular position detection on gear wheels. Were one sensor do quantitative measurements for pattern detection in the teeth arrangements and the other sensor do qualitative measurements for position detection.
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Астахова, Ксенія Вікторівна, Ксения Викторовна Астахова, and Kseniia V. Astakhova. "Удосконалення технології проектування і ремонту розподільних валів енергетичних установок тепловозів." Thesis, Видавництво УкрДАЗТу, м. Харків, 2012. http://eadnurt.diit.edu.ua:82/jspui/handle/123456789/1424.
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Астахова, К. В. Удосконалення технології проектування і ремонту розподільних валів енергетичних установок тепловозів : авт. дис. к. т. н.: 05.22.07 / К. В. Астахова ; Дніпропетр. нац. ун-т залізн. трансп. ім. акад. В. Лазаряна. - Д. : Вид-во УкрДАЗТу, 2012. - 20 с. : рис., табл. УДК 629.424.3:621.436(043.3) ГРНТИ 55.41.31 Захист - 21 лютого 2013 р.UA: АНОТАЦІЯ Дисертацію присвячено вирішенню актуального науково-практичного завдання з удосконалення технології проектування і ремонту розподільних валів енергетичних установок сучасних тепловозів за умов поліпшення їх техніко-економічних показників. В роботі проведено аналіз конструкції, функціонування та зношення енергетичних установок тепловозів, запропоновано блочно-ієрархічне описання конструкції ЕУТ з виділенням підсистеми розподільного валу, проаналізовано існуючі технології проектування та особливості ремонту розподільних валів енергетичних установок тепловозів. Формалізовано описання етапу профілювання газорозподільних кулачків удосконаленої технології проектування розподільних валів енергетичних установок тепловозів у вигляді задачі багатовимірної оптимізації з обмеженнями. У відповідності до запропонованого формалізованого описання розроблено новий патентозахищений метод профілювання високоефективних безударних кулачків. Для проведення перевірок виконання умов міцності та прийнятної динаміки запропоновано уточнені методи розрахунку кінематичних та динамічних характеристик просторових механізмів газорозподілу енергетичних установок тепловозів з дизелями Д49. На основі запропонованого нового методу профілювання газорозподільних кулачків проведено розрахунок координат профілів кулачків, відповідних кінематичних та динамічних характеристик. Пророблено технологію виготовлення і встановлення на розподільні вали нових патентозахищених безударних газорозподільних кулачків. Здійснено оцінку економічної ефективності впровадження запропонованих технічних рішень.
RU: АННОТАЦИЯ Диссертация посвящена решению актуального научно-практического задания по усовершенствованию технологии проектирования и ремонта распределительных валов энергетических установок современных тепловозов по условию улучшения их технико-экономических показателей. В работе проведен анализ особенностей конструкции, функционирования и износа распределительных валов энергетических установок тепловозов, предложено блочно-иерархическое описание конструкции энергетических установок тепловозов с выделением подсистемы распределительного вала, что позволило учесть межсистемные связи при решении задачи усовершенствования его конструкции. Проанализированы существующие технологии проектирования и особенности ремонта распределительных валов энергетических установок тепловозов. Формализовано описание этапа профилирования газораспределительных кулачков усовершенствованной технологии проектирования распределительных валов энергетических установок тепловозов в виде задачи многомерной оптимизации с ограничениями. Использование данной технологии и предложенных подходов к решению задачи позволяют решать задачи создания новых и модернизации существующих распределительных валов при условии улучшения показателей топливной экономичности и надежности энергетических установок тепловозов. В соответствии с предложенным формализованным описанием разработан новый патентозащищенный метод профилирования высокоэффективных безударных кулачков, особенностью которого является формирование и дальнейшее использование базовой кривой ускорений толкателя, которая в отличие от известных кривых учитывает не только заданные по требованиям рабочего процесса условия, но и установленные ограничения на изготовление и характеристики функционирования кулачкового механизма газораспределения. Для проведения проверок выполнения условия прочности и приемлемой динамики предложены уточненные методы расчета кинематических и динамических характеристик пространственных механизмов газораспределения энергетических установок тепловозов с дизелями Д49. На основе предложенного нового метода профилирования газораспределительных кулачков проведен расчет координат профилей кулачков, соответствующих кинематических и динамических характеристик, анализ которых подтвердил достижение высоких значений времени-сечения впускных и выпускных клапанов и понижение динамических нагрузок в КМГР ЭУТ Д49 при использовании на распределительном валу новых безударных газораспределительных кулачков. Проработана технология изготовления и установки на распределительные валы новых патентозащищенных безударных газораспределительных кулачков. Выполнена оценка экономической эффективности внедрения предложенных технических решений.
EN: THE SUMMARY Thesis are dedicated to the solution of issue scientific and practical problem of the improvement of the design technology and repair of camshafts modern diesel power plants providing improved conditions of their technical and economic performance. The analysis of design features, performance and wear camshaft diesel power plants, block-hierarchical description of the construction of power plants is carried out, emitting locomotives subsystem camshaft. Existing design technology and features of repair camshaft diesel power plants are analyzed. The description of the gas distribution segment profiling cams with the advanced technology design of the camshaft diesel power plants in the form of a multidimensional optimization problem with contingencies is formalized. New patented method of profiling high unstressed cams is developed in line with the formalized description. Refined methods of calculation of the kinematic and dynamic characteristics of spatial timing of power plants with diesel locomotives D49 are proposed with aim of verification of the condition and acceptable strength speakers. Based on the proposed new method of gas distribution cam profiling coordinates of cam profile corresponding to the kinematic and dynamic characteristics are calculated. The technology of production and installation of new camshafts patented unstressed gas distribution cams are worked out. Economic efficiency of the proposed solutions is evaluated
Українська державна академія залізничного транспорту, Міністерство освіти і науки, молоді та спорту України
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Kusomoto, André Yoshimi, Vasconcelos Luis Edwardo Guarino de, Nelson Paiva Oliveira Leite, Cristina Monis Araújo Lopes, and Rogério Pirk. "Tracking Track Targets in External Store Separation Using Computer Vision." International Foundation for Telemetering, 2014. http://hdl.handle.net/10150/577476.
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ITC/USA 2014 Conference Proceedings / The Fiftieth Annual International Telemetering Conference and Technical Exhibition / October 20-23, 2014 / Town and Country Resort & Convention Center, San Diego, CAFlight tests and flight safety are tightly coupled. For a given experimental test flight, the main objective to be achieved is related to the test bed and crew integrity (i.e. Bring back the test bed in one piece). Furthermore, the aircraft operational safety (i.e. continued airworthiness) relies into the accuracy of gathered information, provided by the airborne Flight Test Instrumentation (FTI) system. Typically, the FTI system includes: a data acquisition system; a transmission system; a data recorder; multiple sensors and auxiliary equipment such as Global Navigation Satellite System (GNSS) Receiver. In a specific Flight Test Campaign (FTC), such as external stores separation FTC, the associated risk is high because the non-linear and unpredicted aerodynamics couplings between the released store and the aircraft structure (e.g. wings) could lead to a catastrophic collision condition. Typically, the setup for such FTC is a big technical challenge for the instrumentation group because the determination of six degrees of freedom (6Dof) trajectory of the release store becomes mandatory. Such information could be by the means of an optical tracking system that requires the integration of two or more hi-speed hi-resolution video cameras into FTI. Unfortunately, the FTI and the Real-Time Telemetry Link (RTL) limited bandwidth imposes several restrictions for the development and implementation of a real-time application to be used at the Ground Telemetry System (GTS) for the verification of the separation safety and the validation of the test point. This paper, presents the implementation of computer vision techniques and Camshift algorithm as an approach to tracking individual track targets on the store surface which can be perform onboard and in real time or near real time. The development of the algorithm is presented as well several experimental test results that use videos frames gathered from previous FTC executed by Instituto de Pesquisas e Ensaios em Voo (Flight Test and Research Institute - IPEV). Preliminary results present satisfactory performance.
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Manat, Namith N. "System for Tracking of Surgical Tools and Assessment of Surgical Skills Using Continuously Adaptive Mean Shift Methodology." VCU Scholars Compass, 2005. http://scholarscompass.vcu.edu/etd_retro/56.
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A tracking system that serves as a tool for tracking the movement of surgical instruments has been developed. The system tracks color markers on the surgical instruments. The Continuously Adaptive Mean Shift (CAMSHIFT) methodology was employed for tool tracking and a total distance traversed by the surgical instrument of interest was calculated. Two cameras were used to record the motion of the tool and the software developed was used to track the movement of markers on the tools over subsequent frames. The information thus derived from the two views of cameras was used to calculate the three dimensional coordinates of the location of the marker on the instrument and subsequently the distance traversed. MATLAB, which is a commercial software package, was used to implement the tool tracking algorithm and for developing the GUI (Graphic User Interface). Data was collected using Commercial off the shelf (COTS) camera hardware and processing was done on a 2.2 GHz, 512 MB RAM Intel Pentium 4 computer.
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Klvaňa, Marek. "Sledování vybraného objektu v dynamickém obraze." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-229705.
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The aim of this thesis is a description and implementation of algorithms of the tracked objects in the video feed. This thesis introduces Mean shift and Continuously adaptive mean shift algorithms which represent category based on kernel tracking. For construction of a model is used a threedimensional color histogram whose construction is described in this thesis as well. The achievements of described algorithms are compared in the testing images sequences and evaluated in details.
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Райський, Д. М. "Проєкт легкового автомобіля з дослідженям технологічного процесу відновлення шарніра рівних кутових швидкостей, відновлення розподільчого валу." Thesis, Чернігів, 2021. http://ir.stu.cn.ua/123456789/25317.
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Райський, Д. М. Проєкт легкового автомобіля з дослідженям технологічного процесу відновлення шарніра рівних кутових швидкостей, відновлення розподільчого валу : випускна кваліфікаційна робота : 274 "Автомобільний транспорт" / Д. М. Райський ; керівник роботи В. І. Кальченко ; НУ "Чернігівська політехніка", кафедра автомобільного транспорту та галузевого машинобудування. – Чернігів, 2021. – 153 с.В ході написання роботи магістра, було проведено аналіз схожих за конструкцію автомобілі, вибрав прототип ГАЗ 3110, виконав розрахунок потужності двигуна, вирахував передаточні числа коробки перемикання. Виконав тепловий розрахунок двигуна й креслення до нього з графіками. Визначив показники динамічності руху автомобіля при рівномірному та не рівномірному завантаженні. Розрахував витрату палива автомобіля на сто кілометрів шляху. В подальшій частині розрахував параметри гальмівної системи барабанного типу, виконав модернізацію системи та розрахував дискові гальма. Також одним із завдань було відновлення розподільчого валу, в укому я вибрав способи відновлення деталі, підібрав обладнання, розрахував припуски та час на обробку кожного з дефектів. Для виконання розрахунків та графічної частини використовувались такі спеціальні програми як: “Mathcad”, “Компас 3D”, “Paint”.
In the course of writing the master's thesis, an analysis of similar cars was made, he chose a prototype GAZ 3110, calculated the engine power, calculated the gear ratios of the gearbox. Performed thermal calculation of the engine and drawings to it with graphs. Determined the dynamics of the car with uniform and non-uniform loading. Calculated the fuel consumption of the car for a hundred kilometers. In the further part he calculated the parameters of the drum-type brake system, performed system modernization and calculated disc brakes. Also, one of the tasks was to restore the camshaft, in which I chose ways to restore the part, selected the equipment, calculated the allowances and time to process each of the defects. Special programs such as “Mathcad”, “Compass 3D”, “Paint” were used to perform calculations and graphics.
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Brunclík, Robert. "Automatická regulace velikosti písma podle vzdálenosti čtenáře." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-241995.
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The thesis deals with automatic control the font size by the distance from the reader. It includes theoretical acquaintance with the face detection and subsequent tracking of the detected area during the scene. Furthermore, there is a comparison of the tracking algorithms. Then the calculation of distance is decribed. It is based on the user’s calibration and based on the outcome occurs the font size is automatically corrected. There is also a description of a separate application Automatical controller of the text size, with the recommended settings of the program.
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Baglieri, Giulia. "Caratterizzazione a fatica con intaglio di acciai innovativi ultra-alto resistenziali." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.
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Lo scopo della presente ricerca è valutare l’idoneità dell’acciaio da utensili innovativo K890, prodotto da Böhler con metallurgia delle polveri, ad essere impiegato per la realizzazione di componenti motore di moto da corsa, quali alberi a camme e a gomiti, in sostituzione dell’acciaio da nitrurazione GKHW, prodotto da Aubert&Duval con processo ESR (Electro Slag Remelting). Lo studio è stato condotto a valle di una precedente sperimentazione condotta su provini non intagliati ed ha previsto l'esecuzione di prove di trazione e prove di fatica a flessione rotante con intaglio oltre a prove di durezza ed analisi microstrutturali e frattografiche.
Sono stati testati due lotti di acciaio K890, aventi durezza di 752 e 821 HV rispettivamente. Durante i test di fatica il lotto in K890 a durezza maggiore ha mostrato un limite di fatica con intaglio superiore al GKHW nitrurato. I risultati ottenuti sui due lotti di K890 sono stati impiegati per valutare l’applicabilità di relazioni empiriche per la stima del coefficiente di concentrazione a fatica delle tensioni ad acciai ultra-alto resistenziali. E’ emerso che le relazioni più tradizionali sovrastimano l’effetto dell’intaglio per questa tipologia di acciaio. A conclusione dello studio, considerando l'esito delle stesse prove condotte sull'acciaio GKHW nitrurato attualmente in uso, si può affermare che l'acciaio K890 è un possibile candidato per la produzione di alberi in ambito racing.
La disamina dei risultati sperimentali è preceduta da tre capitoli incentrati su un inquadramento teorico, derivanti da ricerche bibliografiche: il primo riporta un’introduzione al funzionamento ed alle caratteristiche degli alberi a camme e a gomiti; il secondo è relativo alle proprietà degli acciai da utensili tradizionali ed innovativi; infine il terzo riguarda una trattazione sul danneggiamento da fatica, con particolare riguardo all’effetto dell’intaglio ed alle caratteristiche del fenomeno negli acciai ultra-alto resistenziali.
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Gustafsson, Simon, and Andreas Persson. "Detecting small and fast objects using image processing techniques : A project study within sport analysis." Thesis, Jönköping University, JTH, Avdelningen för datateknik och informatik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-54343.
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This study has put three different object detecting techniques to the test. The goal was to investigate small and fast-moving objects to see which technique’s performance is most suitable within the sports of Padel. The study aims to cover and explain different affecting conditions that could cause better but also worse performance for small and fast object detection. The three techniques use different approaches for detecting one or multiple objects and could be a guideline for future object detection development. The proposed techniques utilize background histogram calculation, HSV masking with edge detection and DNN frameworks together with the COCO dataset. The process is tested through outdoor video footage across all techniques to generate data, which indicates that Canny edge detection is a prominent suggestion for further research given its high detection rate. However, YOLO shows excellent potential for multiple object detection at a very high confidence grade, which provides reliable and accurate detection of a targeted object. This study’s conclusion is that depending on what the end purpose aims to achieve, Canny and YOLO have potential for future small and fast object detection.
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Tokatli, Aykut. "3d Hand Tracking In Video Sequences." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606461/index.pdf.
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The use of hand gestures provides an attractive alternative to cumbersome interface devices such as keyboard, mouse, joystick, etc. Hand tracking has a great potential as a tool for better human-computer interaction by means of communication in a more natural and articulate way. This has motivated a very active research area concerned with computer vision-based analysis and interpretation of hand gestures and hand tracking.
In this study, a real-time hand tracking system is developed. Mainly, it is image-based hand tracking and based on 2D image information. For separation and identification of finger parts, coloured markers are used. In order to obtain 3D tracking, a stereo vision approach is used where third dimension is obtained by depth information. In order to see results in 3D, a 3D hand model is developed and Java 3D is used as the 3D environment.
Tracking is tested on two different types of camera: a cheap USB web camera and Sony FCB-IX47AP camera, connected to the Matrox Meteor frame grabber with a standard Intel Pentium based personal computer. Coding is done by Borland C++ Builder 6.0 and Intel Image Processing and Open Source Computer Vision (OpenCV) library are used as well. For both camera types, tracking is found to be robust and efficient where hand tracking at ~8 fps could be achieved.
Although the current progress is encouraging, further theoretical as well as computational advances are needed for this highly complex task of hand tracking.
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Song, Min-Hang, and 宋旻航. "Investigation of Geometric Characteristics for Camshaft Machining Using Turning and Milling Complex Machines." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/mazrj9.
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碩士國立屏東科技大學
機械工程系所
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This study mainly investigated the influence of each processing condition on workpiece concentricity, eccentricity and radius of curvature for machining single camshaft workpieces using turning and milling complex machines. The experiment was planned using the Taguchi orthogonal table, and the measurement results were analyzed, whereby we found the optimal processing conditions for camshaft machining using turning and milling complex machines. The processing conditions include spindle speed, feed rate, cutting distance, cutting depth, eccentric distance and so on. Following the processing experiment, the workpiece concentricity, eccentricity and radius of curvature were measured, with their variances analyzed respectively, which indicated the degree of influence of each processing condition. The results suggested that the optimal processing parameters for concentricity were an eccentricity of 14 mm, a cutting distance of 0.3 mm, a cutting depth of 2.5 mm, a rotational speed of 3000 rpm, and a feed rate of 700 mm/min, while those for eccentricity were a feed rate of 600 mm/min, a rotational speed of 3000 rpm, a cutting depth of 2.5 mm, an eccentricity of 12 mm, and a cutting distance of 0.4 mm. The parameters affecting radius of curvature were divided into two types. The optimal processing parameters for concentric curvature (R) were a cutting depth of 2.5 mm, an eccentricity of 12 mm, a rotational speed of 3000 rpm, a cutting distance of 0.3 mm, a feed rate of 700 mm/min, while those for eccentric curvature (r) were a cutting depth of 2.5 mm, a rotational speed of 2800 rpm, a feed rate of 500 mm/min, a cutting distance of 0.1 mm, and an eccentricity of 14 mm. The analysis results of optimal processing conditions in this study could serve as a reference for machining workpieces with different geometries using turning and milling complex machines, and could contribute to the precision machining field.
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Tsai, I.-Ta, and 蔡易達. "The design and improvement of the camshaft for driving intake valve of SI engine." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/21458549170845393797.
Full textAbstract:
碩士遠東技術學院
機械研究所
94
Intake efficiency is the most fundamental and important parameter for engine performance, yet the open and close timing as well as the lift depth of the intake valves are determined by the contour curve of the camshaft, that means the valve timing and lift depth are constant and fixed. With the rising of environment-consciousness and the economy costs concerns, the developments of high horse power and low fuel consumption engine are the ultimate goal for every car manufacturer. By understanding the development and function of the variable valve timing and lift, we realized that four-stroke engine can get much better volumetric efficiency by tuning open and close angles of the intake valves. This paper is based on the model of TOYOTA 1.8 Celica GT-S ,After re-modification, the Compound camshaft can change the contour curve of the camshaft, single-cam alone may have a varied close and open timing and lift depth, it’s a Compound camshaft with continuous variable valve timing and lift. Analysis and evaluation of this cam for its velocity and acceleration under different revolutions revealed the cam redesigned will trigger some mechanical drive problems, further modifications are still required. Based on the analysis, the continuous curve won’t cause jumping which has no difficulty analytically and pragmatically, the control system of this mechanism may well be used on the engine practically through experiments.
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Kianifar, Mohammed R., I. Felician Campean, and D. Richardson. "Evaluation of camshaft control strategies for a GCI engine using a multidisciplinary optimisation framework." 2014. http://hdl.handle.net/10454/10715.
Full textAbstract:
NoThis paper presents a calibration optimization study for a Gasoline Direct Injection engine based on a multidisciplinary design optimization (MDO) framework. The paper presents the experimental framework used for the GDI engine mapping, followed by an analysis of the calibration optimization problem. The merits of the MDO approach to calibration optimization are discussed in comparison with a conventional two-stage approach based on local trade-off optimization analysis, focused on a representative emissions drive cycle (NEDC) and limited part load engine operation. The benefits from using the MDO optimisation framework are further illustrated with a study of relative effectiveness of different camshaft timing control strategies (twin independent Versus fixed timing, exhaust only, inlet only and fixed overlap / dual equal) for the reference GDI engine based on the part load test data. The main conclusion is that the MDO structure offers an effective framework for the GDI steady state calibration optimization analysis.
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Childs, T. H. C., K. W. Dalgarno, Andrew J. Day, and R. B. Moore. "Automotive timing belt life laws and a user design guide." 1998. http://hdl.handle.net/10454/2376.
Full textAbstract:
The paper presents a computer-based guide of the effect of layout and loading (tension and
torque) on the timing belt life and uses it to show the sensitivity of life to changed conditions in an
automotive camshaft drive. The predictions are in line with experience. The guide requires belt property
information, such as the tooth and tension member stiffness, the friction coefficient between the belt lands
and pulleys and the pitch difference from the pulley, in order to calculate the tooth deflections caused by
the belt loadings on the various pulleys in the layout. It also requires information on how the belt life
depends on the tooth deflections. Experimental data are presented on the life±deflection relations of a
commercial automotive timing belt tested between 100 and 140 8C, although the bulk of the data has been
obtained at 120 8C. Four different life laws have been found, depending on whether the failure-initiating
deflection occurred on a driver or a driven pulley, and whether at entry to or exit from the pulley.
Theoretical analysis of the tooth loading in the partial meshing state shows that, in three cases out of the
four, the different life±deflection laws transform to a single relation between the life and the tooth root
strain. The exception is failure caused by driven entry conditions; work is continuing to understand better
the causes of failure in this circumstance
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Chou, Shu-Wei, and 周書暐. "A Modified CamShift Algorithm for Video Object Tracking." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/84382736893253456423.
Full textAbstract:
碩士銘傳大學
資訊傳播工程學系碩士班
102
Mean-shift algorithm is a popular and high efficient object tracking method. The CamShift is an adaptive version of Mean-Shift algorithm. It is able to adjust the size of object window automatically. CamShift employs the histogram of the tracking target to generate the probability map and then find new center accordingly. Camshift has wide attention for objet tracking because of its high efficiency and robustness. However, it is often distracted or interfered by the other larger objects with similar colors. This paper presents a novel tracking algorithm based on the Camshift framework, which uses the probability density image determined by the color feature. The proposed algorithm employs the probability density image derived from both color and virtual shape features. Experimental results indicate the proposed algorithm improves robustness without sacrificing computational cost, as compared to the conventional CamShift and Mean-Shift related algorithm.
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Chun-Ting, Lin. "Multi-CAMSHIFT for Multi-View Faces Tracking and Recognition." 2005. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-2407200517140600.
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Chien, Jui-Chen, and 簡瑞辰. "Accurate and Robust ROI Localization in CAMSHIFT Tracking Application." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/71918913979137437303.
Full textAbstract:
碩士淡江大學
資訊工程學系碩士班
100
In this paper, we present an improved version of CAMSHIFT algorithm. We use a 2D histogram including hue and brightness to describe the color feature of the target. In this way, videos with poor quality or achromatic points can be better characterized. The Flooding process and contribution evaluation are used to obtain a precise target histogram which reflects true color information and discrimination ability. To be adaptive to the foreground/background variation, formula for updating ROI size and target histogram are proposed. The proposed method is compared with existing methods and shows steady and satisfactory results.
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Lin, Chun-Ting, and 林俊廷. "Multi-CAMSHIFT for Multi-View Faces Tracking and Recognition." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/48101734259845767833.
Full textAbstract:
碩士國立臺灣大學
機械工程學研究所
93
This thesis, aims to develop a system for multiple objects tracking and multi-view faces detection and recognition. We propose a novel method (Multi-CAMSHIFT), which is based on the characteristics of color and shape probability distribution, to solve the tracking problems for multiple objects. The tracker is used to get the candidate regions by outlining the interested probability distribution. The system performance is further improved by using multi-resolution framework and computation reduction. The principal component analysis (PCA) and support vector machine (SVM) are integrated to form the multi-view faces detection and recognition module for classifying different face poses and identities. Beside color information, the gray background image is used to locate the human head in the region of tracking pedestrian based on probability distribution rule. The rule can also be used for skin color face tracking to remove background region (non-face region). Since the proposed Multi-CAMSHIFT (MCAMSHIFT) is computationally efficient, it can work in complex background and track in real-time. The slowly changing lighting condition is effectively resolved using probability model update. From experiments, the proposed MCAMSHIFT was successfully applied to multi-view faces tracking and recognition. It can also be applied to surveillance system, pedestrian tracking and face guard systems.
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JIAN, MU-JHE, and 簡睦哲. "Improved Camshift Algorithm for Tracking Objects in Complex Environments." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/xd7tq4.
Full textAbstract:
碩士國立宜蘭大學
電機工程學系碩士班
107
The main research in this paper is to improve the traditional algorithm of Camshift. In the traditional Camshift algorithm, the target can be tracked in a simple environment with high efficiency and high accuracy, and tracked according to the color probability distribution of the target, although in a simple environment. The tracking effect is good, but the environmental changes are always changing rapidly. In the process of tracking the target, if it occurs in a similar color background, the target is obscured by other obstacles, or the light changes, etc., the above problems may lead to the traditional The Camhsift algorithm failed to track, so these are the issues to be explored in this article. This paper proposes a method to improve the traditional Camshift, using background subtraction to improve the influence of similar color background, combining the Kalman filter to predict the position of the target behind the obstacle, and using the error value between the Camshift measurement and the Kalman filter prediction value to determine the correct position of the target. The occlusion of the light will also reduce the tracking effect of the target, and the light occlusion will also reduce the tracking effect of the target. Therefore, the average brightness is calculated around the target to compensate for the probability distribution of the bright and dark colors, and the fuzzy theory is used to achieve the instantaneous probability distribution of the main color of the traced histogram, and the improved Camshift is used to track the effect in complex environments.
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Lai, Yu-Chi, and 賴昱圻. "CamShift Based Multiple Human Tracking in Light Changing Environment." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/41262299973201577937.
Full textAbstract:
碩士國立交通大學
電控工程研究所
103
In this thesis, we implement an automatic human tracking system that combines face detection and upper outer garment tracking in the light changing environment. Face detection can detect each person in the screen; upper outer garment tracking can track each person’s location by upper outer garment’s color. We use Haar cascade classifier and skin color detection for human face detection, which can locate the human face region correctly. Then, relative position with respect to a face founded will be used to locate one’s body region, and in the sequel hue-saturation color histogram model for upper garment is generated. We use CamShift algorithm to track person’s position. For better accuracy, we check the light change for each image frame and rebuild color model to adapt to the large enough light change in the environment.
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Wang, Ting-Wei, and 汪廷瑋. "Dynamic Object Tracking based on CamShift and Kalman Filter." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/60735071047895855691.
Full textAbstract:
碩士中原大學
電機工程研究所
104
In the thesis project of object tracking, we propose the thesis combining the Cam Shift algorithm with Kalman filter which can provide the position of the target more accurately. The tracking algorithm of Cam Shift can only be used in simple background with few colors. By combining the Kalman filter, we can reduce the interference of the background color and make the tracking more accurate. In this thesis, we follow these steps: First, by converting our target image into the H.S.V. color space, we can get desired color information and adjust the contrast of the hue, saturation and brightness. Then we need an initial point to start our tracking process. The traditional Mean Shift theorem does not allow users to change its window size and may lose its target, so that we calculate the search window size and the position of the mass center based on the Cam Shift algorithm. The process is continued until the desired accuracy is met. Finally, due to the instability of the complex background, we add the Kalman filter to lower the noise and interference during the experiment. After the process, we can achieve higher accuracy. The experiments show that the Cam Shift algorithm with the Kalman filter can reduce the noise and instability much more effectively than using only the former. In this thesis, the contributions of the research are as follows: 1.Kalman filter improves and strengthens the stability of the Cam Shift algorithm execution in complex background. 2.It is difficult to detect the object with various colors using in Cam Shift algorithm. Combining it with the Kalman filter improves the object detection capability and make the result more precise. 3.The object tracking experiment helped us expand the measurement range from single color still object to dynamic background processing.
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Huang, Chun-lin, and 黃俊霖. "Design of Real-Time Object Tracking System Using CamShift Algorithm." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/08498874349723356589.
Full textAbstract:
碩士國立成功大學
工程科學系碩博士班
97
Vision was the most advanced sense of human, and it holds a very responsible sense for image capture. Computer techno is moving forward, the technical innovations in image process was maturity, but not completed. In convention, most image target detecting and tracking was based on build-in video camera. Unfortunately, it will inactive when the target out of the shoot. This thesis addressed one real-time target tracking system methodology for improving the tracking dead-zone. Whole system integrates embedded USB 2.0 engine 8051-based MCU, PAS6311LT CMOS image sensor, 3-dimensions DC motor driving controller and addressed image processing algorithm. In the hardware driving part, MCU captures the digital image data and passes through to computer via USB interface channel. Major image processing and tracking algorithm implementation was based on computer (includes Bayer pattern transfer, bilinear interpolation, Lam auto white balance, HSV color space analyze and CamShift algorithm, etc.) This thesis applies addressed methodology in a “Launching-Pads” module to verify the performance, from exprimental, addressed methodology is proved to work well and effective.
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Huang, Wen-Xing, and 黃文星. "Face Detection and Tracking Model Using Haar-Like Features and CamShift technigues." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/04489280973398836695.
Full textAbstract:
碩士國立勤益科技大學
資訊管理系
102
In more recent years, surveillance systems are widely installed in public area for only security monitoring. With the rapid development of digital technology, IOT (Internet of Things) concept is used in the field of the intelligent surveillance and has become more critical. The results of the video analysis are not only presented simple frames but also applied in human identity、vehicle safety driving and flow statistic. The information, features from the video analysis, can be applied to analyze environment security、flow changing and customer demand. The proposed model in the thesis, Haar-like features Detection and Tracking Model, is used to identify and track a human face with detection stage and tracking stage. In the detection stage, Haar-like features and HOG algorithm are used to extract features from video frames. The human face detector, generated from Adaboost algorithm and SVM classifier, is used to locate the position of a human face. After detection process, CamShift algorithm is used to track the trajectory of the human face with skin color. By using the skin color, the color distribution of a face can be found and is used to resize the candidate region for detecting and tracking a human face. The experimental results of this study show that the detection rate of the hybrid model, Haar-like、HOG and SVM, is 84%. The detection rate of HDTM model is 100%. Moreover, the proposed model, HDTM, can be applied in the dynamic object detection and the human face detection without loosing the region of the human face.
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Haung, Wei-Tao, and 黃韋韜. "Realization of Moving Platform Control for a Landing RotorCraft Based on Camshift Algorithm." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/z78r5d.
Full textAbstract:
碩士國立東華大學
電機工程學系
104
With the advance of autonomy technology, quadrotor crafts have found their applications in a variety of fields, including rescue-aid, military, entertainment, and secure monitoring etc. Among others, auto-landing is one of key technical issues for quadrotors. Unfortunately, landing with the aid of GPS unavoidably bring about error in accuracy. The thesis endeavor to develop an autonomous mobile platform to pick up the landing rotorcraft using image processing and visual servoing techniques. The autonomous platform is driven by omnidirectional wheels and can be used to resolve the landing accuracy problem and serve as a carrier for maintenance and recharging of quadrotors. The technical issues concerning the design of an autonomous platform consist mainly of image tracking of a quadrotor and motion control of the omnidirectional moving vehicle. The Camshift algorithm for image feature points was employed to capture the moving trajectory of a quadrotor and the sliding mode control was devised to fulfill tracking control of the omnidirectional moving platform along the trajectory. The visual servo control scheme features its robustness against parameter variation and output disturbances. The thesis implements the image tracking algorithm in a laptop computer using C# programming language and realizes the motion control law in an onboard micro control unit (MCU). The estimation of the image moving trajectory is sent from the laptop computer to the MCU via UART and the PWM control signals for motors are generated accordingly to drive the three omnidirectional wheels so that the moving platform is able to achieve tracking of the quadrotor.
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Liou, Yun-Jung, and 劉允中. "An Improved CamShift Algorithm Based on Adaptive Motion Estimation for Multiple Camera Systems." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/78721416340903036566.
Full textAbstract:
碩士淡江大學
電機工程學系碩士班
100
Smart video surveillance has been developed for a long time, and many approaches to track moving objects have been proposed in recent years. The research of good tracking algorithms becomes one of the main streams for the smart video surveillance research. Multiple moving object tracking is a fundamental task on smart video surveillance systems, because it provides a focus of attention for further investigation. Video surveillance using multiple cameras system has attracted increasing interest in recent years. Moving objects occlusion is a key operation using correspondence between multiple cameras for surveillance system. In this thesis, the current state-of-the-art in moving objects tracker for multiple cameras surveillance has been surveyed. An efficient modified adaptive CamShift structure is proposed to further reduce the computational cost and increase the object tracking information in occlusion image. In this work, a new CamShift approach, directional prediction for adaptive CamShift algorithm, is proposed to improve the tracking accuracy rate. According to the characteristic of the center-based motion vector distribution for the real-world video sequence, this thesis employs an adaptive pattern (ASP) search to refine the central area search. Furthermore for estimation in large motion situations, the strategy of the adaptive CamShift search can preserve good performance. Experimental results indicate that the accuracy rate of the adaptive CamShift algorithm is better than that of the CamShift algorithm. Furthermore, the proposed method has given an average accuracy rate of 90%, and the operation speed can reach 12 FPS with frame size of 320
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Chen, Bo-Chih, and 陳柏志. "Improving the Ability of Visual Tracking and Automatic Controlling on Robot by Applying Multi-CAMSHIFT." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/13662924912927946948.
Full textAbstract:
碩士國立中興大學
資訊科學與工程學系所
100
Object tracking is a kind of research widely used in image processing. It can be used in many cases, such as driving support system, monitoring, and robotic vision. In this thesis, we discuss how to adopt object tracking to robotic vision. We modify CAMSHIFT algorithm and apply it to a robot to do self-tracking on the specific object. In order to make it more successful on the robot, we use some techniques of image processing for robustness, and use multi-CAMSHIFT algorithm to recover from the failure of tracking, which makes it find the target object which CAMSHIFT algorithm missed. We use LEGO NXT bricks to construct a car-shaped robot, and combine it with a webcam. We write programs to control the robot and let it drive automatically. It will automatically decide to do which kind of movement depends on the images that webcam captured. Our contributions mainly focus on using multi-CAMSHIFT algorithm to find the missing target object, and on making the robot re-tracking to improve the robustness of application.
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Chain-AnWu and 吳健安. "Design for the Torque Minimization of Engine Camshafts and Dynamic Analysis of a Timing Chain System." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/c6972w.
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