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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Arquitetura com sistema pré-fabricado modular volumétrico : modelo generetivo e diretrizes de fixação

Teribele, Alessandra January 2016 (has links)
A arquitetura pré-fabricada apresenta vantagens provenientes da industrialização, mas sua produção pode levar à repetição e padronização, gerando edifícios excessivamente similares. Constituem desafios importantes, para a personalização da edificação produzida através de Sistemas Pré-Fabricados Modulares Volumétricos, a combinação de módulos unidos, na sua maioria, por vértices coincidentes. Considerando que soluções compositivas alternativas implicam na diversificação de posição da junção entre módulos, o objetivo deste trabalho é especificar um modelo generativo que ofereça múltiplas alternativas compositivas vinculadas às diretrizes de junção. O desenvolvimento do modelo considerou, separadamente, três tipos de prisma: retangular, trapezoidal e triangular. Explorando seus componentes estruturais – pilar, viga e conexões -, extraiu-se, a partir dos padrões compositivos gerados, os tipos de encontro necessários para vincular tais componentes. Quatro conjuntos conectivos genéricos foram usados na simulação das junções e definição das diretrizes conectivas. O paradigma da Gramática de Formas associado aos tipos de encontro necessários para criar vínculos entre os componentes estruturais permitiu gerar, automaticamente, alternativas compositivas. O uso do modelo confirmou que, alternativas compositivas com unidades volumétricas tridimensionais, dependem simultaneamente de atributos geométricos e construtivos do conjunto conectivo usado para fixar os módulos entre si. Ao mesmo tempo, demonstrou que a variação compositiva pode ser ampliada através da exploração da relação compositiva-conectiva, respeitados os atributos conectivos e diferentes graus de ajustes nos conjuntos conectivos utilizados. / The prefab architecture has advantages from industrialization, but its production can lead to repetition and standardization, generating excessively similar buildings. They constitute important challenges for customizing the building produced by Prefabricated Volumetric Modular Systems that require combination of modules united mostly by coincident vertices. Whereas alternative compositional solutions imply the diversification position of the junction between modules, the objective of this work is to specify a generative model that offers multiple compositional alternatives linked to joint guidelines. The development of the model considered separately three types of prism: rectangular, trapezoidal and triangular. Exploring the structural components - pillar, beam and connections - it is extracted from the generated compositional standards, types of meeting necessary to link these components. Four generic connective sets were used in the simulation of the joints and connective guidelines. The paradigm of grammar of forms associated with the types of meeting needed to create links between the structural components enabled to generate, automatically, compositional alternatives. The model use confirmed that, compositional alternatives with threedimensional volumetric units depend simultaneously on geometric and constructive attributes of the connective assembly used to secure the modules together. At the same time it showed that the compositional variation could be enlarged through the exploration of the connective-compositional relationship, observing the connective attributes and different degrees of adjustment in connective sets used.
12

Arquitetura com sistema pré-fabricado modular volumétrico : modelo generetivo e diretrizes de fixação

Teribele, Alessandra January 2016 (has links)
A arquitetura pré-fabricada apresenta vantagens provenientes da industrialização, mas sua produção pode levar à repetição e padronização, gerando edifícios excessivamente similares. Constituem desafios importantes, para a personalização da edificação produzida através de Sistemas Pré-Fabricados Modulares Volumétricos, a combinação de módulos unidos, na sua maioria, por vértices coincidentes. Considerando que soluções compositivas alternativas implicam na diversificação de posição da junção entre módulos, o objetivo deste trabalho é especificar um modelo generativo que ofereça múltiplas alternativas compositivas vinculadas às diretrizes de junção. O desenvolvimento do modelo considerou, separadamente, três tipos de prisma: retangular, trapezoidal e triangular. Explorando seus componentes estruturais – pilar, viga e conexões -, extraiu-se, a partir dos padrões compositivos gerados, os tipos de encontro necessários para vincular tais componentes. Quatro conjuntos conectivos genéricos foram usados na simulação das junções e definição das diretrizes conectivas. O paradigma da Gramática de Formas associado aos tipos de encontro necessários para criar vínculos entre os componentes estruturais permitiu gerar, automaticamente, alternativas compositivas. O uso do modelo confirmou que, alternativas compositivas com unidades volumétricas tridimensionais, dependem simultaneamente de atributos geométricos e construtivos do conjunto conectivo usado para fixar os módulos entre si. Ao mesmo tempo, demonstrou que a variação compositiva pode ser ampliada através da exploração da relação compositiva-conectiva, respeitados os atributos conectivos e diferentes graus de ajustes nos conjuntos conectivos utilizados. / The prefab architecture has advantages from industrialization, but its production can lead to repetition and standardization, generating excessively similar buildings. They constitute important challenges for customizing the building produced by Prefabricated Volumetric Modular Systems that require combination of modules united mostly by coincident vertices. Whereas alternative compositional solutions imply the diversification position of the junction between modules, the objective of this work is to specify a generative model that offers multiple compositional alternatives linked to joint guidelines. The development of the model considered separately three types of prism: rectangular, trapezoidal and triangular. Exploring the structural components - pillar, beam and connections - it is extracted from the generated compositional standards, types of meeting necessary to link these components. Four generic connective sets were used in the simulation of the joints and connective guidelines. The paradigm of grammar of forms associated with the types of meeting needed to create links between the structural components enabled to generate, automatically, compositional alternatives. The model use confirmed that, compositional alternatives with threedimensional volumetric units depend simultaneously on geometric and constructive attributes of the connective assembly used to secure the modules together. At the same time it showed that the compositional variation could be enlarged through the exploration of the connective-compositional relationship, observing the connective attributes and different degrees of adjustment in connective sets used.
13

Redesign of a generic human limb pressure device – towards early diagnosis of pressure ulcer risk patients

Länne Rosenlund, Hanna January 2016 (has links)
This report is a Bachelor thesis in the field of product development and design. It includes a literature review in the field of pressure ulcers and diabetes as well as a design process. The writer of this report, Hanna Länne Rosenlund, is a Mechanical Engineering student at the School of Engineering at Jönköping University. The focus of the education lies within product development and design. Pressure ulcers are a growing health care problem due to an increase in the mean life expectancy as well as an increase in diabetes in the world population. Patients with artificial limbs are often victims of pressure ulcers due to prolonged pressures from the prosthetic sockets on already sensitive areas of the body. Research in the field of pressure-induced injuries is currently taking place at Jönköping University. Their knowledge in finite element modelling and orthopaedic engineering made the research project, PEOPLE, possible. PEOPLE is a collaboration project between the School of Engineering and the School of Health and Welfare at Jönköping University as well as three company partners. In the project they aim to develop a device that will apply pressure to a lower limb while a MR camera takes scans of the limb. The images are later analysed closely by use of the finite element model, which means that all the different tissue properties will be collected for a computer simulation. In that way the tissues reactions to more extreme forms of pressure can be evaluated. This will contribute to the research in hope of eventually being able to predict whether or not a person might be at risk of developing pressure ulcers. A design of the prototype’s chassis was needed to optimize ease of use for both patient and staff, user options to expand research abilities, and sustainability. The design process includes product decomposition, concept generation, conceptual design, brainstorming, design for assembly, and design for component manufacturing, which generated several concepts. The final concept was decided by use of Pugh’s-matrices. The different concepts and the final concept were created in the computer aided design programme, Solid Works. The work resulted in a highly adjustable two-piece concept with optimized ease of use and sustainability due to the use of a Velcro strap. The prototype will come in two different sizes and will be mountable by a developed screwing system and therefore easy to pack, store and replace. It will also contain a new pressure relief system for a more comfortable patient experience. For further development of chassis of this kind, a replaceable pressure relief system would enhance the comfort when usage of larger limbs. When the device will be available for testing, a patient’s point of view can be taken in to consideration for a more reliable thesis and for further optimization of the comfort. / Detta är ett examensarbete på kandidatnivå inom ämnet produktutveckling och design. I arbetet ingår en litterär överblick och sammanfattning av forskning i ämnet angående trycksår och diabetes, samt en designprocess. Författaren, Hanna Länne Rosenlund studerar Maskinteknik med inriktning Produktutveckling och Design på Jönköpings Tekniska Högskola. Trycksår är ett växande problem inom vården på grund av en ökning i medellivslängden samt en ökning av diabetesdiagnoser hos världens befolkning. Patienter med proteser faller ofta offer för trycksår på grund av extrema och långvariga tryckförhållanden där proteserna är lokaliserade. Ett område som redan är känsligare för tryck. Forskning inom tryckframkallande skador pågår just nu på Jönköping University. Deras kunskap inom finita elements modellering samt ortopedingenjörsteknik har gjort detta forskningsprojekt möjligt. Forskningsprojektet heter PEOPLE och är ett samverkningsprojekt mellan Tekniska Högskolan, Hälsohögskolan samt tre företagspartners. Tillsammans siktar de mot att utveckla en prototyp som ska utsätta en lem för ett konstant tryck medan en MR kamera scannar vävnaden. En finit elements modell av lemmen skapas sedan för närmre granskning av vävnaden hos individen. Vävnadens egenskaper samlas sedan för en simulering då man kan utvärdera hur vävnaden skulle reagera på mer extrema former av tryck. På så sätt kan prototypen bidra till forskningen inom ämnet för att förhoppningsvis kunna förutspå ifall en person är vid risk för att utveckla trycksår eller inte. En omkonstruktion av prototypens chassi har utvecklats för att optimera användarvänligheten för både patient och personal, användarmöjligheten för forskningssyfte, samt för att bättre bidra till en mer hållbar lösning. Designprocessen har inkluderat teorier såsom produktnedbrytning, konceptgenerering, konceptutveckling, brainstorming, design for assembly och design for manufacturing som alla har hjälpt till att generera koncept. Det slutgiltiga konceptet valdes med hjälp av Pugh matriser. Koncepten samt det slutliga konceptet skapades i ett CAD (computer aided design) program, Solid Works. Arbetet resulterade i ett justerbart tvådelat koncept med optimerad användarvänlighet och hållbarhet genom att använda sig av ett kardborreband. Prototypen kommer att finnas i två olika storlekar och vara monterbar genom att det går att skruva bort chassit och på så sätt optimera packning, hantering och förvaring. Det kommer också att innehålla ett nyutvecklat system för att underlätta fördelningen av tryck på motsatt sida från indenteringen. För fortsatt utveckling av chassit hade ett utbytbart system för tryckavledning optimerat produkten ytterligare då komforten hade ökat vid användning på större lemmar. När produkten finns tillgänglig för testning i framtiden kommer en patients syn vara möjlig att ta med och på så sätt förstärka trovärdigheten av arbetet samt bidra till fortsatt strävande för komfort.
14

Desempenho de um ve?culo flex em bancada dinamom?trica de chassi

Laranja, Gil Colona 18 December 2010 (has links)
Made available in DSpace on 2014-12-17T14:58:06Z (GMT). No. of bitstreams: 1 GilCL_DISSERT.pdf: 1771464 bytes, checksum: 92ddc93639f74d5c2bbc96617815f7ed (MD5) Previous issue date: 2010-12-18 / Flex-fuel vehicles are equipped with Otto Cycle internal combustion engines and have the capability of functioning with more than one type of fuel, mixed at the same tank and burned in the combustion chamber simultaneously. This sort of motorization is a world pattern due to the scarcity of petroleum, the trade of several types of fuels, technology advances and the restriction imposed to gas emissions to the atmosphere. In Brazil, the Flexfuel vehicles are a reality, specially the ones using fuel with 20 to 25% anhydrous alcohol mixed with gasoline and those that use natural gas or original liquid fuel (gasoline or hydrated ethanol). The Brazilian model Fiat Siena, the object of this present scientific investigation, is equipped with a unique electronic central capable of managing the liquid or gaseous fuels. The purpose of this research was to perform a comparative analysis in terms of performance (in terms of both potency and consumption) of a tetra-fuel vehicle - using a chassis dynamometer, operating with different fuels: common gasoline, premium gasoline, Podium gasoline, ethanol or natural gas. It became necessary to develop a bench of tests and trials procedures, as well as to know the functioning of the electronic management of the vehicle under analysis. The experiments were performed at the automotive laboratory in CTGAS-ER (Center of Gas Technologies and Renewable energies) at the light of Brazilian standard ABNT, NBR 7024: Light on-road vehicles - measurement of fuel consumption. The essay results on specific fuel consumption using common gasoline, premium gasoline and Podium gasoline have shown similar results, both for urban and road driving cycles / Os ve?culos flex s?o equipados com um motor de combust?o interna do ciclo Otto e t?m como caracter?stica a capacidade de funcionar com mais de um tipo de combust?vel, misturados no mesmo tanque e queimados na c?mara de combust?o simultaneamente. Este tipo de motoriza??o ? uma tend?ncia mundial devido ? escassez do petr?leo, a comercializa??o de v?rios tipos de combust?veis, aos avan?os tecnol?gicos dos sistemas de gerenciamento eletr?nico de combust?vel e ?s restri??es as emiss?es de gases poluentes na atmosfera. No Brasil, os ve?culos flex s?o uma realidade, com destaque para os ve?culos alimentados com 20 a 25% do ?lcool anidro misturado com gasolina e os que utilizam g?s natural ou o combust?vel l?quido original (gasolina ou etanol hidratado). O FIAT SIENA TETRAFUEL, objeto da presente investiga??o, ? equipado com uma ?nica central eletr?nica capaz de gerenciar os combust?veis l?quidos ou gasoso. A pesquisa em tela teve como prop?sito a an?lise comparativa de desempenho (pot?ncia e consumo) de um ve?culo tetracombust?vel simulando ciclos de condu??o urbano e de estrada em um dinam?metro de chassi, operando com os combust?veis: gasolina comum (tipo C), gasolina aditivada (tipo C), gasolina Podium (Premium), etanol (AEHC) ou g?s natural (GNV). Foi necess?rio desenvolver bancada de testes e procedimentos de ensaios, como tamb?m conhecer o funcionamento do gerenciamento eletr?nico do ve?culo em quest?o. Os ensaios foram realizados no Laborat?rio do Centro de Tecnologias do G?s e Energias Renov?veis de acordo com a norma ABNT NBR 7024 - Ve?culos rodovi?rios leves Medi??o do consumo de combust?vel. Os resultados dos ensaios de consumo espec?fico com as gasolinas comum, aditivada e Podium resultaram em valores pr?ximos, tanto no ciclo de condu??o urbano como tamb?m no ciclo de condu??o de estrada
15

Análise estrutural estática por elementos finitos de um chassi veicular tipo spaceframe / Structural analiysis by static finite elements of a vehicular chassis type spaceframe

Pereira, Clezidan Núcio 25 August 2016 (has links)
Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2017-03-20T11:44:08Z No. of bitstreams: 2 Dissertação - Clezidan Núcio Pereira - 2016.pdf: 15290209 bytes, checksum: d8d29db8f1bebf00177f3f9d2ffda3d6 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-03-20T13:56:14Z (GMT) No. of bitstreams: 2 Dissertação - Clezidan Núcio Pereira - 2016.pdf: 15290209 bytes, checksum: d8d29db8f1bebf00177f3f9d2ffda3d6 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-03-20T13:56:15Z (GMT). No. of bitstreams: 2 Dissertação - Clezidan Núcio Pereira - 2016.pdf: 15290209 bytes, checksum: d8d29db8f1bebf00177f3f9d2ffda3d6 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-08-25 / Regarded as the main subsystem of a vehicle, the chassis are the link between the other subsystems and must also support multiple static and dynamic loads with stiffness, reliability and security. In this line, this paper presents the development and analysis of a vehicle three-dimensional structure spaceframe type, due to the complexity of the structure were used computational tooling in order to simulate the behavior of statically tubular structure, with the main objective to certify the reliability of the developed project, ensuring safety to drivers. The structure, existing, was modeled in CAD through SOLIDWORKS software, and their simulations were performed using the finite element method via commercial software ANSYS®. The simulationmethodology had the precise definition of loads and displacement constraints to the model in order to make the most plausible model possible. Were then performed computational analysis of rollover and frontal impact in the model (80 km/h e 60 km/h). Through the simulations, it was possible analyze the displacements arising from the critical situations in which the vehicle was submitted are consistent with what is recommended by regulating rules and bibliographies, with this in view that the chassis developed empirically and computationally simulated showed satisfactory results as its reliability and safety, are not required increment bars or modifying the system geometry. / Tido como o principal subsistema de um veículo, os chassis são o elo entre os demais subsistemas e ainda devem suportar diversos carregamentos estáticos e dinâmicos com rigidez, confiabilidade e segurança. Nesta linha, o presente trabalho apresenta o desenvolvimento e análise de uma estrutura veicular tridimensional do tipo spaceframe, na qual, devido a complexidade da estrutura foram utilizados ferramentais computacionais no intuito de simular estaticamente o comportamento da estrutura tubular, com o objetivo principal de certificar a confiabilidade do projeto desenvolvido, garantindo a segurança aos condutores. A estrutura, já existente, foi então modelada em CAD, através do software SOLIDWORKS, e suas simulações foram realizadas através do método de elementos finitos via o software comercial ANSYS®. A metodologia de simulação contou com a definição precisa dos carregamentos e restrições de deslocamento impostas ao modelo, a fim de tornar o modelo o mais verossímil possível. Foram então realizadas análises computacionais de capotamento e impacto frontal no modelo (80 km/h e 60 km/h). Através das simulações realizadas, fora possível analisar, que os deslocamentos oriundos das situações críticas na qual o veículo foi submetido, estão condizentes com o que se recomenda por normas regulamentadoras e bibliografias pertinentes, com isso, tendo em vista que o chassi desenvolvido empiricamente e simulado computacionalmente revelou resultados satisfatórios quanto sua confiabilidade e segurança, não são necessárias incremento de barras ou modificação da geometria do sistema.
16

Chassi- och hjälpramsinfästningar : utredning och analys av flexibla fästen på lastbil / Chassis and subframe brackets : investigation and analysis of flexible brackets on trucks

Malmrud, Johan January 2020 (has links)
Lastbilar som har en påbyggnation, såsom en tippbil, sopbil eller lastbil med kran, behöver ha en hjälpram fastsatt på sin chassiram för att kunna säkerställa lastbilens form och funktion. Dessa chassiramar och hjälpramar sätts ihop med olika typer av fästen. Generellt sett används stela fästen längre bak på ramen, samt flexibla fästen längre fram på ramen. Syftet med de flexibla fästena är att försöka få chassiramen att röra sig som en del av fordonets fjädringssystem, för att bland annat minska komfortstörande vibrationer. Examensarbetets syfte var att på uppdrag av Scania utreda dessa flexibla fästelement. Utifrån syftet formulerades tre huvudfrågeställningar. Den första var om det på ett analytiskt sätt gick att ta fram för- och nackdelar med de olika typer av flexibla fästelement som i nuläget används. Den andra frågeställningen var gällande åtdragningsmomentet på fästena. Skruven som sammanfogar fästet på chassiramen med fästet på hjälpramen sätts med ett väldigt lågt moment, för att undvika att fästet böjs sönder då de sätts med en glipa mellan varandra. Frågan var då hur kritiskt detta låga åtdragningsmoment var, och vad som händer om montören råkar dra åt lite för hårt. Slutligen så var den tredje frågeställningen hur mycket fästena kunde röra sig från varandra innan låsning uppkom, för att studera risken för att byrålådseffekt uppstår i fästet. För att få fram svar på dessa frågor gjordes det faktasökande i Scanias påbyggarhandbok, samt annan litteratur. För att öka förståelsen för Scanias fästen, utfördes intervjuer med personal från olika avdelningar. Det gjordes även FEM-analyser på ett vinkelfäste för att få ut spänningsbilder vid olika åtdragningsmoment. Gällande den första frågeställningen så gav faktasökande och intervjuer inte heltäckande information. Faktasökandet gav inte den sökta teoretiska bakgrunden. Intervjuerna gav en god överblick, men inte den detaljinformation som krävdes för att få ut ett adekvat resultat. Det är inte uteslutet att den detaljkunskapen finns på andra delar av Scania. Således rekommenderas vidare intervjuer och undersökning för att besvara frågan gällande inbördes för- och nackdelar mellan de flexibla fästelementen. Angående den andra frågeställningen, hur kritiskt åtdragningsmomentet var, gav FEM-analyserna spänningsbilder som visar att en viss felmarginal kan tillåtas, men inte mycket. Enligt Scanias monteringsanvisningar ska åtdragningsmomentet vara 25 Nm. Vid en ökning med 30 % på detta låga moment gick minsta säkerhetsfaktorn från 4 till 2,2. En oförsiktig montör kan nästan halvera minsta säkerhetsfaktorn i fästet. Dras däremot skruven mellan de båda vinkelfästena åt med samma moment som används för att fästa dem i ramen, 170 Nm, uppstår plastisk deformation och en vertikal förskjutning som förstör fästets flexibilitet. Angående den tredje frågeställningen, om låsning i fästet uppstår, löstes det geometriskt med hjälp av CAD-ritningar i CREO. Enligt anvisningar från Scania sätts fästena med ett lodrätt avstånd på 10 ± 5 mm mellan varandra. Detta gav två extremvärden, 5 mm samt 15 mm. Låsning uppstod fortare i fallet med 5 mm. Detta fall tillät en längsgående rörelse på 6,4 mm samt en rörelse på 5 mm i sidled innan en låsning uppstod i fästet. Det är många olika typer av dynamiska krafter som verkar på ramarna vid körning och användning av lastbilen, samt det är flera olika fästen på rad med varierande avstånd. På grund av dessa faktorer anses resultatet vara svårtolkat och således rekommenderas ytterligare utredningar samt experiment för att svara på om oönskad låsning och byrålådseffekt uppstår. / Trucks that have a superstructure, such as a dump truck, garbage truck or truck with a crane, need to have a subframe attached to their chassis frame, to be able to ensure the truck's shape and function. These chassis frames and subframes are assembled with different types of brackets. Generally, rigid brackets are used further back on the frame, as well as flexible brackets further forward on the frame. The purpose of these flexible mounts is to try to get the chassis frame to move as part of the vehicle's suspension system, to, among other things, reduce comfort-disturbing vibrations. The purpose of the thesis was to investigate these flexible mounts on behalf of Scania. Three main issues were formulated based on the purpose. The first was whether it was possible in an analytical way to identify advantages and disadvantages with the different types of flexible mounts that are currently used. The second issue was regarding the tightening torque on the brackets. The screw that joins the bracket on the chassis frame with the bracket on the subframe is set with a very low torque, to avoid the bracket being bent as they are inserted with a gap between each other. The question then was how critical this low tightening torque was, and what happens if the fitter happens to tighten a little too hard. Finally, the last question was how much the brackets could move apart before locking occurred, to study the risk of the drawer effect occurring in the bracket. To obtain answers to these questions, a fact-finding was made in Scania's bodybuilder instructions, as well as other literature. To gain an understanding of Scania's mounts, interviews were conducted with staff from various departments. FEM analysis were also performed on an angle bracket to obtain tension images at different tightening torques. Regarding the first question, fact-finding and interviews did not provide comprehensive information. The fact-finding did not provide the theoretical background that was sought after. The interviews provided a good overview, but not good enough detailed information to obtain an adequate result. It is not excluded that this detailed knowledge is available in other parts of Scania. Thus, further interviews and research is recommended to answer questions regarding advantages and disadvantages between the flexible mounts. Regarding the second question, how critical the tightening torque was, the FEM analysis provided tension images that show that a certain margin of error can be allowed, but not much. According to Scania's installation instructions, the tightening torque should be 25 Nm. With an increase of 30% at this low torque, the minimum safety factor went from 4 to 2.2. A careless fitter can almost halve the minimum safety factor in the bracket. If, on the other hand, the screw between the two angle brackets is tightened with the same torque used to fasten them to the frame, 170 Nm, plastic deformation and a vertical displacement occur which destroys the flexibility of the bracket. Regarding whether locking in the bracket occurs, it was solved geometrically with the help of CAD drawings in CREO. According to instructions from Scania, the brackets are placed at a vertical distance of 10 ± 5 mm between each other. This gave two extreme values, 5 mm and 15 mm. Locking occurred faster in the case of 5 mm. This case allowed a longitudinal movement of 6.4 mm and a lateral movement of 5 mm before a locking occurred in the bracket. There are many different types of dynamic forces that act on the frames when driving and using the truck, and there are several different mounts in a row with varying distances. Due to these factors, the results are considered difficult to interpret and thus further investigations and experiments are recommended to answer whether unwanted locking and the drawer effect occur.
17

Framtagning av ett chassi med upphängningssystem till en sexhjulig autonom leveransrobot / Development of a chassis with suspension system for a six-wheel autonomous delivery robot

Racho, Afram January 2022 (has links)
En växande medvetenhet om miljöfrågor i kombination med den ökade produktiviteten och effektiviteten som skapas av automation och digitalisering har lett till ett växande intresse för autonoma leveransrobotar. TerraGo Deliveries utvecklar eldrivna autonoma leveransrobotar med fokus på matleveranser. Målet med detta arbete är att ta fram ett chassi med ett upphängningssystem för en sexhjulig autonom leveransrobot där upphängningssystemet gör det möjligt för roboten att klättra över hinder på en max höjd av 10 cm. Programmet Granta EduPack 2022 R1 har använts för att söka ett lämpligt tillverkningsmaterial. Aluminiumlegering 6061-T6 har valts på grund av dess goda egenskaper. Creo Parametric 7.0.6.0 har använts för att designa chassit och upphängningssystemet. Creo parametric har också använts för att utföra alla statiska finita elementanalyserna (FEA) och dynamiska mekanismanalyserna. Programmet Ultimaker Cura 4.12.1 med 3D-skrivaren Ultimaker 2+ har använts för att skapa en förminskad prototyp för lösningsförslaget. Resultatet har blivit ett stegramschassi med en bågformad boggi som upphängningssystem som gör att roboten kan klättra upp och ned hindren. / A growing awareness of environmental issues in combination with the increased productivity and efficiency created by automation and digitization has led to a growing interest in autonomous delivery robots. TerraGo Deliveries develops electrically powered autonomous delivery robots with a focus on food deliveries. The goal of this work is to develop a chassis with a suspension system for a six-wheeled autonomous delivery robot where the suspension system makes it possible for the robot to climb over obstacles at a maximum height of 10 cm. The Granta EduPack 2022 R1 software has been used to search for suitable manufacturing material. Aluminum alloy 6061-T6 has been chosen because of its good properties. Creo Parametric 7.0.6.0 has been used to design the chassis and suspension system. Creo parametric has also been used to perform all static finite element analyses (FEA) and dynamic mechanism analyses. The Ultimaker Cura 4.12.1 software with the Ultimaker 2+ 3D printer has been used to create a scaled-down prototype of the designed system. The result has become a ladder frame chassis with an arched bogie as a suspension system that enables the robot to climb up and down obstacles.

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