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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.
21

Life Cycle Assessment of a 3D printer : A comparative and attributional life cycle assessment of 3D printer / Livscykelbedömning av 3D-skrivare

Senthil, Rishi Akash Chinnakonda January 2022 (has links)
Three-dimensional (3D) bio printing offers a wide range of applications, including the placement, design, and patterning of biological components such as living cells, nucleic acids, tissues, and many more. Bioprinting has seen great growth and breakthroughs in recent years, particularly in 3D printing. The company (which do not want to be named) produce a user- friendly and adaptable bioprinter that provides the best bioprinting experience.  This thesis examines the environmental consequences of a 3D printer, through Life Cycle Assessment (LCA) over its lifetime which is anticipated to be 1 year for the study. To examine the impacts of the 3D printer over its lifetime, a comparative life cycle assessment (Comparative LCA) and attributional life cycle assessment (ALCA) was undertaken between the supply chains known as linear supply chain (LSC) and circular supply chain (CSC). Global warming (GW), terrestrial acidification (TA), freshwater eutrophication (FET), terrestrial ecotoxicity (TEC), freshwater ecotoxicity (FEC), marine ecotoxicity (MEC), land use (LU), and water consumption (WC) are the impact categories chosen for the study from ReCiPe 2016 (H) Midpoint.  According to the LCA results, the impacts generated by CSC are smaller than those contributed by LSC, and the impact categories that are most and least affected are recognized. Furthermore, from the 3D printer, potential hotspots with higher contributions were discovered. Airway transfer of 3D printer’s components from their manufacturing site to the company had a significant impact on the impact categories chosen. Printed Circuit Boards (PCB) used in 3D printers are another influential component that has a significant impact on the impact categories. When specifically looking, the manufacture of Integrated Circuits (IC) has a greater impact, which reflects on PCB production.  To identify the opportunities and improve 3D printer’s environmental performance, a sensitivity analysis is carried out, which yields results on how to improve its environmental performance. As a result, it is suggested that airway transportation be modified with seaway transportation, that virgin aluminium and copper materials be replaced with its scrap material / Tredimensionell (3D) bioprinting erbjuder en mängd olika applikationer, inklusive placering, design och mönster av biologiska komponenter, såsom levande celler, nukleinsyror, vävnader och mer. De senaste åren har bioprinting fått många genombrott och vuxit mycket, framför allt inom 3D-printing. Företaget (som inte vill bli namngivet) producerar en användarvänlig och anpassningsbar bioprinter som ger den bästa bioprinterupplevelsen.  Detta examensarbete undersöker den miljöpåverkan som en 3D-skrivare har, genom livscykelanalys (LCA) under sin livslängd, som beräknas vara 1 år för denna studie. För att undersöka 3D-skrivarens påverkan under dess livstid har en jämförande livscykelanalys (Comparative LCA) och attributionell livscykelanalys genomförts mellan försörjningskedjorna, som kallas linjär försörjningskedja (LSC) och cirkulär försörjningskedja (CSC). Global uppvärmning (GW), terrestrisk försurning (TA), sötvattenseutrofiering (FET), terrestrisk ekotoxicitet (TEC), sötvattenekotoxicitet (FEC), marin ekotoxicitet (MEC), markanvändning (LU) och vattenförbrukning (WC) är kategorier valda för studier från ReCiPe 2016 (H) Mid Point. Enligt LCA-resultat är miljöpåverkan från CSC mindre än den som LSC bidrar med. Dessutom, med 3D-skrivare, har potentiella hotspots med högre bidrag upptäckts.  . Luftburen överföring av 3D-skrivarkomponenter från deras tillverkningsplats till företaget hade en inverkan på de berörda kategorierna. Printed Circuit Boards (PCB) som används i 3D-skrivare är en annan påverkande komponent. Mer specifikt har tillverkning av integrerade kretsar (IC) en stor inverkan.  För att, identifiera utsläpp och möjligheter och förbättra 3D-skrivarens miljöprestanda, genomförs en känslighetsanalys som ger resultat om hur man kan förbättra dess miljöprestanda. Som ett resultat föreslås att flygtransporter ersätts med sjötransporter, att jungfruligt aluminium och kopparmaterial ersätts med dess ersätts material.
22

Korekce barev 3D scanneru a 3D tiskárny / Color Correction for 3D scanner and 3D printer

Kratochvíla, Michael January 2019 (has links)
This thesis deals with color correction of a chain that starts with the 3D Artec MHT scanner, and ends with the 3D printers (CJP – Color Jet Printing technology). In principle, it is necessary to control the color interpretation of the entire chain from the scanning of real models to the 3D print model. With color properties and their color shade, including color textures. The principle of model surface scanning using a 3D scanner is in the same principle as photo camera which scans using a conventional CMOS chip. For this reason, color palettes were scanned using the photo camera and the resulting digital data were analyzed by the Darktable software. This analysis consisted of comparing the scanned color shades of the surface with the spectrofotometer measured data. The main goal of this method was to achieve color precision in the digital data during their acquirement, adjustment and interpretation. Then the same principle was applied to the data acquired by the 3D scanner to create an ICC profile of the 3D scanner. Because the 3D printer (CJP – Color Jet Printing) uses the same principle as the 2D printer, the 2D printing device calibration principle was used again to calibrate it. There have been defined procedures that adjust the color shade to the spectrophotometrically correct shades of the resulting print on a 3D printer. Color swatches were also printed for print quality verification. It has been found that with photo camera, which was used for objective measurement in the L*a*b* coordinates of independent space, any color setting and their adjustment is very sensitive to even small imprecisions. It has been found that it is not easy to obtain accurate colors within the Detla E
23

Design of a filament fuser : Reducing 3D-printer filament waste / Design av en filamentsvetsare : Reducera materialsvinn av 3D-skrivare

Kanbour, Omar January 2022 (has links)
There has been a significant rise of users in the 3D-printer community. A common dilemma amongst users is how to handle spools of plastic filament that does not contain enough filament for an arbitrary print. This report explores the possibility of fusing strands of filament together from two different spools into one spool by the method of fusion bonding. This concept of plastic bonding generally consists of the following three steps. Preparing the surface area, heating the polymer and physically pushing the filament strands on to each other. Fusion bonding proved to be successful for temperatures between 150-190 ◦C without reducing required tensile strength for printing. There was a clear deterioration in the ability to follow tight curves for the fused filament. This showed in the result where many of the welded strands snapped when conducting the bending test. The welded filament had an average diameter of 1.992 mm. It appears that the filament bond formed based on the geometry of the PTFE tube that acted like a mold. It was concluded that the welded filament bond could improve if the used PTFE-tube had a diameter closer to 1.75 mm. Possible improvements were discussed where an example of using PTFE coating could improve the quality of the fuse in terms of strand diameter. / Användningen av 3D-skrivare har ökat markant bland konsumenter. En vanlig situation som uppstår är att kvarvarande filamentrulle inte har tillräckligt med material över för en godtycklig utskrift. Den här rapporten avser att behandla möjligheten att svetsa ihop två olika plasttrådar av filament till en enda tråd och därefter rulla ihop den sammansvetsade plasten till en filamantrulle. Metoden som användes för att utföra svetsningen kallas för fusion bonding. Det finns flera olika varianter av denna metod. För att utföra sammansvetsning med fusion bonding krävs följande tre steg, förberedelse av ytan på den tilltänkta svetsen, upphettning av polymererna och därefter fysiskt röra de upphettade polymererna mot varandra tills kontakt uppstår. Fusion bonding visade sig vara en fungerande metod att sammansvetsa filament med för temperaturer mellan 150-190◦C utan att påverka den nödvändiga styrkan för att klara av en utskrift. Böjtestet påvisade en kraftig försämring av det sammansvetsade materialets förmåga att böja sig. Det visade sig även att medeldiametern vid sammansvetsningen var 1.992 mm. Slutsatsen som drogs av resultatet var att sammansvetsningen formade sig efter PTFE-tuben som agerade som en form åt polymererna. En möjlig förbättring som diskuterades var att använda PTFE-beläggningpå aluminiumblocket för att minska skillnaden i diametern mellan sammansvetsningen och originaldiametern.
24

Multicolor 3D printing : An analysis of the characteristics of multicolor 3Dprinting

Patkhullaev, Davron, Melake, Yonas January 2021 (has links)
3D printing has risen in popularity due to its capabilities which enable rapid prototyping and printing structures that were impossible to produce before and partially because of technological development in recent years. Most low-cost printers, based on the fused filament fabrication process, are capable of printing a single filament at a time that limits and complicates multicolor and multi-material 3D printing. Therefore, investigating and building a multicolor 3D printer have been chosen as a degree project in order to provide an understanding for multicolor 3D printing. The project was started with an investigation of different possibilities and potential solutions. After that, a visual CAD model was created in Solid Edge, and a virtual model was constructed by using Acumen. Lastly, accumulated ideas were implemented into creating a prototype. Construction of the prototype was accomplished successfully, and several experiments were executed to determine its capabilities and limitations. The results showed that the printer has high precision in XY-plane and is less precise in Z-axis. The printer was able to print 45 different colored objects, of which only 24 were chosen as distinct colors that the human eye could distinguish. One of the main challenges with a single nozzle multicolor 3D printing compared to a single-color printing is constant heatsink clogging. Another challenge is to create a well-integrated system where hardware and software comply perfectly in a manner that desired prints are obtained. / Se dokumentfil
25

Práce s tiskárnami v Linuxu / Working with printers in Linux

KOUBA, Stanislav January 2010 (has links)
This thesis is dedicated to explain how to work with printers in Linux. It is devided into six chapters. First one shortly describes what types of printers are commonly available. The communication languages for printers is recorded in chapter two. In third chapter We have describe how connect the printers to the computer. How to work with printers in Linux can see in chapter four. In chapter five we describes the printers drivers. Last chapter I try to write my own printer driver.
26

3D tiskárna typu Delta / Delta type of 3D printer

Němec, Radek January 2019 (has links)
This master thesis is about design and construction of FDM delta 3D printer which consists of 32-bit electronics, magnetics printer head and other necessary peripheries. Opening chapters of this thesis are about theory of 3D printing and its methods with description of FDM 3D printers and summarization of FDM plastic materials used for 3D printing. The next part is about used electronics and problematic of heat transfer. The main part of this thesis describes design and construction of 3D printer and its necessary peripheries, which includes creation of its 3D model and application for 32bit controller. 3D model of delta 3D printer and its heating components was created in CAD software SolidWorks. The last part includes description of commissioning and calibration of delta 3D printer with summarization of economic aspects of its creation.
27

Social media's significance on the need recognition and information search, in B2B investment decisions of 3D printers.

Boström, Gustav January 2015 (has links)
This study examines what significance social media (Facebook, LinkedIn, Twitter and Instagram) may have in regard to clients need recognition and information search, in B2B investment decision making of desktop 3D printers. The study was made on 121 respondents from the 3D printer reseller company 3DVerkstan’s customer base. Need recognition and information search are the two first steps of five, in the consumer behavioral Engel Blackwell Miniard (EBM) model of decision making. To get a better perspective of what role social media have in B2B marketing, a broad investigation of the 3D print owners need recognition and information search has been conducted through a survey built from the EBM-model, and the clients media consumption. A wide range of communication channels has been examined in order to draw conclusions from what role social media play as whole. As social media is an unexplored field for B2B marketing, an interview with the CMO of Telia Sonera Sweden, Magnus Andersson was held to get insights of how they currently use social media in B2B as a best-in-class case. This study aims to give foundational directives for social media’s significance for B2B companies in the technology. The findings in this study indicates that social media has a great potential exposure to influence and inspire need recognition. Especially for Facebook, decent potential exposure for LinkedIn and Instagram. Not very good for Twitter. Although, almost none were first exposed to 3D printing on social media. Social media was not searched for information, and the few that did searched for reviews. The respondents primarily searched on online sources only. Most respondents conducted one search step where they focused on finding a source with compiled information to conveniently grasp the 3D printer market. Either on Youtube to look for unbiased 3D print reviews. Or through a convenient recommendation from friends and resellers of the most suitable 3D printer in relation to their objective. Technical specification, price, customer reviews, service & support and user case quality caught their attention after finding their preferred source of information retrieval. Convenient personalized packaging in review form with the above stated attributes could be used to inspire customers on social media. Directed towards the use motives; prototyping, hobby/home use or custom production.
28

Parameter Tuning in a Jet Printing Machine usingReinforcement Learning / Parameterjustering i en jet printermaskin med enFörstärkande inlärningsalgoritm

MURTAZA, ALEXANDER January 2021 (has links)
Surface mount technology is a common way to assembly electrical components onto PrintedCircuit Boards (PCB). To assemble the components, solder paste is used. One way to apply solderpaste onto PCB is jet printing.The quality of the solder paste deposits on the PCB depends on the properties of the solder pasteand the ejection parameters settings of the jet printer. Every solder paste is unique with its owncharacteristics. Solder paste dots are of good quality if the positioning of the dot is good, the dotis circular, and the number of satellites is at a minimum. A satellite is a droplet that has fallenoutside the main droplet. The parameters that have the most effect on the solder paste are thewaveform parameters Rise time and Voltage level.This master thesis examined the possibility to design and implement a feedback-based machinelearning algorithm that can find the most suitable value for the Rise time and Voltage level, thatgives good quality of the solder paste deposits. The algorithm that was used was a ReinforcementLearning algorithm. Reinforcement Learning is a reward-based learning algorithm where an agentlearns to interact with an environment by using trial and error. The specific algorithm that wasused was a Deep-Q-Learning algorithm. In this master thesis, it was also examined how the cameraresolution affects the decision of the algorithm. To see the implication of the camera resolution,two machines were used, an older and a newer machine were used where one of the biggestdifferences is that the camera resolution.It was concluded that a Deep-Q-Learning algorithm can be used to find the most suitable value forthe waveform parameters Rise time and Voltage level, which results in specified quality of thesolder paste deposits. It was also concluded that the algorithm converges faster for a lower cameraresolution, but the results obtained are more optional with the higher camera resolution. / Ytmontering är en metod som används för att montera elektriska komponenter på kretskort. Föratt kunna montera komponenterna används lödpasta. En teknik för att applicera lödpasta påkretskort är jet printing.Kvaliteten på lödpastavolymen på ett kretskort beror dels på egenskaperna hos lödpastan, dels påutskjutningssparametrarna hos jetprintern. Varje lödpasta är unik med hänsyn till flödesegenskaper. En lödpastadeposition har god kvalitet om depositionen har en bra position, omdepositionen är cirkulär och om mängden satelliter är minimal. En satellit är en droppe lödpastasom fallit utanför huvuddepositionen. Parametrarna som har störst effekt på lödpasta ärvågformsparameterna stigtid och spänningsnivå.Detta examensarbete undersökte möjligheten att hitta en feedbackbaserad maskininlärningsalgoritm som kan hitta de mest lämpliga värdena för stigtiden och spänningsnivå som ger godkvalitet på lödpastadepositionen. Algoritmen som användes var en Förstärkande inlärningsalgoritm.Förstärkande inlärning är en belöningsbaserad inlärningsalgoritm där en agent lär sig attinteragera med en miljö genom att använda trial and error. Den specifika algoritmen som användesvar en Deep-Q-Learning-algoritm. I examensarbetet undersöktes även hur kameraupplösningenspåverkar algoritmen och dess beslut. För att undersöka detta användes två maskiner, en nyare ochäldre version där att kameraupplösningen är lägre.Slutsatsen som drogs var att en Deep-Q-Learning-algoritm kan användas för att hitta det mestlämpliga värdena för vågformsparametrarna stigtid och spänningsnivå. En annan slutsats somdrogs var att algoritmen konvergerade snabbare när kameraupplösningen är lägre. Parapeternasom är optimala för den kameran med lägre upplösning är inte optimala för den kameran medhögre upplösning.
29

Digitalisering av byggsektorn / Digitalization of the constructional section

Al Sadi, Sarmad, Hododi, Dylan January 2018 (has links)
Syfte: Den digitala utvecklingen inom byggproduktionssektorn ligger efter jämfört med många andra branscher och har fått ryktet om att vara rent av konservativ. Att säga att utvecklingen står stilla stämmer inte då majoriteten av företagen arbetar aktivt för en mer digitaliserad sektor. Trots detta domineras produktionsplatserna av pappersdokument, icke autonoma system och själva arbetet utförs mer eller mindre på samma sätt som det gjort i flera decennier. Trots att flertalet digitala verktyg och implementeringsmodeller finns tillgängliga möter dem inom byggproduktionssektorn en hel del motstånd. Denna rapport granskar de digitala innovationer som är på uppgång och som kan göra betydande nytta inom byggproduktion. Metod: Via sökmotorer på högskolans databas, samt internet gjordes insamling av rådata som sedan skulle analyseras och ligga till grund för kvalitativ insamlingsmetod. Litteraturstudien var grundpelaren som betingade de semistrukturerade intervjuerna, som i sin tur möjliggjorde en jämförelse mellan det teoretiska ramverket och intervjuresultat. Resultat: En klar majoriteten av de intervjuade aktörerna ansåg att 3D-skrivaren någon gång i framtiden kommer att inta byggsektorn. En implementering av 3D-skrivaren skulle medföra kortare produktionstider, reducerade produktionskostnader, eliminering av spill och mindre arbetskostnader. Autonoma systems inträde i byggproduktionssektorn kommer förmodligen inte ske inom en snar framtid då olika byggprojekt skiljer sig åt väldigt mycket. Hade byggandet blivit mer monotont skulle det underlätta väldigt mycket, men i dagsläget är sällan ett projekt det andra likt. Big data är en innovation som skulle kunna revolutionera byggbranschen på flera håll. Respondenterna förstod dock inte begreppets innebörd vilket tyder på att det inte satsas någonting på Big data inom produktionssektorn. Möjligheterna för Big data är många och det kan bland annat användas för effektivare kommunikation, effektivisering av produktionsplatsen, mer detaljerad koll på olika maskiner och mer kontrollerade material leveranser. Konsekvenser: För en allmänt lyckad implementering av 3D-skrivaren krävs det att även de mindre företagen kan införskaffa apparaten. De större företagen riskerar annars att konkurrera ut de mindre företagen. Då betong i allmänhet är ett material med förhållandevis hög miljöpåverkan medför detta konsekvenser för miljön som redan befinner sig i en utsatt position. Då det arbetas väldigt aktivt med att förbättra omvärldens miljöpåverkan är det därför viktigt att lägga fokus på att försöka producera mer miljövänlig betong. Begränsningar: Studien begränsades till ett fåtal svenska byggföretag i göteborgsregionen. I rapporten tas därför endast de fåtal respondenters åsikter med. / Purpose: The digital progress is slow within the constructional sector in comparison to other type of businesses and it has the reputation of being relatively conservative. To say that the progress is standing still would be mistake since the majority of constructional companies are working actively for a more digital construction site. Even though these companies are working hard towards a more digital sector the construction site is dominated by paper documents, non-autonomic systems and the labor is done the same way as it has been done for decades. Even though multiple digital tools and implementation models are available the construction sector is facing a lot of resistance. This report examines those digital innovations that are on the rampaging and can do a significant good within the construction sector. Method: Through search engines at the university's database, as well as the internet, collection of raw data was collected, which would then be analyzed and underlie for qualitative collection methods. The literature study was the foundation of the semistructured interviews, which in turn enabled a comparison between the theoretical framework and interview results. Findings: A vast majority of the interviewed participants believe that the 3D-printer sometime in the future may be used within the construction sector. An implementation of the 3D-printer would induce shorter production times, reduced production costs, elimination of waste and reduced costs for labor. Autonomic systems will probably not be implemented on construction sites within a short future since different construction projects are to diverse. If the construction would become more monotonic it would ease considerably, but today one project is rarely analogous to the other. Big data is an innovation that could revolutionize the construction sector in a lot of different ways. The respondents did not understand the meaning of the term, which interpret that it is not an innovation in focus for the time being. The possibilities of Big data are substantial and it could be used for more effective communication, more efficiency within the construction site, more detailed checkups of machinery and more controlled building material checkups. Implications: For a generally successful implementation of 3D-printers they need to be affordable for the smaller companies. Otherwise the larger firms risk to put the smaller firms out of business. Since concrete is a material with a relatively large impact on the environment this may cause consequences for the environment in the future since its already in an exposed situation. Since it´s globally working actively with improving the environment the focus should be in producing more environmentally acceptable concrete for the 31d-printers. Limitations: The study was limited to a handful of Swedish constructional companies within the Gothenburg region. In the report, only the opinions of a few respondent are taken to consideration.
30

Novas metodologias para a fabricação de piezoeletretos termo-formados / New technologies for the manufacture of piezoelectrets thermo-formed

Assagra, Yuri Andrey Olivato 28 August 2015 (has links)
Há vários métodos descritos na literatura sobre a forma como os piezoeletretos ou ferroeletretos podem ser fabricados, sendo que cada uma dessas técnicas apresenta suas vantagens e desvantagens. Por exemplo, espumas de polipropileno (PP) são fáceis de serem processadas em grande escala aliada a um baixo custo de produção, entretanto, seu efeito piezoelétrico é dependente da temperatura, assim como não há um controle dos vazios internos durante sua fabricação, ocasionando uma heterogeneidade da geometria desses vazios. Por outro lado, em outros métodos as dimensões das cavidades podem ser controlada e polímeros termicamente mais estáveis podem ser utilizados, no entanto, a um maior custo de produção. Em relação aos métodos que visam a produção dos piezoeletretos, neste trabalho é apresentada uma nova técnica baseada em termo selagem e template de água para criar piezoeletretos com canais tubulares abertos. Este tipo de estrutura vazada foi inicialmente produzida pela laminação de filmes de etileno propileno fluorado (FEP) com o template de politetrafluoretileno (PTFE) entre eles, sendo o template descartado após a laminação, gerando resíduos. Com a substituição do template de PTFE pela água na etapa de produção dos novos piezoeletretos, foi possível eliminar o descarte de resíduos sólidos ao mesmo tempo em que um tratamento químico foi efetuado na superfície do filme. Pelo método desenvolvido, a estabilidade térmica do piezoeletreto foi melhorada sem a necessidade de um tratamento prévio ou posterior dos filmes, diminuindo assim o custo de produção. Outro método inovador para produção dos piezoeletretos também foi exposto neste trabalho. Essa inovação consiste na fabricação de piezoeletretos com cavidades controladas por meio da impressão de filmes de ABS. Para a impressão dos filmes uma impressora 3D de baixo custo foi utilizada. / There are several methods described in the literature on how piezoelectrets or ferroelectrets can be manufactured, each of these techniques present their advantages and disadvantages. For example, foamed polypropylene (PP) are easy to be processed on a large scale combined with a low cost of production, however, its piezoelectric effect is temperature dependent, and there is no control of internal voids during its manufacture, causing a heterogeneity of the geometry of these empty. Furthermore, in other methods the cavities dimensions can be controlled and more thermally stable polymers can be used, however, with a higher production cost. Regarding the methods for producing piezoelectrets, in this work we present a new technique based on hot sealing and water template for creating multi-layered piezoelectrets with open-tubular channels. This type of voided structure have been initially produced by laminating fluoroethylene-propylene (FEP) films with a polytetrafluorethylene (PTFE) template in between although the template was discarded after lamination, creating residual waste. With the replacement of the PTFE template by water in the production step of the new piezoelectrets, it was possible to eliminate the disposal of solid waste at the same time a chemical treatment was performed on the film surface. By the developed method, the piezoelectrets thermal stability was improved without the need for a prior or subsequent treatment of the films, reducing the production cost. Another innovative method for production of piezoelectrets was also exposed in this work. This innovation consists in manufacturing piezoelectrets with cavities controlled by printing ABS films. In order to print the films, a 3D printer was used.

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