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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.
1

Additive manufacturing of functional engineering components

Jones, Rhys Owen January 2013 (has links)
Additive Manufacturing (AM) is a class of echnologies whereby components are made in an additive, layer-by-layer fashion enabling production of complex parts in which complexity has little or no effect on cost. However typical components roduced using these techniques are basic structural items with no major strength requirement and low geometric tolerances made from a single material. his thesis develops a low-cost Fused Filament abrication (FFF) based AM technique to produce functional parts. This is achieved by through esearching and implementing new materials in ombination and using precise control of infill tool paths for existing materials. Robocasting has previously been shown to be extremely versatile, however is known to offer poorer build quality relative to its ess-versatile counterparts. Research was ndertaken to enable Robocasting to be combined with FFF to enable the print quality and practical benefits of FFF with the material flexibility of Robocasting. This resulted in the manufacture of several multiple-material omponents using the technique to demonstrate its potential. In order to minimise the number of materials required to obtain desired properties, the effect of process parameters such as layer height, infill angle, and infill porosity were investigated. In total over an order of agnitude variation in Young’s modulus and tensile strength were achieved, enabling these properties to be actively controlled within the manufactured components. Finally a novel non-eutectic low melting point alloy was developed to be compatible with the FFF process. Its greater viscosity compared to traditional eutectics resulted in improved print quality and the reliable deposition of electrically conductive track 0.57x0.25mm in cross-section. In addition the material is approximately three orders of magnitude more conductive that typical printable organic inks. A micro-controller was produced using the technique in conjunction with traditional electronics components. This represents the first time a functional electrical circuitry, with sufficient conductivity for the majority of applications and interfacing directly with standard electrical components, has been produced using a very low-cost AM technique such as FFF. The research undertaken builds components with substantially improved functionality relative to traditional AM products, enabling electromechanical components with varying mechanical and electrical properties. It is anticipated that this could substantially reduce the part-count for many engineering assemblies and open up Additive Manufacturing to many new applications.
2

Towards a self-manufacturing rapid prototyping machine

Sells, Edward A. January 2009 (has links)
Fused Filament Fabrication (FFF) is a layer manufacturing process which can manufacture highly complex components from CAD files using a polymer extruder. RepRap is an open-source project to produce a rapid prototyping machine which can manufacture its own parts using the FFF process. This thesis focuses on the mechanical design of the ‘RepRap printer’ and documents how it was conceived, developed, tested, and finally used to make a set of its own parts. Self-manufacture was demonstrated by assembling this set of parts into a working copy of the original machine. The child machine went on to demonstrate replication without degeneracy by successfully manufacturing one of its own parts. A part count analysis of the child machine, not including the fasteners it needed in its early development phase, identified a self-manufacturing ratio of 48%. This proportion is relatively low because the design adopts modularity and redundancy principles to encourage development. Should the machine’s design be adapted to fully demonstrate self-manufacture, this ratio could rise to 67% in the near future. To increase the ratio further, the machine needs three new tool heads to print resin, conductive alloy, and flexible polymer. These developments are achievable in the mid-future and could increase the self manufactured parts ratio to 94%. As this machine is the first version of the RepRap printer, these results are encouraging. Parts which the RepRap printer is unlikely to make until the far-future include some of the electronic components, motors, conductive cable, solenoids and a heating element. However, a 94% self-manufacturing ratio will qualify it as an assisted self-replicating machine. As with natural self-reproducing organisms, the printer will benefit from geometric growth and evolution. The author discusses how, by trading power, computing, feedstock and assembly for manufacturing capability with human beings, the RepRap printer may become a household item, offering a radical alternative to the way our society manufactures and consumes.
3

Stavba a aplikace 3D FDM tiskárny typu deltabot / Production and aplication of 3D FDM deltabot printer

Knapil, Josef January 2015 (has links)
The thesis describes design and aplication of 3D FDM printer type of delta. The first part describes methods of rapid prototyping. The second part describes 3D printers type of delta. The third part deals with construction and calibration of delta printer. In the fourth part are made suitable modifications to the design of the printer, to improve the quality of printing, which is then applied on a sample product. The final section is devoted to technical and economic evaluation.
4

Možnosti a omezení 3D RepRap tiskáren a jejich využití na trhu / Possibilities and limitations of RepRap 3D printers and their use in the market

Žižka, Ondřej January 2014 (has links)
Theoretical part of the thesis is devoted to the relationship of open source licensing to innovation, rapid prototyping and technologies used for 3D printing. There is also a comparison of selected RepRap printers. The main objective is to explore the possibilities and limitations of RepRap 3D printers while also analyzing their use in the Czech market. The aim of the application part is to test selected RepRap printer and explore the possibilities of 3D printing on these devices. In the last part of the thesis research has been conducted on the use of 3D printers. It's objective is to answer the main research question - who and for what purpose uses and aquires 3D printers
5

Vzdálená kontrola 3D tiskárny / Remote control of 3D printer

Kajzr, Miroslav January 2018 (has links)
The essence of this work is to summarize the knowledge about 3D printing, especially with FDM technologies. Create an overview of used FDM printing materials, identify their advantages and disadvantages, technical parameters and usability. Another purpose of the thesis is to examine the print quality and its problems and specify types of surface finishes for selected materials. The content also includes remote control and monitoring of the 3D print process using the Raspberry Pi microcomputer and the print server named Octoprint.
6

Povrchová úprava ABS součástí po 3D FDM tisku / Surface treatment of ABS parts after FDM 3D print

Světlík, David January 2015 (has links)
This master thesis deals with the surface treatment of parts made of plastic produced using FDM technology and design of technological device for surface treatment. The thesis describes FDM principles, according to performed experiments in a technological device there are suggested technological conditions for the surface treatment of parts made of ABS plastic. In the end of the thesis, there are calculated costs of the technological device and its operating costs, also mechanical properties, surface roughness and other specifications from before and after the treatment are compared.
7

3D FDM tiskárna reprap a parametry tisku / 3D FDM printer reprap and parameters of print

Kratochvíl, Tomáš January 2015 (has links)
This master thesis summarizes the current knowledge about non-commercial 3D printing FDM technology. The goal of this thesis is to demonstrate the gained knowledge by building a 3D printer which can partially replicate itself, and to evaluate its technological parameters. The experimental part of this work is focused on the impact of the changes in technological parameters of printing on mechanical properties of printed parts.
8

Methodological proposition to evaluate polymer recycling in open-source additive manufacturing contexts / Proposition d'une approche méthodologique permettant d'évaluer le recyclage des polymères dans un contexte de fabrication additive open-source

Cruz Sanchez, Fabio Alberto 09 December 2016 (has links)
En ce début de XXIème siècle, l’époque où seul la technique transformait la société toute entière est clairement révolue. Certes, les révolutions techniques sont là : interconnexion des personnes, explosion de l’internet, apparition de nouvelles formes d’énergies, de nouveaux procédés de production, de nouveaux matériaux etc... mais l’homme n'est plus un simple consommateur sensible au prix et aux incitations de l’état. Il souhaite être acteur et participer à l’utilisation des nouvelles technologies mais de manière raisonnée et en intégrant les grands enjeux sociétaux tels que le partage et la sauvegarde des ressources et matières premières. Cette thèse s’inscrit dans cette problématique globale: en effet tout au long du manuscrit nous réfléchissons à comment une révolution technique tel que la fabrication additive (FA) est prise en main par des citoyens dans des lieux de partage de la connaissance que sont les FabLabs, et plus précisément, s’il est possible et de quelle manière introduire de la durabilité dans le contexte open-source. Nous voyons dans un premier temps, comment la problématique sociétale forte du recyclage des matériaux se développe dans le contexte de la FA en générale et plus particulièrement nous proposons une revue bibliographique systématique sur le sujet. Dans un second temps nous recentrons notre recherche sur la FA dans le contexte open source et nous montrons que les machines dans ce contexte, bien qu’à des coûts très faibles par rapport aux machines professionnelles, ont cependant des niveaux de reproductibilités suffisant pour que l’on les utilise dans le cadre d’une recherche poussée. Dans le troisième chapitre nous proposons une méthodologie générale fixant l’étude du recyclage de polymères thermoplastiques dans le contexte open-source. Dans le quatrième chapitre nous utilisons la méthodologie vu précédemment pour le recyclage de l’acide polylactique (PLA). Nous montrons le niveau de dégradation de la matière à travers l’ensemble du procédé et concluons qu’il est possible de recycler le PLA pour l’impression 3D mais dans une moindre mesure que pour les procédés d’injection. Enfin nous concluons et proposons en perspective d’étudier le recyclage en circuit court d’autres polymères thermoplastique / Since the beginning of the XXI century, we can recognize that several technical (r)evolutions have changed the way we conceived our world. New realities have appeared thanks to the information and communication technologies (e.g. Internet), peer-to-peer dynamics (e.g. open software/hardware, collaborative economy), new means of production (fablabs, hackerspaces), among others. One of the impacts of this technical ecosystem is the individual's empowerment that changes the relationship between consumer and producer. For instance, we observe an evolution of role passing from a passive consumer towards an active prosumer, where this latter considers not only economic aspects, but also social and environmental issues.This thesis is integrated in this global issue; indeed, throughout the manuscript we analyze about the impact of open-source (OS) Additive Manufacturing (AM) (also as known as open-source 3D printing or just 3D printing) in the light of the sustainability issues. The democratization of OS AM and the creation of spaces for co-creation (e.g. FabLabs) proved the interest for changes in the established roles. Therefore, we are interested in how this OS technology could develop sustainable waste management options through a polymer recycling process. In a first phase, we present the concept of additive manufacturing (AM) and its importance on sustainability issues. A systematic literature review related to the material recycling advances in the commercial and open-source (OS) AM is developed with a focus on thermoplastic polymer recycling.In a second phase, our aim is to validate open-source AM systems as a reliable manufacturing tool. We develop and test an experimental protocol in order to evaluate the dimensional performance using as case study a representative OS 3D printer: called FoldaRap. It was found that the International Standard Tolerance Grade of this machine is situated between IT14 and IT16. We conclude that the dimensional performance of this case study is comparable to the commercial AM systems, taking into account the important different in terms of machine cost. In a third phase, we center our attention on the recycling process and we propose a systematic methodology to evaluate the feasibility of the use of recycled thermoplastic polymer in OS 3D printers. A case study is developed with the evaluation of the recycling process using polylactid acid (PLA). The results allow us to conclude that the use of recycled PLA is technically feasible. Nevertheless, the degradation of the material is more important than in other traditional manufacturing systems (e.g. injection). Finally, we concludes and propose as perspectives, the study of a distributed recycling process for other type of polymers
9

Modifikation av Slicer till 3D-skrivare med Flerfärgsfunktion / Modification in Slicer for 3D-Printer with Multi-material function

Hirasawa, Lucas January 2024 (has links)
Denna rapport detaljerar ett examensarbete där användbarheten på en lokalt skapad 3D-skrivare förbättrats i syfte av att tillåta skrivarens användning av studenter på KTH Södertälje. Skrivarens har ursprungligen byggts för att agera som ett pågående projekt som kan återupptas som examensarbete, varav detta är det tredje. Skrivaren i fråga är en FFF-skrivare i ”box” stil med utskriftsvolymen 400 x 400 x 375 mm. Vid projektstart är skrivaren i nominellt användbart skick men saknar dokumentation, processrutiner och användbara slicerprofiler. Skrivaren besitter även hårdvaran för att tillåta utskrifter med två material men denna funktion har aldrig implementerats. Framtagningen av slicerprofiler har tagit upp majoriteten av arbetet och har utförts genom iterativ testning där inställningar modifieras och testas, vartefter positiva ändringar implementeras för att gradvis eliminera defekter och minska haveririsk. Projektet har levererat en full slicerprofil som tillåter pålitliga utskrifter med två olika PLA-filament samt en användarmanual till skrivaren. Utöver användarverktygen så detaljeras även de reparationsarbeten och hårdvaruändringar som gjorts. Profil, manual, rådata och filer för utskrivna komponenter är tillgängliga i en projektmapp som kan hittas från en länk i början av kapitel 4. / This report details a thesis project for getting a 3D-printer internally built at KTH Södertälje into a state where it can be used by other students for unrelated projects. The printer acts as an ongoing project that can be used for thesis work, with this project in particular being the third in line. The printer in question is an FFF-printer with the ”box” configuration and a print volume of 400 x 400 x 375 mm. At project start, the printer is nominally in working condition but lacks any documentation for proper handling and slicer settings. Additionally, its multi-material function has never been successfully implemented. Adjustment of slicer settings is done using iterative testing, wherein settings are modified and tested, with positive changes being integrated and negative changes discarded with the intent of removing defects and minimizing risk of print failure. The project has delivered a slicer profile for Cura capable of reliably printing with two different PLA filaments as well as a user manual. Hardware upgrades and repair work has also been detailed. The profile, user manual, raw data and object files for upgrades and spares can be found through a link in the beginning of chapter 4.
10

Live Software for RepRap Assembly Workshops / Live programvara för RepRap monteringskurser

Ludvigsen, Torbjørn January 2016 (has links)
A key step when initiating robot powered production is setting up the control software.This can be a threshold for operators, especially if the software is fragmented and system requirements are extensive.One way to address this is to pre-configure all the control programs and bundle them with a system that fulfills all the requirements. In this work a live operating system (OS) is loaded with control software and configured to  meet the needs of those who have just assembled their first 3D printer.The problem of downloading, configuring and installing various 3D printer controlling programs  is reduced to the problem of distributing and booting the live OS. The solution of loading it onto bootable USB drives is tested and evaluated in the context of a commercial RepRap Assembly Workshop (RAW),  an event where people pay for RepRap 3D printer parts as well as assembly and usage supervision.The RAW is unusually short, so the bootable USB drives' potential to help  RAW hosts with particularly tight time schemes is tested. The results show a limited success.The USB drive is documented not to work for 3 participant groups out of a total of 11 groups.As a solution to fragmented software and diverse system requirements, the live OS is found to work well once booted.Several routes to make the live OS more easily bootable are discussed. Usage examples beyond drop-in replacing existing RAW software setup procedures are discussed. / Alla som startar upp robotiserad produktion måste få igång och börja använda styrprogramvaran.Detta kan inebära en hög tröskel för operatörer, specielt om programen är många och har olika gränssnitt och systemkrav.Ett sätt att hjälpa operatörerna komma igång är att konfigurera alla styrprogram på förhand  och bunta ihop dem med ett system som uppfyller alla krav. I detta arbetet laddas ett live operativsystem med styrprogramvara och konfigureras för att lätt kunna  användas av någon som precis har satt ihop sin första 3D-skrivare.Problemen med hemladdning, konfigurering och installation av en rad olika styrprogram  reduceras till problemet att distribuera och boota live operativsystemet. Lösningen att lasta live-systemet på startbara (eng. bootable) USB-minnen testas och utvärderas  som en del av en kommersiell RepRap monteringskurs (eng. RepRap Assembly Workshop),  ett event där deltagare betalar för RepRap 3D-skrivardelar,  hjälp med att montera ihop dem och med att använda de färdiga 3D-skrivarna.Den undersökta monteringskursen är ovanligt kort, så startbara USB-minnens potential att  underlätta för tidsprässade kursvärdar testas. Resultaten visar en begränsad framgång.Vi visar hur 3 av 11 deltagargrupper inte lyckas använda de startbara USB-minnena.Som en lösning på fragmenterad mjukvara med stora systemkrav fungerar live operativsystemet bra när det väl har startats.Olika sätt att göra live-systemet lättare att starta diskuteras. Tillämpningsområden utöver att ersätta existerande programuppsättslösningar för RepRap monteringskurser diskuteras.

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