Dissertations / Theses: '3D printing technologies'

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Blakeway, Adam M. "Experiments with 3D printing technologies in masonry construction." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/103493.

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Thesis: S.B., Massachusetts Institute of Technology, Department of Architecture, February 2016.
Cataloged from PDF version of thesis. "June 2014."
Includes bibliographical references (page 34).
Modern masonry construction finds itself in a cyclical pattern of "more of the same," insisting on standardized, basic designs consisting of little more than uniform stones laid in regular courses, which do little to add to the variability of the modem world. While these forms attain a surety in structural stability, they offer little in the form of variable aesthetics. 3D-printing, consistently hailed as one of the most promising developments of the 21 " century, allowing individuals from every walk of life to create and produce in real time, has, contrarily, failed to grasp our greater aspirations in the field of Architecture. Most attempts at the incorporation of 3D-printing technology in Architecture have simply been to scale the technologies to print larger and larger objects, eventually working up to entire buildings. While these efforts are beneficial in some ways, they consist of numerous drawbacks which make these types of strategies ultimately implausible, at least for the moment. Modern construction, once thought to be secure in its standards of structure and implementation, is now being challenged to develop designs far more elaborate than their "glass tower" counterparts by pushing the boundaries of what architectural moves are possible. The long held beliefs that stone must be orthogonal and uniform to be utilized in large-scale construction projects are being revamped in the wake of the 3D printing boom. This thesis seeks to find a synthesis between these two methods of modern construction, unifying the versatility and variability of 3D-printing and the stability and natural aesthetic of masonry, to create viable and aesthetically appealing architectural forms for the 2 1st century.
by Adam M. Blakeway.
S.B.

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Zítka, Lukáš. "Inovace 3D tiskárny typu Rep Rap." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-319860.

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The present Master thesis is focused on innovation and verification of the functionality of a 3D RepRap. The theoretical part of the thesis characterizes individual additive technologies. The practical part is focused on the design of the technical modifications of the printer in order to achieve the quality of the printing, while the current 3D printer design is compared with the innovative solution. The practical part tests the setting of print parameters, various materials for 3D printing and necessary finishing operations. The thesis is completed

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Ovchar, Mark. "Modern technologies in building." Thesis, Дніпропетровський національний університет залізничного транспорту ім. академіка В. Лазаряна, 2017. https://er.knutd.edu.ua/handle/123456789/9332.

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The article analyses the development of technologies used in construction. It is a short retrospective review of achievements in this sphere: from Great Pyramid of Giza to 3D printers’ usage for construction materials.
Стаття є аналізом розвитку технологій, що використовуються в будівництві. Це короткий ретроспективний огляд досягнень в цій області: від великої піраміди Гізи до використання 3D-принтерів для створення будівельних матеріалів.
Статья представляет собой анализ развития технологий, используемых в строительстве. Это короткий ретроспективный обзор достижений в этой области: от великой пирамиды Гизы до использования 3D-принтеров для создания строительных материалов.

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Dimitrov, D., Beer N. De, and T. Centner. "Product and process innovations by means of rapid technologies." Journal for New Generation Sciences, Vol 4, Issue 1: Central University of Technology, Free State, Bloemfontein, 2006. http://hdl.handle.net/11462/487.

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Published Article
Over the past few years, methods of layered manufacturing (LM) have advanced substantially to the point where they now provide vital strategic benefits to various organisations. One area of application where LM technologies have begun to reach a critical mass is in the development and production of high-performance tooling in different forming processes. With these tooling capabilities now available, the next challenge becomes the development of optimal process chains to minimise lead times and production costs, while still ensuring high quality of castings. The relevant issues that influence where a break-even point will be between different process chains and thereby also the point of selection between such optimal process chains according to different situations include among others:

the size of production runs,
part size and complexity, and
the cast materials involved.

This paper reflects some of the experiences gained from an investigation towards developing a set of generic rules (guidelines) for the design of optimal process chains for sand casting prototypes of automotive components using LM methods, and more specifically the 3D Printing process.

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Смирнов, Василь Анатолійович, Василий Анатольевич Смирнов, Vasyl Anatoliiovych Smyrnov, D. O. Varukha, Іван Володимирович Павленко, Иван Владимирович Павленко, Ivan Volodymyrovych Pavlenko, Олександр Олександрович Ляпощенко, Александр Александрович Ляпощенко, and Oleksandr Oleksandrovych Liaposhchenko. "Implementation of additive technologies for the complex development of buildings and structures by means of 3D printing." Thesis, Sumy State University, 2017. http://essuir.sumdu.edu.ua/handle/123456789/66719.

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An uninterrupted movement towards the implementation of the basic principles of the 4th industrial revolution, well-known as “Industry 4.0” [1], requires an application of 3D printing to create buildings and structures that fundamentally changes our traditional viewpoint.

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Guerra, Sánchez Antonio. "Contribution to bioabsorbable stent manufacture with additive manufacturing technologies." Doctoral thesis, Universitat de Girona, 2019. http://hdl.handle.net/10803/667867.

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The main motivation of this work was to analyse the feasibility of the current stent’s manufacturing process to produce the new bioresorbable stents (BRS) as well as study new manufacturing methods. Fibre Laser Cutting (FLC) has been selected because is the current manufacturing process for stents, and 3D-Printing (3DP) because its capability to process different types of materials for medical applications and their economic aspects. Stents have been selected for being one of the most implanted biomedical device in the world. The thesis focuses on improve the bioresorbable stent’s manufacturing processes, establishing relationships between the process parameters and the key stent aspects, namely, precision, mechanical properties, and medical properties, and reduce the costs derived of the manufacturing process
La principal motivació d'aquest treball va ser analitzar la viabilitat del procés de fabricació de stent actual per produir els nous stents bioabsorbibles (SBA), així com estudiar noves maneres de fabricar-los. El tall làser de fibra (TLF) ha estat seleccionat perquè és el procés de fabricació actual per stents i L´impressió 3D (I3D) perquè té la capacitat de processar diferents tipus de materials per a aplicacions mèdiques i els seus aspectes econòmics. Stents ha estat seleccionat per ser un dels dispositius mèdics més implantats del món. La tesi es centra en la millora dels processos de fabricació de stent, establint relacions entre els paràmetres del procés i els aspectes clau de stent, precisió, propietats mecàniques i propietats mèdiques i reduir els costos derivats d'aquest procés de fabricació

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McAllister, Walter Elliot. "A Critical Review of Multi-Phase Materials and Optimization Strategies for Additive Printing Technologies." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/76789.

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The focus of this thesis is the critical review of Additive Printing (AP) or 3D-printing, and optimization strategies for the introduction of new materials. During the course of tenure, four classes of solids were investigated to determine the hurdles presented from each system. Specifically, the investigation developed techniques for optimization of ink production, green-film deposition, and laser sintering parameters surrounding the Optomec AJP system (AJP). In the assessment, statistical experimental design, analysis and material characterization techniques have been utilized. Final recommendations disseminate current best practices for new ink and material development, along with factor analysis of input variables for phase and material properties, along with insights for future research of these systems. The first chapter provides a general introduction to the field of AP. The second chapter focuses specifically on Optomec aerosol-jet process (AJP) techniques, and expands the discussion to process parameters, information concerning the fabrication/characterization procedure followed for each system, and includes: a detailed description of the materials investigated. This is important because printing parameters, optimization, and approach may be divergent for optimization within each strain; and is meant as an aid to resolve some technical issues for future investigators. The third chapter is fully dedicated to the results concerning the fabrication and the characterization of amorphous boron powder to film. Chapter four discusses future research options, ideas and directions. Appendices are provided for any which wish to investigate the orthogonal arrays used, or the combinatorial effects resulting in the attributes of the material system final products.
Master of Science

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De, Beer Neal. "An investigation towards developing capability profiles of rapid prototyping technologies with a focus on 3D-printing." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/53724.

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Thesis (MEng)--University of Stellenbosch, 2004.
ENGLISH ABSTRACT: Rapid prototyping (RP) technologies have expanded vastly over recent years. With the advent of new materials along with new processes, each technology has been contributing to the diversities in different fields of application for the growing technologies. In the course of improvement, it is however critical to understand exactly what the capability of each individual technology is in order to compare future improvements, or even to compare current processes and technologies. The objective of this research has been to develop capability profiles of prominent RP technologies: 3D-Printing (3DP), Selective Laser Sintering (SLS), and Laminated Object Manufacturing (LOM) - in which different characteristics of each technology are measured and quantified. A capability profile may be regarded as a set of building blocks that give a representation of the RP technology's ability and is defined by quantifying the following characteristics: Accuracy (both dimensional- and geometrical accuracy) Surface finish measures Strength and elongation Build time, and Cost The significance behind developing capability profiles lies in the need to more accurately describe and compare each of the different processes - especially Z Corporation's 3DP, since although this process is regarded as very capable in many areas, little has been published to substantiate this opinion. When users of these technologies are pushing the limits of their machines, it becomes critical to know exactly what these boundaries are in order to know with some measure of certainty that they will be able to fulfil a certain customer demand or expectation. For South Africa in particular, the industry's growing interest in rapid prototyping is triggering inevitable questions as to whether a certain RP technology can produce the desired solutions to their problems. The South African industry's growing awareness about rapid prototyping is opening new doors for better solutions to new and existing problems - but ultimately, before investing money, customers want to know if RP is going to meet the standards needed to solve their solutions. On a more general level, this study can also be seen to bear significance in contributing to research in what has become known as rapid manufacturing (RM). This term is defined as the manufacture of end-use products using additive manufacturing techniques. RM must guarantee long-term consistent component use for the entire product life cycle or for a defined minimal period for wearing parts [1]. However, before it is possible to guarantee long-term consistency of components, one must first ensure consistency of the process. Once a process is consistent, the next question becomes: What is it capable of doing consistently? This study aims to answer this question for the three processes (3DP, SLS and LOM) mentioned earlier. In doing so, this study and its development of capability profiles, seeks to contribute and be of value in both academic circles as well as for industry partners and system manufacturers.
AFRIKAANSE OPSOMMING: Snelle Prototipering (SP) tegnologieë het die afgelope jare ongelooflike groei ondervind. Met die ontwikkeling van nuwe materiale tesame met nuwe prosesse, het elke tegnologie bygedra tot 'n diversiteit in moontlike toepassings vir 'n verskeidenheid van velde. Met 'n mikpunt van aaneenlopende verbetering, is dit egter krities om te verstaan presies wat elke individuele tegnologie se vermoëns is. Dit maak dit dan moontlik om toekomstige verbeteringe te vergelyk, of om selfs huidige prosesse met mekaar te vergelyk. Die doel van hierdie navorsing was om vermoënsprofiele van prominente SP tegnologieë te ontwikkel: 3D-Printing (3DP), Selective Laser Sintering (SLS) en Laminated Object Manufacturing (LOM) - waarin verskillende karaktereienskappe van elke tegnologie gemeet en gekwantifiseer word. 'n Vermoënsprofiel mag beskou word as 'n stel boustene wat 'n weerspieëling gee van die SP tegnologie se vermoë en word gedefinieer deur die kwantifisering van die volgende karaktereienskappe: Akkuraatheid (beide dimensionele- en geometriese akkuraatheid) Oppervlakgehalte metings Treksterktes en verlengings Bou- of vervaardigingstye, en Kostes Die rede waarom dit belangrik is om vermoënsprofiele te ontwikkel berus by die behoefte om die verskillende prosesse met meer akkuraatheid te beskryf en te vergelyk - veral Z Corporation se 3DP. Alhoewel hierdie proses algemeen beskou word as baie bevoeg in vele areas, is min informasie al gepubliseer om hierdie opinie te ondersteun. Wanneer gebruikers van hierdie tegnologieë hul masjiene tot die limiete druk, begin dit krities raak om presies te weet wat daardie grense is, sodat hulle met 'n sekere mate van sekerheid sal kan sê of hulle sal kan voldoen aan kliënte se behoeftes of verwagtinge. Die Suid-Afrikaanse industrie se belangstelling in SP tegnologieë begin al hoe meer groei, en daarmee saam, begin vrae ontstaan tot watter mate snelle prototipering wel werkbare oplossings kan produseer vir hul probleme. Hierdie groeiende bewustheid van die Suid-Afrikaanse industrie begin dus ook nou nuwe paaie openbaar vir beide nuwe en ou probleme - maar uiteindelik, voordat kliënte egter bereid sal wees om geld te belê, sal hulle wil weet of snelle prototipering die standaarde gaan behaal wat nodig sal wees om juis hierdie oplossings te verwesenlik. Op 'n meer breë vlak, beoog hierdie studie om ook 'n bydrae te maak in die groeiende navorsingsveld van snelle vervaardiging (SV). Hierdie is 'n term wat gedefinieer word as die vervaardiging van endgebruiker produkte, met die benutting van byvoegings-vervaardigings tegnieke. SV moet versekering bied vir komponente se werkverrigting op die lange duur vir die hele produk se lewenssiklus, of ten minste vir 'n gedefinieerde minimale tydperk in die geval van slytasie-parte [1]. Maar voordat dit moontlik sal wees om hierdie versekering te bied, moet mens eers die versekering kan bied van 'n proses se werkverrigting. Wanneer die prosesse betroubaar en deurlopende resultate lewer, word die volgende logiese vraag gestel: Wat presies, is hierdie proses in staat om betroubaar te lewer? Hierdie studie beoog om juis hierdie vraag te beantwoord vir die drie prosesse (3DP, SLS en LOM) wat vroeër genoem is. Dienooreenkomstig, met die ontwikkeling van vermoënsprofiele van hierdie prosesse, behoort hierdie studie van waarde te wees vir beide akademici, sowel as industrie-lede en vervaardigers van SP tegnologieë.

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Radtke, Carsten [Verfasser], and J. [Akademischer Betreuer] Hubbuch. "Implementation of Novel Technologies in HTPD - (Bio-) 3D-Printing and Microfluidics / Carsten Philipp Radtke ; Betreuer: J. Hubbuch." Karlsruhe : KIT-Bibliothek, 2018. http://d-nb.info/1199352322/34.

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Heimonen, Johanna. "Synthesis of a polar conjugated polythiophene for 3D-printing of complex coacervates." Thesis, Linköpings universitet, Laboratoriet för organisk elektronik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-177396.

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The aim of this thesis was to synthesize a functionalized polar conjugated polythiophene that could be (3D-) printed into form-stable structures for bio-interfacing. The material design rationale aimed for a water-processable polymer that had the capability of electronic and ionic conduction, by using a thiophene backbone and oligoethylene side chains. Functionalization of the oligoethylene side chains with carboxylate groups created a polyanion, which allowed for a bio-inspired approach to combine printability and form-stability through formation of complex coacervates. The synthesis of the conjugated monomer and polymer was optimized to provide a more sustainable and material efficient synthesis route. Combined structural analysis with 1H-NMR, FT-IR and UV-vis revealed successful synthesis of the target polymer. Spectro electrochemistry revealed that the polymer was optically and electrochemically active in both the protected and deprotected form. The obtained material is processable from water, and initial tests revealed that crosslinking can be achieved through formation of acid dimers, ionic crosslinks with Ca2+ ions and complex coacervation with a polycation.

Examensarbetet är utfört vid Institutionen för teknik och naturvetenskap (ITN) vid Tekniska fakulteten, Linköpings universitet

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Hernandez, Benjamin R. Jr. "An investigation into the use of 3D scanning and printing technologies in the Navy Collaborative Product Lifecycle Management." Thesis, Monterey, California: Naval Postgraduate School, 2013. http://hdl.handle.net/10945/38945.

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Approved for public release; distribution is unlimited.
The Navy Collaborative Product Lifecycle Management (CPLM) is notional for the construction of scenarios for this thesis. Theoretically, CPLM works with suppliers to design, manufacture, and distribute parts and equipment required for routine operations. However, there are some issues with this, including the length of time required for designing parts and supply chain interruption, which means that there is a need to improve the process. The option for improvement explored in this research is the use of three-dimensional (3D) scanning (3DS) and printing (3DP) technologies, which respectively offer the ability to generate a computerized shapefile from a 3D object and then to transform this shapefile back into a physical object. 3DS and 3DP technologies are widely used in product design, as it enables rapid production of prototypes, including functional prototypes. 3DP can also be used for rapid manufacturing on a small scale (such as production of spare parts) or large scale (especially using lost-wax casting). These technologies do have a potential benefit for the Navys CPLM process, because it could help solve problems like supply chain disruption, immediate replacement of parts, and the length of the product development lifecycle. However, 3D technologies can be expensive, and in some cases may not be accurate enough for use. In this research, three distinct scenarios for implementation of 3D technology in the CPLM cycle are examined, including prototyping, small-scale shipboard manufacturing, and large-scale rapid manufacturing. The findings of the research suggest that at the present time the use of 3DS and 3DP technologies is best suited to the design stages of the research, although the rapid manufacturing application also has promise. The shipboard application, although it would resolve a supply chain problem, is too expensive and complicated to be effective at this time.

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Rodrigo, Miranda. "A Comparative Study of Strength and Stiffness of Thin-Walled Specimens Fabricated By FDM and 3D Printing Technologies." BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3349.

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Rapid Prototyped part failure constitutes a major issue for both RP providers and customers. When parts fail the reputation of the vendor is heavily deteriorated, customer dissatisfaction increase and replacement of the broken parts is often necessary to avoid the loss of future business. Product design teams often run into situations where Rapid Prototyped parts are not able to withstand shipping and handling and delivered broken or while demonstrating and examining the parts. When done in the face of customers this builds a perception of poor quality and lack of aptitude on the design group as well as the RP processes. The rapid advance of the RP industry and technology has led users to employ RP parts for structural applications where the need to understand in great detail and accuracy the mechanical behavior of the product and its individual components is greater than ever. Models built on Rapid Prototyping (RP) equipment are most often made from polymers which frequently have mechanical properties that are inferior to those manufactured by traditional methods such as thermoforming or injection molding. Not only are the mechanical properties of RP models typically low, they are usually, at least in thin sections, directly dependent on the section or wall thickness of the models. This dependence of strength on wall thickness makes it difficult to predict a proper wall thickness for RP models, even when nominal values of material strength are known. The purpose of this work is to present and compare measured values of tensile strength and stiffness as a function of wall thickness for three RP processes and materials. These properties will assist designers estimating adequate minimum wall thicknesses for models built by the three processes. The three RP technologies included in the scope of this research are: Z Corporation (powder with polymer binder layup), Fuse Deposition Modeling and PolyJet Layup (Objet). The findings of this study establish that tensile strength and stiffness values are dependent upon wall thickness, building orientation and direction of the applied force of specimens created with the methods in consideration. It was also determined that the correlation between thickness and strength for all processes is non-linear. Due to these results a single tensile strength and modulus value for each material and all wall thicknesses do not accurately represent their behavior. However, these results will allow a designer to understand the relationship between the wall thickness and using the data provided in this work be able to model and then fabricate adequate 3D prototypes.

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Maravola, Michael. "Low Coefficient of Thermal Expansion Composite Tooling Manufactured via Additive Manufacturing Technologies." Youngstown State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ysu154704993501967.

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Bisognin, Aimeric. "Évaluation de technologies organiques faibles pertes et d’impression plastique 3D afin de contribuer au développement de solutions antennaires innovantes dans la bande 60 GHz – 140GHz." Thesis, Nice, 2015. http://www.theses.fr/2015NICE4120/document.

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L’émergence des applications mobiles accessibles depuis un smartphone provoque une très forte augmentation du trafic de données transitant sur les réseaux mobiles. L’augmentation de la capacité du réseau et de la rapidité des connexions sont autant de points cruciaux que les nouvelles générations de réseau mobile devront adresser afin de répondre à la demande des utilisateurs. L’une des solutions viables pour augmenter la capacité du réseau mobile consiste à le densifier afin de permettre la réutilisation des fréquences en déployant des stations de base consommant une faible puissance et couvrant de petites surfaces (les "small cells"). Ce mode de déploiement massif en "small cells" constitue un défi majeur pour le réseau de backhaul afin de reconnecter chacune de ces "small cell" au cœur de réseau. De plus, avec l’évolution du réseau de backhaul vers une architecture de type Centralized Radio Access Network (CRAN), des technologies sans fil pouvant supporter des débits supérieurs à 10Gbit/s seront requises. Étant donné la maturité des technologies silicium au-delà de 100GHz, la bande 116-142GHz semble être un candidat idéal pour établir des communications point à point supérieures à 10Gbit/s et très faible consommation DC. Dans cette thèse, plusieurs solutions d’antennes-lentilles et réflecteurs fonctionnant à 60, 80 et 120GHz sont explorées pour des systèmes WLAN/WPAN et backhaul. Afin de minimiser le coût de la solution antennaire, nous évaluons des technologies d’impression 3D pour la fabrication des lentilles et des réflecteurs, ainsi que des technologies utilisant des matériaux organiques à faibles pertes pour la fabrication des antennes-sources planaires
The improvement of the capabilities of wireless communication devices (smartphone, tablets …) which require higher and higher data rate, leads to a significant increase of the data traffic needed by each end user. This strong consumer demand for higher data-rate and coverage is stressing a lot the capacity of existing cellular networks. In order to cope with this challenge, one of the most promising solution consists in a network densification based on the deployment of low-power and short-range-radio-coverage base stations (small cells). The development of high data-rate and low power wireless fronthaul and backhaul technologies is a key requirement to enable the deployment of those future small cells (since associated civil works costs generally prevent the use of optical fiber solutions). So far, the wireless industry has been investigating the use of 60 and 80 GHz frequency bands in order to develop low-cost higher than 1Gbit/s backhaul solutions. It is expected that higher data-rate > 10 Gbit/s will be required for fronthaul communications. The broad bandwidth available around 120GHz (116-142GHz) would enable to reach such data rates while lowering the DC power consumption. In this thesis, we develop several lens and reflector antennas operating at 60, 80 and 120GHz for WLAN/WPAN and fronthaul/backhaul networks. In order to minimize the cost of those solutions, we evaluate 3D-printing technologies for the fabrication of the lenses and the reflectors as well as industrial low loss organic packaging technologies for the fabrication of planar antenna-source

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Blom, Martina, and Sara Landstedt. "Granskning av 3D-printingens möjligheter vid utformning av byggnader." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Byggnadsteknik och belysningsvetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-31677.

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Purpose: There is today limitations of what is possible to design and in fact produce. In industrial construction the focus is on standardization which impedes an individual design form, which can be considered an architectural quality. The potential of 3Dprinting is growing, which is benefitting design freedom. The goal was to evaluate how 3D-printing in Sweden today could increase architects possibilities at the design process and be production adapted. Method: In a case study at Tengbom in Jönköping, interviews were included with three architects. In addition, a literature review, a telephone interview and a focus group interview formed the basis of the collected material. As an initial phase, a focus group interview was conducted, which resulted in the actors’ opinions about 3D-printing. The architect interviews contributed with high credibility regarding architectural qualities, which together with the other collection methods gave answers to the studies questions. Findings: The study shows that it is possible to print building components in Sweden. However it is not possible, with 3D-printing, to produce entire buildings. It can be shown that there are obstacles for the introduction of the technology, such as economy, Swedish laws and lack of knowledge. These should be reviewed to allow 3D-printing as a manufacturing method. With Rapid Ornament Production larger architectural qualities will conduce to, where 3D-printing allows unique solutions. Solutions no other technology can achieve. Implications: Customized and varied buildings can be achieved thanks to 3D-printing. Building components such as light weight walls, ornaments and details can be produced in Sweden today. One advantage of 3D-printing as a technology, is that it provides greater freedom between design and production. For further development of 3Dprinting a greater knowledge is recommended for industry stakeholders, regarding the drawing tools as well as the 3D-printing technology. Limitations: The result is applicable to architects, working at architectural offices similar to Tengbom in Jönköping. There have not been deeper studies regarding of printing technologies, finances, materials, time or law. A case study as research strategy entails an interpretation of the opinions, which limits the generalization of the results. Keywords: 3D-printing, design, production, architectural qualities, possibilities, limitations, industrial construction.
Syfte: Det finns idag begränsningar för vad som är möjligt att utforma och faktiskt producera. I industriellt byggande ligger fokus på standardisering som försvårar ett individuellt formspråk, vilket kan anses vara en arkitektonisk kvalitet. Potentialen för 3D-printing växer, vilket gynnar utformningsfriheten. Målet var att utvärdera hur 3D-printing i Sverige idag skulle kunna öka arkitektens möjligheter vid utformning och vara produktionsanpassat. Metod: I en fallstudie på Tengbom i Jönköping, ingick intervjuer med tre arkitekter. Utöver detta har en litteraturstudie, telefonintervju och en fokusgrupp legat till grund för insamlat material. Som ett inledande skede genomfördes en fokusgrupp, vilken resulterade i aktörers åsikter om 3D-printing. Arkitektintervjuerna bidrog med hög trovärdighet gällande arkitektoniska kvaliteter, vilket tillsammans med övriga insamlingsmetoder gav svar på studiens frågeställningar. Resultat: Studien visar att det är möjligt att skriva ut byggkomponenter i Sverige. Dock är det inte möjligt att med 3D-printing tillverka hela byggnader. Det kan påvisas att det finns hinder för införandet av tekniken, så som ekonomi, svensk lagstiftning samt bristande kunskap. Dessa bör ses över för att möjliggöra 3D-printing som tillverkningsmetod. I och med Rapid Ornament Production kan större arkitektoniska kvaliteter främjas, där 3D-printing möjliggör unika lösningar. Lösningar ingen annan teknik kan åstadkomma. Konsekvenser: Kundanpassad och varierad bebyggelse kan åstadkommas tack vare 3D-printing. Byggkomponenter så som, lättväggar, ornament och detaljer kan tillverkas i Sverige idag. En fördel med 3D-printing som teknik, är att den ger större frihet mellan projektering och produktion. För vidare utveckling av 3D-printing rekommenderas ökad kunskap för branschens aktörer gällande ritverktygen samt 3D-printings-tekniken. Begränsningar: Resultatet är applicerbart för arkitekter, verksamma vid arkitektkontor av liknande storlek som Tengbom i Jönköping. Det har inte genomförts djupare studier gällande utskriftstekniker, ekonomi, material, tid eller juridik. Fallstudie som undersökningsstrategi innebär en tolkning av åsikter, vilket begränsar generaliseringen av resultatet. Nyckelord: 3D-printing, utformning, produktion, arkitektoniska kvaliteter, möjligheter, begränsningar, industriellt byggande.

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Kenney, Michael E. "Cost reduction through the use of additive manufacturing (3D printing) and collaborative product life cycle management technologies to enhance the Navy's maintenance programs." Thesis, Monterey, California: Naval Postgraduate School, 2013. http://hdl.handle.net/10945/37648.

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In order to keep its ships and aircraft in an operational status, the U.S. Navy must have access to the parts necessary for repair. Current supply warehouses do not always carry the required repair parts; therefore, when parts are unavailable, the Navy must either look to traditional acquisition sources or utilize manufacturing capabilities available at depot and intermediate maintenance activities. This thesis examines the potential cost benefits of incorporating additive manufacturing (AM), commonly known as 3D printing, and collaborative product life cycle management (CPLM) software into these maintenance activities. The research uses the knowledge value added (KVA) methodology to analyze modeled data and capture and quantify the benefits of introducing AM and CPLM technologies into Navy maintenance activities. This proof of concept was developed to apply AM and CPLM to as-is and several to-be maintenance process models in order to measure the potential benefits. By introducing AM and CPLM technologies into the current manufacturing process, the notional scenario showed positive results and suggests a significant reduction to cycle time and a potential cost savings of $1.49 billion annually.

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Schliemann, Marvin. "Implications of Logic Multiplicity During Early Phases of Competence Center Formation : A Case Study of 3D Printing in Life Sciences." Thesis, Uppsala universitet, Industriell teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-412959.

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Great challenges often require the combined strength of various actors. Especially in areas that are shaped by fast technological development such as the application of additive manufacturing (AM) in life sciences, the interplay of different fields of expertise, including experts from industry, academia and government, is needed. While the collaboration of diverse actors can constitute a vast potential for innovations, it also entails a major challenge to negotiate among diverse individual interest, backgrounds, beliefs, and value systems. One field of research that can help to understand the consequences of such differences in the interests and beliefs in organizational settings is the institutional logics perspective. Institutional logics account for broader institutional value systems that guide actors’ cognition and actions. When organizations embody multiple logics, scholars speak of logic multiplicity. However, the consequences for organizational functioning that arise from logic multiplicity are still discussed among scholars, ranging from an enhanced innovativeness, to an increased conflict potential and organizational dismiss. In order to better understand logic interaction and its implications for organizational functioning, an embedded-case study was conducted. The embedded-case study focused on AddLife at Uppsala University, a competence center in its early phases of formation which is concerned with the advancement of applications of AM in life sciences. Based on semi-structured interviews and documentational data, three different logics were captured for three main stakeholder groups in AddLife. Further, the interaction of these logics during the early phases of competence center formation was analyzed, corroborating the role of logic compatibility (whether logics imply consistent goals). This study’s findings suggest that common goals have been found in AddLife, but some differences regarding the different logics’ implied goals remain, stressing the role of active mediation. Further, the study suggests that building strong intra-organizational ties is pivotal during the early phases of competence center formation, proposing a framework that encompasses three main approaches to build such ties. The first approach is to create a sense of community, including to reinforce synergies, to ensure engagement, and to connect projects. The second approach is to establish an open communication flow which comprises to clarify roles, to encourage asking questions, and to match expectations. Finally, the third approach is to organize personal meetings in order to establish relationships in the first place and to enable discussions.

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Nachabe, Nour. "Évaluation des technologies d'impression 3D pour le développement d'antennes directives à large bande passante pour les liaisons backhaul en bandes millimétriques V et E." Thesis, Université Côte d'Azur (ComUE), 2018. http://www.theses.fr/2018AZUR4118/document.

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Face à la demande croissante de débits de données de plus en plus élevées, l’une des principales solutions proposées par la 5G est de densifier le réseau en y intégrant notamment de nouvelles « Small cells ». La réorganisation de l’architecture du réseau mobile pour s’adapter à l’intégration poussée de ces Small cells, fait naître la problématique de la connexion backhaul entre les stations de bases desservant les Small cells et le cœur de réseau. Ainsi, des liaisons backhaul de plusieurs Gb/s de données sont nécessaires pour pouvoir assurer un débit de données d’au moins 100Mb/s à l’utilisateur qui est l’un des objectifs fixés pour la 5G. Les solutions de connexion backhaul sans fils ont un avantage indiscutable face aux coûts de déploiements de fibres optiques qui sont très élevés. Pour augmenter la capacité spectrale des liaisons sans fils, l’utilisation des fréquences millimétriques au-delà de 6 GHz caractérisées par des larges bandes passantes sera prochainement discutée pour la 5G durant le World Radiocommunication Conference 2019. Parmi ces fréquences, les bandes V (57-66GHz) et E (71-76 GHz et 81-86 GHz) ont un intérêt indéniable grâce aux larges bandes passantes disponibles ainsi qu’aux conditions de licenciement peu exigeantes. Les travaux développés dans cette thèse consistent à concevoir des antennes directives à large bande passante permettant d’établir les liens backhaul point-à-point sans fils (LoS). En exploitant les technologies de fabrications à faibles coût telles que l’impression 3D et Printed Circuit Board (PCB) sur des substrats FR4, la conception de deux types d’antenne directives a été étudiée à savoir des antennes lentilles et des antennes réseaux
In order to address the ever-increasing demand of higher data rates, adding small cells to the existing macrocells infrastructure is one of the most important milestones of the 5G roadmap. With the integration of small cells and the re-organization of the network topology, backhaul bottleneck is the main challenge to address in the near future. Facing the costs of deployments of fiber optic connections, point-to-point wireless backhaul links using millimeter wave (mmW) frequencies are gaining prominence. 5G future frequencies, to be discussed under the World Radiocommunication Conference 2019 (WRC-19) open-up the way towards mmW frequency band where large bandwidths are naturally available. The high bandwidths available at these frequencies enable several Gbps data rate backhaul links, which is un utmost necessity to respect the 100 Mbps user-experienced data rate promised by the 5G standard. Millimeter-wave frequencies in V and E-bands unlicensed/light licensed spectrum are considered as primary candidates for backhaul links. In addition to the light license regime, the high free space path loss experienced at these frequencies is rather beneficial to limit the interference between small cells links. Moreover, the high available bandwidths at V and E-bands enable to achieve multi Gb/s links without using complex modulation schemes. In this thesis, we focused our research study on developing high gain wide-band antennas usable in point-to-point backhaul links in a Line of Sight (LoS) context. Leveraging cost-efficient technologies like 3D printing and Printed Circuit Board (PCB) on FR4 substrates, we studied two high-gain antenna types: lens antennas and flat array antennas

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Crisanti, Roberto. "Laser Direct Energy Deposition per la manifattura additiva: caratterizzazione del processo e prove sperimentali." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.

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Studio condotto presso il Dipartimento di Ingegneria Industriale dell’Università di Bologna su un processo di Laser Direct Energy Deposition, o Laser Cladding, e sulla sua caratterizzazione, avente come fine ultimo quello di realizzare pezzi massicci a base rettangolare dotati di una morfologia esterna regolare e al contempo privi di difetti macroscopici all’interno, quali porosità o zone con mancata fusione del materiale d’apporto. Nella prima parte dello studio sono stati presi in esame i principali parametri di processo, ovvero la potenza della sorgente laser e la portata di polvere, e l’influenza che essi hanno sulle caratteristiche geometriche del deposito (profondità di penetrazione, altezza, larghezza, grado di diluizione, area del deposito e del rinforzo, ampiezza media della ZTA, percentuale di porosità). Tale studio si è basato sull’osservazione ed analisi al microscopio di singoli cordoni di deposizione, realizzati variando la portata di polvere la potenza del laser, a parità di velocità di avanzamento. La seconda parte si basa sull’analisi dei risultati delle prove condotte con lo scopo di realizzare dei campioni massicci a base rettangolare: si sono studiati gli effetti che variazioni dei parametri di processo e della strategia di scansione hanno avuto sulla morfologia finale dei pezzi e sulle loro caratteristiche interne (porosità, zone con mancata fusione). Si sono confrontate due strategie di deposizione, la strategia con ritorno della testa a laser spento (laser OFF) e la strategia con ritorno della testa a laser acceso (laser ON). Tale studio ha permesso di concludere che la strategia con ritorno laser ON risulta essere preferibile in quanto non solo consente di ottenere un risparmio in termini energetici, di tempo e di quantità di polvere utilizzata, ma anche di realizzare dei pezzi massicci che rappresentano il miglior compromesso ottenuto tra una morfologia esterna uniforme e delle buone caratteristiche interne, con una densità prossima al 100%.

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Sandgren, Simon, and Annette Wolff. "Implementing Additive Manufacturing in Cardiology : A qualitative study of barriers and facilitators from a managemental point of view." Thesis, Uppsala universitet, Institutionen för samhällsbyggnad och industriell teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-413307.

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Additive Manufacturing (AM) is a fast-developing technology, that despite itspotential is yet to be applied by the mainstream healthcare market. Comparedto other clinical areas where AM is applied, cardiology has a negligible marketshare, why this thesis aimed at identifying barriers and facilitators for AMimplementation, as well as presenting a framework with factors to considerwhen attempting to implement AM. A literature review outlined aspects currently considered in literature, inrelation to the barriers and facilitators of implementing AM in cardiology. Toidentify barriers and facilitators to AM implementation in cardiology, and tocomplement the literature review, two exploratory case studies were carriedout, which had a comparative design. The case studies took place in Sweden,whereof one has already implemented AM in cardiology, and the other one hasnot. Purposive sampling was applied to choose the two involved hospitals, whileconvenience sampling and snowball sampling were used for selecting interviewparticipants. The findings were analyzed using a thematic analysis. Results show that barriers and facilitators can act on an individual,organizational, and industrial level. Barriers and facilitators were divided intothe themes Management, Technology, Network, Behavior, and Market. Aspectsfalling under the theme Management were mentioned most frequently amongthe respondents, suggesting that such barriers and facilitators play a significantrole in implementing AM, while findings placed in the Network and Behaviortheme respectively were not previously addressed in literature. Barriersinclude, among others, low involvement of leaders, little cross disciplinarycollaboration, and lack of innovation resources in health care. Facilitatorsinclude, among others, having an innovation culture that supports initiation ofprojects, providing an easy and intuitive system for ordering a 3D model, andpromoting the technology among potential users. Concluded is that AM implementation faces numerous barriers and facilitatorswhich should be considered before an implementation endeavor. Addressingthese on an individual, organizational, and industrial level most likely facilitatesthe process of AM implementation, leading to a successful and sustainablechange in the organization.

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Sekerka, Vít. "Výroba dílů technologií DMLS a jejich porovnání s jinými konvenčními technologiemi z hlediska ekonomické náročnosti." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-229969.

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This diploma thesis presents a technology based on the gradual smelting of fine layers of metal powder by using a laser beam. It explains and describes basic terminology related to the Rapid Prototyping technology, its division and practical usage. A part of the thesis is also the fabrication of several prototype parts by Direct Metal Laser Sintering including the economical comparison of their fabrication with other conventional technologies.

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Macháček, Marek. "Návrh variantní výrobní technologie oběžného kola ventilátoru." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-451201.

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The thesis considers a change in the manufacturing technology of a fan impeller from welding to 3D printing. The wish of the manufacturer was to investigate if such a change is possible and financially profitable and decide on a further approach to manufacturing. Models were created using information from the manufacturer and using them, conditions for manufacturing the impeller in the 1:1 ratio were derived. Based on the new technological process and the experience from prints a new price calculation for the fan impeller using 3D printing was created.

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Šebánek, Jan. "VYUŽITÍ 3D TECHNOLOGIÍ VE VEŘEJNÉM PROSTORU." Doctoral thesis, Vysoké učení technické v Brně. Fakulta výtvarných umění, 2016. http://www.nusl.cz/ntk/nusl-240509.

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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.

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Spišák, Lukáš. "Analýza plastových materiálů vyrobených aditivní technologií 3D tisku." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-417125.

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The diploma thesis deals with the influence of colouring additives and setting of the process parameters of 3D printing on the mechanical and surface properties of samples made of PLA material. The work describes the process of filament production, as well as the printing of normalized samples on a 3D printer using the additive method Fused Deposition Modeling. The impact of 3 types of colouring additives is evaluated on the basis of tensile test, hardness test and surface analysis. The evaluated quantities are primarily tensile strength, hardness, surface texture, roughness and corrugation. The work also evaluates the influence of the percentage of sample filling, the direction of the fibres of the inner filling and the orientation of the samples in the printing chamber of the 3D printer on the mechanical properties. The results are evaluated on the basis of the tensile test and the evaluated quantities are mainly the tensile strength, the ultimate stress and the modulus of elasticity in traction. The work is completed by evaluating the results and overall recommendations for filament manufacturers and users.

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Zucchini, Davide. "Design and realization of an instantaneous concentration measurement system for wind tunnel applications." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/23540/.

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The aim of this project work is the design and realization of an instantaneous concentration measurement system to be used with binary gas mixtures. The design is focused on the simplicity of the set up and on its compactness, and it is specifically intended to be used in wind tunnel applications. The outcome of the design process for the specified system is an aspirating hot-wire probe based on a polypropylene 3D printed body and a simple single wire sensor. Specifically, a 3D printing machine based on the Material Jetting (MJ) technology was used for the probe manufacturing. One of the most important design features is the possibility to get access to the wire through the removal of a single probe component, which is a nearly effortless operation. This feature allows to repair the broken wire sensor without the need of substitute the whole probe. From these design specifications it could be understood that due also to its dimensions, the probe must be handled with care, and it cannot operate inside hot flows or uncontrolled flow temperature and pressure conditions. It was not possible to test the probe behaviour in presence of flows with composition variations due to the lack of the necessary instrumentation to perform this kind of experiments. Nonetheless, the design effectiveness could be confirmed by verifying that the hot-wire signal remained constant when the probe was exposed to a variable speed constant composition flow. This proved the probe insensitivity to external flow speed, and it opened the possibility to further testing sessions involving gases.

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Táborský, Pavel. "Využití aditivní technologie pro výrobu dílu pro automobilový průmysl." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-417127.

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The diploma thesis deals with the production process of optical part of headlamp module produced by additive technology. The thesis contains the characteristics of headlamp, current manufacturing technology and description of additive manufacturng methods. The practical part is focused on the production of a reflector using 3D printing. The conclusion of the thesis is dedicated to the measuring of light output and its evaluation.

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Robl, Jan. "Využití kovové aditivní technologie při výrobě oběžného axiálního kola turbínového motoru pomocné energetické jednotky." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-417561.

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The thesis deals with the possible use of additive technology in the production of strong thermally exposed components of turbine engines. The first part of the thesis is dedicated to the issue of processing heat-resistant materials by SLM method, introduction of conventional production of selected part and outline of currently used progressive methods in precision casting technology. These theoretical findings are further applied in the practical part of the thesis, which deals with the analysis of mechanical properties of cast and printed material IN 939. Experimental part also includes production of the blisk of the first stage turbine of the auxiliary power unit S5L by SLM additive technology. The thesis also includes analysis of fracture surfaces and metallographic analysis of samples using light and scanning electron microscopy. The thesis ends with the evaluation of the achieved results.

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Delage, Anthony. "Technologie aérosol appliquée à l'intégration 3D et aux composants hyperfréquences." Thesis, Limoges, 2019. http://www.theses.fr/2019LIMO0113.

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Ces travaux de thèse portent sur la mise au point de la technologie Aérosol Jet printing (AJP) pour réaliser des composants hyperfréquences dans la bande des fréquences millimétriques et pour répondre à des problématiques d’intégration 3D de composants. Le premier chapitre est consacré à une étude bibliographique pour comparer les différentes technologies additives existantes sur le marché afin de positionner l’AJP par rapport à l’état de l’art. Le second chapitre est consacré à la sélection et à la caractérisation de matériaux métalliques et diélectriques sous forme d’encres imprimables par AJP. Ces différents tests s’appuient sur la réalisation de composants hyperfréquences sur des substrats céramique plats. Le troisième chapitre est consacré à la métallisation sélective par AJP d’objets 3D céramique réalisés par stéréolithographie. Plus particulièrement, ces différents tests aideront à terme à pouvoir métalliser sélectivement des filtres volumiques en céramique fonctionnant aux fréquences millimétriques. Le quatrième chapitre concerne la conception, l’étude et la mise en oeuvre de nouveaux types de composants hybrides et autres interconnexions entièrement imprimables par AJP. L’approche de ce travail est originale par l’utilisation d’une technologie additive innovante de métallisation sélective et son applications sur les composants passifs hyperfréquences
This thesis work is focused on the development of the Aerosol Jet printing (AJP) technology to produce microwave components in the millimeter frequency band and to address 3D component integration issues. The first chapter is devoted to a bibliographic study to compare the different additive technologies available on the market in order to position the AJP in relation to the state of the art. The second chapter is dedicated to the selection and characterization of metallic and dielectric materials that can be printed by AJP. These various tests lead to the production of microwave and millimeter waves components on flat ceramic substrates. The third chapter is devoted to the selective metallization by AJP of 3D ceramic objects produced by stereolithography. More specifically, the various tests will eventually allow ceramic volumetric filters operating at millimeter waves to be selectively metallized. The fourth chapter concerns the design, study and implementation of new types of hybrid components and interconnects that can be fully printed by AJP. This work is original through the use of an innovative additive selective metallization technology applied to microwave and millimeter wave passive components

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Lasota, Marek. "Návrh protetického chodidla s využitím aditivních výrobních technologií." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2018. http://www.nusl.cz/ntk/nusl-382165.

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Subject of this diploma thesis is a design of a prosthetic foot for an additive manufacturing. It is a dynamic foot made of plastic, designed for an 80 kg patient with a second level of a movement aktivity. From a few concepts is chosen one, which is then optimalized and printed with a MJF method. Functional sample is then undergoing static and cyclic tests according to ISO 10328.

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Vocílka, Ondřej. "Využití aditivní technologie pro návrh a výrobu prototypu oční protézy." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-402543.

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This diploma thesis has an aim to fabricate a prototype of esthetical prosthesis using solely Rapid Prototyping aditive technology and to explore the possibility of using commercially available biocompatible materials. In the theoretical part, a description of types of ocular prosthesis types with the focus being on esthetic ocular prosthesis. is given. The practical part of the work offers a comprehensive view on the whole process of the prototype fabrication. It provides a description of creating the 3D model by scanning, geometrical adjustments of the model, textures mapping, print optimization and the printing itself. The closing part of the thesis consists of a discussing focused on an evaluation of the fabricated prototype followed by technical-economical assesment, a proposal of next steps, and a proposal of current usage of the created method.

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Tvrdoň, Radek. "3D tisk kovů robotem." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-443161.

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The diploma thesis presents an overview of additive production technologies and a summary of technologies used for 3D metal printing using a robot. All of them are generally described and at the same time assigned to their specific commercial use, or the academic research that deals with them. The work examines the suitability of the material EN ISO 14341-A: G 3Si1 for 3D printing, for which a modification of the Col Metal Transfer technology, Cycle Step is used. The experimental printout of the sample is evaluated on the basis of surface and mechanical tests. Capillary test, examination of microstructure a macrostructure, tensile test and microhardness test. All of them were satisfactory and the suitability of the welding wire for 3D printing was confirmed by the given technology.

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Unnikrishnan, Divya. "Potentiel de la technologie MID pour les composants passifs et des antennes." Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GRENT009/document.

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La technologie MID (Molded Interconnect Device), fait de leur performance électrique, la flexibilitédans les circuits RF, le potentiel de réduire le nombre de composants, les étapes du processus et laminiaturisation du produit final, a conduit à de nouvelles contraintes à la RF (Radio Frequency) et ledomaine des micro-ondes. Composants moulés sont interconnectées avec des substratsthermoplastiques et les pistes conductrices sont injectés sur la surface. L'objectif de cette thèse estd'étudier la compatibilité de MID pour les applications RF. Les avantages de la technologie MID dansle domaine RF est exploitée pour les lignes de transmission, filtres passifs, coupleurs directionnels etantennes réalisation. La caractérisation RF de différents matériaux de substrat MID et l'étude de laperformance des composants RF ci-dessus sur la base de différentes technologies de fabrication MIDsont inclus dans la thèse. Enfin, le concept d'une étude d'amélioration de la permittivité de certainsthermoplastiques sont également étudiés
MID (Molded Interconnect Devices) technology, owing to their electrical performance,flexibility in RF circuits, its potential to reduce the number of components, process steps andminiaturization of the final product, has led to some new constraints to the RF (RadioFrequency) and microwave domain. Molded components are interconnected withthermoplastic substrates and conductive traces are injected on the surface. The objective ofthis thesis is to study the compatibility of MIDs for RF applications. The advantages of MIDtechnology in the RF domain is exploited for transmission lines, passive filters, directionalcouplers and planar and 3D antennas realization. The RF characterization of various MIDsubstrate materials and the study of the performance of the above RF components based onvarious MID fabrication technologies are included in the thesis. Finally, an permittivityimprovement study of some thermoplastics are also studied

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Filková, Nicole. "Identifikace, analýza a hodnocení rizik spojených s implementací technologie 3D tisku do výrobních procesů." Master's thesis, Vysoké učení technické v Brně. Ústav soudního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-402647.

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The diploma thesis focuses on risk assessment in the area of occupational health and safety, specifically on the risks in the implementation of 3D printing into the production process. The introductory part of the work introduces theoretical background in the area of occupational health and safety, together with the knowledge of 3D printing and methods for identification and risk management. In the following part, the identification, analysis and assessment of risks is carried out on a concrete example. Appropriate measures for their minimization, including financial evaluation, are proposed for the assessed risks.

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Mazoch, Jan. "Topologické optimalizace v technické praxi." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2019. http://www.nusl.cz/ntk/nusl-400688.

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Master’s thesis deals with an issue of 3D printing and of using a topological optimization for editing a shape of a 3D printed product. First part of this thesis provides a general description of a subtractive manufacturing technology, specifically its use in CNC milling machines, and of an additive manufacturing technology which is used in 3D printing. Second part of this thesis describes the topological optimization per se and specific methods which are used in the topological optimization. In the third and the fourth part of this thesis, topological optimization modules of software Ansys and SolidWorks are described. In the fifth part of this thesis, the topological optimization capabilities for 3D printed product on a specific embodiments of a design lightning and a cross-beam are demonstrated.

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Nguyen, Theresa Hoai-Thuong. "ADDITIVE MANUFACTURING FOR ASSISTIVE TECHNOLOGY : Innovative Design for an Ankle Foot Orthosis." Thesis, Jönköping University, JTH, Industridesign, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-51593.

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The following report presents a Master thesis project about a re-design of an ankle foot orthosis using additive manufacturing as the production method, conducted by a student in Spring 2020 as part of the Master’s programme Industrial Design at Jönköping University’s School of Engineering. Ankle foot orthoses are the most prescribed lower extremity orthoses worldwide and are worn in a visually obtrusive way making patients feel stigmatized for their disability. The social stigma makes it emotionally difficult for many users to wear an AFO frequently enough for proper rehabilitation. Despite its significance and wide spread use, its design has not changed for over 50 years. Traditional manufacturing methods are difficult to work with and make customization options very limited. By using digital additive manufacturing methods like 3D Scanning, 3D printing and computer simulations, it is possible to offer personalized looks for AFOs by implementing almost any custom pattern expressed in cut-outs on the AFO surface. That kind of perforation simultaneously solves the problem of bad perspiration and air flow. The freedom of graphical expression in those patterns invite the patient to participate in the design process themselves to create an ankle foot orthosis that is their own. That revolutionary twist on the manufacturing and design process empowers the user to take control over their disability to the furthest degree possible and returns the human right of self-determination and independence to them.
Följande rapport presenterar ett examensarbete gällade en omdesign av en ankel-fot-ortos med additiv tillverkning som produktionsmetod, genomförd av en student våren 2020 som del av masterprogrammet Industrial Design vid Jönköpings universitets tekniska högskola. Ortoser för fotleden är de mest föreskrivna ortoserna för underkroppen i hela världen och bärs på ett visuellt påträngande sätt vilket gör att patienterna kan känna sig annorlunda eller utanför för sin funktionsnedsättning. Den sociala stigmatiseringen gör det känslomässigt svårt för många användare att bära en AFO ofta nog för korrekt rehabilitering. Trots dess betydelse och breda användning har designen inte förändrats på över 50 år. Traditionella tillverkningsmetoder är svåra att arbeta med och begränsar alternativen för anpassning. Genom att använda digitala metoder för additiv tillverkning som 3D-skanning, 3D-utskrift och datorsimuleringar är det möjligt att erbjuda ett personligt utseende för AFO genom att införa en stor mängd anpassade mönster i form av utskärningar på AFO-ytan. Denna typ av perforering löser samtidigt problemet med svett och dåligt luftflöde. Friheten för grafiskt uttryck genom dessa mönster låter patienten delta i själva designprocessen för att fotledsortosen ska kännas som deras egen. Detta nya synsätt på utveckling på tillverknings- och designprocessen gör det möjligt för användaren att ta kontroll över sin funktionsnedsättning i största möjliga grad och återställer känslan av självständighet.

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Valtrová, Martina. "Píst zážehového motoru vyráběný aditivní technologií." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-449789.

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The first objective of this thesis was compiling research about currently produced pistons for internal combustion engines and about additive manufacturing and based on the acquired information deciding which type of piston makes the most of the advantages. Following this research, the next step was creating a design adjustment of a piston, which was previously designed with the conventional methods of manufacturing in mind, in a way that would make the best use of the different possibilities of additive manufacturing. There was also an optimisation carried out, which depicted the densities of material elements in the piston, showing where the material was less important. There were three variants of the additive manufactured piston created, ranging from a relatively conservative design, which could be theoretically produced by conventional methods with a more substantial subtraction of material added, to a design which could only be produced via additive manufacturing. A thermo-structural analysis at maximum engine load was carried out for all these piston models. Based on these data, a conclusion was made, whether the use of additive manufacturing was justified over the use of the conventional subtractive methods.

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Joshi, Chetan. "Contrôle du diagramme de rayonnement d'une antenne en technologie imprimée à l'aide d'un superstrat diélectrique inspiré de la transformation d'espace." Thesis, Paris, ENST, 2016. http://www.theses.fr/2016ENST0079/document.

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La Transformation d’Espace appelée aussi Transformation Optique (TO) est un outil de conception électromagnétique puissant qui a permis la conception de nouveaux dispositifs tels que la célèbre “cape d'invisibilité”. Cette thèse s’inscrit dans la continuité directe de celle de M.D. Clemente Arenas (Application de la transformation d'espace à la conception d'antennes à diagramme de rayonnement contrôlé, 2014) et porte sur l’utilisation de la TO pour modifier drastiquement le rayonnement d’une antenne patch. Ces fortes modifications du rayonnement sont habituellement obtenues avec l’aide d’un superstrat encombrant et constitué de matériaux ayant une perméabilité et permittivité exotiques (métamatériaux). L’objectif est donc ici de réduire cet encombrement et de simplifier la réalisation en utilisant des matériaux diélectriques standards. Ainsi, grâce au superstrat développé, une antenne patch ayant un gain réalisé de 7 dB devient une antenne présentant deux lobes dans le plan azimutal de gain réalisé de 3.5 dB. Le superstrat, d’épaisseur 0.12λ, est conçu à l’aide de deux matériaux uniquement : Alumine (εr = 9.9) et Fullcure (εr = 2.8), alors que le profil initial comporte une permittivité variant entre 1 et 15 et une perméabilité entre 0.3 et 3. Divers degrés de libertés dans la conception permettent d'adapter notre solution pour concevoir d’autres superstrats avec des fonctionnalités différentes: diagramme ayant une ouverture de plus de 180° dans un plan, diagramme end-fire, etc. Les applications visées sont notamment celles de l’aéronautique pour lesquelles il existe aujourd’hui sur les aéronefs plusieurs dizaines d’antennes pour assurer toutes les liaisons nécessaires aux communications, à l’identification, au positionnement, etc. La géométrie du porteur conduit alors à utiliser plusieurs antennes protubérantes pour remplir cette mission. Cependant pour un avion, ces excroissances contribuent à dégrader l’aérodynamisme de l’appareil ce qui se traduit par une consommation plus importante. Le but est donc de proposer des solutions antennaires à rayonnement nonconventionnel et non protubérante compatible avec une intégration sur dérive ou fuselage. Le concept est validé à l'aide d'une maquette réalisée avec une imprimante 3D et avec le soutien d’Airbus Group Innovations
Transformation Optics (TO) is a powerful electromagnetic design tool that enables the design of new devices such as the famous "invisibility cloak". This thesis is in direct continuation of that of M.D. Clemente Arenas (Application de la transformation d'espace à la conception d'antennes à diagramme de rayonnement contrôlé, 2014) and focuses on the use of the TO to drastically change radiation of a patch antenna. These sharp changes in radiation pattern are usually obtained using bulky superstrates made of metamaterials having exotic permeability and permittivity values. The objective of this thesis is to reduce the thickness of the superstrate and simplify the fabrication by enabling the use of standard dielectric materials. Thus, a patch antenna with realized gain of 7 dB is transformed, with the help of proposed superstrate, into an antenna having two lobes in the azimuth plane withrealized gain of 3.5 dB. The 0.12λ thick superstrate is designed using two standard dielectric materials only: Alumina (εr = 9.9) and FullCure (εr = 2.8), whereas the previous solution had variation in permittivity between 1 and 15 and in permeability between 0.3 and 3. Various degrees of freedom in the design allow adapting this solution to develop new superstrates for other applications: radiation pattern with HPBW greater than 180 ° in one plane, end-fire radiation pattern, etc. Target applications include those of aeronautics. Today, dozens of antennas on an aircraft are required to ensure the necessary communications links, identification, positioning and other purposes. The structure of the aircraft necessitates use multiple antennas to fulfill this mission, which are fixed and protrude on fuselage or wings. However, for an aircraft, these protuberances contribute to the aerodynamic drag, which results in higher fuel consumption. Therefore, the objective is to propose conformal antenna solutions with unconventional radiation pattern, which can be eventually integrated on fuselage or rudder. The concept is validated using a model made with a 3D printer and with the support of Airbus Group Innovations

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Malé, Alemany Marta. "El potencial de la fabricación aditiva en la arquitectura : hacia un nuevo paradigma para el diseño y la construcción." Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/387812.

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Como lo hicieron el PC e Internet en materia de información y comunicación, la Fabricación Aditiva (FA) está revolucionando los procesos de diseño y fabricación, abriendo un nuevo paradigma de producción que genera cambios e innovaciones relevantes en muchos ámbitos. Su impacto actual en otros sectores sugiere que la FA tiene igual potencial para transformar los procesos productivos de la arquitectura y de la construcción. Por ello, la autora se pregunta qué tipo de cambios puede generar y si ello supondrá un cambio de paradigma productivo igualmente disruptivo en estos dos campos. Para responder a ambas cuestiones, la presente tesis ofrece una valoración crítica del potencial de la FA aplicada a la arquitectura, analizando su impacto sobre los procesos de diseño y construcción. La primera parte incluye un estudio transversal de varios sectores de actividad, que permite constatar cómo esta tecnología está generando transformaciones radicales, con implicaciones globales de carácter social, económico y ambiental. En la segunda parte, se analiza la adaptación de la FA a los condicionantes propios de la arquitectura. Para ello, se presentan las iniciativas pioneras en su aplicación a gran escala y los proyectos dirigidos por la autora en el marco académico, que investigan qué procesos son necesarios para implementar esta tecnología desde y hacia el proyecto arquitectónico. Estos trabajos de investigación y experimentación multidisciplinar combinan la búsqueda de nuevos materiales, la creación de herramientas a medida y la programación de códigos de diseño específicos. Por último, se ofrece una síntesis de los resultados que sirve de base para valorar los avances recientes en la aplicación de la FA en la arquitectura, a escala mundial. En conjunto, la tesis demuestra que la investigación en este campo está en plena ebullición y que las aplicaciones de la FA van a generar cambios muy importantes, que suponen el inicio de un nuevo paradigma para el diseño arquitectónico y la construcción.
As did the PC and the Internet for the information and communication realms, Additive Manufacturing (FA) is revolutionizing the design and manufacturing processes, opening up a new production paradigm that generates significant changes and innovations in many areas. Its current impact on other sectors suggests that AM has the same potential to transform the production processes of architecture and construction. The author thus wonders what kind of changes can it generate and whether they will imply a productive paradigm shift that is equally disruptive in these two fields. To answer both questions, this thesis offers a critical assessment of the potential of AM applied to architecture, analyzing its impact on the design and construction processes. The first part includes a cross-sectional study of several activity sectors, which allows seeing how this technology is generating radical transformations, with social, economic and environmental implications at a global scale. The second part analyses the adaptation of AM to the specific conditions of architecture. The thesis presents the pioneering initiatives of its application at largescale, and the projects directed by the author in the academic context, which investigate what processes are necessary to implement this technology to and from the architectural project. These experimental and multidisciplinary works combine the research of new materials, the creation of custom devices and the programming of specific design codes. The synthesis of the results is later used as a reference to identify and assess the current progress in implementing AM technologies in architecture, worldwide. Altogether, the thesis demonstrates that research in this field is currently in full swing. Moreover, the most recent applications also indicate that AM is on track to generate significant changes, which represents the beginning of a new paradigm for architectural design and construction.

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Nioti, Antonia Evgenia. "Additive Manufacturing in Orthopedics and Craniomaxillofacial Surgery for the Development of High-risk Custom-made Implants : A Qualitative Study of Implementation Factors from a Multi-stakeholder Perspective." Thesis, Uppsala universitet, Industriell teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-424980.

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Additive manufacturing (AM) has enabled the possibility for the hospitals to become their own implant producers developing implants that are tailored to patient’s anatomy. Despite the enormous potential of custom-made implants there are challenges that complicate the implementation of them into clinical practice. The aim of this research is to (1) identify the main driving forces and barriers for the delivery of custom-made implants; (2) explore staff stakeholder views and practices related to the implementation of AM in surgery for the development of custom-made implants; (3) formulate recommendations on how to cope with the implementation challenges. The research method was an explorative qualitative study consisted of a literature review on the challenges of custom-made implants in clinical applications coupled with the collection and inductive analysis of empirical data. The empirical study was based on ten semi-structured interviews conducted among both domestic and international hospital managers medical doctors and research engineers. The consolidated framework for implementation research (CFIR) was utilized for data collection. Using the five domains of CFIR, the following results were obtained: (1) Characteristics of individuals: Most research participants indicated a positive attitude towards the innovation expressing self-efficacy to its use; (2) Intervention characteristics: Custom-made implants were perceived to have a relative advantage in surgical practice due to their high degree of observability and geometrical adaptability providing increased surgical quality, perfect patient fit and better understanding of pathologies. However, high implementation costs, low degree of trialability and high degree of complexity in the development process were regarded as drawbacks of the innovation; (3) Outer setting: the regulatory uncertainty and lack of reimbursement limit the accessibility of custom-made implants to low income populations; (4) Inner setting: scarcity of resources, staff resistance to change, insufficient management support, communication difficulties, limited access to educational materials and training opportunities as well as lack of time and innovative capacity were regarded by the majority of participants as implementation barriers; (5) Process: central for the success of implementation is the need for a coherent implementation plan and evaluation process as well as the engagement of key stakeholders such as hospital managers, payers, regulatory and implementation advisors. This dissertation proffers a deeper understanding of the implementation issues related to custom-made implants and offers preliminary recommendations on how to cope with implementation impediments through the use of Rogers diffusion of innovation coupled with concepts from the field of organizational change and innovation management including Clayton’s disruptive innovation.

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Chevlen, Abraham Moses Chevlen. "New Technology’s Potential Future and Government Policy Direction: The Case of China’s 3D Printing Construction Technology and Its Possible Effects on China’s Housing Bubble." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1525691636175256.

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Maric, Josip. "Sustainability and responsibility in the digitalization era : a study of consumer-level 3D printing technology." Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTD015.

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Dans cette thèse, nous étudions les concepts de durabilité et de responsabilité à l’ère de la numérisation, époque marquée par l’émergence de nouvelles technologies numériques de rupture. Nous cherchons à identifier dans quelle mesure les technologies numériques peuvent contribuer aux objectifs de durabilité et de responsabilité et comment une technologie numérique spécifique peut faciliter l’atteinte de ces objectifs.Ces critères nous ont conduits au choix de la fabrication additive, plus communément connue sous le nom de « technologie d'impression 3D » (3DP). Observée à travers du prisme conceptuel de l'innovation responsable, notre étude dévoile au travers de ses principaux résultats certains des mystères que revêtent les 3DP auprès du grand public. En combinant le concept d'innovation responsable avec une technologie numérique spécifique, nous avons adopté une approche de recherche utilisant la théorie enracinée pour suivre les processus d'adoption/diffusion actuels à partir du terrain, et identifier les utilisateurs précurseurs et influents du domaine des 3DP. Ainsi, les principaux résultats peuvent être divisés en deux thèmes, dans un premier temps pour expliquer les caractéristiques des systèmes sociotechniques dans lequel la 3DP est située et, dans un deuxième temps, discuter des avantages et des défis sociaux, économiques et environnementaux de 3DP pour le grand public. Dans la seconde partie, la première section, consacrée aux caractéristiques du système sociotechnique, se concentre sur le processus d'adoption actuel, l'identification des utilisateurs influents prenant forme dans la culture ‘Maker’ et dans les espaces de coworking. Cette section présente également les caractéristiques actuelles de ces primo utilisateurs et les particularités de 3DP pour le grand public, telles que le déséquilibre hommes-femmes pour les utilisateurs actuels, et la manière dont contribueront la 3DP au développement de nouveaux produits. La seconde section de nos principaux résultats offre une analyse détaillée des avantages et des défis sociaux, économiques et environnementaux spécifiques de 3DP au niveau consommateur.Ces résultats indiquent qu'il existe une attente sociétale croissante auprès des 3DP pour adoucir les systèmes de production actuels et aboutir à des logiques de production plus durables. Par conséquent, les opportunités économiques offrent la possibilité de développer de nouveaux services et produits dans le marché des 3DP, caractérisé par une forte expansion et de faibles barrières à l'entrée, qui séduisent une grande variété de petites et moyennes entreprises (PME). Enfin, la nature environnementale des 3DP au niveau consommateur, même si elle offre des possibilités prometteuses pour préserver les ressources, optimiser la production, maîtriser l’obsolescence planifiée et recycler et réutiliser les matériaux, fait toujours face à un certain nombre de problèmes, qui limitent les apports environnementaux dans le cas d’une adoption de masse. Les contributions théoriques correspondent principalement aux spécificités du processus d'adoption des 3DP au niveau consommateur, à l’identification des caractéristiques des primo utilisateurs et des utilisateurs influents, mais aussi aux implications en termes de développement durable, sujets rarement traités dans la littérature en gestion. Nos principales conclusions apportent également des informations détaillées aux praticiens qui peuvent mener leurs activités entrepreneuriales, en mobilisant ces technologies pour améliorer les modèles d’affaires existants ou en développant des produits et services entièrement nouveaux. Les législateurs peuvent tirer parti des informations sur les pratiques 3DP actuelles et élaborer des politiques pour soutenir la recherche et l'innovation dans le domaine des 3DP ou pour identifier les menaces potentielles pour le public, telles que les risques liés à la propriété intellectuelle ou les problématiques de standard
This study investigates the concepts of sustainability and responsibility in innovation through the processes of digitalization, marked by the emergence of new disruptive digital technologies. We observe the link between the digitalization and sustainability to understand how a specific digital technology can lead to sustainable and responsible outcomes. These criteria led us to additive manufacturing, or more commonly known, 3D Printing (3DP) technology.We adopted a responsible innovation concept as a set of principles to guide our study on 3DP. Moreover, this study design enabled us to align responsible innovation with existing research methods such as grounded theory. Through a bottom-up research approach, we observed trajectories of the current 3DP adoption/diffusion process and identified early users within their sociotechnical environment where 3DP is currently available. This constituted a solid ground to discuss 3DP sustainable and responsible nature and related implications. Responsible innovation concept, 3DP technology and our research methods are described in the Part I of this document.Part II elaborates main findings that can be divided into two sections. In the first section, we present characteristics of the sociotechnical system, current adoption process, 3DP innovation characteristics, and identify lead users. Current lead users of consumer-level 3DP are seen in the form of Maker culture and the coworking spaces. We present the insights on this specific interaction between the 3DP and Maker culture, whilst also discussing characteristic gender imbalance and new product development.The second section offers detailed analysis of consumer-level 3DP social, economic and environmental implications. Social implications indicate that there is an increasing societal expectation where 3DP is expected to lead a transformation towards more sustainable means of production. Economic implications are concentrated on the business opportunities relying on the growing 3DP market. As an evolving and niche market, current expansion and low-entry barriers are attracting interest of Small and Medium Entrepreneurs (SMEs) who develop new 3DP services and products. Lastly, even though with a promising potential to preserve raw resources, optimize production, tackle planned obsolescence, ensure recycling and reuse of materials, consumer-level 3DP still faces several environmental challenges. Possible rebound effect in energy and resources could lead to consequences that undermine its additive nature, where ecology is not a central topic for 3DP further development.Theoretical contributions of our study can be summarized in the specificities of consumer-level 3DP adoption process, characteristics of the early adopters and sustainability implications. These topics are scarcely covered in management research. Moreover, our key findings also provide detailed managerial contributions for the practitioners and the policy-makers. These can contribute to entrepreneurial activities that demand 3DP alignment with existing business models or development of new products and services based on this technology. Policy-makers can obtain insights on the current 3DP practices that can help guide policies to support research and innovation linked to 3DP technology. Our study insights can assist their understanding of possible threats hidden in Intellectual Property (IP), security and standardization issues related to 3DP technology.Finally, our main intention was to contribute to the ongoing scholar debate about the 3DP technology, digitalization and sustainability. For these purposes, we have developed a detailed thesis monograph offering a broad range of findings, whilst two fully published peer-reviewed publications, alongside several conference papers, ensure public visibility of our work. The published peer-reviewed articles are available in the Appendices section of this document

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Lacombe, Elsa. "Évaluation de la technologie photonique sur silicium pour le développement de liens sans fil innovants visant 40 Gb/s au-delà de 200 GHz." Thesis, Université Côte d'Azur (ComUE), 2018. http://www.theses.fr/2018AZUR4095/document.

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Avec l’explosion du trafic de données mobiles, des débits supérieurs au Gb/s deviennent nécessaires pour l’utilisateur. Ainsi, le réseau de communication est en cour d’amélioration afin de promouvoir le déploiement de la 5G, notamment grâce au développement et à l’installation de systèmes sans fil d’onde millimétrique (mmW) à 10 Gb/s. Néanmoins, pour délivrer de tels débits, les liens fronthaul/backhaul sans fil connectés au cœur de réseau devront supporter des flux de données supérieurs à 40 Gb/s. Cet enjeu suscite un intérêt croissant pour les fréquences sub-mmW et THz (0.1 THz – 1 THz) autour desquelles des bandes passantes (BPs) de 100 GHz sont accessibles. Il serait en effet possible d’atteindre un débit de 100 Gb/s, tout en utilisant des formats de modulation simples et ainsi réduire la consommation d’énergie du système. Visant le marché de masse des applications haut-débits, la technologie Photonique sur Silicium est particulièrement attractive pour générer des BPs naturellement larges et pour sa capacité à forts niveaux d’intégration et faible cout de fabrication. Dans cette thèse, une technologie Photonique sur Silicium industrielle a donc été évaluée durant le développement d’un émetteur intégré THz fonctionnant sur la base d’une photodiode et pouvant délivrer 100 Gb/s. Le développement d’une antenne THz faible cout et compacte est également un aspect majeur de cette thèse afin de permettre la transmission point-à-point du signal THz. En effet, une antenne intégrée sur substrat organique faible cout et à faibles pertes et une lentille fabriquée par impression 3D ont été développées afin d’évaluer ces technologies de prototypage industriel au-delà de 200 GHz
With the booming of mobile data traffic, the need for higher data-rates is clearly felt. To cope with this strong demand and support the 5G roll-out, the capacity of the mobile communication network is being improved every day with many solutions, among which the development and installation of millimeterwave (mmW) wireless systems operating at up to 10 Gb/s. However, in order to deliver such high speeds to the user, the fronthaul/backhaul network sending data back to the core network would require above 40 Gb/s data-rate wireless links. This challenge generates a growing interest for sub-mmW and THz frequencies (0.1 THz – 1 THz) at which up-to 100 GHz bandwidth (BW) is accessible. In such BW, it would be possible to achieve up to 100 Gb/s data-rates while using simple modulation schemes to reduce the wireless system’s power consumption. Targeting mass-market high data-rates applications, Silicon Photonics technology seems very promising as it benefits from wide intrinsic BW and powerefficient components, as well as high integration levels and low manufacturing costs. In this context, a main aspect of this PhD project is the evaluation of an industrial Silicon Photonics technology for the development of a THz system-on-chip transmitter capable of reaching up to 100 Gb/s using a photodiode. Since THz antennas are also a hot topic for THz point-to-point transmission, a second aspect of this PhD study is the design of a low-cost and compact THz antenna-system. Hence, a planar antenna using low-loss organic packaging technology and a 3D-printed plastic lens were developed in order to assess those industrial prototyping techniques above 200 GHz

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Vašek, Vojtěch. "Použití modelů zhotovených technologii 3D tisku při výrobě odlitků do bentonitových forem na formovací lince." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-319282.

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Shortening of the time required to make first product after demand is a crucial factor in every field of industry, not excluding the foundry. To lower this delay, there are rapid prototyping methods. The aim of this thesis is to execute an experiment and then evaluate possibilities of using patterns made by 3D FDM printer on an automatic molding line.

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Guráň, Radoslav. "Konstrukce nanášecího systému pro zpracování dvou kovových prášků pomocí 3D tisku." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-399327.

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The thesis deals with the design, construction and testing of two different metal powder coating equipment, which is able to work with SLM 280HL metal 3D printer. Since the field of multimaterial metal printing by selective laser melting (SLM) has not been significantly investigated yet, an overview of existing patents and possible approaches to the solution has been developed. The device has been successfully designed and a series of tests was carried out defining the issue of applying an improved head that uses a nozzle and an eccentric vibration motor. Based on the experiments performed, the coating parameters of the multimaterial layer of FeAm and 316L materials were defined. A control system for the partial process automation was created for the proposed device. The device was implemented in a printer that demonstrated both the ability to apply a single multimaterial layer of at least 50 m thickness, and the ability to produce a 3D multimaterial component comprised of up to 200 layers and containing material change across all axes.

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Fenollosa, Artés Felip. "Contribució a l'estudi de la impressió 3D per a la fabricació de models per facilitar l'assaig d'operacions quirúrgiques de tumors." Doctoral thesis, Universitat Politècnica de Catalunya, 2019. http://hdl.handle.net/10803/667421.

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La present tesi doctoral s’ha centrat en el repte d’aconseguir, mitjançant Fabricació Additiva (FA), models per a assaig quirúrgic, sota la premissa que els equips per fer-los haurien de ser accessibles a l’àmbit hospitalari. L’objectiu és facilitar l’extensió de l’ús dels prototips com a eina de preparació d’operacions quirúrgiques, transformant la pràctica mèdica actual de la mateixa manera que en el seu moment ho van fer tecnologies com les que van facilitar l’ús de radiografies. El motiu d’utilitzar FA, en lloc de tecnologies més tradicionals, és la seva capacitat de materialitzar de forma directa les dades digitals obtingudes de l’anatomia del pacient mitjançant sistemes d’escanejat tridimensional, fent possible l’obtenció de models personalitzats. Els resultats es centren en la generació de nou coneixement sobre com aconseguir equipaments d’impressió 3D multimaterials accessibles que permetin l’obtenció de models mimètics respecte als teixits vius. Per facilitar aquesta buscada extensió de la tecnologia, s’ha focalitzat en les tecnologies de codi obert com la Fabricació per Filament Fos (FFF) i similars basades en líquids catalitzables. La recerca s’alinea dins l’activitat de desenvolupament de la FA al CIM UPC, i en aquest àmbit concret amb la col·laboració amb l’Hospital Sant Joan de Déu de Barcelona (HSJD). El primer bloc de la tesi inclou la descripció de l’estat de l’art, detallant les tecnologies existents i la seva aplicació a l’entorn mèdic. S’han establert per primer cop unes bases de caracterització dels teixits vius -sobretot tous- per donar suport a la selecció de materials que els puguin mimetitzar en un procés de FA, a efectes de millorar l’experiència d’assaig dels cirurgians. El caràcter rígid dels materials majoritàriament usats en impressió 3D els fa poc útils per simular tumors i altres referències anatòmiques. De forma successiva, es tracten paràmetres com la densitat, la viscoelasticitat, la caracterització dels materials tous a la indústria, l’estudi del mòdul elàstic de teixits tous i vasos, la duresa d’aquests, i requeriments com l’esterilització dels models. El segon bloc comença explorant la impressió 3D mitjançant FFF. Es classifiquen les variants del procés des del punt de vista de la multimaterialitat, essencial per fer models d’assaig quirúrgic, diferenciant entre solucions multibroquet i de barreja al capçal. S’ha inclòs l’estudi de materials (filaments i líquids) que serien més útils per mimetitzar teixits tous. Es constata com en els líquids, en comparació amb els filaments, la complexitat del treball en processos de FA és més elevada, i es determinen formes d’imprimir materials molt tous. Per acabar, s’exposen sis casos reals de col·laboració amb l’HJSD, una selecció d’aquells en els que el doctorand ha intervingut en els darrers anys. L’origen es troba en la dificultat de l’abordatge d’operacions de resecció de tumors infantils com el neuroblastoma, i a la iniciativa del Dr. Lucas Krauel. Finalment, el Bloc 3 té per objecte explorar nombrosos conceptes (fins a 8), activitat completada al llarg dels darrers cinc anys amb el suport dels mitjans del CIM UPC i de l’activitat associada a treballs finals d’estudis d’estudiants de la UPC, arribant-se a materialitzar equipaments experimentals per validar-los. La recerca ampla i sistemàtica al respecte fa que s’estigui més a prop de disposar d’una solució d’impressió 3D multimaterial de sobretaula. Es determina que la millor via de progrés és la de disposar d’una pluralitat de capçals independents a fi de capacitar la impressora 3D per integrar diversos conceptes estudiats, materialitzant-se una possible solució. Cloent la tesi, es planteja com seria un equipament d’impressió 3D per a models d’assaig quirúrgic, a fi de servir de base per a futurs desenvolupaments.
La presente tesis doctoral se ha centrado en el reto de conseguir, mediante Fabricación Aditiva (FA), modelos para ensayo quirúrgico, bajo la premisa que los equipos para obtenerlos tendrían que ser accesibles al ámbito hospitalario. El objetivo es facilitar la extensión del uso de modelos como herramienta de preparación de operaciones quirúrgicas, transformando la práctica médica actual de la misma manera que, en su momento, lo hicieron tecnologías como las que facilitaron el uso de radiografías. El motivo de utilizar FA, en lugar de tecnologías más tradicionales, es su capacidad de materializar de forma directa los datos digitales obtenidos de la anatomía del paciente mediante sistemas de escaneado tridimensional, haciendo posible la obtención de modelos personalizados. Los resultados se centran en la generación de nuevo conocimiento para conseguir equipamientos de impresión 3D multimateriales accesibles que permitan la obtención de modelos miméticos respecto a los tejidos vivos. Para facilitar la buscada extensión de la tecnología, se ha focalizado en las tecnologías de código abierto como la Fabricación por Hilo Fundido (FFF) y similares basadas en líquidos catalizables. Esta investigación se alinea dentro de la actividad de desarrollo de la FA en el CIM UPC, y en este ámbito concreto con la colaboración con el Hospital Sant Joan de Déu de Barcelona (HSJD). El primer bloque de la tesis incluye la descripción del estado del arte, detallando las tecnologías existentes y su aplicación al entorno médico. Se han establecido por primera vez unas bases de caracterización de los tejidos vivos – principalmente blandos – para dar apoyo a la selección de materiales que los puedan mimetizar en un proceso de FA, a efectos de mejorar la experiencia de ensayo de los cirujanos. El carácter rígido de los materiales mayoritariamente usados en impresión 3D los hace poco útiles para simular tumores y otras referencias anatómicas. De forma sucesiva, se tratan parámetros como la densidad, la viscoelasticidad, la caracterización de materiales blandos en la industria, el estudio del módulo elástico de tejidos blandos y vasos, la dureza de los mismos, y requerimientos como la esterilización de los modelos. El segundo bloque empieza explorando la impresión 3D mediante FFF. Se clasifican las variantes del proceso desde el punto de vista de la multimaterialidad, esencial para hacer modelos de ensayo quirúrgico, diferenciando entre soluciones multiboquilla y de mezcla en el cabezal. Se ha incluido el estudio de materiales (filamentos y líquidos) que serían más útiles para mimetizar tejidos blandos. Se constata como en los líquidos, en comparación con los filamentos, la complejidad del trabajo en procesos de FA es más elevada, y se determinan formas de imprimir materiales muy blandos. Para acabar, se exponen seis casos reales de colaboración con el HJSD, una selección de aquellos en los que el doctorando ha intervenido en los últimos años. El origen se encuentra en la dificultad del abordaje de operaciones de resección de tumores infantiles como el neuroblastoma, y en la iniciativa del Dr. Lucas Krauel. Finalmente, el Bloque 3 desarrolla numerosos conceptos (hasta 8), actividad completada a lo largo de los últimos cinco años con el apoyo de los medios del CIM UPC y de la actividad asociada a trabajos finales de estudios de estudiantes de la UPC, llegándose a materializar equipamientos experimentales para validarlos. La investigación amplia y sistemática al respecto hace que se esté más cerca de disponer de una solución de impresión 3D multimaterial de sobremesa. Se determina que la mejor vía de progreso es la de disponer de una pluralidad de cabezales independientes, a fin de capacitar la impresora 3D para integrar diversos conceptos estudiados, materializándose una posible solución. Para cerrar la tesis, se plantea cómo sería un equipamiento de impresión 3D para modelos de ensayo quirúrgico, a fin de servir de base para futuros desarrollos.

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Cosker, Mathieu. "Conception d'antennes à base de métal liquide pour applications multiples." Thesis, Université Côte d'Azur (ComUE), 2017. http://www.theses.fr/2017AZUR4145/document.

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Aujourd’hui l’électronique fait partie intégrante de nos vies. En effet, de plus en plus d’objets intègrent de l’électronique permettant de les connecter, on appelle cela l’internet des objets (IoT). Tous ces dispositifs disposent d’une connectivité sans fil, rendant ainsi indispensable l’intégration d’une ou plusieurs antennes. De plus, l’électronique devant s’adapter à des objets de plus en plus petits et flexibles embarquant de plus en plus de capteurs tout en consommant de moins en moins d’énergie, il est intéressant de se pencher sur l’étude de nouveaux matériaux pour la réalisation d’antennes devant s’adapter à ces nouvelles contraintes. Dans ce cadre, nous nous sommes attachés dans ce travail de recherche, à la conception de structures antennaires à base de métaux liquides à température ambiante dans le but de réaliser des antennes conformables de formes complexes associant l’impression 3D, des antennes reconfigurables et des structures rayonnantes ayant la capacité de capteur. Dans ce manuscrit des prototypes d’antenne comportant ces caractéristiques ont été simulés, réalisés et mesurés
Today, electronic is an integral part of our lives. Indeed, more and more objects integrate electronics to connect each other, this is the Internet of Things (IoT). All of these wireless devices need one or more antennas. Furthermore, It’s useful to develop new materials to realize new antennas that fit with new constraints: smaller and flexible objects, more and more sensors and less and less consuming.In this context, we have focused this research on antenna structures based on metals which are liquid at room temperature to realize conformable antennas of complex shapes combining 3D printing, reconfigurable antennas and radiant structures with the ability to sensor. In this manuscript, antenna prototypes with these characteristics have been simulated, realized and measured

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Resler, Tomáš. "Návrh domácí brány pro zařízení IoT využívající technologii Z-Wave." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2019. http://www.nusl.cz/ntk/nusl-400940.

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This dissertation deals with the platform Z-Wave. This platform tries to create an universal system for smart home. The theoretical part of the work describes in details the platform itself as well as the applicable libraries for programming of applications and the available equipments. The practical part presents the new custom gateway. The hardware of this gateway is designed with utilization of the Z-Wave module, Raspberry Pi 3 microcomputer, touchscreen, powerbank and the body of the system. The body has been designed in the Solid Works CAD system and printed on a 3D printer. The needed firmware was loaded into the Z-Wave module ZM5304 and this module has been interconnected with the Raspberry Pi 3 through the printed circuit board of the custom design. The gateway drives OpenZWave network through the new own application written with help of Python wrapper of the library OpenZWave and other open source components. The part of the work is also the list and description of the alternative commercial gateways available on the Czech market.

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Jemai, Norchene. "Développement de la technique de sérigraphie pour la formation de billes de connexions inférieures a 100µm pour l'assemblage 3D : optimisation et étude de fiabilité." Thesis, Toulouse, INSA, 2010. http://www.theses.fr/2010ISAT0010/document.

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L’assemblage et le conditionnement en électronique représentent un enjeu de création de nouveaux systèmes électroniques hybrides rassemblant sur un même substrat des éléments électroniques, optiques, mécaniques… La technologie Flip-chip , introduite par IBM et baptisée C4 (Control Collapse Chip Connection), garantit une plus grande densité d’intégration tout en gardant les mêmes dimensions de puce. Au coeur de cette technologie, le « Bumping » est un procédé qui consiste en l’introduction d’une microbille conductrice entre deux plots de connexion des puces afin de réaliser une liaison électrique et mécanique avec le niveau de packaging suivant. La technique de dépôt par sérigraphie de pâte à braser est récemment devenue pratique en raison de son adaptation aux alliages sans plomb. Cette méthode présente l'avantage d'un faible coût et d'une possible production à grande échelle. Nous avons donc choisi de développer cette technique afin d’obtenir des matrices de connexions électriques de dimensions comprises entre 50 μm et 100 μm, pour une pâte à braser de type Sn3.0Ag0.5Cu. Nous avons déterminé les paramètres de sérigraphie afin d’obtenir un minimum d’étalement de pâte pour un remplissage maximum des ouvertures du masque choisi en Ni-électroformé d’épaisseur 50μm : une vitesse de racle de 20mm/s et une vitesse de démoulage de 4mm/s sont par exemple à retenir pour une pâte de type 5. L’étude du masque de sérigraphie a conduit au choix d’ouvertures circulaires. Des formes de billes circulaires ont été obtenues pour des UBM (Under Bump Metallurgy) également circulaires, de diamètre ¼ et ½ le diamètre de l’ouverture du masque. L’optimisation du profil de refusion a permis de déterminer qu’un palier à 180°C, un TAL de 90s ou plus et une température maximale à 250°C favorisaient l’obtention de billes circulaires avec absence de vides. Pour une pâte de type 6, des billes de 60à 70μm de diamètre ont été obtenues pour des ouvertures de masque de 100μm. Une étude de fiabilité de ces billes à partir de tests de cisaillement et de l’analyse des IMC (composés intermétalliques) formés après refusion a permis de montrer que des UBM en Cr-Cu-Au, de diamètre égal à la moitié de l’ouverture du masque, permettaient d’assurer un meilleur maintien mécanique des billes
The semiconductor industry has continuously improved its products by increasing the density of integration resulting in an increasing of the I/Os, always with a low cost requirement. To obtain high-density and high-speed packaging, the Flip-Chip interconnection technology was introduced by IBM also called C4 (Control Collapse Chip Connection). Solder bumps have been widely used in electronic industry and were generally based on the Sn-Pb alloy, for its low melting point and good wetting property. Containing highly toxic element (Pb), Pb-Sn solder alloy has been banned. The ternary alloy Sn-Ag-Cu seems to be the best compromise, in fact it as physical and chemical characteristics equivalent to that of Sn-Pb.In this study we are interested to optimize stencil printing process and adjust it with the flip-chip technology, in order to obtain solder bumps which height is between 50µm and 100µm associated to pitches less than or equal to 200µm, using Sn-3.0Ag-0.5Cu solder paste. We have optimized the stencil printing parameters machine, the stencil apertures shape and size (circular shape and 50µm height, for a Ni-electroformed stencil). Spherical solder balls have been achieved with circular UBM (Under Bump Metallurgy), which diameter is ¼ and ½ the diameter of the stencil aperture. The reflow thermal profile is the key to the formation of a reliable solder bump. It must allow a homogeneous reflow for all particles of the metallic solder paste. We define a thermal profile with a Time above liquidus (TAL) of 90s, a temperature in soaking zone (Ts) of 180°C and a maximum temperature (Tmax) of 250°C. For type 6 solder pastes, balls of 60-70µm diameter have been obtained for 100µm stencil apertures.The quality of a solder joint is directly related to the adhesion of the solder ball to the substrate. Among the various methods of mechanical testing, shear testing is the most widely used to assess the strength of the attachment of beads to the substrate and determine the fragility of the ball at the interface caused by the intermetallic layer compounds (IMC) formed after the reflow step. We have shown that Cr-Cu-Au UBM, with a diameter equal to the half of the stencil aperture, ensure the mechanical adhesion of the balls

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Filice, Francesco. "Solutions innovantes d'antennes en bande Ku- et Ka- en technologie d’impression 3-D pour la réalisation des réseaux phasés visant des applications 5G et des communications mobiles par satellite." Thesis, Université Côte d'Azur, 2020. http://www.theses.fr/2020COAZ4023.

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L'utilisation exponentielle d’applications mobiles entraîne une demande en constante croissance pour des débits de données de plus en plus élevés associées à des solutions de télécommunications mobiles à faible coût. Alors que les réseaux 5G en sont encore à leur début, les télécommunications mobiles par satellite (Sat-Com-On-The-Move) peuvent jouer un rôle central dans cette problématique. La bande passante disponible dans les bandes de fréquences Ku- (10,75-14,5 GHz) et Ka- (18-31 GHz) pour ces applications peut être exploitée afin de fournir une connexion internet globale à haut débit et faible coût. Des entreprises comme SpaceX déploient actuellement de grandes constellations de satellites positionnées sur des orbites terrestres basses et pouvant répondre à ces besoins. Néanmoins, le prix et le facteur de forme des terminaux utilisateurs à réflecteur motorisé existants restent les principaux goulots d'étranglement pour rendre ces technologies abordables à une grande partie de consommateurs. La bande passante opérationnelle atteignable par les éléments rayonnants intégrés à faible profil (i.e. réseaux d’antennes à fentes) étant limité, la plupart des solutions existantes divisent la transmission (Tx) et la réception (Rx) dans deux panneaux rayonnants différents ce qui impose un coût relativement élevé pour les utilisateurs finaux. L'objectif de cette thèse consiste à développer des solutions d'antennes innovantes à faible coût et à large bande, notamment des antennes patch à couplage par fente et des antennes à guides d'ondes nervurés fabriqués avec des circuits imprimés standard (PCB) et par impression 3D en métal. Ces antennes sont censées couvrir la totalité de la bande Ku et Ka afin de permettre la création de terminaux utilisateur Sat-Com-On-The-Move à faible encombrement capables d'effectuer à la fois les fonctions Rx et Tx à l'aide d'un seul panneau antennaire. Une attention particulière est accordée à la possibilité d'intégrer ces éléments rayonnants dans de petits réseaux à utiliser comme cellule unitaire pour la réalisation de plus grands, en envisageant la possibilité d'atteindre les niveaux de gain requis par ce type de télécommunications
The increasing use of mobile applications leads to a growing demand for higher data-rates and low-cost mobile telecommunication solutions. While 5G networks are still at their early stages, a central role can be played by the mobile satellite telecommunications (Sat-Com-On-The-Move). The frequency bandwidth available at Ku- (10.75-14.5 GHz) and Ka- (18-31 GHz) bands for these applications can be leveraged in order to provide worldwide, high-speed and low-cost internet connections. Companies like SpaceX are actually deploying large satellite constellations required to work at Low Earth Orbits and offer such services. Nevertheless, the price and the form factor of the traditional motorized reflector-based user terminals remain the main bottlenecks in order to make these technologies affordable to the mass-market consumers. The limited operational bandwidth of the radiating elements integrated in their low-profile alternatives (i.e. slotted waveguide antenna arrays) actually obliges to split transmission (Tx) and reception (Rx) in two different panels, keeping a relatively high cost for the end-users. The objective of this thesis is to develop innovative low-cost and wideband antenna solutions, notably microstrip aperture coupled patch and double ridged waveguide antennas, to be respectively realized by standard Printed Circuit Board (PCB) and metal 3-D printing. These antennas are meant to cover the whole Ku- and Ka- band in order to allow the creation low-profile Sat-Com-On-The-Move user terminals able to perform both Rx and Tx using a single antenna panel. A particular attention is given to the possibility to integrate these radiating element in small arrays to be used as unit cell for the realization of larger ones, envisaging the possibility to achieve the levels of gain required by this kind of telecommunications

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Lucas, Michael David Ian. "Antimicrobial surface coatings via cold spray and 3D printing technologies." Thesis, 2020. https://hdl.handle.net/10539/31283.

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A thesis submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, in fulfillment of the requirements for the degree of Doctor of Philosophy, 2020
Surface contamination and subsequent microbial transmission is a persistent problem in healthcare facilities, contributing to the global pervasion of nosocomial infections and the aggressive prevalence of resistant strains. Touch-contact surfaces, as effective intermediaries for pathogenic transmission, are priority targets for solution development. Polymer metallisation of ABS, PEEK and PC polymers with antimicrobially active copper, silver and zinc metals, via multi-step and multi-material additive manufacturing, for antimicrobial surface coating production, was investigated. Cold spray and polymer 3D printing technologies were, for the first time, integrated for the application of self-sanitising surface coatings. Theoretical modelling, in conjunction with a targeted particle depth-of-penetration model and adapted Taguchi optimisation method, aided cold spray parameter selection. Successful coatings were achieved using a novel independent parameter effects and variation decision framework and a tailored experimental optimisation procedure. Antimicrobial efficacy was evaluated using two, independent, in vitro assays: a diffusion assay and an adapted time-kill assay simulating touch-contact pathogenic exposure. Preliminary prototype trials were also conducted, which included a 3D printed smartphone cover. Enhanced antimicrobial efficacy under both wet and dry contact conditions was observed. In a touch-contact environment, cold spray coatings were found to be five times more biocidal than their respective base metals. A 50% w/w copper-zinc coating on a 3D printed ABS substrate exhibited synergistic bacteriostatic activity: found to be 43% more effective than the combined average activity of copper and zinc coatings against Staphylococcus aureus, Pseudomonas aer-uginosa and Klebsiella pneumoniae. Additional test pathogens included Enterococcus faecalis and Candida albicans. A combination of factors is believed to be responsible for this activity, including the known mechanisms of action of oligodynamic metals, enhanced diffusion of ions and surface topography supporting direct microbial contact, made possible by the novel coating process employed. Antimicrobial activity was not signifi cantly impaired by resistant pathogens: gentamicin-methicillin-resistant S. aureus, azlocillin-carbenicillin-resistant P. aeruginosa and a uconazole-resistant C. albicans. Against these resistant pathogens - under dry, touch-contact conditions - the cold spray coatings achieved complete microbial elimination within 12 min for a copper coating on 3D printed ABS and within 5 min for a copper coating with a 5 wt% silver additive on a copper metal substrate. In response to the global need for alternative solutions to infection control and prevention, these effective antimicrobial surface coatings are proposed
CK2021

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