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BTH har i dagens läge en önskan om att ha ett effektivare sätt att fästa ett arbetsstycke som kommer att bearbetas av fräsmaskinen. Det mest lämpliga alternativet anses då vara ett vakuumbord. Syftet med detta examensarbetet är att undersöka framtagning och utveckling av vakuumbord. BTH hade då också en kravlista på vad bordet skulle kunna klara av att göra. Bordet skall ha en total arbetsyta på 400 x 400 mm, den ska kunna hålla fast arbetsstycken som består av trä och plast som ska genomfräsas. Den skall även ha en skyddsbräda som skyddar bordet från förslitningar över tiden. Det undersöktes vilket material som ansågs lämpligast att skapa vakuumbordet i, hur processen att fästa arbetsstycket skulle kunna förbättras samt det bästa sättet att optimera funktioner och dimensioner på genom att ta hänsyn till bordets höjd och volym. För att uppnå det målet så kommer en undersökning utföras kring vad ett vakuumbord är, hur de fungerar och varför de är så eftertraktade. Efteråt påbörjas en idégenereringsfas där olika konceptförslag kommer granskas och utvecklas. Efter att ett koncept har valts ut så kommer modellering, beräkning och tillverkningen av prototyperna att påbörjas. Tre prototyper kommer skapas under arbetets gång och prototyperna kommer genomgå en rad olika tester för att granska prototypens sugkraftsstyrka och om de kan hantera vakuumtrycket. Efter att testerna har slutförts så ska de analyseras och utvärderas för att se om de kan utvecklas och förbättras ytterligare. Efter att prototyperna byggts, testerna och utvärderingarna slutförts så kommer det etableras om vakuumbordet fungerar eller inte. Från detta så beslutades det att plywood och MDF är de bästa materialen att bygga i, att nya fästningsmetoder testades och funkar, men uppfyllde inte alla kundens krav. Slutgiltigen så har bordets höjd optimerats på bästa sätt, men att det kan optimeras ytterligare. Med det som har tagits fram så kan rapporten visa att flera utvecklingsmöjligheter har prövats, att kraven har uppfyllts och flera idéer har föreslagits för framtida utveckling av vakuumbordet. / BTH has today a desire to have a more efficient way of attaching a workpiece that will be worked on by the milling machine. The most suitable alternative for this task is considered to be a vacuum table. The purpose of this thesis is to investigate the production and development of vacuum tables. BTH also has a list of requirements for what the table should be able to do. The table will have a total work surface of 400 x 400 mm, it will be able to hold workpieces that consist of wood and plastic and it will have a protection board that protects the table from wear and tear over time. In the report it was examined which material is considered most suitable for creating the vacuum table, how the process of attaching the workpiece could be improved and the best way to optimize functions and dimensions with respect to the table's height and volume. To achieve that goal, research will be conducted on what vacuum tables are, how they work and why they are so sought after. Afterwards, an idea generation phase will begin where various concept proposals are investigated and developed. After a concept is selected, modelling, calculation and production of the prototypes will begin. Three prototypes will be created during the work and the prototypes will undergo a series of different tests to examine the prototypes suction power and whether the table can handle the vacuum pressure. After the tests the prototypes will be analysed and evaluated to see if they can be further developed or improved. When the prototype constructions, tests and evaluations are completed it should be easy to establish if the vacuum table works or not. From this it was decided that plywood and MDF are the best materials to build in, that new fastening methods were tested and worked, but did not meet all the customer's requirements. Finally, the table has been optimized in the best way, but it can be further optimized. With what has been produced the report shows that several development possibilities have been tried, that the requirements have been met and several ideas have been proposed for future development of the vacuum table.

I klädindustrin är materialval och beslut om produkter en viktig del av produktutvecklingsprocessen som påverkar design, kostnad, känsla samt estetik i en produkt. Materialvalsprocessen har blivit mer komplex och utseende samt kvalitet konkurrerar nu också med hållbarhet. Många aspekter är därför viktiga att balansera vid beslutsfattande. Det finns metoder, men om och hur de används av svenska klädföretag är relativt outforskat. Artificiella intelligenta-system som kan användas i beslutsfattandet finns tillgängliga idag och används redan i olika områden inom klädindustrin. Det finns också AI-system för materialval, men ännu inte i klädindustrin. Syftet med denna studie är att studera beslutsfattande inom svenska klädföretag avseende hållbara produkt- och materialval samt om AI skulle kunna stödja processen. Semistrukturerade intervjuer genomförda med två svenska klädföretag användes i denna studie för att besvara två forskningsfrågor kopplade till syftet tillsammans med en iterativ litteraturstudie. Studien visar att svenska klädföretag inte använder några speciella verktyg eller kända metoder vid beslutstagande gällande material och produkter för att uppnå deras hållbarhetsmål. Ofta är det intuition och erfarenhet som ligger bakom beslut och val men det finns även kravspecifikationer för varje produkt med krav som måste vara uppfyllda för att beslutet om materialval ska tas. I dag använder företagen inga AI-system men enligt teorin finns det några AI-metoder som skulle kunna implementeras inom material- och produktbeslut där det gäller kvantitativa aspekter, exempelvis vattentäthet. Dock kan inte något AI-system i dag ersätta människans förmåga att ta beslut vad gäller mer kvalitativa egenskaper, såsom känslan av ett material. / In the apparel industry, material choice and decisions regarding products are an important part of the product development process, influencing design, cost, feeling and aesthetic of a product. The material choice process is becoming more complex and look along with quality now also competes with sustainability. Many aspects are therefore important to balance when making decisions. There are methods, but it is unclear if and how they are used by Swedish apparel companies. Artificial Intelligence systems that can be used in decision making are available today, and already in use in different areas within the apparel industry. There are also AI-systems for material choice, but not yet in the apparel industry. The purpose of this study is to study decision making within Swedish clothing companies regarding sustainable product and material choices and whether AI could support the process. Semi structured interviews conducted with two Swedish apparel companies were used to answer two research questions, together with an iterative literature study. The study shows that Swedish apparel companies do not use any special tools or known methods while making decisions regarding material and products in order to achieve their sustainability goals. Often intuition and experience is behind making a decision or choice, but also specifications regarding each product with requirements that have to be fulfilled. Today the asked companies do not use AI-systems for making decisions regarding materials or products, but according to literature, there are some methods that possibly could be implemented regarding quantitative aspects such as water permeability. However, there does not seem to be any AI-systems today that can replace human’s ability to make decisions concerning the qualitative aspects such as the feeling of a material.

<p dir="ltr">Acoustic guitar soundboard material selection is based on selective evaluations that have been developed over centuries. These traditional practices are not conducive to the guitar industry we experience today because the supply of traditionally acceptable soundboard wood has decreased greatly. The purpose of this research was to develop an objective wood selection metric to determine the sound quality of an acoustic guitar’s soundboard. The metric would replace the subjective evaluations traditionally used to select materials for acoustic guitar soundboards.</p><p dir="ltr">The acoustic properties of sound radiation coefficient, material’s speed of sound, resonance and damping and the material properties of longitudinal and radial elastic modulus, density, and specific modulus were used in an attempt to construct a material selection metric. These variables were selected because the literature review revealed that these were the most critical variables in determining sound quality. The gaps in the literature were testing and analyzing samples that represented the true dimensions of an acoustic guitar soundboard blank and forming the metric. The literature revealed that the previous experimental studies did not have the appropriate test sample dimensions that correspond to the test samples evaluated by the subjective methods.</p><p dir="ltr">The methodology was carried out by using the objective testing counterparts to the subjective assessments found in the literature review. Instrumented hammer tap testing collected data to determine damping and resonance frequencies. A three-point static bending test collected data for longitudinal and radial elastic modulus. Mass and dimension measurements were recorded to calculate density. Calculations were done to compute the acoustic properties and specific modulus of the test samples. These variables were put into a table and underwent statistical analysis in the form of predictor correlation and logistical regression. The experimental variables were modeled against the subjective evaluation of an expert on the usability of the test samples.</p><p dir="ltr">Statistical analysis proved that the dataset did not show any significant separation between “good” or “bad” test samples or a significant correlation between the usability of the test sample and the variables in the dataset. The methodology did not produce an objective material selection metric to determine the sound quality of an acoustic guitar’s soundboard. Future research should include a wider range of measured frequencies and the collection of time domain data.</p>

In der vorliegenden Arbeit werden Holzwerkstoffe im statischen Biegeversuch und im Schlagbiegeversuch vergleichend geprüft. Ausgewählte Holzwerkstoffe werden thermisch geschädigt, zudem wird eine relevante Kerbgeometrie geprüft. Ziel der Untersuchungen ist die Eignung verschiedenartiger Werkstoffe für den Einsatz in sicherheitsrelevanten Anwendungen mit Schlagbelastungen zu prüfen. Hierzu werden zunächst die Grundlagen der instrumentierten Schlagprüfung und der Holzwerkstoffe erarbeitet. Der Stand der Technik wird dargelegt und bereits durchgeführte Studien werden analysiert. Darauf aufbauend wird eine eigene Prüfeinrichtung zur zeitlich hoch aufgelösten Kraft-Beschleunigungs-Messung beim Schlagversuch entwickelt. Diese wird anhand verschiedener Methoden auf ihre Eignung und die Messwerte auf Plausibilität geprüft. Darüber hinaus wird ein statistisches Verfahren zur Überprüfung auf ausreichende Stichprobengröße entwickelt und auf die durchgeführten Messungen angewendet. Anhand der unter statischer und schlagartiger Biegebeanspruchung ermittelten charakteristischen Größen, wird ein Klassenmodell zum Werkstoffvergleich und zur Werkstoffauswahl vorgeschlagen. Dieses umfasst integral die mechanische Leistungsfähigkeit der geprüften Holzwerkstoffe und ist für weitere Holzwerkstoffe anwendbar. Abschließend wird, aufbauend auf den gewonnenen Erkenntnissen, ein Konzept für die Bauteilprüfung unter Schlagbelastung für weiterführende Untersuchungen vorgeschlagen. / In the present work wood-based materials are compared under static bending load and impact bending load. Several thermal stress conditions are applied to selected materials, furthermore one relevant notch geometry is tested. The objective of these tests is to investigate the suitability of distinct wood materials for security relevant applications with the occurrence of impact loads. For this purpose the basics of instrumented impact testing and wood-based materials are acquired. The state of the technology and a comprehensive analysis of original studies are subsequently presented. On this basis an own impact pendulum was developed to allow force-acceleration measurement with high sample rates. The apparatus is validated by several methods and the achieved signals are tested for plausibility. A general approach of testing for adequate sample size is implemented and applied to the tested samples. Based on the characteristic values of the static bending and impact bending tests a classification model for material selection and comparison is proposed. The classification model is an integral approach for mechanical performance assessment of wood-based materials. In conclusion a method for impact testing of components (in future studies) is introduced.

Foram estudados dois tipos de aços, aço convencional ZAR 230 (ZAR - Zincagem de alta resistência) e aço microligado ZSTE 380 (segundo norma SEW 093), sendo que foram avaliadas as suas propriedades mecânicas visando a substituição do aço convencional por aço microligado na estrutura tubular de uma carroceria para veículos de transporte coletivo de passageiros. O aço convencional vem sendo utilizado pela indústria de carrocerias há vários anos, já o aço microligado é utilizado basicamente em estruturas específicas que requeiram boas propriedades mecânicas e conseqüentemente redução de peso. A análise de viabilidade para a substituição de aço convencional por aço microligado em um módulo estrutural completo requereu uma série de ensaios: ensaios padronizados em laboratório foram executados para avaliação de suas principais propriedades mecânicas e químicas; ensaios de nós estruturais submetidos a uma carga forneceram informações para o uso em software de elementos finitos tanto para execução de cálculos estruturais, quanto para calibração de resultados. Os módulos estruturais foram preparados de acordo com as regulamentações ECE R66-00 (mercado europeu) e CONTRAN 811/96 (mercado brasileiro) e foram ensaiados exaustivamente até se obter o melhor resultado de deslocamento comparativamente aos dois materiais analisados. A validação da estrutura tubular foi obtida com a utilização do software Ansys Workbench 9.0 e a confecção de estrutura representativa de uma carroceria ensaiada conforme regulamentação CONTRAN 811/96. / Submitted by Marcelo Teixeira (mvteixeira@ucs.br) on 2014-05-05T19:51:22Z No. of bitstreams: 1 Dissertacao Magnus Geder Henz Cruz.pdf: 4706762 bytes, checksum: 44526b5417018356b3a33f57c828c75e (MD5) / Made available in DSpace on 2014-05-05T19:51:22Z (GMT). No. of bitstreams: 1 Dissertacao Magnus Geder Henz Cruz.pdf: 4706762 bytes, checksum: 44526b5417018356b3a33f57c828c75e (MD5) / Two kinds of steel were studied, conventional steel ZAR 230 (a standard for high strength galvanizing) and microalloyed steel ZSTE 380 (according to the regulation SEW 093). The study of its mechanical properties aimed to replace the steel for microalloyed steel in bodywork s tubular structure for collective transport vehicles of passengers. The conventional steel has been used for the bodywork industry for years, and the microalloyed steel is basically used in specific structures, those who require good mechanical properties and mass reduction. The analysis of the feasibility for the replacement of conventional steel for microalloyed steel in a complete structural model requires a series of tests. Lab tests were done to evaluate their main mechanical and chemical properties. The tests of the structural nodes and the structural behaviour when subjected to a load provided information to be used in the finite elements method software to do structural calculation and to calibrate the results. The structural modules were prepared according to the regulations ECE R66-00 (European market) and CONTRAN 811/96 (Brazilian market) and these modules were tested exhaustively to achieve the best displacement between the two materials that were analysed comparatively. The validation of the tubular structure was obtained using the software Ansys Workbench 9.0 and the production of the representative structure of a bodywork tested according the regulation CONTRAN 811/96.

Foram estudados dois tipos de aços, aço convencional ZAR 230 (ZAR - Zincagem de alta resistência) e aço microligado ZSTE 380 (segundo norma SEW 093), sendo que foram avaliadas as suas propriedades mecânicas visando a substituição do aço convencional por aço microligado na estrutura tubular de uma carroceria para veículos de transporte coletivo de passageiros. O aço convencional vem sendo utilizado pela indústria de carrocerias há vários anos, já o aço microligado é utilizado basicamente em estruturas específicas que requeiram boas propriedades mecânicas e conseqüentemente redução de peso. A análise de viabilidade para a substituição de aço convencional por aço microligado em um módulo estrutural completo requereu uma série de ensaios: ensaios padronizados em laboratório foram executados para avaliação de suas principais propriedades mecânicas e químicas; ensaios de nós estruturais submetidos a uma carga forneceram informações para o uso em software de elementos finitos tanto para execução de cálculos estruturais, quanto para calibração de resultados. Os módulos estruturais foram preparados de acordo com as regulamentações ECE R66-00 (mercado europeu) e CONTRAN 811/96 (mercado brasileiro) e foram ensaiados exaustivamente até se obter o melhor resultado de deslocamento comparativamente aos dois materiais analisados. A validação da estrutura tubular foi obtida com a utilização do software Ansys Workbench 9.0 e a confecção de estrutura representativa de uma carroceria ensaiada conforme regulamentação CONTRAN 811/96. / Two kinds of steel were studied, conventional steel ZAR 230 (a standard for high strength galvanizing) and microalloyed steel ZSTE 380 (according to the regulation SEW 093). The study of its mechanical properties aimed to replace the steel for microalloyed steel in bodywork s tubular structure for collective transport vehicles of passengers. The conventional steel has been used for the bodywork industry for years, and the microalloyed steel is basically used in specific structures, those who require good mechanical properties and mass reduction. The analysis of the feasibility for the replacement of conventional steel for microalloyed steel in a complete structural model requires a series of tests. Lab tests were done to evaluate their main mechanical and chemical properties. The tests of the structural nodes and the structural behaviour when subjected to a load provided information to be used in the finite elements method software to do structural calculation and to calibrate the results. The structural modules were prepared according to the regulations ECE R66-00 (European market) and CONTRAN 811/96 (Brazilian market) and these modules were tested exhaustively to achieve the best displacement between the two materials that were analysed comparatively. The validation of the tubular structure was obtained using the software Ansys Workbench 9.0 and the production of the representative structure of a bodywork tested according the regulation CONTRAN 811/96.

The AK4 rifle serves as the primary weapon for the Home Guard, an integral part of the Swedish Armed Forces. Introduced in 1964, the AK4 is the Swedish version of the Heckler &amp; Koch G3 and functions as a fully automatic assault rifle. Among its components, the handguard holds significant importance, providing stability, improving accuracy and control, and protecting the user from heat generated by the barrel. Recognizing the need for optimization, an employee from the ALTEN Group, possessing military experience and expertise in the AK4, launched a project to enhance the ergonomics and versatility of the handguard in a cost-effective manner. This initiative stems from the excessively high cost of commercially available handguards, making them financially unviable for replacing the original handguard of every AK4 used by the Home Guard personnel. This project aims to design and develop a next-generation handguard for the AK4 rifle that addresses the current limitations of the existing handguard. The primary focus is improving the shooter’s performance by establishing a comfortable shape of the handguard, reducing the weight, and enhancing its compatibility with accessories. Additionally, the aim is to ensure the handguard is cost-effective for mass production and meets the requirements set by the Swedish Defense Materiel Administration. To achieve the aims, interviews and a comprehensive user testing study was conducted, collecting quantitative data in the form of participant ratings and rankings for different design concept while also gathering qualitative data through participant feedback that highlighted specific design features contributing to comfort. Additionally, a systematic material selection process was performed, involving the analysis and ranking of various materials based on properties such as weight, price, and specific mechanical properties. Furthermore, the manufacturing analysis relied mainly on conversations with industry experts possessing expertise in the field of plastic manufacturing. Upon conducting a detailed analysis, it has been determined that the ideal configuration for the final product is an octagonal shape. After careful evaluation, Polyamide 6 reinforced with 30% glass fibers has emerged as the most suitable material choice for the handguard. This material had the optimal balance between mechanical properties, thermal performance, durability, cost-effectiveness, and environmental impact. To produce 50,000 handguard units, the recommended manufacturing method was injection molding due to its compatibility with mass production and the advice received from industry experts. Considering the design and selected material, a substantial number of the requirements outlined by FMV could be fulfilled by conducting both theoretical analyses and practical experiments.

Denna studie syftar till att utveckla och analysera en prototyp av ett återanvändningsbart trosskydd för kvinnor. Genom att undersöka passform, komfort och hanterbarhet ur ett användarperspektiv, samt jämföra två olika designmodeller (i polyamidspets och polyamidtrikå) med konventionella trosskydd, strävar studien efter att identifiera framgångsfaktorer för återanvändningsbara trosskydd. Marknadsundersökningar och forskningsgenomgångar användes för att skapa en grundläggande förståelse för forskningsområdet samt underlag för konstruktionsarbetet. Prototyper utvecklades och producerades. En testgrupp av sex deltagare genomförde en veckas avprovning av prototyperna och utvärderades med hjälp av kvalitativa frågor. Resultaten visade att trosskydden generellt ansågs ha bra längd och bredd oavsett designmodell. Dock rapporterade flera respondenter skav, oavsett vilken modell de använde. Åsikterna om estetik varierade och ingen generell slutsats kunde dras. Resultaten ger insikter i respondenternas upplevelser av passform, komfort och hanterbarhet hos trosskyddet. Trots viss variation i åsikterna finns det mönster och konsensus som kan vägleda framtida produktutveckling och förbättringar. Sammantaget kan detta examensarbete verka som en förstudie för vidare studier om textila återanvändningsbara trosskydd. / This study aims to develop and analyze a prototype of a reusable panty liner for women. By examining fit, comfort and manageability from a user perspective, as well as comparing two different design models (in polyamide lace and polyamide tricot) with conventional panty liners, the study aims to identify success factors for reusable panty liners. Market surveys and research briefings were used to create a basic understanding of the research area as well as a basis for the design work. Prototypes were developed and produced. A test group of six participants completed a one-week trial of the prototypes and was evaluated using qualitative questions. The results showed that the panty liners were generally considered to have a good length and width regardless of the design model. However, several respondents reported chafing, regardless of the model they used. Opinions about aesthetics varied and no general conclusion could be drawn. The results provide insights into the respondents' experiences of fit, comfort and manageability of the panty liner. Despite some variation in opinion, there are patterns and consensus that can guide future product development and improvements. Overall, this thesis can be used as a preliminary study for further studies on textile reusable panty liners.

Syftet med denna studie var att undersöka klimat- och kostnadseffektiva lösningar för att minska kontorsbyggnaders påverkan på miljön. Byggnader står för en betydande del av Sveriges klimatpåverkan och kostnader, det finns därav behov av att hitta sätt att reducera den påverkan. Teorin som låg till grund för studien var livscykelanalys och livscykelkostnad, som tar hänsyn till klimatpåverkan och kostnader genom hela byggnadens livscykel. Metoden som användes var litteraturstudie, där tidigare forskning och studier analyserades. Diskussion fördes även med sakkunniga personer inom ämnet för att identifiera lösningar för att minska klimatpåverkan och kostnader i byggnader. En hypotetisk fallstudiebyggnad skapades där klimat- och kostnadseffektiva åtgärder implementerades. Genom att titta på byggnadsdelarna stomme, klimatskal, isolering och dess inverkan på energianvändning i en kontorsbyggnad identifierades olika åtgärder som kunde minska klimatpåverkan och kostnader. Dessa inkluderar användning av återvunnet material och minskad energiförbrukning genom förbättrade isoleringsegenskaper. Ytterligare undersöktes val av material och teknik vilket anses hållbara och energieffektiva. Resultatet visar att byggnadsmaterialen har störst påverkan på klimat och kostnaden under Produkt- och Byggproduktionsskedet, medan energiförbrukningen har störst påverkan under skedet Driftenergi i Användningsskedet. De klimatåtgärder som framstår som mest framstående och optimala lösningar för vår fallstudiebyggnad inkluderar användningen av kostnadseffektiva solceller på taket (Åtgärd 7), isolering av ytterväggarna med PIR-isolering (Åtgärd 5), tilläggsisolering av ytterväggarna med EPS-isolering (Åtgärd 3) samt minskat materialspill på byggarbetsplatsen med 25%. Dessa lösningar visar sig inte bara ha en betydligt lägre klimatpåverkan, utan även en mer fördelaktig kostnadseffektivitet över hela livscykeln för fallstudiebyggnaden. / The purpose of this study was to investigate climate and cost-effective solutions to reduce the environmental impact of office buildings. Buildings account for a significant portion of Sweden's climate impact and costs, and there is a need to find ways to reduce this impact. The theoretical framework underlying the report was life cycle analysis and life cycle cost, which consider the climate impact and costs throughout the building's life cycle. The method used was a document study, where previous research and studies were analyzed. A hypothetical case study building was created, where climate- and cost-effective measures were implemented. By examining the building components such as the structure, envelope, insulation, and their impact on energy consumption in an office building, various measures were identified to reduce climate impact and costs. Additionally, the selection of sustainable and energy-efficient materials and technologies was investigated. The results show that building materials have the greatest impact on the environment and cost during the Production and Installation stages, while energy consumption has the greatest impact during the Operational energy use module in the Use stage. The climate measures that stand out as optimal solutions include the use of cost-effective solar panels on the roof (Measure 7), insulating the outer walls with PIR insulation (Measure 5), additional insulation of the outer walls with EPS insulation (Measure 3), and reducing material waste at the construction site by 25%. These solutions not only demonstrate significantly lower climate impact but also exhibit a more advantageous cost-effectiveness over the entire lifecycle.