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Materialval, konstruktion och parametrar för 3D-utskrift / Material selection, design, and parameters for 3D-printsMalmgren, Elina, Olofsson, Ivar January 2024 (has links)
Detta examensarbete handlar om framställandet av en dokumentation för konstruktörer inom området 3D-skrivning. Arbetet är ett uppdrag från elbilstillverkaren Ecoist i syftet att underlätta för företag med begränsad kunskap och erfarenhet inom 3D-utskrifter att utnyttja tillverkningsmetoden för sina produkter. Dokumentationen skall innehålla riktlinjer för materialval, konstruktionsprinciper, och inställningar för 3D-utskrifter. För att begränsa arbetet till tidsramen läggs fokus på en typ av skrivare. Den valda typen är FDM eftersom det är den bedöms vara mest tillgängliga, både i pris och utbud. De material och dess egenskaper som betonas i dokumentationen är ASA, PETG, PLA, PP och TPU. Det huvudsakliga arbetet kommer främst innefatta faktainsamling och sammanställning från befintliga information, men även laborationer med 3D-skrivare. Kapitelindelningen i dokumentationen är strukturerad för att följa konstruktörens arbetsprocess. Den inleds med materialval, fortsätter med konstruktion och avslutas med inställningar för 3D-skrivare. I materialegenskaper behandlas de grundläggande egenskaperna hos olika material som används inom 3D-utskrift, med särskilt fokus på deras hållfasthet, miljöpåverkan, användningsområde samt för- och nackdelar. Konstruktionsriktlinjer handlar om utformning av detaljer, inklusive minsta detaljtjocklek, hantering av överhäng, fasning, efterbearbetning, integrering av fästelement samt toleranser mellan närliggande delar. Fokus ligger på att säkerställa att detaljerna är konstruerade för att vara hållbara och funktionella efter tillverkning med 3D-skrivare. Inställningar för 3D-skrivare handlar om STL-filer, olika typer av ifyllnadsmönster samt vanliga defekter och åtgärder för att motverka dem. Vidare behandlas materialspecifika inställningar för optimal justering av 3D-skrivaren. Vid utformningen av dokumentet läggs mest fokus på utseende och läsbarhet, samt ordning och struktur genom färgval, text/tabellspresentation och anpassandet av dokumentet för både fysiskt och digitalt exemplar. Hela dokumentationen finns i bilaga 1. / This thesis focuses on creating documentation for designers in the field of 3D printing. The project is commissioned by the electric car manufacturer Ecoist with the aim of helping companies with limited knowledge and experience in 3D printing to utilize this manufacturing method for their products. The documentation will include guidelines for material selection, design principles, and 3D printing settings. To fit the project within the given timeframe, the focus is limited to one type of printer. The selected type is FDM, as it is considered the most accessible in terms of price and availability. The materials and their properties emphasized in the documentation are ASA, PETG, PLA, PP, and TPU. The main work will primarily involve gathering and compiling information from existing sources, but also conducting experiments with 3D printers. The chapters in the documentation are structured to follow the designer's workflow. It begins with material selection, continues with design, and concludes with 3D printer settings. In material properties, the basic characteristics of different materials used in 3D printing are covered, with a particular focus on their strength, environmental impact, areas of use, as well as their advantages and disadvantages. Design guidelines involve the configuration of details, including minimum detail thickness, handling of overhangs, chamfering, post-processing, integration of fasteners, and tolerances between adjacent parts. The focus is on ensuring that the details are designed to be durable and functional after manufacturing with a 3D printer. 3D printer settings cover STL files, different types of infill patterns, and common defects along with countermeasures to avoid them. Furthermore, material-specific settings for optimal adjustment of the 3D printer are presented. In the design of the document, the emphasis is on appearance and readability, as well as order and structure through the choice of colors, text/table presentation, and adapting the document for both physical and digital copies. The entire documentation is included in Appendix 1.
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Comparative pilot study of 3D Manufactured and Conventional Manufactured Custom Made Foot Orthotics when looking at Plantar Pressure Distribution and Comfort in adultsMågård-Hansen, Alexander, Sejersen, Camilla Louise January 2024 (has links)
Background 3D manufacturing is a newer technology that shows potential and has gained interest in the world of medical devices. It has been used to produce custom made foot orthotics (CFO)s, but little evidence on the biomechanical effects is available. The literature suggests that the 3D manufactured CFOs (3DMCFO) have comparable outcomes as conventional manufactured CFOs (CMCFO). Purpose The purpose of this pilot study was to investigate biomechanics and comfort in the 3D manufacturing method, because of the lack of biomechanical evidence in literature, and because comfortable orthotics are a prerequisite for an optimal foot orthosis. Methods This pilot project uses a randomized crossover study design to test if there is a difference in plantar pressure distribution and comfort between 3DMCFOs and CMCFOs on two participants (n=2). To investigate the plantar pressure distribution the F-scan® in-shoe sensors was used to measure peak plantar pressures. To evaluate comfort the Orthosis Comfort Score (OCS) was used. Result For both participants similar results of mean peak pressures could be seen in some areas in the two CFOs, where in other areas contradictory results were seen. The comfort in the two CFOs was similar. Conclusion Similarities was seen in plantar pressure distribution and comfort in the two CFOs in both participants. However, the validity and reliability are low because of the low number of participants. / Baggrund 3D print er en nyere produktionsmetode som viser potentiale og har vækket interesse inden for medicinske hjælpemidler. 3D printning er blevet brugt til at producere specialfremstillede fod ortoser (SFO), men der er lav evidens for dens biomekaniske effekt. Litteraturen viser at 3D printede SFOer har sammenlignelige resultater som konventionel produceret SFOer. Formål Formålet med dette projekt var at undersøge biomekanik og komfort for 3D- produktionsmetoden. Dette blev undersøgt fordi der er lidt evidens inden for området, og fordi komfort er en forudsætning for en optimal fod ortose. Metode Dette pilotstudie bruger et randomiseret kontrolleret studie design for at teste om der er en forskel imellem 3D produktionsmetoden og den konventionelle produktionsmetode når der kigges på trykfordeling og komfort i to deltagere (n=2). For at undersøge trykfordeling under foden bruges F- scan® indlæg-sensor, for komfort bruges The Orthosis Comfort Score. Resultat For begge deltagere var der overensstemmelser i de gennemsnitlige høje tryk og i komfort for begge SFOer, hvor der i nogen områder var uoverensstemmelser. Konklusion For de to SFOer, overensstemmelser kunne ses i trykfordelingen under foden og i komfort. Validiteten og pålideligheden for dette projekt er dog ikke højt på grund af det lave deltagerantal.
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Designing PU resins for fibre composite applicationsAl-Obad, Zoalfokkar January 2018 (has links)
This thesis focuses on designing thermoplastic composites with high mechanical properties and a low processing temperature. Thermoplastic composites, which are used in this work, are composed of thermoplastic polyurethane (TPU) matrices and plain woven E-glass fabrics (GFs). TPUs were synthesised with large quantities of hard segments (HS), including 70% and 90%wt HS. The GF-TPU composites manufactured in this study have a melting point of around 175oC. As such, 180oC represents the processing temperature, which was used to produce GF-TPU composites. The influences of HS content and annealing treatment at 80oC on the thermal, dynamic mechanical and mechanical properties of TPU samples and GF-TPU composites with 25% fibre volume fraction (Vf) have been investigated. The highest crystallinity, storage modulus, Tg, yield strength, tensile strength and tensile modulus of all the TPU samples are seen in the TPU/90 samples annealed for 4 days. The TPU/90 samples display higher tensile properties than the TPU/70 and polypropylene (PP) samples, while the PP samples show the greatest elongation at break point. Furthermore, the tensile properties of the TPU/70 and TPU/90 samples are much higher than those of commercial TPUs. As such, annealed GF-TPU/90 composites with 25% Vf present the greatest dynamic mechanical, flexural, and tensile properties. GF-TPU/90 composites with 25% Vf show higher flexural strength than GF-PP composites or GF-polyamide 6 (PA6) composites with the same Vf. The effects of fibre surface treatments on the mechanical properties of GF and GF-TPU/70 composites with 25% Vf have also been studied in this investigation. GF treated with burn-off treatment is found to exhibit the lowest tensile properties. The interfacial adhesion between GF treated by NaOH for 0.5hrs and a TPU/70 matrix is greater than between GF treated by acetone for 5hrs and a TPU/70 matrix. Silanised GF presents greater tensile properties than desized GF. Thus, enhanced interfacial adhesion and tensile, flexural, ILSS and GIC properties are observed in the silanised GF-TPU/70 composites than in the desized GF-TPU/70 composites. GF-TPU/70 composites based on GFs treated by NaOH for 0.5hrs then sized with 0.15%wt. aminosilane display the greatest interfacial adhesion, flexural properties, ILSS and GIC, damage tolerance and impact-damage resistance. Conversely, the lowest interfacial adhesion, GIC, damage tolerance and impact-damage resistance are seen in the GF-PP composites based on 25% Vf as-received GF. There is a significant increase in the tensile and flexural properties of GF-TPU/90 composites with increasing the Vf from 25% to 50%. Moreover, the flexural strength of GF-TPU/90 composites with 50% Vf is not only higher than that of GF-EP composites or GF-vinyl ester composites with normalised 50% Vf, but is also much higher than that of GF-PP composites with 50% Vf. Despite this result, GF-TPU/90 composites with 50% Vf show the lowest fracture toughness, impact-damage resistance and damage tolerance, which are improved by adding 25% and 50%wt. of TPU/70 to the TPU/90 matrix. GF-TPU/90 composites based on a modified matrix have higher GIC, GIIC, impact-damage resistance and damage tolerance than GF-TPU/90 composites based on an unmodified matrix. The GIC, GIIC, impact-damage resistance and damage tolerance of GF-TPU/90 composites based on a modified matrix increase with increasing the percentage of TPU/70. Hence, the highest GIC, GIIC, impact-damage resistance and damage tolerance are seen in the GF-TPU/90 composites based on a modified matrix with 50%wt. of TPU/70.
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Undersökning av sågverks effektivitet med avseende på underhåll : Vikten av en kostnadseffektiv underhållspolicyHansson, Sven, Karlsson, Jeanette January 2006 (has links)
Det finns stora förluster i sågverk som inte framkommer av deras traditionella driftsuppföljnings¬processer. Strategiskt viktigt för organisationen är frågan vad företaget behöver göra för att bli effektivt. I detta arbete diskuteras mätmetoder av effektivitet med avseende på underhåll och hur effektiviteten kan mätas med hjälp av att beräkna den totala utrustningseffektiviteten (OEE). Arbetet beskriver också olika underhållsstrategier och processen med att införa en sådan policy på sågverk. Under en period av sex dagar beräknas OEE på fem sågverk. Resultatet var att OEE värdet i snitt var runt 50 procent, som är ganska lågt. Genom att applicera en kostnadseffektiv underhållspolicy kan företaget öka sitt OEE värde och få en mer effektiv process. Detta kan göras genom att en policyn minskar de övergripande kostnaderna relaterade till de sex stora förlusterna. Diskussion förs också kring avvikelserna/stoppen och hur orsakerna till dessa kan härledas genom analyser med t.ex. Ishikawadiagram. Arbetet lyfter fram att ett systematiskt förbättringsarbete skulle ge nästan ett fördubblat kapacitetsutnyttjande för sågverken utan några större investeringar. I arbetet beskrivs hur sågverken kan bli framgångsrikare med detta genom att välja en kostnadseffektiv underhållspolicy. / There are several big losses in sawmills that are not addressed by the traditional operation feedback systems. It is strategic significant for organizations to address the question what need to be done in order to bee more effective. This work discusses methods of measurement the effectiveness with respect to maintenance and how the effectiveness can be measured by assessing the Overall Equipment Effectiveness (OEE). The work also emphasizes on maintenance strategies and the process of implementing such a policy in sawing mills. During a period of six days assessments of OEE were made in five different sawmills. The results were that OEE in general were about 50 percent, which is considered low. By implementing a cost-effective maintenance policy, it will lead to increase the value of OEE for the process. Using a policy that will decrease the overall costs related to the six big looses could do these. Discussions the production stoppages and how these can be analyzed by using different tools, such as Ishikawa diagram are addressed. The work highlights that a systematic improvement work would increase appreciably the capacity utilized without any large investments. This study also describes how sawmills can be successful when increasing their effectiveness by selecting a cost-effective maintenance policy for their process.
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Undersökning av sågverks effektivitet med avseende på underhåll : Vikten av en kostnadseffektiv underhållspolicyHansson, Sven, Karlsson, Jeanette January 2006 (has links)
<p>Det finns stora förluster i sågverk som inte framkommer av deras traditionella driftsuppföljnings¬processer. Strategiskt viktigt för organisationen är frågan vad företaget behöver göra för att bli effektivt. I detta arbete diskuteras mätmetoder av effektivitet med avseende på underhåll och hur effektiviteten kan mätas med hjälp av att beräkna den totala utrustningseffektiviteten (OEE). Arbetet beskriver också olika underhållsstrategier och processen med att införa en sådan policy på sågverk. Under en period av sex dagar beräknas OEE på fem sågverk. Resultatet var att OEE värdet i snitt var runt 50 procent, som är ganska lågt. Genom att applicera en kostnadseffektiv underhållspolicy kan företaget öka sitt OEE värde och få en mer effektiv process. Detta kan göras genom att en policyn minskar de övergripande kostnaderna relaterade till de sex stora förlusterna. Diskussion förs också kring avvikelserna/stoppen och hur orsakerna till dessa kan härledas genom analyser med t.ex. Ishikawadiagram. Arbetet lyfter fram att ett systematiskt förbättringsarbete skulle ge nästan ett fördubblat kapacitetsutnyttjande för sågverken utan några större investeringar. I arbetet beskrivs hur sågverken kan bli framgångsrikare med detta genom att välja en kostnadseffektiv underhållspolicy.</p> / <p>There are several big losses in sawmills that are not addressed by the traditional operation feedback systems. It is strategic significant for organizations to address the question what need to be done in order to bee more effective. This work discusses methods of measurement the effectiveness with respect to maintenance and how the effectiveness can be measured by assessing the Overall Equipment Effectiveness (OEE). The work also emphasizes on maintenance strategies and the process of implementing such a policy in sawing mills. During a period of six days assessments of OEE were made in five different sawmills. The results were that OEE in general were about 50 percent, which is considered low. By implementing a cost-effective maintenance policy, it will lead to increase the value of OEE for the process. Using a policy that will decrease the overall costs related to the six big looses could do these. Discussions the production stoppages and how these can be analyzed by using different tools, such as Ishikawa diagram are addressed. The work highlights that a systematic improvement work would increase appreciably the capacity utilized without any large investments. This study also describes how sawmills can be successful when increasing their effectiveness by selecting a cost-effective maintenance policy for their process.</p>
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Povrchové změny v závislosti na parametrech FDM tisku / Surface changes based on FDM printing parametersČada, Jiří January 2016 (has links)
This thesis deals with a construction of modified RepRap 3D printer Rebel II which operates with Fused Deposition Modeling technology and selection of suitable criterion for printing. It mainly focuses on the temperature of the material being printed and speed of printing for three selected materials. Materials were selected based on availability in the market and their application. An experiment, focusing on surface changes of products as well as on the look of a fibre after passing through a nozzle, was performed.
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Effect of Inclusion of Nanofibers on Rolling Resistance and Friction of Silicone RubberHutama, Chapin 26 July 2019 (has links)
No description available.
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Design, implementering och evaluering av en AI accelerator med Google Coral Dual Edge TPU / Design, implementation and evaluation of an AI accelerator using Google Coral Dual Edge TPUBurwall, Oscar January 2023 (has links)
Den snabbt växande utvecklingen av AI-baserade applikationer och den stora mängden data dessa applikationer behandlar ställer ökade krav på prestanda och optimering av datorsystemen. För att tillfredsställa de växande datorbehoven används hårdvaruacceleratorer som förbättrar databehandlingshastigheten genom att avlasta den befintliga utrustningen genom att hjälpa till med uppgifter och komplexa beräkningar. De befintliga lösningarna som används i dagsläget är kostsamma och MT-FoU på Umeå Universitetssjukhus efterfrågar därför en alternativ lösning i form av att kombinera mindre integrerande acceleratorer på ett större PCIe-kort. I detta examensarbete designas och implementeras en AI-accelerator bestående av fyra Google Coral Dual Edge TPU M.2 på ett 16x PCIe-kort. Arbetet genomfördes på MT-FoU och målet med examensarbetet var att undersöka om den tilltänkta konstruktionen kan förbättra prestandan hos AI-baserade system och fungera som ett billigare alternativ i verksamheten. Schemaritning och PCB-design utfördes i KiCad och information om gränssnitt och komponenter hämtades främst från tillverkares hemsidor och datablad. Kretsen består i huvudsak av fyra stycken M.2 E key kontaktdon, en 16port/16lane packetswitch och en 16x PCIe-anslutning. Switchen delar upp banorna från PCIe porten så att Edge TPU’erna kan anslutas parallellt i M.2 kontakterna. Edge TPU’erna använder pipelineparallellism för att fördela arbetsuppgifter på varje TPU så att större, mer komplexa program kan exekveras. Vid monteringen av kretskortet uppstod problem med fastlödningen av vissa komponenter. För att undvika att dessa problem uppstår och möjliggöra avlägsnandet av dessa felkällor bör montering istället beställas av fabrik där lödrobot finns tillgängligt. På grund av att tiden för kursen tog slut hann en sådan beställning inte göras och evaluering av den framtagna designen var därför inte möjlig att genomföra. Den design som togs fram var dock betydligt billigare än de existerande lösningarna och med pipelineparallellism förväntas designen kunna utföra komplexa beräkningar och därmed förbättra prestandan i befintliga system. / The rapidly growing development of AI-based applications and the large amount of data these applications process place increased demands on the performance and optimization of conventional computer systems. To satisfy these growing computing requirements, hardware accelerators are used to improve the data processing speed by offloading the existing equipment by executing models and complex calculations. The existing solutions currently used are costly and MT-R&D at Umeå University Hospital is therefore requesting an alternative solution by combining smaller integrating accelerators on a larger PCIe card. In this thesis, an AI accelerator using four Google Coral Dual Edge TPU M.2 on a 16x PCIe card is designed and implemented. The work was carried out at MT-R&D and the goal of the thesis was to investigate whether the intended design can improve the performance of AI-based systems and serve as a cheaper alternative in the institution. Schematic and PCB were designed in KiCad and information on interfaces and components was obtained from manufacturers' websites and data sheets. The circuit’s main components are four M.2 E key connectors, a 16port/16lane packet switch and a 16x PCIe connection. The switch divides the lanes from the PCIe port so that the Edge TPUs can be connected in parallel in the M.2 connectors. The Edge TPUs use pipeline parallelism to distribute models across each TPU so that larger, more complex programs can be executed. When assembling the circuit board, problems arose with the soldering of certain components. In order to avoid these sources of error, assembly should instead be ordered from a factory where a soldering robot is available. Due to the fact that the time for the course ran out, such an order could not be placed and evaluation of the design was therefore not possible to carry out. However, the design that was produced was significantly cheaper than the existing solutions and by using pipeline parallelism, the design is expected to be able to perform complex calculations and thus improve the performance of existing systems.
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MY CLOTHING IS ME: Embracing ADHD in Traditional Qatari ApparelAbdulla, Rabab 01 January 2019 (has links)
Children diagnosed with Attention Deficit Hyperactive Disorder (ADHD) are often secluded from society, as the condition is perceived to be a defect. These children constantly fidget, move, lose track of time, and forget to complete tasks, leading them to struggle within existing social environments. Additionally, in Qatar there is a need to educate society about ADHD. This research explores wearable solutions that alter behaviors through physical interactions and sensory engagements. In response to the challenges faced by ADHD, Qatari traditional attire has been customized to support children with time management, and communication between child, parent, and society. Additionally, these wearables challenge Qatari perspectives surrounding existing health conditions in Qatar. Design outcomes consists of clothing elements, driven and shaped by the experiences of ADHD children, their physical behavior, their senses like touch, smell and sight. It addresses the daily conduct of the ADHD child, and the relationship of the child and parent. By challenging existing norms and analyzing the Qatari traditional clothing (the Thobe, the Abaya and the Prayer Bead), design outcomes have been realized by experimenting and playing with materials, prototyping and 3D printing on fabric. Existing functions of zippers, pockets, beads, cuffs and technical construction of the outfit have been redesigned and reconstructed.
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Study Of Belts Acting As A Positioning System For Interconnected Gripping Tools In Tube Filling Machines / Studie av remmar verkande som positioneringssystem till sammanlänkade gripvertyg hos tubfyllingsmaskinerHohner, Robin, André, Ekengren January 2018 (has links)
The task performed in this assignment is to improve the reliability of Norden Machinery ABs product family. This is to be done by examining and replacing the belt used to stop the spreading of tubes from ingoing shipping crate to the infeed of the machine. The way that this was approached was by testing different candidates on a spectrum of their rigidity to find if a flexible or more rigid belt would perform better than the current context of the system. The testing was conducted for a period of 4 weeks and results were gathered by examining damages to the belts by the use of microscope. After the damage had been analyzed the conclusion was drawn that flexible alternatives seems to perform the task better than their rigid counterparts however more work is needed in the fields regarding the fastening and operation of the machine to use the best suited candidates derived from this test, the monolithic belt FMT-02TXCT-U1.
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