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Identificação e simulações do comportamento do pneu visando a implementação de controle em cadeiras de rodas motorizadas / Identification and simulation of tire parameters aiming to implementation of control in electric wheelchairSilva, Ludmila Corrêa Alkmin e 17 August 2018 (has links)
Orientador: Franco Giuseppe Dedini / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-17T17:46:09Z (GMT). No. of bitstreams: 1
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Previous issue date: 2011 / Resumo: Neste trabalho foi estudada a modelagem do contato roda-piso e a teoria de controle de uma cadeira de rodas. Logo, para complementar os testes e estudos, foi desenvolvido um laboratório virtual objetivando o estudo da dinâmica veicular e da modelagem do contato roda-piso. Esse laboratório, criado em programas multicorpos como o Working Model 2D ® e o MSC Adams?, foi usado para a visualização do comportamento dinâmico de uma cadeira de rodas em diversas situações. Nesta aplicação, observa-se que as características dos pneus são alguns dos parâmetros mais importantes da modelagem do contato roda-piso de um veículo. Deste modo, para a obtenção desses parâmetros foi construída uma bancada experimental. Esta bancada experimental é constituída basicamente de uma mesa fixada por células de cargas e uma estrutura onde a roda é presa. Vários testes experimentais foram propostos e os parâmetros, ou seja, as características do pneu foram levantados, implementados e comparados entre si, através de imagens e gráficos. Para o estudo da teoria de controle, foi construído um protótipo funcional de uma cadeira de rodas motorizada no qual o principal objetivo é seguir uma linha desenhada no chão. A utilização de sensores, microcontroladores e estratégias de controle foram necessárias a fim de atingir este alvo. Diferentes tipos de controle robusto foram simulados levando em consideração as características do pneu e o controlador PID foi implementado no protótipo funcional apresentando resultado satisfatórios ao seguir uma trilha desenhada no chão / Abstract: In this work was studied the model of the contact between the tire and the ground and the control theory of a wheelchair. Thus, for the tests and studies was developed a virtual laboratory for the dynamic vehicle and the contact between tire and ground model. This laboratory was created in a multibody program as Working Model 2D® and MSC Adams®, also was used to visualize the dynamic behavior of a wheelchair in various situations. The characteristics of tires are the most important parameters of the contact between ground and tire, so for that an experimental device was built. This test rig consists basically of a table fixed by the load cells and a structure where the wheel is attached. Several experimental tests have been proposed and the parameters or the characteristics of a tire were investigated, compared and implemented with each other by images and graphs. For the control theory was built a prototype of a electric wheelchair in which the main objective is to follow a path drawn on the floor. For this goal was necessary to use sensors, microcontrollers and control strategies as a PID / Doutorado / Mecanica dos Sólidos e Projeto Mecanico / Doutor em Engenharia Mecânica
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Utilização da radiação ionizante na reciclagem de pneus inservíveis de automóvel e sua destinação ambiental adequada / Use of ionizing radiation in the recycling of unserviceable tires of automotive and its adequate environmental disposalSOUZA, CLECIA de M. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:42:28Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:02:09Z (GMT). No. of bitstreams: 0 / O objetivo deste trabalho foi utilizar a radiação ionizante na reciclagem de pneus inservíveis de automóvel. As amostras de borracha de pneus inservíveis foram irradiadas com doses de radiação de 200, 400 e 600kGy, em um acelerador de elétrons. Posteriormente, elas foram caracterizadas por termogravimetria (TG), calorimetria exploratória diferencial (DSC), ensaios mecânicos de tração, espectrofotometria de infravermelho por transformada de Fourier (FTIR) e microscopia eletrônica de varredura (MEV). Por TG foi possível observar os efeitos da radiação na perda de massa do material. Por DSC observou-se as curvas exotérmicas associadas à decomposição e valores de variação de entalpia (ΔH). Foram estudadas as propriedades mecânicas das amostras da matriz elastomérica com o pó de pneu inservível e verificado o seu comportamento frente à radiação ionizante. Os espectros FTIR foram obtidos na região de 4000 650cm-1. Observou-se que não foi possível observar alteração nos picos devido à irradiação. Nos ensaios por MEV as micrografias foram ampliadas de 32 vezes até 1000 vezes e observadas nos tamanhos de 1mm até 20μm. Observou-se nas doses de 200 e 400kGy, rugosidades correspondentes a quebras ou rupturas, possivelmente causadas pela radiação. Na dose de 600kGy, foi possível observar cavidades causadas pela radiação. Observou-se que para todas as doses houve degradação. Para as amostras dos corpos de prova sem pó e com pó de pneus inservíveis com 10%, 30% e 50% de pó as micrografias foram observadas nas ampliações de 100μm e 200μm. Também foi possível observar a incorporação do pó de pneus inservíveis de automóvel na matriz elastomérica das amostras não irradiadas e irradiadas. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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Resíduos de poli (tereftalato de etileno) e de pneu na confecção de pisos flutuantes para o isolamento do ruído de impacto / Poly (ethylene-terephthalate) and tyre residues in floating floors for impact sound insulationCARVALHO, Maria Luiza de Ulhoa 21 August 2009 (has links)
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Previous issue date: 2009-08-21 / The demographic growth has created a gain in urban solid waste that deteriorates the citizen s
quality of life. High buildings represent the main way for accommodations in big cities for
these growing urban populations. However, impact sound insulation has shown itself quite
poor. In order to propose an alternative way of minimization to the two problems, residue
generation and impact noise, this study aimed to investigate the viability of using poly
(ethylene-terephthalate) - PET and rubber tire residues for impact sound insulation in floating
floors. Plates of 1 m² with thickness of 1.5 and 2.5 cm to 1:4 and 1:5 (ciment:residue) ratios
were molded for the acoustic experiments, as well as portable mortar slabs covered with high
and popular quality floor coverings. The main methods used were ISO 140-7 (1998) for
measuring the standardized impact sound pressure level, L nT, in one-third-octave bands and
ISO 717-2 (1996) to calculate the weighted standardized impact sound pressure level, L nT,w.
Both residues presented high sound insulation in relation to their references. It was observed
that the results for the PET specimen were superior to those of the rubber tires residue.
However, the results among the residues presented different tendencies as their ratio changed.
While the impact sound insulation of the rubber tires samples decreased with the increase of
residue, PET samples presented more insulation with residue increase. Another observed
factor was that the high quality floor covering presented a significant superior impact sound
isolation compared to the popular floor covering. Considering all results, it is possible to
conclude that the use of the studied residues in floating floors contributes to impact sound
insulation / O crescimento demográfico mundial tem criado um aumento na geração de resíduos sólidos
urbanos e deteriorado a qualidade de vida dos cidadãos. As edificações altas se apresentam
como a principal forma de acomodação da crescente população nas cidades, no entanto, o
conforto sonoro em relação ao ruído de impacto tem se mostrado precário. Com o intuito de
propor uma alternativa de minimizar ambos os problemas, a geração de resíduos e o ruído de
impacto, a presente pesquisa teve como principal objetivo estudar a viabilidade de uso dos
resíduos de poli (tereftalato de etileno) - PET e do pneu inservível na confecção de pisos
flutuantes no isolamento do ruído de impacto. Placas de 1 m² com traço 1:4 e 1:5
(cimento:resíduo) nas espessuras de 1,5 e 2,5 cm foram moldadas para realizar os ensaios
acústicos, assim como placas de argamassa armada revestida com cerâmica popular e de alto
padrão. As principais metodologias utilizadas foram a ISO 140-7 (1998) para obter o nível de
pressão sonora de impacto padronizada por bandas de terças de oitavas, L nT, e a ISO 717-2
para ponderar o valor único do nível de pressão sonora de impacto padronizado e ponderado,
L nT,w. Ambos resíduos apresentaram isolamento superior em relação às respectivas
referências. Observou-se que o isolamento do ruído de impacto das amostras com PET foi
superior às com pneu. No entanto, os resultados entre os resíduos apresentaram tendências
diferentes com a mudança do traço. Enquanto que o isolamento das amostras do pneu decaiu
com o acréscimo do resíduo, as amostras com PET tiveram um ganho maior com o aumento
do resíduo. Outro fator observado foi que o contrapiso com cerâmica de alto padrão
apresentou um efeito significativo do isolamento em relação à cerâmica popular. Em vista de
todos os resultados pode se concluir que é viável a utilização dos resíduos estudados na
confecção de pisos flutuantes para o isolamento do ruído de impacto
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Neuartige Warmmahltechnologie zum Recycling von Elastomeren und Analyse prozessbedingter Eigenschaften / Novel milling technology for the recycling of elastomers and analysis of process-related propertiesHoyer, Stefan 15 February 2018 (has links) (PDF)
Die Arbeit widmet sich der Problemstellung der Substitution des Primärrohstoffes Kautschuk durch Rezyklate in Form von Gummimehl. Die für das innerbetriebliche Recycling von Kleinchargen technischer Elastomere hier eigens konzipierte und umgesetzte Warmmahltechnologie dient zur Herstellung von Gummimehlrezyklat hoher Qualität aus Lkw-Altreifen. Hinsichtlich ausgewählter Verarbeitungs- und Materialkennwerte von Mischung und Vulkanisat werden die Auswirkungen der Zugabe von Rezyklaten und die wesentlichen Einflussgrößen des den Rezyklaten zugrunde liegenden Aufbereitungsprozesses – das Kryogenmahlverfahren bzw. die neu entwickelte Warmmahltechnologie – herausgearbeitet. Abschließend erfolgt die Formulierung materialspezifischer Versagensmechanismen, die das entsprechende Aufbereitungsverfahren der Rezyklate berücksichtigen. / The work is devoted to the problem of the substitution of the primary raw material rubber by recycled materials in the form of rubber powders. For the in-plant recycling of small batches of technical elastomers an ambient grind technology was specifically designed and implemented for making rubber powders of high quality out of used truck tires. In terms of selected processing and material characteristics of the mixture and the vulcanizate the influences of the addition of recycled material and the significant factors affecting the regeneration process underlying these recyclates – the cryogenic grinding versus the new developed ambient grinding technology – were worked out. Finally, the material-specific failure mechanisms were formulated, incorporating the regeneration process of such regenerated materials.
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ANÁLISE MECÂNICA E QUÍMICA DE PLACAS PRÉ-MOLDADAS DE CONCRETO COM ADIÇÃO DE RESÍDUOS DE BORRACHA DE PNEUS / MECHANICAL ANALYSIS IS CHEMICAL OF PLATES PREMOLDED OF CONCRETE WITH ADDITION OF RESIDUES OF TIRESKroth, Leandro Agostinho 28 September 2012 (has links)
This work aims to analyze a building system that utilizes alternative material and residues of tire rubber in community housing. Primarily, this work shows a review of literature concerning housing, debit, environment, habitation projects in Brazil and recycling of used tires. Definitions, classification, types, models of technology and factors involving pré-fabricated comunits houses are also presented. In addition, characteristics of the Sistema Construtivo Bom-Plac are shown with detailed information of materials employed. Subsequently, measurements, probes and tests using concrete pre-cast slabs which with tire rubber are analyzed concerning moisture content, density, compressive strength and chemical analysis of the tire rubber. A better compressive strength reaching 14,38 MPa level was observed for mixture composition 1:2:0.5:2 (cement CP-V, sand, rubber and gravel number 1). To make sure that no heavy metals are released in the environment according to NBR 10006 of ABNT technical regulations chemical analysis were performed. Chemical analyses included tests evaluating water effect, solvability, pH, scanning electron microscopy, microbiology and water uses with and without sulfuric acid (H2SO4) and sodium hydroxide (NaOH). A brief report with experiences by the author are presented including the pré-fabricated type, habitation type, multi-functional septic tank and drainage are included in this thesis. / Este trabalho objetiva analisar um sistema construtivo com material alternativo, resíduos de borracha de pneus, em habitações de interesse social. A revisão bibliográfica apresenta pesquisa sobre habitação, déficit, meio ambiente, projetos habitacionais no Brasil, pneus e estudos do Sistema Construtivo Bom-Plac, compreendendo definições, classificações, tipologias, modelos de tecnologias, fatores intervenientes na construção civil. São apresentadas as características do Sistema Construtivo BOM-PLAC, com descrição dos materiais e componentes. São realizados medições, ensaios e testes utilizando-se corpos-de-prova de concreto com incorporação de resíduo de borracha, avaliando-se a umidade, massa unitária, granulometria, resistência à compressão e análise química do resíduo de borracha. O traço 1:2:0,5:2 (cimento CP-V, areia, borracha e brita nº 1) resultou em uma maior resistência média à compressão atingindo 14,38 MPa. A análise química, compreendendo os ensaios de lixiviação, solubilização, ph, microscopia eletrônica de varredura, difratômetro de raio-X, teste microbiológico e os ensaios com soluções de ácido sulfúrico (H2SO4) e soda cáustica (NaOH), mostraram que não há liberações de metais pesados para o meio ambiente, conforme a NBR 10006 da ABNT. Apresenta-se também um breve relato sobre experiências desenvolvidas pelo autor, propondo tipologia para placa, tipologia habitacional, fossa séptica multifuncional e sumidouro.
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Simplified Model for Rubber Friction to Study the Effect of Direct and Indirect DMA Test ResultsKelly, Michael J. 09 August 2021 (has links)
No description available.
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Detekce nápravy v systému vážení za jízdy / Axle detection in the weighing vehicle systemMičulka, Martin January 2021 (has links)
This master's thesis deals with the Weight in Motion systems (WIM). The main goal is to create simulation software that detects dual tires assembly with respect to the angle with which the sensor is embedded into the road. Thesis also contains literature search of available solutions of weighing systems and the sensors which are used in these systems. Subsequently, the thesis contains software for recognizing simple assembly or dual tires assembly from real measured data. Software solutions were developed using programming language Python v3.7. All source codes were developed in PyCharm Community Edition 2020.
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Studium vlivu požárů skládek komunálních a průmyslových odpadů na kontaminaci životního prostředí, produkty hoření pryže a halogenovaných polymerů / Study of the influence of fires of municipal and industrial waste landfills on the enviromental contamination, the combustion products of rubber and halogenated polymersSikora, Henryk January 2014 (has links)
This thesis deals with the issue of fires of municipal and industrial wastes, particularly of rubber and halogenated polymers. When these materials burn, significant amount of harmful substances liberate into environmental compartments. Analysis of samples subjected to thermal decomposition in laboratory conditions explored formation of characteristic compounds in dependence on conditions of combustion. Samples of air, water and soil taken from real fires that occurred between the years 2007 – 2011 in the region of Western Bohemia monitored spreading of these substances into the environment. Majority of these samples were analysed by the means of gas chromatography with mass spectrometric detection. Additionally the effect of extinguishing methods and use of fire extinguishers on formation and spreading of combustion products was studied, especially in soil and in water sources.
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Analýza vlivu rotace kola na aerodynamické vlastnosti vozidla / Analysis of the effect of rotation of the wheels on the aerodynamic characteristics of the vehicleŠkrášek, Roman January 2016 (has links)
This diploma thesis deals with modeling and CFD calculation of aerodynamic characteristics of vehicle, influenced by loaded or unloaded tires and boundary conditions applied on this tires. These calculations are combined with three types of variable rear body shape of DrivAer vehicle. There is a complete analysis and evaluation of the effects of these factors.
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Vapothermolyse des pneus usagés. Valorisation du noir de carbone récupéré, relation procédé-produit / Steam water thermolysis of used tires. Valorization of recovered carbon black, process-product relationshipMoulin, Ludovic 14 December 2018 (has links)
Selon la European Tyre Recycling Association (ETRA), plus de 3 millions de tonnes de pneus en fin de vie sont à traiter en Europe chaque année et sont directement concernés par les mesures législatives visant le réemploi et la valorisation de 95 % de la masse totale des véhicules hors d'usage. Malgré les différentes possibilités de valorisation des pneus usagés (applications dans le secteur du bâtiment et travaux publics, valorisation matière, valorisation énergétique), une partie du gisement français n’est pas répertorié, ni valorisé, et aucune des voies citées auparavant ne s’intéresse à la récupération du noir de carbone, qui est un constituant essentiel du pneu. Ce produit, à forte valeur ajoutée, est principalement utilisé comme charge de renfort dans l'industrie du caoutchouc et des plastiques. Il existe deux types de procédés thermiques industrialisés permettant de récupérer le noir de carbone d’un pneumatique en fin de vie : la pyrolyse et la vapo-thermolyse. La vapo-thermolyse, actuellement industrialisée par Alpha Recyclage Franche Comté (ARFC), est une variante innovante de la pyrolyse, qui utilise la vapeur d’eau surchauffée à pression atmosphérique. La solution qui consiste à substituer un noir de carbone issu d’un procédé de fabrication conventionnel par un noir de carbone issu de vapo-thermolyse de pneus repose sur la qualité du noir de carbone récupéré et, en particulier, sur ses propriétés physico-chimiques intrinsèques et de surface. L'objectif de ce travail de thèse est de proposer et mettre en place une méthodologie adéquate afin de récupérer et caractériser les propriétés physico-chimiques du noir de carbone recupéré (rCB) par vapo-thermolyse à partir d'une formulation de pneu, d'évaluer l'impact des conditions de fonctionnement du procédé sur les propriétés du rCB, et enfin de valoriser le rCB en tant que charge de renfort alternative pour l'élaboration d'un produit final. / According to the European Tyre Recycling Association (ETRA), more than 3 millions tonnes of waste tires are to be treated in Europe each year and are subject to legislation and regulation policies for the re-use and recycling of 95 % of the total mass of end-of-life vehicles. Despite the various opportunities for recycling used tires (civil engineering applications, material recovery, energy recovery), a part of the French available resource remains unvalued and none of the applications just mentioned focuses specifically on the recovery of carbon black, which is one of the main component of a tire. This high added value product is mainly used as reinforcing filler in the rubber and plastics industries. There are two types of industrialized thermal processes for recovering the carbon black from an end-of-life tire : pyrolysis and steam thermolysis. Steam thermolysis, currently industrialized by Alpha Recyclage Franche Comté (ARFC), is an efficient pyrolysis alternative which uses superheated steam at atmospheric pressure. The substitution of carbon blacks produced from a conventional manufacturing process by carbon blacks recovered from the steam thermolysis treatment is based upon the quality of the recycled product, especially regarding its physicochemical properties (intrinsic and surface). The objective of this work is to propose and implement an adequate methodology to recover and characterize the physicochemical properties of recovered carbon black (rCB) from steam thermolysis of a tire, to assess the impact of the process operating conditions on the properties of the rCB, and finally to valorize the rCB as an alternative reinforcing filler for the elaboration of a final product.
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