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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Material and Product Design Integration: Establishing Relationships between Design Variables of Both Domains

Lu, Wen Feng, Deng, Y.-M. 01 1900 (has links)
Due to the increasing demand of application-specific and/or multi-functional materials, it is necessary to integrate material design and product design. To support such design integration, this paper proposes a methodology to establish the relationships of both material design variables and product design variables. These variables include the required system performances and/or other evaluation criteria, and the relevant system loadings and attributes, where the attributes include both the product structural attributes and the material properties. This is achieved by modeling the behaviors of the product and those of the used material, and identifying the dependencies between the relevant design variables from the behaviors. The variable relationships can then be used to solve various design problems, such as design evaluation, evaluation and optimization of critical design variables, and so on. A design case study is also conducted to illustrate the proposed methodology and its usefulness. / Singapore-MIT Alliance (SMA)
82

Foldable pedelec

Truden, Mark January 2013 (has links)
This master thesis project is about easier commuting in a more eco-friendly way thus a new foldable pedelec - pedal electric cycle was created. The idea is that the commuters are able to fold their bicycle to a convenient size and store it under the desk in the office, in a trunk of a car, or even brought on a bus if used as a connecting transport. It incorporates the latest ergonomic, safety, display and drivetrain features in combination with a sleek single-fork design. This enables the pedelec to be folded more conveniently and save additional space. To appeal to a wider range of users they are given the opportunity to choose their own colour codes and personalize their own foldable pedelec.
83

Product Design of Wheat Straw Polypropylene Composite

Fatoni, Rois January 2012 (has links)
The use of wheat straw and other agricultural by-product fibers in polymer composite materials offers many economical and environmental benefits. Wheat straw has been recently commercialized as new filler for polypropylene thermoplastic composites in automotive applications. However, to expand its application in the automotive industry and other sectors where highly-engineered materials are needed, a systematic database and reliable composite property models are needed. For this purpose, this research was systematically conducted. A product design approach is used in studying wheat straw polypropylene (WS-PP) composite. A set of thermoplastic composite specifications relevant to several automotive parts was used as a basis for the customer needs which give the direction to the entire product design of thermoplastic composites based on polypropylene and straw. Straw fibers were produced by grinding and sieving (without any other treatment). These fibers were used in the formulation of polypropylene thermoplastic composites to understand the variable that can contribute to minimize production cost, maximize product performance and maximize wheat straw utilization (fraction of renewable material). The variation in chemical composition due to plant variety (parts of the plant, location of harvesting and seasonality), the bonding incompatibility between hydrophobic polypropylene matrix and hydrophilic straw fiber, along with the heterogeneity of fiber size and shape, has made wheat straw polypropylene composite a complex system. This complexity causes the mechanistic approach of composite modeling in the well-established composite theory difficult to be applied, since modeling the contribution of natural fibers to the performance of thermoplastic composites is not as straightforward like in the case of homogenous glass fiber (with same shape, diameter and narrow length distribution). Alternatively, a statistical approach of modeling by using designed experiments was used in this research. The Mixture and Process-Mixture Experimental Design methodologies were applied to develop response surface models that can be used to correlate input properties and formulation of these thermoplastic composites to the final properties of the product. The models obtained can then be inverted to predict the required properties and formulations using fiber (straw), matrix (polypropylene), and additives (coupling agent) as the main components for a specified product performance. The prediction includes the fiber grading (size and aspect ratio) and classification in order to maximize fiber utilization for different needs of composite products. The experiments were designed based on the analysis of the existing data provided by previous research works of wheat straw polypropylene composite system in our laboratory and by experimental data generated during this research. The focus of the analysis was the determination of the factor(s), i.e., the independent variables of the experiments and their acceptable levels. The response variables being measured were chosen based on the required specifications of targeted products. A constrained three-component mixture design of experiment was conducted to develop models for flexural properties of WS-PP composite. The three independent mixture variables in this experiment were the weight proportions of: straw (as fiber), polypropylene (as matrix), and maleic anhydride polypropylene (as coupling agent). Statistical analysis results showed that the obtained models have met standard requirements of response surface models with good predictive capability. One of the important finding of this study was the formulation for optimum coupling agent proportion which gives the best flexural properties of composite. The effect of straw fiber size on composite properties was investigated by using fiber length and aspect ratio as parameters to describe fiber size, instead of the size of sieves used in fiber preparation. Two-stage separation method was applied in the straw fiber preparation process. In this method, width-based separation was followed by length-based separation to obtain fiber fractions with distinct fiber length and aspect ratio. Samples of thermoplastic composites for measurement of physical properties were produced from each fiber factions at two different levels of fiber loading. The samples were compounded by twin-screw extrusion and specimens were prepared by injection molding. The fibers were then extracted from the samples after injection molding (using solvent) and their sizes were measured to investigate the fiber size reduction during the compounding and molding process. A comprehensive analysis was then performed to study the responses of stiffness, impact resistance and specific properties of these composites by including initial fiber sizes, fiber chemical compositions (measured as cellulose, hemi-cellulose and lignin), fiber size reduction during compounding/molding process, and fiber loading as factors. One of the important contributions of this study is fiber grading in terms of their sizes and their respective contributions to the final composite product properties. Based on the previous results, a mixture design of experiment was performed on wheat straw – polypropylene / impact copolymer polypropylene (WS-PP/ICP) composite system. The objective of the experiment was to obtain response surface models that can be used to estimate some important properties required by a set of automotive product specifications. The optimum formulation of coupling agent obtained in the previous study was used to determine the fixed recipe of coupling agent; simplifying the composite system into a three-component mixture, i.e. straw (as fiber) and polypropylene (homopolymer and impact copolymer (polypropylene blend as matrix). Simulation of the models shows the superiority of using a blend of polypropylenes to balance the stiffness and impact strength of the composites and being able to reach three targeted product specifications. A case study was also performed to demonstrate that the models can be used to find optimum formulations to minimize material cost while meeting specifications of all targeted products. Finally, a framework for wheat straw polypropylene product design and development is presented in this thesis. The framework can be used for designing polypropylene-straw thermoplastic composites with various combinations of fiber - polymer matrix - additive systems with different product attributes and specifications suitable for several applications in the automotive industry.
84

How Simple Product Design Affects Consumer Responses

CHANG, CHIA-CHIEH 31 January 2012 (has links)
Product design affects many aspects of people¡¦s life. This research use qualitative and quantitative methods, and focus on how simple design cause different consumer responses. First of all, we process a content analysis aiming for household and digital product, and then we conduct the definition and characteristics of simple design. Second, we use experimental design to figure out the pattern of consumer responses to product design both psychological and physical. For psychological responses, we observe the consumer expectation and satisfaction in product appearance, assortment size and functional information; we also exam the different decision making tendency (Maximizer & Satisficer) in consumer approach behavior. According to our research, we conclude that the required elements of simple design are (1) Single Color, (2) Unique Personality, (3) Simple Shapes, (4) Practical Function, (5) Easy to Use, (6) Match, (7) Materials, (8) Aesthetics and (9) Culture & Emotion. For product external appearance, there is high expectation for simple design, and also satisfaction still has a big room to improve. To be more specific, in the aspects of attention drawing, unique symbol and ergonomic is the biggest gap between expectation and satisfaction. In the part of assortment size, simple design causes a higher expectation when the size is large. However, satisfaction did not drop as previous studies suggested, it remains indifferent which could be the suggestion for future product development. In function information, it plays a important role in digital product which means mainly simple designed appearance can only achieve limited benefits. In behavioral response, satisfaction and approach behavior have positive relation, and the responses of store are apparently stronger than the responses of single product. In different decision making tendency, product personality, attention drawing and assortment size are significant, but there is no clear result for function information.
85

Investigating the innovation capabilities of undergraduate engineering students

Williams, Paul T 19 November 2013 (has links)
This thesis describes a method for measuring the innovation capabilities of mechanical engineering students and presents the results of a yearlong experiment. A review of relevant literature shows that it is unclear whether the innovation capabilities of engineering students increase or decrease over time. Experiments were conducted at two universities in which students were asked to redesign an everyday electromechanical product in a sketch-based concept generation activity. Student participants were also asked to complete a self-efficacy survey. Nearly one thousand concepts were generated from a combination of freshmen and seniors. The concepts were evaluated for originality, technical feasibility, and innovation characteristics by multiple raters. At both schools, the findings suggest that the senior-level engineering students are more creative than their freshman-level counterparts without sacrificing technical feasibility. Additionally, the seniors rated higher for originality at the end of the semester than they scored prior to taking their senior design class. These results suggest that the mechanical engineering curricula, and especially the senior-level Engineering Design courses, are having a positive effect on student creativity. / text
86

Foundations of a reverse engineering methodology

Guillory, Jeremy Barrett 17 June 2011 (has links)
Reverse engineering is broadly defined as the process of analyzing existing products to learn how to create better products in the future. Including reverse engineering as part of the engineering design process can provide a number of benefits, including a more thorough understanding of existing products, lower cost for the redesign of products, and faster times to market. While reverse engineering can be applied to a wide range of domains, this thesis deals with methodologies for extracting technical data from electro-mechanical products for the purpose of recreating them functionally and dimensionally, to an acceptable level of accuracy. An integrated and evolved reverse engineering methodology is presented. This new methodology is built upon previous work, and results from an effort to integrate all previous methods into the simplest and most useful form. Five novel reverse engineering techniques are introduced to solve problems previously unaddressed in the literature: Bounding Pertinent Geometry, Reassembly by Function, Determining Sample Size, Estimating Production Volume and Accounting for Physical Degradation. Throughout the thesis, a running example of the reverse engineering of the Craftsman Auto Hammer is used to illustrate the application of the evolved methodology. / text
87

Beleaf : an earth-friendly solution to disposable dinnerware

Adhikary, Amrita Prasad 18 July 2011 (has links)
This report is a documentation of an investigative design process that looks at how small shifts in established systems can be reconfigured to make big changes. It is an attempt at establishing a framework for designing sustainable solutions with the environment and social good in mind. In addressing the problems resulting from our indiscriminate use of plastic disposable dinnerware and offering a viable and earth-friendly system solution to the same, I am interested in reminding fellow designers that accountability towards the environment is the new design reality. The report advocates methods that synthesize design for people, profit, and most importantly, the planet. By using plates made from fallen leaves, the user fulfills his specific need for disposable dinnerware while simultaneously participating in an environmental task of closing the loop through responsible disposal and composting. / text
88

Visual aesthetics in product development : A balance between commercial and creative imperatives

Lindahl, Ingela January 2013 (has links)
The literature presents a number of advantages regarding companies’ strategic focus on product design, arguing that the dimension of visual aesthetics in products may help a company to create commercial success, e.g. through product differentiation and as a means of company brand recognition. However, developing new products that have visual aesthetics as an important dimension is not without difficulty, and may lead to a number of managerial challenges. The purpose of this doctoral thesis is to describe and analyse how companies develop products that have visual aesthetics as an important dimension. The thesis describes and analyses: how the dimension of visual aesthetics affects the characteristics of the new product development process; how companies strike a balance between commercial and creative imperatives during new product development; and how companies source and collaborate using artistic design resources during new product development. Based on findings from five new product development projects and from interviews with managers at twelve Swedish designer furniture manufacturers, the thesis concludes that the dimension of visual aesthetics in products affects new product development in different ways. First, companies’ development of visual aesthetics calls for a more creative, artistic development process whereby, for example, idea generation and evaluation are often flexible in relation to plans made. Moreover, the different and subjective judgement of the aesthetic value of products has implications for new product development, e.g. that the company needs to address and balance imperatives stemming from different audiences, i.e. the designer’s self, peers, and the mass market, during product development. Also, it is concluded that the sourcing of designer resources and the composition of designer portfolios are both critical and related to companies’ desired brand image. A close and trustful working relationship between the designer and the manufacturer is a basis for companies’ successful product development. Theoretically, this research contributes to the product development literature through its findings on companies’ new product development processes in a seldom researched context, i.e. the development of designer products. Additionally, it contributes to the literature on design outsourcing by presenting new findings on the interplay between artistic design resources and managers. Moreover, it also contributes to the marketing literature by providing fresh insights into how companies balance their commercial and creative interests when developing new products. / Design och dess relation till företags marknadsföring är något som diskuteras både i akademisk litteratur och i samhället i övrigt. Genom att förstå och utnyttja design kan företaget skapa kommersiella fördelar, t ex genom att differentiera produkten från konkurrenternas och skapa igenkänning för företagets varumärke. Dock är utveckling av produkter med design som en viktig dimension inte oproblematisk utan kan leda till stora utmaningar för företaget. Tre sådana utmaningar i företag beskrivs och analyseras i denna avhandling. För det första behandlar avhandlingen hur ett fokus på design påverkar företagets produktutvecklingsprocess. Vidare studeras hur företaget balanserar kreativa och kommersiella intressen under produktutvecklingsprocessen. Dessutom behandlar avhandlingen hur företaget införskaffar och samarbetar med formgivare. Den industriella kontext som valts för denna avhandling är den svenska designmöbelindustrin. Avhandlingens slutsatser bygger på fallstudier inom väletablerade och framgångsrika företag inom denna industri. Avhandlingen visar att dimensionen av design påverkar företagens utvecklingsarbete på olika sätt. Först visar studien att de studerade företagens utveckling av designmöbler innebär en kreativ utvecklingsprocess där t.ex. idé-generering och ‑urval sällan grundas i strikta produktplaner utan i stället präglas av flexibilitet och tillvaratagande på uppkomna möjligheter. Vidare är bedömningen av en produkts designvärde subjektiv och svår att formulera i ord. Urvalet av lovande produktidéer grundas därför i hög grad på ledningens goda kunskap om design och erfarenhet inom branschen. Utöver detta påverkas företagens produktutveckling på olika sätt av det faktum att designvärde också skapas genom uppmärksamhet och uppskattning av exempelvis press, mässor och utmärkelser. Det visas också att företagens urval av formgivare är kritiskt och basen för ett framgångsrikt utvecklingsarbete. I de studerade företagen sker utveckling av produkter i nära och förtroendefullt samarbete mellan managers och formgivare. Dessutom kan företag påverka sitt varumärke genom att skapa en genomtänkt strategi för urval av formgivare och samarbetsformer med dessa.
89

The application of phase change materials to cool buildings

Susman, Gideon January 2012 (has links)
Five projects improve understanding of how to use PCM to reduce building cooling energy. Firstly, a post-installation energy-audit of an active cooling system with PCM tank revealed an energy cost of 10.6% of total cooling energy, as compared to an identical tankless system, because PCM under%cooling prevented heat rejection at night. Secondly, development of a new taxonomy for PCM cooling systems allowed reclassification of all systems and identified under-exploited types. Novel concept designs were generated that employ movable PCM units and insulation. Thirdly, aspects of the generated designs were tested in a passive PCM sail design, installed in an occupied office. Radiant heat transfer, external heat discharge and narrow phase transition zone all improved performance. Fourthly, passive PCM product tests were conducted in a 4.2 m3 thermal test cell in which two types of ceiling tile, with 50 and 70% microencapsulated PCM content, and paraffin/copolymer composite wallboards yielded peak temperature reductions of 3.8, 4.4 and 5.2 °C, respectively, and peak temperature reductions per unit PCM mass of 0.28, 0.34 and 0.14 °C/kg, respectively. Heat discharge of RACUS tiles was more effective due to their non-integration into the building fabric. Conclusions of preceding chapters informed the design of a new system composed of an array of finned aluminium tubes, containing paraffin (melt temperature 19.79 °C, latent heat 159.75 kJ/kg) located below the ceiling. Passive cooling and heat discharge is prioritised but a chilled water loop ensures temperature control on hotter days (water circulated at 13 °C) and heat discharge on hotter nights (water circulated at 10 °C). Test cell results showed similar passive performance to the ceiling tiles and wallboards, effective active temperature control (constant 24.6˚C air temperature) and successful passive and active heat discharge. A dynamic heat balance model with an IES% generated UK office’s annual cooling load and PCM temperature%enthalpy functions predicted annual energy savings of 34%.
90

DFMA : A Methodology Study and Method Development / DFMA : En Metodikstudie och Metodutveckling

Torkelsson, Olle, Dauksz, Markus January 2014 (has links)
Volvo Cars Corporation (VCC) is devoted to Lean and Six Sigma, and has lately considered an imple-mentation of Design for Manufacturing and Assembly (DFMA) with the purpose of improving their product design process and production. The goal for this project work is therefore to investigate if DFMA is a beneficial method for VCC to use, how DFMA can be used and suggest a DFMA method. A literature study is performed as a starting point to understand DFMA methods and its possibilities. Scientific articles, technical books and online sources is used during the study in order to gather in-formation regarding DFMA implementations, application areas, approaches and potential risks that need to be eliminated for a successful implementation. In order to map the product development and manufacturing processes of VCC interviews are per-formed. The interviews also gathered information regarding what VCC employees thinks of DFMA and how they wish to use it. This information is compiled into a demand specification where the de-mands are weighted after importance by the interviewees. After the pre-study, three idea generation sessions is performed with three different focus groups. The generated ideas are then evaluated and classified. The remaining ideas are classified with the purpose of enabling the possibility to use a morphological chart to build whole concepts from the single ideas. Three concepts are chosen amongst the generated concepts. These concepts are then evaluated against the weighted demand specification. The concept considered most suitable is further devel-oped which resulted in a proposed DFMA method for VCC. A case study on a product is performed in order to communicate, test and evaluate the final DFMA method. The project is rounded off with discussions regarding DFMA and the suggested method from sustain-ability point of view and how to motivate usage. All results and discussions from the project are handed over to the company, enabling further research on a possible implementation of DFMA in the organization. / Volvo Cars Corporation arbetar hängivet efter metoderna Lean och Sex Sigma och har avsikt att im-plementera Design for Manufacturing and Assembly (DFMA) i syfte att förbättra deras produkt- och produktutvecklingsprocess. Målet med detta arbete är att undersöka om DFMA är en värdefull me-tod för VCC att använda och hur metoden kan tänkas användas och implementeras inom organisat-ionen. Som utgångspunkt för att förstå DFMA metoden och dess möjligheter genomförs en litteraturstudie. Under studien granskades aktuella vetenskapliga artiklar, tekniska böcker och webbkällor i syfte att samla information om DFMA-implementeringar, användningsområden, tillvägagångsätt och potenti-ella risker som behövs elimineras för en lyckad implementation av metoden. Vidare utförs intervjuer i syfte att kartlägga produktutvecklings- och tillverkningsprocessen samt samla information om hur anställda ställer sig till, och önskar använda DFMA. Denna information sammanställs sedan till en kravspecifikation där kraven i sin tur viktas av intervjuobjekten efter hur viktiga de anses vara. Tre idégenereringssessioner utförs därefter med tre olika fokusgrupper. Dessa idéer gallras sedan ut och klassificeras för att sedan kombineras med hjälp av en morfologisk tabell i syfte att bygga kon-cept av de enskilda idéerna. Tre koncept väljs ut bland de genererade koncepten. Dessa koncept utvärderas sedan mot varandra med kravspecifikationen som bedömningsskala. Det koncept som bedöms som mest lämpligt vidare-utvecklas och en föreslagen metod för VCC tas fram. För att testa och illustrera den slutgiltiga meto-den genomförs en fallstudie på en produkt. Arbetet rundas av med diskussioner kring DFMA och den föreslagna metoden ur både hållbarhets-synpunkt och motivationssynpunkt. Samtliga resultat och diskussioner överlämnas sedan till företa-get för att möjliggöra vidare undersökningar kring en eventuell implementation av DFMA. / DFMA FMEA DFM DFA Lean Produktdesign Metodutveckling

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