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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.
51

Anatomie domu a digitální regionalismus / The House Anatomy and the Digital Regionalism

Boušková, Linda January 2018 (has links)
Robotics and digital design are associated with the creation of free forms. The thesis deals with the potential of new building technologies in the sense of an opportunity to build on the foregoing regional architecture, disconnected by an industrial mass production. A creation that can reinterpret the charm and diversity of Moravian houses, preserving the continuity between old morphology and today’s housing requirements.
52

Design, Development and Control of a Quadruped Robot

Fredriksson, Scott January 2021 (has links)
This thesis shows the development of a quadruped platform inspired by existing quadrupled robot designs. A robot by the name of Mjukost was designed, built, and tested. Mjukost uses 12 Dynamixel AX-12a smart servos and can extend its legs up to 19 cm with an operating height of 16 cm. All the custom parts in Mjukost are ether 3d printable or easy to manufacture, and the total estimated cost of Mjukost is around 900$. Mjukost has a simple control system that can position its body freely in 6 DOF using an inverse kinematic model and walk on flat ground using an open-loop walking algorithm. The performance experiments show that its slow control loopcauses difficulties for the robot to follow precise trajectories, but its still consistent in its motions.
53

Eletroforese com dupla detecção condutométrica sem contato e espectrometrica de massas / Electrophoresis with dual contactless conductometric detection and mass spectrometry

Francisco, Kelliton José Mendonça 03 October 2017 (has links)
A presente tese descreve o aprimoramento do acoplamento de eletroforese capilar/espectrometria de massas com ionização por electrospray (CE-ESI-MS) (1) pelo desenvolvimento de estratégias de controle de temperatura e posicionamento e (2) pela inclusão de dois detectores condutométricos sem contato (C4Ds) ao capilar de separação eletroforética de modo a se obter informações complementares àquelas fornecidas pelo MS. Os primeiros aprimoramentos consistiram na introdução de uma plataforma móvel para o CE e um módulo de refrigeração da porção externa do capilar. Com estes aprimoramentos, foi possível realizar estudo de cinética de hidrólise de monoetilcarbonato (MEC) por CE-ESI-MS, obtendo-se, pela primeira vez, o valor da energia de ativação de 99 ± 8 kJ mol-1. Posteriormente, foi desenvolvida uma série de protótipos de cartuchos impressos 3D em ABS, permitindo a introdução de até dois C4Ds. Além da inclusão dos detectores, a versão aprimorada do cartucho permitiu um bom comportamento térmico da coluna, permitindo que, tal como em sistemas CE-DAD, correntes eletroforéticas alcancem valores da ordem de 100 µA sem efeitos térmicos indesejados (o que não ocorre ao se utilizar o cartucho original para CE-MS). As possibilidades do arranjo CE-(C4D)2-ESI-MS foram demonstradas pelo desenvolvimento de métodos analíticos de separação para: (1) açúcares a pH 11,2; (2) aminas biogênicas a pH 2,0 e (3) ácidos carboxílicos a pH 7,5. A compatibilização dos eletroferogramas dos C4Ds ao longo do capilar e do ESI-MS no final do capilar foi conseguida pela correção da escala de tempo. Assim, as informações obtidas com os vários detectores podiam ser facilmente complementadas. Devido à baixa seletividade intrínseca do C4D, este se mostra amplamente complementar ao ESI-MS, que é o sistema mais seletivo para CE disponível na atualidade. Embora este último também seja altamente sensível, o C4D se mostrou comparável ou até mais apropriado em alguns casos. Assim, esta combinação única apresenta um grande potencial como ferramenta analítica. / The capillary electrophoresis/mass spectrometry with electrospray source (CE-ESI-MS) was improved by (1) the development of new temperature control and positioning systems and (2) the inclusion of two capacitively coupled contactless conductivity detectors (C4Ds) to the electrophoretic separation capillary allowing to obtain complimentary information to the MS. The initial improvements were the introduction of a sliding platform for the CE equipment and a thermostatic module for the portion of the capillary outside the CE environment. These improvements allowed obtaining, for the first time, the activation energy of hydrolysis reaction of monoethyl carbonate: 99 ± 8 kJ mol-1. However, the most important improvement was the development of 3D-printed cartridge allowing the inclusion of up to two C4Ds along the capillary. This cartridge also allowed a significant improvement of the thermal control over the capillary. No significant difference of the original CE-DAD was observed for electrophoretic currents up to 100 µA. The original CE-MS has similar behavior only until 60 µA. New possibilities of the CE-(C4D)2-ESI-MS setup were demonstrated by the development of analytical methods for separation of: (1) sugars at pH 11.2, (2) biogenic amines at pH 2.0, and (3) carboxylic acids at pH 7.5. The electropherograms of the three detectors were made compatible by correcting the time scales. Therefore, the information obtained from the three detectors may be easily complemented. Thanks to the intrinsic low-selectivity of the C4D, that is complementary to the MS, which is the most selective detector for CE today. Although MS is also highly sensitive, C4D had similar or even better performance in some cases. Therefore, this unique combination is powerful analytical tool
54

Desenvolvimento de uma técnica de desenho digital e impressão em 3D de placas oclusais e sua aplicabilidade no tratamento de pacientes com disfunção temporomandibular / Development of a technique of digital design and 3D printing of occlusal splints and its applicability in the treatment of patients with temporomandibular disorders

Vasques, Mayra Torres 11 December 2018 (has links)
O uso de novas tecnologias na odontologia, como a técnica CAD/CAM, promete ser uma opção relevante no que diz respeito à confecção das placas oclusais, empregadas no tratamento de disfunções temporomandibulares. O objetivo desta pesquisa foi desenvolver uma técnica para desenho e confecção de placas oclusais pelo método CAD/CAM, em impressora 3D, e verificar seus resultados clínicos no tratamento de pacientes com disfunções temporomandibulares. Para o desenho das placas foi desenvolvida uma metodologia de desenho digital (CAD), utilizando o software Meshmixer® (Autodesk, USA), e de registro das relações maxilo-mandibulares. A partir dessa metodologia iniciou-se um estudo clínico randomizado comparativo entre as placas CAD/CAM produzidas em impressora 3D e placas produzidas convencionalmente em laboratório. O estudo foi realizado em duas etapas, 18 pacientes foram avaliados de acordo com os critérios de inclusão e exclusão. Na Etapa 1 (n=18) foram realizados testes técnicos comparativos das duas placas em relação à dor, por meio da Escala Visual Analógica; atividade muscular; ajuste interno; báscula; conforto; tempo de instalação; pontos de contato oclusal. Todos os pacientes da amostra utilizaram os dois tipos de placas. Na Etapa 2, estes pacientes foram divididos randomicamente em dois grupos para o estudo clínico randomizado (estudo cego): Grupo IMP (n=9) (placas impressas) e grupo LAB (n=9) (placas convencionais laboratoriais). Os grupos foram avaliados após 1 mês de uso, por meio dos Questionários, RDC/TMD, SF-36, escala visual de dor EVA, e pelos pontos de contato oclusais. Os dados foram avaliados estatisticamente usando os testes de Wilcoxon, de Mann-Whitney, e de Kruskal-Wallis nas análises quantitativas; os testes Qui-Quadrado e Exato de Fisher, nas variáveis categóricas. Os resultados mostraram que houve diferenças significativas (P-valor<0.05) nas avaliações para conforto, ajuste interno e tempo de confecção das placas, a favor das placas impressas. Nas demais avaliações, os grupos foram equivalentes (não- significantes). Concluiu-se que foi possível desenvolver uma técnica para desenho e confecção de placas oclusais pelo método CAD/CAM, em impressora 3D, e que o desempenho clínico foi equivalente entre as placas convencionais e impressas, sendo que estas se mostraram superiores quanto ao conforto e quanto à adaptação da superfície interna da placa, mostrando ser este um método possível e viável economicamente. / The use of new technologies in dentistry, as the CAD/CAM technique, promises to be a relevant option concerning the manufacture of occlusal splints for temporomandibular disorders treatment. The aim of this research was to develop a technique for design and manufacture occlusal splints using the CAD/CAM method and 3D printer and verify the clinical results in the treatment of temporomandibular disorders patients. It was developed a technique for occlusal splint design a using the software Meshmixer® (Autodesk, USA) and a technique to register the jaws relationship. From this method, it was started a Randomized Clinical Trial (RCT) to compare splints made through the CAD/CAM technique and others made conventionally in a dental lab. The study was performed in two steps, 18 patients were selected based on the inclusion/exclusion criteria. In Step 1 (n=18) patients were comparatively evaluated, using both splints, in relation to pain, using the visual analog scale; internal adjustment of the splint; patients comfort; time spent to deliver the appliance and occlusal contacts pattern. In Step 2, these patients were allocated in two groups (n=9 each group) randomly to the RCT be performed (blind study): Group IMP - printed splints and Group LAB (conventional lab splints). Both groups were assessed after 1 month using the splint using RDC/TMD and SF-36 questionnaires, the visual analog scale for pain, and occlusal contacts pattern. The data were statistically evaluated using Wilcoxon, Mann-Whitney, and Kruskal-Wallis test for qualitative analyses and Qui-square and Fisher´s exact tests for categorical variables. The results showed significant statistical differences (p-value<0.05) in favor of printed occlusal splints, related to patients\' comfort, internal adjustment, and time spent to deliver the appliance. All other assessments were equivalents (not significant). It was concluded that it was possible to develop a technique to design and manufacture occlusal splints using CAD/CAM and 3D printer, and furthermore the clinical performance was equivalent comparing conventional and printed occlusal splints, being the printed splints superior to conventional splints in relation to comfort and internal adjustment, proving this is a possible and economically viable method.
55

Referensdesign av tryckknappar för bilinteriör : Förslag och koncept för framtidens tryckknappar / Reference design of push buttons in car interior

Eriksson, Martin, Stridkvist, Dennis January 2018 (has links)
This report presents a thesis done in the field of mechanical engineering with a focus on product development and design. The work was done together with Kongsberg Automotive AB in Mullsjö. The company wants to investigate the push button solutions available on the market today and the solutions that seem promising for the future. The purpose of this thesis is to examine what the user perceives as quality and define which solution the company should use in future products. To make the subject less about an abstract feeling of quality a method for interviewing end users was created. This allowed their feelings about good and bad characteristics to be concretized to statistical data about characteristics and buttons tested in the study. These statistics where then used in a product development process to create concepts from ideas. With support from an experienced professional a direction was set to create prototypes built around existing switches matching the results of the interview based study. The result is a number of concepts for solutions, as well as 3D-printed prototypes of the more promising solutions followed by advice on which direction future research in the area should be headed. The task was solved with several well documented methods such as Kano. With these methods, the market has been reviewed, user comments about quality have been collected and analyzed and new concepts has been created to accompany the coming trend and meet user demands.
56

Technické aspekty použití 3D tisku ve výuce na ZŠ / Technical aspects of the use of 3D printing in the education at elementary school

CVRČEK, Tomáš January 2016 (has links)
This thesis in the beginning deals with the history of 3D printing and its development. For better understanding the nature of 3D printing are the significant technologies that includes. Professional part includes work with the printer MakerBot Replicator 2X. Mechanical parts of the device are analyzed together with the operating software MakerBot DesktopThe following chapter is dealing with the limits and restrictions when it is printed on said 3D printer, except that describes important aspects when working on the printer. For the creation of electronic models are suggested appropriate programs for use in elementary school. A significant milestone is forming the problems of 3D printing, which can serve as a guide for the elimination of print quality problems, malfunctioning of 3D printers and others. Interesting models are designed for teaching physics and working activities that the students facilitate understanding of the substance of the response and act as activating element within lesson. It was created a list of important sites where you can find models suitable not only for teaching in elementary schools, but also for other purposes. The last chapter deals with the economic aspect of 3D printing.
57

Construction of Robot for Visual Demonstration at Conferences and Fairs

Haraldsson, Jonathan, Nordin, Julia January 2018 (has links)
A demonstration robot for conferences and fairs has been built from scratch. The demonstration robot is meant to create lasting impressions at the company booth at conferences or fairs. Thus, the robot needs traits that attract people to the booth and makes sure they remember that company. In this project, traits such as being able to move, do facial expressions and play audio have been developed. The robot has also been designed to draw as much attention as possible to the booth. This was achieved by building a robot that consists of a rolling sphere with a head that always remains on top. All movements are carried out from inside the sphere by four different motors. One motor moves the robot back and forth, two motors spin a flywheel to turn the robot and the last motor rotates the head. These motors are mounted at different places on an internal structure. The internal structure is connected to the sphere at two points, one on each side of the robot. At the top of the internal structure, magnets are placed. Thus, it can attach the head at the outside of the sphere by mounting magnets in the head. All movements of the robots are controlled by a hand controller, which has been made in this project. The head has a built-in display simulating two eyes. The display is driven by a Raspberry Pi. An internal speaker is built-in inside the head, connected to the Raspberry Pi. Each simulated eye consists of 64 squares that can be programmed to be in different colours, thus making it possible to express a wide range of facial expressions.Two PCBs were designed and manufactured to control the robot. One was placed inside the robot, and the other inside the hand controller. The PCBs can communicate over Bluetooth, which makes it possible to control the robot from the outside.All parts of the robot have been designed in a CAD program and subsequently 3D printed. 3D design in CAD was learned from a novice level, since there was no previous knowledge of this in the project group.In addition, a registration form has been developed that allows visitors to register at the booth. Making it easier for the company to connect with visitors after the conference or fair. The registration form is connected with the Raspberry Pi in the head of the robot via Wi-Fi. Thus, when new registrations occur, the robot can print the names of them while audio is played.
58

Eletroforese com dupla detecção condutométrica sem contato e espectrometrica de massas / Electrophoresis with dual contactless conductometric detection and mass spectrometry

Kelliton José Mendonça Francisco 03 October 2017 (has links)
A presente tese descreve o aprimoramento do acoplamento de eletroforese capilar/espectrometria de massas com ionização por electrospray (CE-ESI-MS) (1) pelo desenvolvimento de estratégias de controle de temperatura e posicionamento e (2) pela inclusão de dois detectores condutométricos sem contato (C4Ds) ao capilar de separação eletroforética de modo a se obter informações complementares àquelas fornecidas pelo MS. Os primeiros aprimoramentos consistiram na introdução de uma plataforma móvel para o CE e um módulo de refrigeração da porção externa do capilar. Com estes aprimoramentos, foi possível realizar estudo de cinética de hidrólise de monoetilcarbonato (MEC) por CE-ESI-MS, obtendo-se, pela primeira vez, o valor da energia de ativação de 99 ± 8 kJ mol-1. Posteriormente, foi desenvolvida uma série de protótipos de cartuchos impressos 3D em ABS, permitindo a introdução de até dois C4Ds. Além da inclusão dos detectores, a versão aprimorada do cartucho permitiu um bom comportamento térmico da coluna, permitindo que, tal como em sistemas CE-DAD, correntes eletroforéticas alcancem valores da ordem de 100 &#181;A sem efeitos térmicos indesejados (o que não ocorre ao se utilizar o cartucho original para CE-MS). As possibilidades do arranjo CE-(C4D)2-ESI-MS foram demonstradas pelo desenvolvimento de métodos analíticos de separação para: (1) açúcares a pH 11,2; (2) aminas biogênicas a pH 2,0 e (3) ácidos carboxílicos a pH 7,5. A compatibilização dos eletroferogramas dos C4Ds ao longo do capilar e do ESI-MS no final do capilar foi conseguida pela correção da escala de tempo. Assim, as informações obtidas com os vários detectores podiam ser facilmente complementadas. Devido à baixa seletividade intrínseca do C4D, este se mostra amplamente complementar ao ESI-MS, que é o sistema mais seletivo para CE disponível na atualidade. Embora este último também seja altamente sensível, o C4D se mostrou comparável ou até mais apropriado em alguns casos. Assim, esta combinação única apresenta um grande potencial como ferramenta analítica. / The capillary electrophoresis/mass spectrometry with electrospray source (CE-ESI-MS) was improved by (1) the development of new temperature control and positioning systems and (2) the inclusion of two capacitively coupled contactless conductivity detectors (C4Ds) to the electrophoretic separation capillary allowing to obtain complimentary information to the MS. The initial improvements were the introduction of a sliding platform for the CE equipment and a thermostatic module for the portion of the capillary outside the CE environment. These improvements allowed obtaining, for the first time, the activation energy of hydrolysis reaction of monoethyl carbonate: 99 ± 8 kJ mol-1. However, the most important improvement was the development of 3D-printed cartridge allowing the inclusion of up to two C4Ds along the capillary. This cartridge also allowed a significant improvement of the thermal control over the capillary. No significant difference of the original CE-DAD was observed for electrophoretic currents up to 100 &#181;A. The original CE-MS has similar behavior only until 60 &#181;A. New possibilities of the CE-(C4D)2-ESI-MS setup were demonstrated by the development of analytical methods for separation of: (1) sugars at pH 11.2, (2) biogenic amines at pH 2.0, and (3) carboxylic acids at pH 7.5. The electropherograms of the three detectors were made compatible by correcting the time scales. Therefore, the information obtained from the three detectors may be easily complemented. Thanks to the intrinsic low-selectivity of the C4D, that is complementary to the MS, which is the most selective detector for CE today. Although MS is also highly sensitive, C4D had similar or even better performance in some cases. Therefore, this unique combination is powerful analytical tool
59

Additiv tillverkning i metall och topologioptimering

Bousquet, Anna January 2017 (has links)
This thesis project was conducted as a case study at Scania CV, a manufacturer of trucks, buses and industrial and marine engines. The project aimed to investigate how topology optimization can be used to design end products for metal additive manufacturing (AM). The main research questions for the project was: How can topology optimization be used to design parts for metal additive manufacturing? Which gave rise to further research questions: Which parts are suitable for metal additive manufacturing? Which factors has to be considered when designing end products for metal additive manufacturing? The main benefits of additive manufacturing revealed in the literature were short lead time, possibility to manufacture complex geometries and consolidate multiple parts into a single part. The applications of metal additive manufacturing found in the literature included prototypes and end products as well as tools and spare parts. Small, complex geometries which are expensive to manufacture traditionally due to expensive tooling or low volumes are most likely to be suitable for metal additive manufacturing. Parts where trade-offs have to be made between manufacturing cost and performance could also be interesting to investigate for AM. The build size of the selected machine is a limiting factor when choosing parts and the build direction of the part, the need for support material during manufacturing and post processing are important to consider when designing parts for metal AM. The case study was performed based on Design for Additive Manufacturing (DFAM), a method for designing parts for AM. DFAM consists of deciding the specifications for the part, consolidate parts if possible, optimize the geometry of the part and make sure it is possible to manufacture. Two parts were optimized with topology optimization during the case study and the resulting geometries were imported to Catia in order to create CAD-models. The results from the case study showed it was possible to automatically create CAD-models based on the resulting geometries from topology optimization. However the automatic CAD-models are not suitable for manufacturing of end parts. But the case study indicates a weight reduction of about 30 % seems to be possible for topology optimization combined with AM even for parts already optimized for low weight but adapted for traditional manufacturing methods. Reducing the overall weight of trucks is important since the carrying capacity is important for customers when choosing vehicles for transportation and the gross vehicle weight is regulated by laws. This makes topology optimization and metal AM a highly interesting area for further investigation. As for now, small, complex parts which are traditionally expensive to manufacture are most likely to be profitable for manufacturing of end parts with metal AM. / Arbetet har utförts som en fallstudie på Scania CV som tillverkar lastbilar, bussar samt industri- och marinmotorer. Syftet med projektet var att undersöka hur topologioptimering kan användas för konstruktion av slutprodukter som ska tillverkas med additiv tillverkning (AM) i metall. Utifrån det togs tre frågeställningar fram som låg till grund för projektet. Huvudfrågeställningen var Hur kan topologioptimering användas vid konstruktion av artiklar för additiv tillverkning i metall? För att kunna svara på det krävdes mer kunskap om additiv tillverkning vilket ledde till följande två frågeställningar: Vilka produkter är lämpliga för additiv tillverkning i metall? samt Vilka faktorer behöver tas hänsyn till vid konstruktion för direkttillverkning av slutprodukter i metall med additiv tillverkning? De största fördelarna med additiv tillverkning som framkom i litteraturen var korta ledtider, möjlighet att tillverka komplexa geometrier och slå samman flera delar till en enda. Användningsområden för additiv tillverkning var allt från prototyper till serietillverkning samt tillverkning av verktyg och reservdelar.  De artiklar som är lämpliga att tillverka med AM är de som är dyra att tillverka traditionellt på grund av komplex geometri, dyra verktyg eller låga volymer. Men även artiklar som får ge avkall på funktion för att tillverkas eller har långa ledtider och höga lagerkostnader. Andra faktorer som är viktiga att tänka på är byggytans storlek för den maskin som ska användas samt vilken byggriktning som väljs, behovet av stödmaterial vid tillverkning och efterbearbetning av utskriven detalj. En fallstudie genomfördes baserat på Design for Additive Manufacturing som är en metod för att konstruera artiklar för AM. Metoden går ut på att bestämma vad komponenten ska ha för funktioner och prestanda, slå samman eventuella delkomponenter, optimera utformningen och sedan kontrollera att den är möjlig att tillverka. Under fallstudien undersöktes två fästen med topologioptimering och resultaten importerades till Catia för att skapa CAD-modeller. Resultatet påvisade att det är möjligt att skapa en automatisk CAD-modell i Catia utifrån resultatet från topologioptimeringen. Däremot blir resultatet inte tillräckligt bra för att i nuläget kunna använda den automatiska modellen för tillverkning av slutprodukter. Resultatet från fallstudien tyder dock på en viktminskningspotential runt 30 % även för redan lättviktsoptimerade artiklar anpassade för andra tillverkningstekniker vid anpassning till AM. Eftersom lastkapaciteten är en avgörande faktor för kundens val av fordon samt för att uppfylla gällande lagstiftning kring fordonets totalvikt och minska miljöpåverkan så är lättviktsoptimering av alla ingående komponenter ett viktigt utvecklingsområde. Därmed är även topologioptimering och AM intressant att undersöka vidare. För att AM i dagsläget ska vara lönsamt för tillverkning av slutprodukter rekommenderas i första hand små, geometriskt komplexa artiklar som är dyra att tillverka traditionellt på grund av exempelvis höga verktygs- eller bearbetningskostnader eller små volymer.
60

Assesment of Market Potential of 3D Body Scanners within the Target Group of 3D Print Stores / Assesment of Market Potential of 3D Body Scanners within the Target Group of 3D Print Stores

Martini, Julian January 2013 (has links)
The world has recently witnessed the widespread of 3D printing technology. In the shadow of this development a new means of freezing time was born: 3D figurines. A 3D figurine is a mini version of oneself; a little sculpture manufactured by 3D Printers. These 3D figurines are sold for a profit by so called 3D Print Stores to consumers. For the production of such a 3D figurine one needs 3D Body Scanners. It is from the perspective of a producer of 3D Body Scanners that this master thesis was written. The objective was to establish whether or not the company should tap into that new market segment of 3D Print Stores. Furthermore a market entry strategy was to be developed. Thus a marketing research study was performed. For the analysis of the market segment primary and secondary data was scrutinized, which was gathered through expert interviews and desktop research. The primary scope of the study was limited to Germany. Overall the market segment proved to be promising, as consumers regard 3D figurines as a more sophisticated alternative to a digital photo. Competition is currently low, but the threat of new players entering the segment is high. Thus a market entry strategy was elaborated that suggests tapping into the market as fast as possible; thereby obtaining a first mover advantage and pre-empting market space. Furthermore a differentiation strategy was proposed to shield against growing competition.

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