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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.
211

VYUŽITÍ 3D TECHNOLOGIÍ VE VEŘEJNÉM PROSTORU / THE USE OF 3D TECHNOLOGY IN THE PUBLIC SPACE

Šebánek, Jan Unknown Date (has links)
The aim of this thesis is to define the impact of rapid prototyping technology in terms of creative potential to use this technology represents a particularly sculpture and architecture. Rapid Prototyping is a generic term covering a range of technologies: 3D scan converting the already realistic three-dimensional objects in computer memory, parametric modeling, which creates three-dimensional objects based on the formative algorithms, photogrammetry method of compiling three-dimensional object from a photo, technology, 3D printing materializing after each layer objects transferred from the computer's memory. When processing the theoretical work will be explored and discussed possibilities for realization of basic three-dimensional objects using 3D technology. The second step will be to map the different methods of access to artists working with 3D technology. In the end it tried to evaluate the benefits of these technologies in the field of sculpture and architecture in terms of traditional approaches. This paper attempts to describe the possible implications and potential of this progressive field in the classical artistic disciplines such as sculpture and architecture, both in terms of benefits and in terms of the eventual negative impact with respect to increasing the availability of this technology.
212

Návrh a realizace výroby konstrukce zubní náhrady / Proposal and Implementation of Production of Dental Plate Construction

Dusbaba, Michal January 2016 (has links)
This thesis deals with a CAD programmed construction design of dental prosthetics and its subsequent production by means of a five axis machine tool. In the theoretical part of the thesis one can find characteristics and analysis of materials designed for a production of dental prosthetics constructions. Among other things, the practical part of the thesis follows up digitization of a patient´s oral cavity part with the use of Trios intraoral scanner representing the latest scanning technology. The obtained data created a basis for a design of the respective dental prosthetics construction using the shape dental system programme called DentalDesigner 2015. Furthermore, the paper deals with a production of a dental prosthetics construction by means of a five axis machine tool and pursues completion works which resulted in the prosthetics final shape. The paper is concluded with discussion comprising a summary of results acquired in the practical part beginning from dental implant introduction to insertion of the made prosthetics construction into the patient´s oral cavity.
213

BIM-modellering i tillverkningsindustrin : Framtagandet och utvärdering av en digital integreringsmodell av en CNC-maskin för mindre företag, med hjälp av terrester laserskanning

Eddelid, Pontus, Töyrä, Mikael January 2023 (has links)
Byggnadsinformationsmodellering (BIM) som begrepp har existerat i mer än 20 år och arbetssätt som innefattar BIM är fortfarande ett område i stark utveckling. BIM är ett arbetssätt som använder sig av digitala modeller med särskilt fokus på att knyta an- och dela information. En BIM-integrering medför en stor kostnad vilket har begränsat arbetssättet till de större företagen. Därav har det inte spridits till de mindre företagen i samma omfattning.  Denna fallstudie använde sig av en Trimble X12 och terrester laserskanning som metod för att utforska möjligheterna kring digital integrering hos ett mindre tillverkningsföretag. Detta skedde genom att skapa en nerskalad BIM-modell över en utvald CNC-maskin med dess tillbehör med hjälp av punktmoln och RGB-bilder i mjukvaran Autodesk Inventor. Datainsamling, utförandet och analys av punktmolnskvalitet genomfördes med hjälp av en kvantitativ process. RMS (Root Mean Square) beräknades genom att ta referensmått på CNC-maskinen med måttband för jämförelse med mått i punktmoln. Informationen till den nerskalade BIM-modellen utformades efter företagets behov. Med hjälp av semistrukturerade intervjuer hämtades information in gällande BIM och digitala tvillingar i form av tillvägagångsätt, metodutförande och utmaningar. Punktmolnet bearbetades i Autodesk ReCap för vidare modellering och hade ett medelöverlapp på 56 %, medelosäkerhet på 0,5 mm med ett RMS-värde på CNC-maskinens punktmoln på 6,5 mm. Terrester laserskanning visar sig vara otillräcklig för att noggrannt skanna in den utvalda CNC-maskinen, då den har flera reflektiva och mörka ytor. Detta förhindrar en låg osäkerhetsnivå. Studien föreslår därav andra möjliga alternativ som kan komplettera TLS för att förbättra punktmolnets kvalitet, men som kräver ytterliggare forskning. BIM-modellen berikades med information med hjälp av en ritningsfunktion i Autodesk Inventor i PDF-format. Ritningar presenteras i olika vyer tillsammans med informationstabeller och dimensionsmått efter företagets val av information. Ritningarna, BIM-modeller och arbetssätt utvärderades med företaget i fråga. BIM-modellen visade sig vara detaljmässigt överflödig för företagets intressen. Modellen tog två veckor att framarbeta, vilket anses vara för kostsamt för företaget i fråga. Men den information som modellen var berikad med gav positiva tankar kring framtida BIM-integrering i verksamheten, speciellt inom underhåll och komplettering av underlag för äldre och modifierade maskiner. Studien visar på att mer forskning kring digital integrering i mindre tillverkningsindustrier behövs. / Building information modeling (BIM) is a term that has existed for more than 20 years and is still developing. BIM utilizes enhanced digital models with attributes that focus on adding and sharing information. BIM is very costly to implement, limitingits use to mainly the larger companies. Thus, BIM has not been as widespread regarding smaller businesses. This case study explores the area of digital integration of a BIM-model of a CNC-machine in a smaller manufacturing company. With the aid of a Trimble X12 and terrestrial laser scanning, the study investigated the process of creating a scaled down BIM-model detailing a selected CNC-machine by using point clouds and RGB-images in the software Autodesk Inventor. The data collection, execution, and point cloud quality were analysed with a quantitative process along with RMS-calculations of measurements in the point cloud to reference measurements. The information assigned to the model was according to the company's needs. Using semi-structured interviews, the area of BIM and digital twins regarding the process, methods and challenges were discussed.  The point cloud was processed in Autodesk ReCap for further modeling and had an average overlap of 56 %, an average uncertainty of 0,5 mm with an RMS-value of the CNC-machines point cloud of 6,5 mm. Terrestrial laser scanning proved to be insufficient when it comes to scanning the CNC-machine, as it had multiple reflective and dark surfaces, which prevented a low level of uncertainty. Thus this study proposes several other techniques that can be combined with TLS to improve the point cloud quality, which will require further research. The BIM-model was enriched with information by using Inventors' drawing features. These were then presented in different views together with tables of information and dimensions after the company’s chosen information. The drawings, BIM-models and workflow were then evaluated with the Aknes Mekaniska company. In terms of its level of detail The BIM-model proved to be superfluous, for the company’s interests. The model took two weeks to produce, which was deemed too costly for the company in question. But the information attached to the model resulted in positive thoughts from the company regarding future BIM-integration, specifically in maintenance and supplementing documentation of older or modified machines. In summary, the results of the study points to the need of further research of digital integration in smaller manufacturing companies.
214

Automatiserad fotografering av verktygsförslitning med robot / Automated photography of tool wear using a robot

Mörk, Albin January 2023 (has links)
Vid skärande bearbetning av material för att framställa olika produkter med önskade egenskaper orsakas förslitningar av verktygen som är viktiga att fotografera och analysera för att uppskatta livslängden. Detta kräver erfaren personal med precision som är svår att upprepa där automation kan vara en lösning för att avlasta personal från ett monotont arbete.  Syftet med studien är att bidra med kunskap om hur man kan fotografera förslitningen av verktyg med hjälp av automation och ge förslag på en lösning. För att komma med ett lösningsförslag har en nulägesanalys genomförts med hjälp av observationer och intervjuerhos Sandvik Coromant, litteratursökning för att undersöka vad som gjorts inom området redan och simuleringar.  Resultatet blev ett konstruktionsförslag för en kamerafixtur och cykeltider för att fotografera samtliga förslitningsområden för de testade verktygen i ett simuleringsprogram. Om lösningsförslaget ska implementeras i verkligheten kommer den behöva testas för att med säkerhet kunna fotografera med tillräckligt bra fokus och ljussättning samt att kamerafixturen inte blir för skakig vid rörelse med roboten. / The use of cutting tools in cutting processing cause tool wear which need be analysed and photographed to predict tool life. To analyse the tool wear you need technicians with experience with precision that is hard to repeat in which automation could be a solution.  The purpose of this study is to contribute with knowledge on how you could photograph tool wear using automation and suggest a solution. This was done with a current situation analysis with the use of observation and interview of the technicians at Sandvik Coromant. A literature study was conducted to gather information about what has been done earlier in this field. Later a suggestion on the design of the camera fixture was made and simulated in a simulation program with the robotic cell to ensure it is possible to implement in real life.  The result from the study suggests that the camera fixture with the current robotic cell is capable of automatically photograph the tool wear of the tested tools. If the suggested camera fixture should be implemented in real life it needs to be tested with the camera to confirm it gets good enough focus and lightning inside the CNC-machine. It also needs to be tested so it does not wobble to much with the usage of the robot.
215

AUTOMATED INK : CNC Tattooing Robot

Thif, Yaman, Rendlert, Olle January 2020 (has links)
The art of tattooing has been around for centuries in human history and tattoos are still very popular in today’s society. Tattoos serve as a way to, for example, express people’s personalities, religious beliefs, or culture, and its growing popularity may lead to the need for more technological and automated alternatives. In this project, a computer numerical control plotter was built to investigate the possibilities of automation of tattooing, and the project focused on the possible limitations of performance and safety in an automated tattooing machine. The machine was built using two stepper motors connected with an H-Bot configuration that moved a gantry in the X and Y directions. A third stepper motor connected to a lead-screw was mounted on the gantry enabling movement in Z direction. Several tests were conducted in order to examine the performance of the machine. These tests were done using ink and whiteboard markers to draw different geometries on paper and the subject’s arm. The results showed limitations in the size of the tattoo as the machine could only draw on a flat surface and therefore had trouble adjusting to the uneven surface of an arm. The results also showed that the machine had some trouble drawing rounded geometries, such as circles, which meant that the circles, to a certain extent, got an elliptical appearance. It did however draw straight lines accurately. The main factors of this were believed to be a combination of sub-optimal assembly and the stepper motors being too weak to optimally operate with the H-Bot configuration. The safety risks were considered restricted when using a limit switch sensor and carefully calibrating the speed and movement in the Z-axis. / Tatueringskonsten har funnits i århundraden och tatueringar är fortfarande mycket populära i dagens samhälle. Tatueringar fungerar bland annat som ett sätt att uttrycka människors personligheter, religion eller kultur. Dess växande popularitet kan leda till ett behov av tekniska och automatiserade alternativ. I detta projekt byggdes en CNC-plotter för att undersöka möjligheterna till automatisering av tatueringar och projektet fokuserade på möjliga begränsningar av prestanda och säkerhet hos en automatiserad tatueringsmaskin. Maskinen byggdes med två stegmotorer anslutna med en H-Bot-konfiguration som flyttade en brygga i X- och Y-riktningarna. En tredje stegmotor ansluten till en ledskruv monterades på bryggan vilket möjliggjorde rörelse i Z-led. Flera tester genomfördes för att undersöka maskinens prestanda. Dessa tester gjordes med hjälp av bläck- och tuschpennor för att rita olika geometriska former på papper och testpersoners armar. Resultaten visade begränsningar i tatueringsstorleken eftersom maskinen bara kunde rita på en plan yta och därför hade problem med att anpassa sig till den ojämna ytan av en arm. Resultaten visade också att maskinen hade vissa problem med att rita runda geometrier, så som cirklar, vilket medförde att cirklarna, till en viss grad, fick ett elleptiskt utseende. Den ritade dock raka linjer med bra noggrannhet. De största anledningarna till detta tros vara en kombination av bristfällig montering och att stegmotorerna var för svaga för att optimalt kunna fungera med H-Bot-konfigurationen. Säkerhetsriskerna ansågs vara begränsade vid användning av en gränslägesgivare och noggrann kalibrering av hastigheten och rörelsen i Z-led.
216

Time and cost assessment of the manufacturing of tooling by metal casting in rapid prototyping sand moulds

Nyembwe, K., De Beer, D., Van der Walt, K., Bhero, S. January 2011 (has links)
Published Article / In this paper the time and cost parameters of tooling manufacturing by metal casting in rapid prototyping sand moulds are assessed and comparison is made with alternative tool making processes such as computer numerical control machining and investment casting (Paris Process). To that end two case studies obtained from local companies were carried out. The tool manufacturing was conducted according to a five steps process chain referred to as Rapid Casting for Tooling (RCT). These steps include CAD modelling, casting simulation, rapid prototyping, metal casting and finishing operations. In particular the Rapid Prototyping (RP) step for producing the sand moulds was achieved with the aid of an EOSINT S 550 Laser Sintering machine and a Spectrum 510 Three Dimensional Printer. The results indicate that RP is the rate determining step and cost driver of the proposed tooling manufacturing technique. In addition it was found that this tool making process is faster but more expensive than machining and investment casting.
217

ÖVERFRÄSEN : den bortglömda maskinen

Gustafsson, Adam January 2013 (has links)
Mitt examensarbete handlar om den utfasade snickerimaskinen överfräsen. Maskinen försvann från verkstäderna för mer än 30 år sedan och den erfarenhetsbaserad kunskapen om hur den användes finns hos före detta verkmästare och arbetare. Genom platsbesök och intervjuer på verkstäder och föreningar dokumenterar jag den immateriella kunskap som inte går att finna i litteraturen. Jag kommer sedan själv göra praktiska tester på maskinen för att verifiera den nyvunna kunskapen men också för att undersöka om maskinen har några användingsområden i det moderna snickeriet. / My thesis explores the overhead router, a formerly common but now rarely used and largely forgotten milling machine. My methods will be both practical and theoretical, and I will linger on three main questions; (1) How is the overhead router used? (2) Why did workers and foremen stop using the overhead router? And (3) what are the potential advantages of the overhead router? The theoretical side of my work will be based on interviews and field research from various workshops and woodwork organizations. The practical aspect of my thesis is an attempt to learn to use the overhead router personally, and in doing so, find out if the overhead router has a place in the contemporary woodworking shop.
218

Commande numérique ouverte : interpolation optimisée pour l'usinage 5 axes grande vitesse des surfaces complexes / Open CNC : optimized interpolation for 5-axis high speed machining of complex surfaces

Beudaert, Xavier 04 July 2013 (has links)
Le processus de fabrication des pièces usinées arrive à maturité concernant la fabrication assistée par ordinateur et la maîtrise du procédé d’usinage. Aujourd’hui, les perspectives d’améliorations importantes sont liées à l’optimisation de la commande numérique et de ses interactions avec le reste du processus de fabrication. L’objectif de cette thèse est donc de maîtriser les briques de base de la commande numérique pour optimiser le processus d’usinage 5 axes grande vitesse des surfaces complexes. La création d’une commande numérique ouverte nécessite le développement des algorithmes qui transforment le programme d’usinage en consignes échantillonnées pour les axes de la machine. La première partie des travaux consiste à rendre la géométrie suffisamment continue notamment pour les trajets interpolés linéairement en 5 axes qui présentent des discontinuités en tangence. Ensuite, l’interpolation temporelle du trajet crée la trajectoire d’usinage respectant les contraintes cinématiques et en particulier le jerk de chacun des 5 axes de la machine. L’implémentation matérielle de ces algorithmes permet de piloter une machine d’usinage grande vitesse 5 axes avec une commande numérique ouverte. Ainsi, les verrous technologiques associés aux commandes numériques industrielles sont levés et la chaîne numérique est entièrement contrôlée de la CFAO jusqu’au déplacement des axes. La maîtrise complète de la commande numérique offre la possibilité de définir exactement le trajet d’usinage à partir de la CAO sans introduire les écarts géométriques inhérents aux formats de description standards. L’interpolation de la trajectoire d’usinage directement sur la surface à usiner améliore de manière significative la qualité et la productivité de l’usinage des surfaces complexes. La commande numérique PREMIUM-OpenCNC permet la validation expérimentale de ces travaux et ouvre de nombreuses autres voies d’amélioration du processus de fabrication. / The manufacturing process reaches maturity concerning Computer Aided Manufacturing and cutting process performances. Nowadays, major improvements are linked to the optimization of the Computer Numerical Control and its interactions with the rest of the manufacturing process. The aim of this thesis is to control the basic components of a CNC in order to optimize the 5-axis high speed machining process of complex surfaces. The realization of an open CNC requires the development of algorithms which transform the machining program into command setpoints for the machine drives. The first part of this thesis allows to round the 5-axis discontinuities caused by the linear tool path interpolation commonly used. Then, a feedrate interpolation algorithm computes the trajectory while respecting the kinematical constraints of the machine and especially the jerk of each axis. The implementation of this work allows to control a 5-axis high speed machine with an open CNC. Hence, the technological barriers that prevent CNC optimizations are removed and the manufacturing process is under control from CAD/CAM to axis displacement. The complete control over the CNC offers the possibility to define the tool path exactly from Computer Aided Design entities without introducing any geometrical deviation generally induced by standard NC code. The direct interpolation of the trajectory on the machined surface significantly improves the quality and the productivity of complex surface machining. The PREMIUM-OpenCNC allows to prove experimentally the efficiency of this work and opens new ways for future manufacturing process improvements.
219

Tillämpning av modell för mätning av kvalitetsbristkostnader : Examensarbete om kvalitetsbristkostnader hos CNC Quality AB / Application of a model for measurement of costs of poor quality : A bachelor thesis about costs of poor quality at CNC Quality AB

Lundell Vakkuri, Samuel January 2019 (has links)
Begreppet kvalitetsbristkostnader handlar om att veta vad avsaknaden av kvalitet kostar en organisation samt dess effekter och orsakande faktorer. Att mäta kvalitetsbristkostnader gör det möjligt att identifiera förbättringsmöjligheter och i framtiden kunna mäta resultatet med kvalitetsarbetet. Denna rapport innefattar ett produktionstekniskt förbättringsprojekt genom analys av rutiner och arbetssätt vid mätning av kvalitetsbristkostnader hos CNC Quality Karlskoga AB. Syftet med arbetet är att bidra med rekommendationer för hur ett system för mätning av kvalitetsbristkostnader bör mätas i framtiden för att kontinuerligt kunna upprätta kvalitetsarbete för att maximera lönsamheten. Genom att kombinera information från tidigare kurser, intervjuer, litteraturstudie och induktiv benchmarkingstudie kunde kvalitetsbrister identifieras och sammanställas. Med hjälp av orsak-verkan-diagram och träddiagram kunde kostnadsdrivare pekas ut och orsakande parametrar tas fram. Många av kvalitetsbristkostnaderna är inte kvantifierbara och fick därför uppskattas i en schablonkostnad. Resultaten av rapporten är en lösning för att kunna mäta de mest lämpliga kvalitetsbristkostnaderna genom förändringar i rutinerna vid utökad kontroll samt vid justeringsarbeten. Två nya produktionsgrupper har tagits fram och implementerats i affärssystemet. Med denna modell är det möjligt att i framtiden kunna sköta ett kontinuerligt och väldisponerat kvalitetsarbete som resulterar i bättre lönsamhet. / The concept of costs of poor quality is about knowing what the lack of quality costs an organization, as well as its effects and causative factors. Measuring costs of poor quality makes it possible to identify improvement opportunities and in the future be able to measure the result with the quality work. This report includes a production technical improvement project by analyzing routines and working methods when measuring costs of poor quality at CNC Quality Karlskoga AB. The purpose of the work is to provide recommendations for how a system for measuring costs of poor quality should be measured in the future in order to continuously establish quality work to maximize profitability. By combining information from previous courses, interviews, literature study and inductive benchmarking study, quality defects could be identified and compiled. Using the cause-effect diagram and tree diagram, cost drivers could be pointed out and causative parameters developed. Many of the costs are not quantifiable and therefore had to be estimated at a standard cost. The results of the report are a solution for being able to measure the most appropriate costs through changes in the procedures for increased control and adjustment work. Two new production groups have been developed and implemented in the business system. With this model the user will in the future be able to handle a continuous and well-arranged quality work that results in better profitability.
220

Importância do binômio design e engenharia no beneficiamento de rejeito mineral de opala e ágata na produção de camafeus por usinagem CNC

Tessmann, Camila Sieburger January 2009 (has links)
No estado do Rio Grande do Sul, os garimpos de pedras preciosas estão distribuídos em duas regiões principais: no Distrito Mineiro de Ametista do Sul (maior produtor de ametista) e no Distrito Mineiro de Salto do Jacuí (maior produtor de ágata). Nestes dois distritos mineiros são explorados geodos, parcial ou totalmente preenchidos por camadas intercaladas de ágata, quartzo incolor, ametista, calcita e opala. O processo de extração desses geodos gera grande quantidade de rejeito, composto tanto pela rocha portadora do minério como também por minério de baixa qualidade. No município de Soledade se concentram as principais empresas de beneficiamento e também o comércio dos materiais gemológicos explorados no Rio Grande do Sul. No entanto, a maioria dos objetos produzidos que visam à exportação se repete nas diversas indústrias beneficiadoras sem diferencial aparente. A opala encontrada nos garimpos de Salto do Jacuí ocorre em muitas cores. A opala branca é a mais comum e não é valorizada, gerando, assim, significativa quantidade de rejeito. Através deste estudo, objetiva-se estabelecer uma metodologia de beneficiamento por usinagem CNC do rejeito de opala branca e ágata oriundo do Distrito Mineiro de Salto do Jacuí, que agregue valor pelo design e tecnologia. Considerando que os processos mais utilizados nas indústrias atualmente para a ágata, o tingimento e o corte em chapas, não se aplicam à opala, pode-se afirmar que a introdução da tecnologia de usinagem CNC neste setor pode auxiliar no aproveitamento desse material, ao modificá-los e valorizá-los como objetos de adorno sob a forma de camafeus. A metodologia empregada para a presente pesquisa consistiu de etapas de identificação dos locais de extração de ágata e de opala branca do Estado; avaliação dos procedimentos mais utilizados para beneficiamento destes materiais; estudo e análise do material por técnicas específicas; ensaios de usinagem CNC, análise das fresas utilizadas e dos materiais envolvidos após os processos de usinagem e desenvolvimento de produto. Foram realizados nove ensaios de usinagem e as análises posteriores, identificando nos resultados obtidos que, com as fresas adequadas destinadas ao desgaste (maior diâmetro) ou acabamento (menor diâmetro de ponta), quando utilizados em conjunto com parâmetros e estratégias de usinagem bem definidos, são suficientes para que se alcance o objetivo definido nesta pesquisa. / In the state of Rio Grande do Sul, the precious stones mines are distributed in two main regions: in the Mining District of South Amethyst (largest producer of amethyst) and the Mining District of the Salto Jacuí (largest producer of agate). In these two districts Geodis miners are exploited, partially or completely filled by intercalated layers of agate, clear quartz, amethyst, opal and calcite. The extraction process of Geodis generates large amounts of waste, comprising both the rock of the ore carrier as well as of low quality ore. In the municipality of Soledade focus the main company to benefit from trade and gemological materials used in Rio Grande do Sul. However, most of the objects produced aimed at the export is repeated in various industries benefit without apparent difference. The opal found in the mines of the Salto Jacuí appears in many colors. The white opal is the most common and is not valued, thus generating significant amount of waste. Through this study, that aims to establish a methodology for processing by the CNC machining waste of opal and white agate from the Mining District of the Salto Jacuí, a great value was added for design and technology. Whereas the most currently used in industries for agate, dyeing and cut into plates, are not applied to the opal, one can say that the introduction of CNC machining in this sector can assist in the exploitation of such material, to modify and value them as objects of adornment in the form of camafeus. The methodology used for this research consisted of steps of identifying locations for extraction of opal and white agate the state, evaluate the procedures used for further processing of these materials, study and analysis of the material by specific techniques, testing of CNC machining, analysis of cutters and materials used after the processes involved in machining and product development. Were conducted nine tests of machining and the subsequent analysis, identifying the results that, with the cutters suitable for the wear (larger diameter) or finishing (minor diameter of tip), when used together with parameters and machining strategies for well-defined, are sufficient to achieve the goal defined in this study.

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