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  • 51.
    Bergseth, Ellen
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Torbacke, M.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Tribologi.
    Wear in environmentally adapted lubricants with AW/EP technology2008In: Tech. Akad. Esslingen Int. Tribol. Colloq. Proc., 2008Conference paper (Refereed)
    Abstract [en]

    Mineral oil based lubricants are dominating the market still. However, there is now a broad range of environmentally adapted lubricants (EAL) based on both natural and synthetic esters. Wear was studied in a pin-on-disc-machine giving the wear coefficient. The surface reactions formed by the additives were examined. The studied lubricants were formulated with a complex ester as the base fluid. The wear number decreased with increasing reacted surface layer depth as well as with increasing oxide layer. A highly polar base fluid gave relatively low wear numbers even without additives. This is an abstract of a paper presented at the 16th International Colloquium Tribology Lubricants Materials and Lubrication Engineering (Stuttgart/Ostfildern, Germany 1/15-17/2008).

  • 52.
    Bergseth, Ellen
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Zhu, Yi
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Study of surface roughness and surface orientation onfriction in rolling/sliding contacts: barrel-on-disc versustwin-discManuscript (preprint) (Other academic)
  • 53.
    Börjesson, Fredrik
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    A Systematic Qualitative Comparison of Five Approaches to Modularity2010In: International Design Conference: Design 2010, 2010, p. 147-156Conference paper (Refereed)
    Abstract [en]

    An approach to modularity is used to mean the method by which a modular architecture is defined. This paper presents a method by which such approaches can be compared, incorporating both academic and experience-based criteria. The proposed method, based on dendrograms, is applied on MFD, Component-based DSM, Heuristics, and two derived approaches. Derived approaches seem to offer improvements, but also introduce new disadvantages which are absent in the methods on which they build.

  • 54.
    Börjesson, Fredrik
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Approaches to Modularity in Product Architecture2012Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Modular product architecture is characterized by the existence of standardized interfaces between the physical building blocks. A module is a collection of technical solutions that perform a function, with interfaces selected for company-specific strategic reasons. Approaches to modularity are the structured methods by which modular product architectures are derived. The approaches include Modular Function Deployment (MFD), Design Structure Matrix (DSM), Function Structure Heuristics and many other, including hybrids. The thesis includes a survey of relevant theory and a discussion of four challenges in product architecture research, detailed in the appended papers.

    One common experience from project work is structured methods such as DSM or MFD often do not yield fully conclusive results. This is usually because the algorithms used to generate modules do not have enough relevant data. Thus, we ask whether it is possible to introduce new data to make the output more conclusive. A case study is used to answer this question. The analysis indicates that with additional properties to capture product geometry, and flow of matter, energy, or information, the output is more conclusive.

    If product development projects even have an architecture definition phase, very little time is spent actually selecting the most suitable tool. Several academic models are available, but they use incompatible criteria, and do not capture experience-based or subjective criteria we may wish to include. The research question is whether we can define selection criteria objectively using academic models and experience-based criteria. The author gathers criteria from three academic models, adds experience criteria, performs a pairwise comparison of all available criteria and applies a hierarchical cluster analysis, with subsequent interpretation. The resulting evaluation model is tested on five approaches to modularity. Several conclusions are discussed. One is that of the five approaches studied, MFD and DSM have the most complementary sets of strengths and weaknesses, and that hybrids between these two fundamental approaches would be particularly interesting.

    The majority of all product development tries to improve existing products. A common criticism against all structured approaches to modularity is they work best for existing products. Is this perhaps a misconception? We ask whether MFD and DSM can be used on novel product types at an early phase of product development. MFD and DSM are applied to the hybrid drive train of a Forwarder. The output of the selected approaches is compared and reconciled, indicating that conclusions about a suitable modular architecture can be derived, even when many technical solutions are unknown. Among several conclusions, one is the electronic inverter must support several operating modes that depend on high-level properties of the drive train itself (such as whether regeneration is used). A modular structure for the electronic inverter is proposed.

    Module generation in MFD is usually done with Hierarchical Cluster Analysis (HCA), where the results are presented in the form of a Dendrogram. Statistical software can generate a Dendrogram in a matter of seconds. For DSM, the situation is different. Most available algorithms require a fair amount of processing time. One popular algorithm, the Idicula-Gutierrez-Thebeau Algorithm (IGTA), requires a total time of a few hours for a problem of medium complexity (about 60 components). The research question is whether IGTA can be improved to execute faster, while maintaining or improving quality of output. Two algorithmic changes together reduce execution time required by a factor of seven to eight in the trials, and improve quality of output by about 15 percent.

  • 55.
    Börjesson, Fredrik
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Improved Output in Modular Function Deployment Using Heuristics2009In: Proceedings of the 17th International Conference on Engineering Design (ICED’09), Vol. 4, 2009, p. 1-12Conference paper (Refereed)
    Abstract [en]

    In Modular Function Deployment, technical solutions are grouped into modules according tothe product properties and the strategic intentions of the company. Statistical methods such ashierarchical clustering are useful in the formation of potential modules, but a significantamount of manual adjustment and application of engineering common sense is generallynecessary. We propose a method for promoting better output from the clustering algorithmused in the conceptual module generation phase by adding Convergence Properties, acollective reference to data identified as option properties, geometrical information, flowheuristics, and module driver compatibility. The method was tested in a case study based on acordless handheld vacuum cleaner.

  • 56.
    Börjesson, Fredrik
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Product Platform Design: architecting methods and tools2014Doctoral thesis, monograph (Other academic)
  • 57.
    Börjesson, Fredrik
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Hölttä-Otto, Katja
    Improved Clustering Algorithm for Design Structure Matrix2012In: Proceedings of the ASME 2012 International Design EngineeringTechnical Conferences & Computers and Information in Engineering Conference, 2012Conference paper (Refereed)
    Abstract [en]

    For clustering a large Design Structure Matrix (DSM), computerized algorithms are necessary. A common algorithm by Thebeau uses stochastic hill-climbing to avoid local optima. The output of the algorithm is stochastic, and to be certain a very good clustering solution has been obtained, it may be necessary to run the algorithm thousands of times. To make this feasible in practice, the algorithm must be computationally efficient. Two algorithmic improvements are presented. Together they improve the quality of the results obtained and increase speed by a factor of seven to eight for normal clustering problems. The proposed new algorithm is applied to a cordless handheld vacuum cleaner.

  • 58.
    Börjesson, Fredrik
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.). odular Management USA, Inc., Bloomington, MN, United States .
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Modularization of novel machines: motives, means and opportunities2010In: Proceedings of NordDesign 2010, the 8th International NordDesign Conference: Chalmers University of Technology,Gothenburg, Sweden, August 25-27, 2010, 2010, p. 435-444Conference paper (Refereed)
    Abstract [en]

    Modularization approaches are often used to restructure mature products with known technical content, but not to assist new development of products with a high innovation content or soft interactive requirements. This paper investigates if various clustering techniques can be used to identify module candidates in matrix representations of evolving product properties, including interactive properties, and component architectures. The proposed approach is tested on the hybrid drive train of a novel forwarder. Forwarders are used in the forestry industry to transport logs from the felling area to a landing area close to a road accessible by trucks. Continuous efficiency improvements, new emission requirements, and the need to configure machine for different applications stresses the need for a modular product architecture.

  • 59.
    Cha, Matthew
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Dynamic Performance and Design Aspects of Compliant Fluid Film Bearings2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Due to government regulations together with health and safety reasons, there are increasing demands on reducing hazardous polluting chemicals from fossil fuel power plants. Therefore, more efforts are imposed on using renewable resources such as water, wind, solar and tide to produce clean/green electricity. On top of that, there is another increasing demand from Original Equipment Manufacturers (OEMs) to operate power plants with higher load while keep the power loss to the minimum. These requirements drive conventional fluid film bearings to its mechanical and temperature limits. This calls for the development of new bearing system designs. An outstanding tribological performance such as low start-up and break-away friction, excellent resistance to chemical attack and anti-seizure properties, can be achieved by introducing compliant polymer liners. At the same time, bearings with compliant liners may alter rotor-bearing system dynamic behaviour compared to the systems with conventional white metal bearings. The research approach of this thesis is to implement compliant liner on bearing surface, impose synchronous shaft excitation and investigate the effect of bearing design parameters on bearing dynamic response.

    Plain cylindrical journal bearings with different compliant liner thicknesses were analysed using a FEM approach. The numerical model was compared with an in-house developed code based on the finite difference method (FDM) for a bearing operated at steady state conditions. Results obtained by the numerical models showed good agreement. After verification of the numerical model for fixed geometry journal bearings, models for tilting pad journal bearings were developed. Dynamic behaviour of the tilting pad journal bearing with three pads with line pivot geometry was compared with published data. A good agreement was obtained between the two numerical models. The effect of pad pivot geometry on bearing dynamic response was investigated. Vertical and horizontal shaft configurations were compared in terms of the effect of preload factor, radial clearance, pivot offset, and pad inclination angles. Influence of the elastic properties of compliant liners was also studied. All these factors significantly affect bearing dynamic response. It is shown how these factors should be selected to control the journal orbit sizes. Misalignments in compliant tilting pad journal bearings were analysed for load between pivots and load on pivots with consideration of thermal effects. Significant improvements in bearing performance were obtained with compliant bearings compared to white metal bearings. Furthermore, different polymer materials (PTFE, UHMWPE, pure PEEK and PEEK composite) were characterized using Frequency Response Function (FRF). It was shown that as the excitation frequency increased the equivalent stiffness was more or less constant while equivalent damping decreased exponentially. PTFE had similar equivalent stiffness compared to PEEK. As for equivalent damping, PTFE had slightly higher damping compared to PEEK or UHMWPE. Oil film thickness, oil film temperature and loads on tilting pad journal bearing were measured on 10 MW Kaplan hydroelectric power machine. Test results were compared to FEM model. It was shown that stiffness of the supporting structure may be more important to machine performance than the stiffness of the bearing alone.

  • 60.
    Darvish, Parviz
    et al.
    ESSEC Business School.
    Abbasi, Saeed
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements. KTH, School of Engineering Sciences (SCI), Centres, The KTH Railway Group.
    Risk Hedging Optimal Capacity in the European Hub-based Natural Gas Market Network: A Model-based ApproachArticle in journal (Refereed)
  • 61.
    Ehrnberger, Karin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Räsänen, Minna
    School of Computer Science and Communication (CSC), Centres, KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC.
    Ilstedt, Sara
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements. KTH, School of Computer Science and Communication (CSC), Media Technology and Interaction Design, MID. School of Computer Science and Communication (CSC), Centres, KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC, Green Leap.
    Visualising gender norms in design: Meet the Mega Hurricane Mixer and the drill Dolphia2012In: International Journal of Design, ISSN 1991-3761, E-ISSN 1994-036X, Vol. 6, no 3, p. 85-94Article in journal (Refereed)
    Abstract [en]

    This article highlights how a gender perspective can be performed by design as critical practice. Two common household appliances - a drill and a hand blender - were used as a starting point. Inspired by Derrida's term deconstruction, the product language of the tools was analysed and then switched in two new prototypes: the hand blender Mega Hurricane Mixer and the drill Dolphia. The prototypes were shown at exhibitions and lectures. The comments by the audience show that a switching of product language entails that their relationship to the artifact itself also changes. Overall, the elements, which previously had been perceived as 'lacking transparency', were now visible. For example, the drill was identified as a "drill for women" and considered inadequate for drilling, and the mixer revealed needs and functions that the traditional mixer did not satisfy. This implies that design should not only be seen as 'final products' but as a part of a social process that takes place between the user, the artifact and the norms of society. By switching the product languages it was possible to highlight how gender values are connected to each design and each artifact. This means that the design of the artifacts around us is not fixed, but can be renegotiated and situated in time, place, and context.

  • 62. Folkesson, A
    et al.
    Gralén, KNorell Bergendahl, MargaretaKTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Integrated Product Development.Sellgren, Ulf LKTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Research for practice: Innovation in products, processes and organizations2003Conference proceedings (editor) (Refereed)
  • 63. Folkesson, A
    et al.
    Gralén, KNorell Bergendahl, MargaretaKTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Integrated Product Development.Sellgren, Ulf LKTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Research for practice: Innovation in products, processes and organizations.2003Conference proceedings (editor) (Refereed)
  • 64.
    Grimheden, Martin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Mechatronics.
    Ritzén, Sofia
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Integrated Product Development.
    Andersson, Sören
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Coaching Students into the Concept of Design Engineering2005In: Proceedings of the International conference on engineering design, ICED 05, Melbourne, Australia, 2005Conference paper (Refereed)
  • 65.
    Gustafsson, Mats
    et al.
    VTI - Swedish National Road and Transport Research Institute, Linköping, SE 581 95, Sweden.
    Abbasi, Saeed
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Blomqvist, Göran
    VTI - Swedish National Road and Transport Research Institute, Linköping, SE 581 95, Sweden.
    Gudmundsson, Anders
    Division of Ergonomics and Aerosol Technology, Lund University, SE 221 00, Lund, Sweden.
    Janhäll, Sara
    VTI - Swedish National Road and Transport Research Institute, Linköping, SE 581 95, Sweden.
    Johansson, Christian
    Department of Applied Environmental Science, Stockholm University, SE 106 91, Stockholm, Sweden.
    Norman, Micheal
    Stockholm Environment and Health Administration, SLB-analys, SE 104 20, Stockholm, Sweden.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Sjövall, Bill
    Stockholm Environment and Health Administration, SLB-analys, SE 104 20, Stockholm, Sweden.
    Wilhelmsson, H
    VTI - Swedish National Road and Transport Research Institute, Linköping, SE 581 95, Sweden.
    Particles in road and railroad tunnel air: properties, sources and abatement possibilities2013Conference paper (Refereed)
  • 66.
    Hedlund Åström, Anna
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Hotel Module in Glassfiber Sandwich: Environmental Study2008Report (Other academic)
    Abstract [en]

    In this report the structural material for a hotel module is qualitatively studied with focus onenvironment. The module is designed in composite sandwich material with cellular polymericfoam, Pet or PVC, covered by two glass fiber laminates on each side. This type of materialconstruction is traditionally used in transportation industry i.e. aerospace, aircraft, military shipsand yacht, demanding high stiffness in combination with low weight. But an increase in the usewithin the construction area can be seen especially within offshore industry were theenvironment is extremely corrosive.The investigated structure of a room and a bathroom includes floor, roof and three walls for eachmodule. A life cycle perspective, from cradle to grave (cradle) is used for the study starting withraw material production, product manufacturing, use of product and finally waste treatment indifferent forms. Parallel to the sandwich module building in conventional technique is includedfor comparison. This technique includes walls of wood joints with insulating material as mineralwool in between and then covered with gypsum wallboard. Joists are produced in concrete.As result environmental arguments are formed for the new sandwich alternatives and for theconventional technique. By just adding the arguments, for and against, turns out on favor for thePET sandwich module. For the material production the constituent materials for the sandwichgenerally presents higher CO2 emissions than the conventional building materials. But when itcomes to production and mounting of the module a number of arguments for the module can bestated. Better control of internal environment (working environment), efficient use of rawmaterial, effective transports. Compared to the conventional design the risk for problems withmoisture is non-existing for the sandwich structure.The best alternative for waste treatment of the sandwich module is reuse. Other alternative ismaterial recycling of glass fiber in combination with energy recovery for polyester and corematerial.For fire safety a recent full-scale test of a ship cabin point out the potential to design a fire safesandwich structure with appropriate insulating materials.

  • 67.
    Hedlund Åström, Anna
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Hotellmodul i glasfibersandwich: Miljöstudie2009Report (Other academic)
    Abstract [sv]

    I denna kvalitativa studie, analyseras en hotellmodul med fokus på miljöeffekter. Modulen byggs i sandwichteknik med täckskikt av glasfiberpolyesterkomposit och däremellan en kärna avcellplast av PET eller PVC. Denna typ av struktur används traditionellt inom transportindustrin tex. rymd, flyg och fartyg där hög styvhet i kombination med låg vikt krävs. Men en ökning avanvändandet av sandwich kan ses inom andra konstruktionsområden speciellt offshoreindustrindär miljön är extremt korrosiv. Den undersökta modulen omfattar, ett rum och badrum, golv, tak och tre väggar. Studien ärgenomförd utifrån ett livscykelperspektiv, från vaggan till graven (vaggan), med indelningen råmaterialtillverkning, produkttillverkning, användning av produkt och slutligen hantering av avfall i olika former. Parallellt med analysen av sandwichmodulen ingår även analys av konventionellt byggande, för jämförelse. Konventionellt byggande omfattar uppförande av väggar med träreglar och isoleringsmaterial som täcks med gipsskiva. Golv- och takbjälklaggjuts i betong.Som resultat formas miljöargument för de nya sandwichalternativen och den konventionella byggtekniken. Genom att studera argumenten, för och mot, genereras flest positiva argument försandwichmodulen med kärna av PET-cellplast. För tillverkning av material erhålls generellthögre CO2 utsläpp för de ingående materialen i sandwichmodulen än för konventionelltbyggande. Men för tillverkning av modulen och montering finns ett antal positive argument, bättre kontroll av inre miljö (arbetsmiljö), effektivt utnyttjande av råmaterial, och effektivatransporter. Jämfört med konventionellt byggande så är risken för uppkomst av fuktproblem små för modulstrukturen.Det bästa alternativet för avfallshantering av sandwichmodulen är återanvändning. Andra alternativ är materialåtervinning av glasfiber i kombination med energiutvinning av polyesteroch kärnmaterial. För studie av brandsäkerhet presenteras resultat från ett nyligen genomfört fullskaleförsök avbrand i en passagerarhytt på ett sandwichfartyg. Resultatet visar på möjligheten att med rätt brandisolering designa en sandwichstruktur med hög säkerhet mot brand.

  • 68.
    Hedlund Åström, Anna
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Life Cycle Cost Analysis of a Bus Structure2009Report (Other academic)
    Abstract [en]

    The importance of light weight materials are increasing especially for transporting applications as different types of vehicles. Though, the cost for production may increase due to higher material cost this can be beneficial in other parts of the product life cycle, especially the operation phase. By using light weight materials the structural weight decreases, which can be utilized either as reduced fuel consumption, increased payload, increased speed or increased range. This have been demonstrated in a number of projects especially concerning ship structures were both life cycle cost and environmental analysis has shown the benefits with light weight materials in composite sandwich structures and aluminium structures.

    In this study a bus structure originally manufactured in steel is investigated. The new lightweight structure is produced in sandwich technique with face in glass fibre polyester and different core materials, PET, PVC and PS depending on location in the structure. Life cycle cost analysis, LCCA, has been made to compare the steel structure with the sandwich structure. Included phases of the life cycle are production, operation and disposal.

    The result from the analysis results in a decrease of life cycle cost by 3 to 4% depending on the fuel price and the fuel consumption. The production cost for the sandwich structure is slightly higher, 4%, than the steel structure. This is explained by the higher material costs for the sandwich structure.

    By identifying the break-even point it is clearly shown that a decrease by two year, from year 4,5 to 6,5, is the result when doubling the fuel price, 1 €/litre to 2 €/litre. This is explained by the weight decrease of 5% for the total weight giving lower fuel consumption for the light weight structure by 5%.

  • 69.
    Hedlund Åström, Anna
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Life Cycle Cost Analysis of Ship Structures2008Report (Other academic)
  • 70.
    Hedlund Åström, Anna
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Life Cycle Cost and Environmental Analysis for Cruising Ship Superstructure2011Report (Other academic)
  • 71.
    Hedlund Åström, Anna
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Life Cycle Perspective for Light Weight Ship Structures in Terms of Cost and Environmental Effects2009In: International Conference on Light Weight Design for Marine Structures, 7-8 September 2009, Glasgow, U.K, 2009Conference paper (Refereed)
    Abstract [en]

    The importance of light weight material is increasing, especially for transport applications resulting in reduced fuel consumption. In the Swedish project LASS, Lightweight construction applications at sea, a number of different types of ships have been studied with emphasis to improve efficiency by reducing structural weight. One part of the project encompasses investigation of life cycle effects to demonstrate the environmental benefits and economic potentials when changing from traditional materials to lightweight materials. All included ship structures are analysed with life cycle cost analysis, LCCA and one of the structures is also investigated environmentally through life cycle assessment, LCA. In all cases the effectiveness in fuel economy is increased. For one of the ship structures, a high speed craft a weight saving around 40% results in decreased operation cost with 20% over 20 year of use. The weight savings can also be utilized as an increase in payload resulting in decreased energy consumption per transported payload. This is the case for a Ro-Ro ship investigated, resulting in a break-even after about 4 year when changing from steel to aluminium of the superstructure.

  • 72.
    Hedlund Åström, Anna
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Measurable indicators and matematical modelling: EU CargoXpress2009Report (Other academic)
  • 73.
    Hedlund Åström, Anna
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Waste Handling Alternatives for a Bus Structure  in FRP-Sandwich2009Report (Other academic)
    Abstract [en]

    Due to increasing environmental demands, especially on treatment of products end of life phase, product manufacturers and designers must consider the future disposal of their products. For conventional materials like steel and aluminium well organized methods for recycling exists. This is not yet the circumstances polymer composite materials, used more extensively, especially for transporting structures. Several techniques do exist but they are not yet commercially available. The current disposal methods of polymer composites are landfill and incineration.

    Here, disposal of a composite sandwich bus structure is studied, using an information model for assessing possible techniques for polymer composite material waste. This model is based on internal factors, which are related to the waste and to the processes. To implement the model relevant waste properties must be identified in order to fulfil the conditions set by the required processes involved.

    The result from using the information model shows that several methods are possible. Since three different core materials are used in the structure these must for some of the waste treatments be separated dependent on the use of the recycled material. For mechanical material recycling separation of the core material is recommended. Material recycling by cement manufacturing does not allow material containing PVC, which then must be separated. For several methods, the waste property CHEM, chemical composition, heat value and ash content must be analyzed. These methods are incineration with energy recovery, material recycling and energy/chemical recovery by fluidized bed or pyrolysis, material recycling by cement manufacturing and hydrolysis.

    A recommendation for design of the bus structure to facilitate the disposal treatment is to use the same type of core material through the structure and to decrease the use of PVC-core, since it needs specific consideration.

  • 74.
    Hedlund Åström, Anna
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Bazaz, Kushink
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Hou, Qianqian
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Forecast for future cost increases, material, labor and fuel: EU CargoXpress2011Report (Other academic)
  • 75.
    Hedlund Åström, Anna
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Luttropp, Conrad
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Access of hazardous and metallic integrated objects at dismantling of sandwich ship structures through effective information handling2006In: / [ed] Smit PK et al, ASRANet Ltd , 2006Conference paper (Refereed)
  • 76.
    Hedlund Åström, Anna
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Luttropp, Conrad
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Metal inserts and hazardous content in light weight composite structures in the context of recycling2006In: 13th CIRP International Conference on Life Cycle Engineering / [ed] Deflou, J. et al., 2006Conference paper (Refereed)
    Abstract [en]

    Polymer composite materials present many favourable properties. The low density results in high specific strength and stiffness, which makes these materials very interesting for applications within the transport field, including vehicles on land, at see and in air. Recently introduced legislation regarding waste treatment has put large demands on composite material producers and users. Although several methods exist they are not yet commercially available since composites is a rather new type of material. The waste treatment is complicated since composite materials consist of several materials, fibre, polymer matrix and additives. A model has therefore been proposed for assessing the different waste disposal techniques. The model focuses on the internal factors, which are defined as factors related directly to the waste and the processes of treatment in form of waste and process properties. In this paper two of these waste properties are identified as strategic for disposal of composite materials. These are the waste properties describing metal and hazardous content, MET and HAZ. To facilitate for future disposal two types of labels are suggested for these waste properties. The issue then is to decide the coordinates for how much information is needed and for whom. What, where and how?

  • 77.
    Hedlund Åström, Anna
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Luttropp, Conrad
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Reinoldsson, Per
    Industry.
    Environmentally friendly recycling of FRP-sandwich ship hulls2005Conference paper (Refereed)
    Abstract [en]

    Fibre composite material and sandwich structures are used more extensively especially for transporting structures, vehicles and vessels. This group of materials is young compared to the traditional metallic structural materials. Thus, experience for end of life treatment is missing for these new materials. Increasing environmental demands from customers and authorities forces the manufacturers to act.

    In this study a model for assessing possible disposal techniques is demonstrated for a sandwich hull from the Visby Class Corvette. The model is based on waste properties and conditions set by the processes involved in the different disposal techniques. Six different disposal techniques are investigated, from reuse to landfill. For the studied structure they are all possible to carry out.

    When considering external factors as market only two of them are possible today, energy recovery by waste incineration and landfill. According to the waste hierarchy set by the authorities for minimising environmental effects these methods are not on top of the list. Hopefully industrially techniques for material recycling will exists when this sandwich hull is actual for disposal.

  • 78.
    Hedlund-Åström, Anna
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Why Lightweight Ro-Pax?2008Conference paper (Refereed)
  • 79.
    Hedlund-Åström, Anna
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Björklund, Anna
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Umair, Shakila
    School of Computer Science and Communication (CSC), Centres, KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC.
    Life cycle cost and environmental effect analysis for a Ro-Pax superstructure in composite material2008Conference paper (Refereed)
  • 80.
    Hedlund-Åström, Anna
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Luttropp, Conrad
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Recycling of Composites: Guidelines based on Cost and Life Cycle Assessment2003Conference paper (Refereed)
  • 81.
    Hedlund-Åström, Anna
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Tasala Gradin, Katja
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Life Cycle Assessment and Life Cycle Cost Analysis of Innovative Vessel, The CargoXpress2015Conference paper (Other academic)
    Abstract [en]

    Alongside the economic growth demands for further use of resources increase as well. As a result of this transportation of industrial products all over the world will also increase, in particular through shipping. In this study a new innovative concept for transport of cargo, the CargoXpress vessel, is presented and analysed over the life cycle in terms of costs and environmental effects. In the life cycle cost analysis the influence of future price scenarios for LNG-fuel and structural material is investigated through sensitivity analysis. For the environmental study life cycle assessment is used according to ISO 14044:2006. In direct comparative analysis the environmental impacts and costs over the life cycle of the new vessel is compared to road transport by truck. Then also analysis is made by selecting different existing transport scenarios were the new vessel is compared to road transports. The results from both cost and environmental analysis clearly present benefits for transporting goods with the CargoXpress vessel. Regarding the cost several factors in combination plays an important role for the outcome as initial investment cost, price development of fuel and interest rate. For the environmental analysis the innovative vessel is shown to be the preferable alternative.

  • 82.
    Hedlund-Åström, Anna
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Tasala Gradin, Katja
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Bazaz, Kushink
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Bergström, Martin
    Center of Maritime Technologies e.V. , Hamburg.
    Life cycle cost and environmental assessment for the new competitive vessel2012Report (Other academic)
  • 83.
    Hedlund-Åström, Anna
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Tasala Gradin, Katja
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Bazaz, Kushink
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Bergström, Martin
    Center of Maritime Technologies e.V. , Hamburg.
    Results of competing transport scenarios road- transport versus maritime transport2012Report (Refereed)
  • 84.
    Hertzberg, Tommy
    et al.
    SP Sveriges Tekniska Forskningsinstitut.
    Hedlund Åström, Anna
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    The Composite Superstructure Concept: An Environment-Friendly & Cost Efficient Approach2010In: RINA, Royal Institution of Naval Architects - Ship Design and Operation for Environmental Sustainability - Papers, 2010, p. 17-25Conference paper (Refereed)
    Abstract [en]

    In 2003 the Swedish Governmental Agency for Innovation Systems, VINNOVA, made a call for research applications within the area of “Lightweight Materials and Lightweight Design”. The aim was to support a transition from high density construction materials to more sophisticated lightweight materials and to create networks of organisations (industry, research, authorities...) into a Technical Platform of various and complementary knowledge and know-how that could both support and sustain the said transition.The combination of a strong industrial interest and the need for fire safety design was the basis for SP Fire Technology to prepare and send an application to VINNOVA entitled “Lightweight construction applications at sea” (LASS). The core task described in the application was to investigate technically and economically four different vessels where appropriate parts had been re-designed using lightweight materials.The initial objects for study were:    A 24 m all composite passenger HSC (high speed craft)    An 88 m aluminium high speed catamaran with an FRP composite superstructure    A 199 m RoRo vessel with an aluminium deck house    A 188 m RoPax vessel with an FRP composite superstructure. Two additional objects were later introduced into the project:    An 89 meter dry cargo freight vessel with parts in FRP composite    An offshore living quarter (LQ) module in aluminium. The application was accepted by VINNOVA in the autumn of 2004 and the kick-off meeting was held in Borås in January 2005. The project officially ended the 30th of June, 2008.

  • 85.
    Häggström, Daniel
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Design (Div.).
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM).
    Björklund, Stefan
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements. KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Design (Div.).
    Evaluation of synchronizer loading parameters and their ability to predict failure2018In: Proceedings of the Institution of mechanical engineers. Part J, journal of engineering tribology, ISSN 1350-6501, E-ISSN 2041-305X, Vol. 232, no 9, p. 1093-1104Article in journal (Refereed)
    Abstract [en]

    Molybdenum coated gearbox synchronizers are tested in a mu-comp test rig under varying loading conditions until failure. Four different parameters used to describe the thermomechanical load are evaluated just before failure to compare their ability to predict failure. The parameters evaluated are the synchronized kinetic energy, the synchronization power, and the focal as well as the average surface temperature increase. The focal surface temperature increase as well as the average surface temperature increase is found to predict failure with relatively good accuracy. It is shown that there exists a threshold which divides the synchronizer into either a very long or a very short service life. Additionally, a method to determine the average surface temperature in the gearbox management system is proposed.

  • 86.
    Häggström, Daniel
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Design (Div.).
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM).
    Björklund, Stefan
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements. KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Tribologi. KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Design (Div.).
    The effect of manufacturing tolerances on the thermomechanical load of gearbox synchronizers2018Conference paper (Refereed)
    Abstract [en]

    Transmission performance is crucial for heavy trucks and connected vehicles in general and for platooning of trucks in particular. Gearbox synchronizers are highly loaded conical friction brakes used during gear shifts. Service life and, thus, the gear shifting reliability, of the synchronizer depend on the local thermomechanical loading of the contact surface. To achieve a robust and cost-efficient system, more knowledge is needed of how manufacturing tolerances affect the local thermomechanical loading and therefore service life and reliability of a synchronizer. The effects from angle deviations between the mating cones and cone out-of-roundness on focal maximum temperature during a synchronization sequence have been studied with transient thermomechanical simulations. It is shown that thermomechanical effects will significantly magnify the nominal effects on synchronization performance caused by shape deviations given by the specified manufacturing tolerances.

  • 87.
    Iwnicki, Simon
    et al.
    Manchester Metropolitan University.
    Björklund, Stefan
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Enblom, Roger
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Railway Technology.
    Wheel-rail contact mechanics2009In: Wheel-rail interface handbook / [ed] Roger Lewis, Ulf Olofsson, Cambridge, UK: Woodhead Publishing Ltd , 2009, p. 58-92Chapter in book (Refereed)
  • 88.
    Janhäll, Sara
    et al.
    VTI - Swedish National Road and Transport Research Institute, Linköping, SE 581 95, Sweden.
    Mats, Gustafsson
    VTI - Swedish National Road and Transport Research Institute, Linköping, SE 581 95, Sweden.
    Abbasi, Saeed
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Blomqvist, Göran
    VTI - Swedish National Road and Transport Research Institute, Linköping, SE 581 95, Sweden.
    Gudmundsson, Anders
    Division of Ergonomics and Aerosol Technology, Lund University, Lund, SE 221 00, Sweden.
    Johansson, Christian
    Department of Applied Environmental Science, Stockholm University, Stockholm, SE 106 91, Sweden.
    Norman, Michael
    Stockholm Environment and Health Administration, SLB-analysis, Stockholm, SE 104 20, Sweden.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Sjövall, Bill
    Stockholm Environment and Health Administration, SLB-analysis, Stockholm, SE 104 20, Sweden.
    Road tunnels - particle properties, wet and dry conditions2013Conference paper (Refereed)
  • 89. Jansson, Anders
    et al.
    Olander, Lars
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering (name changed to Building Service and Energy Systems 2012-03-01).
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Sundh, Jon
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Söderberg, Anders
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Wahlström, Jens
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).
    Ultrafine Particle Formation from Wear2010In: The International Journal of Ventilation, ISSN 1473-3315, E-ISSN 2044-4044, Vol. 9, no 1, p. 83-88Article in journal (Refereed)
    Abstract [en]

    Much attention is given to the consequences of airborne particles on human health and well-being. Wear is one source of airborne particles and contributions in the urban environments from wheel-to-rail contacts and disc brakes cannot be neglected. Traditionally, mechanical wear has been associated with the generation of particles of diameters of some microns. However, the research described has found ultrafine particle generation from wear processes. Particle generation from wear was measured under controlled laboratory conditions. The wear was created through sliding contact in a tribometer (type "pin-on-disc") with different materials and with different sliding velocities and pressures, to represent rail traffic and automobile disc braking. Particle concentrations and size distributions in the air were determined for particle diameters from 10 nm up to more than 10 mu m. For most materials and conditions three particle size modes were found: one at 50-100 nm, one at a few hundred nm and one at a few mu m particle diameter.

  • 90.
    Johannesson, Carl Michael
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    How to train and teach students in design at a technical faculty where science and applied technology is seen as prime knowledge: an example2012Conference paper (Other academic)
    Abstract [en]

    For nine years, the goal of the educational track Industrial Design Engineering (IDE) at KTH has been to prepare students for their future work as engineers, in product design or any other profession where their creative ability will be used. During their studies at IDE, we not only introduce students to their future as engineers but also prepare them for a global labour market, where companies shift from national ownership to international, where they might have to move between countries, even continents. We teach the essential technical courses but also train them in public speaking, writing, making decisions, setting priorities, dealing with meetings, and working with people from different disciplines. This approach also breeds new opportunities for the students. Whilst remaining a national educational track, the international appearance gives the IDE at KTH an individual character. What is the profile of the students applying for IDE? Can one assume that they are future designers? That is rarely their main intent, although most of the students have a common desire to express their creative abilities, to create new products and influence the future. The students' ability to communicate will deepen both in visual communication through sketching, physical modelling, computer modelling and in computer graphics. Each project involves training in presentation and report writing: Literature studies are written up as summaries; Field trips, international internship and minor field studies result in travel descriptions and weekly work reports. In the project's final presentations, the students exhibit skill in expressing themselves clearly, with a good balance between the spoken word, image and text. Project cooperation with businesses is a long-held tradition in this field of studies. In some cases, this can start as early as the bachelor thesis work, but usually begins in the fourth year in the advanced course projects as well as in collaborations with foreign universities for workshops, and in international internships. For many years IDE has had a cooperation with a Chinese manufacturer and to date ten groups of students have had the opportunity to work there as design engineers for a five-week period. In addition, a large number of the IDE students take the advantage of studying abroad on student exchange. The project courses and field trips are the result of an active collaboration with global and local manufacturers, brand organizations and universities. Visits to manufacturers constitute a unique and popular training method. Institutions and businesses contribute towards the costs of national travel and, where appropriate, subsistence. Thus the educational budget remains intact. We follow the students and feel relatively up to date on where they end up after their exams. We can venture to say that a combination of the IDE education and their own ability has given them good, interesting jobs in well-known large companies as well as in lesser-known but equally interesting companies. The majority go on to gain experience in any of the multinational Swedish companies such as Ericsson, Scania, Volvo, Kinnevik, IKEA, Electrolux, Alfa Laval, H&M, ABB, Vattenfall, Atlas Copco, and others. Many work in design companies or major engineering consultancies. Ultimately, the future looks bright for those graduating the IDE!

  • 91.
    Johansson, Jan
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Material Hygiene: An EcoDesign mindset for recycling of products2008Doctoral thesis, comprehensive summary (Other scientific)
    Abstract [en]

    In recent years the end-of-life phase has come into focus. European Union directives have been issued regulating certain product groups and producer responsibility. Vehicles and electronic products are the first to be identified and targeted. EU environmental legislation acts as a driver for increased reuse, recycling and recovery. The overall aim of the presented activities has been to increase the effectiveness of current recycling practices, both in terms of design changes and end-of-life treatment process suggestions. A “pre-step” operation has been suggested, in order to either salvage valuable (or toxic) material or to remove diluting bulk material. As this thesis is focused on the recycling of white-goods specifically dishwashers the suggested prestep would be removal of valuable copper prior to shredding. A life cycle assessment (LCA) study has been conducted. The purpose of this study was to determine if using a pre-step is beneficial from an environmental point of view or not. Furthermore, an experiment on the usability of recycled polymers from waste electrical and electronic equipment (WEEE) has been performed. Based on this work polymer recycling process suggestions are presented. Based on research in the fields of design for recycling, design for disassembly and EcoDesign the material hygiene (MH) concept of design for recycling is formulated. This concept is tested on a disassembly field study carried out at a waste collection facility and a polymer recycling experiment at a refrigerator fragmentation plant. Five MH factors are suggested: MH Mix, MH Identification, MH Resources, and MH Weight and MH Map. Additionally, a MH mind-set is presented.

  • 92.
    Johansson, Jan
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Luttropp, Conrad
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Material Hygiene: Improving recycling of WEEE demonstrated on dishwashers2009In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 17, no 1, p. 26-35Article in journal (Refereed)
    Abstract [en]

    There must be a change in attitude towards end-of-life products. The view that these products pose a liability must be changed. Secondary material is valuable as raw material. Thus, activities encouraging changes in opinion are important.

    Two major EU directives guide the recycling process; the Directive of End-of-Life Vehicles (ELV) and the Directive of Waste Electrical and Electronic Equipment (WEEE). Both focus on the input of the recycling system, not on what is coming out of the system.

    The WEEE Directive is the legislation on the European level that governs the handling and processing of these types of products. The WEEE Directive is not only aimed at stricter handling and reduction of hazardous materials but also encourages EU member states to support technical development in order to facilitate increased recycling.

    In order to properly address these issues a mind-set, material hygiene, has been introduced. The basic idea is to act, in every life cycle phase of the product, towards highest possible efficiency in recycling. The outcome of useful material is in focus.

    A study on dishwashers is made with copper outcome as target. The results are based on Swedish conditions but general conclusions can be made. Limited design efforts can raise the outcome of valuable materials, if the recycling process is organized in an optimal manner.

    A theoretical concept of disassembly structures is used to draw general conclusions on the case study. Increasing product recycling suitability is one side of the problem: another is increasing effectiveness of handling and processing of end-of-life products.

    The purpose of this paper is to introduce the concept of "material hygiene" and based on that demonstrate a method for grading structural properties in a recycling perspective. The findings presented in this paper are based on a field study in which a number of dishwashers were disassembled and analyzed.

  • 93.
    Johansson, Peter
    et al.
    Scania CV AB.
    Andersson, Sören
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Variations in piston second land pressure as a function of ring gap position2010In: International Journal of Engine Research, ISSN 1468-0874, E-ISSN 2041-3149, Vol. 11, no 2, p. 153-161Article in journal (Refereed)
    Abstract [en]

    The inter-ring pressure and the potential reverse blow-by flow that can drive oil towards the combustion chamber can strongly influence the in-cylinder oil consumption in diesel engines. This paper reports on an experimental investigation of the effect of both cycle-to-cycle variations and variations over a longer period on inter-ring pressure. The inter-ring pressure and piston ring movement were also simulated as a function of ring gap position. The experimental part of the project showed small cycle-to-cycle variations in the second land pressure as well as large variations over time. Simulations of the second land pressure with different ring gap positions showed a similar range of variation in second land pressure as the experimental variation.

  • 94.
    Karlsson, Reine
    et al.
    TEM Lund University.
    Luttropp, Conrad
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    EcoDesign: what's happening? An overview of the subject area of EcoDesign and of the papers in this special issue2006In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 14, no 15-16, p. 1291-1298Article in journal (Other academic)
    Abstract [en]

    EcoDesign is a concept including human sustainability priorities together with business interrelations. Its main objective in the improvementof product development methods is to reduce environmental loads. EcoDesign also includes a more open ambition to use inspiration from a widerfield of positive examples of smart products and methods, effective system solutions and attractive designs. It is not clear what sustainable productdevelopment is; what we can do is to try our best to find better solutions, get going and make sure that we learn from what happens. Our maingoal with this issue was to monitor ‘‘How to make it happen?’’ but we ended up with more questions and the lower ambition of, ‘‘What’s happening’’.Life-style elements such as brand label economy, development of new economies in Asia, aging populations in the old economies etc. makesthe picture even more complex and we still wonder, ‘‘How to make it happen’’. However, a few focal points can be observed:The tools in EcoDesign are not as important as specification and goal setting in early product development phases. How to organize productdevelopment is crucial in order to reach higher degrees of sustainability. The interrelations between resources and functionality must be enhanced.Environmental affection must be integrated into the human life-style and throughout the entire life-cycle of all products and services.To us it seems impossible to define a sustainable life-style and force everyone to follow. We must engage all stakeholders in envisioning andcreating the sustainable societies we hope to achieve.

  • 95.
    Khan, Suleman
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Mechatronics.
    Andersson, Kjell
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    A design Methodology for haptic devices2011In: Proceedings of the 18th International Conference on Engineering Design (ICED11), Vol. 4 / [ed] Culley, S.J.; Hicks, B.J.; McAloone, T.C.; Howard, T.J. & Lindemann, U., 2011, p. 288-298Conference paper (Refereed)
    Abstract [en]

    This paper presents a design methodology for optimal design of haptic devices, considering aspects form all involved engineering domains. The design methodology is based on parametric modeling, iterative and integrated design approach that leads to easier design space exploration for global optimal design and initial verification in the conceptual design phase. For global optimization, performance indices such as; workspace volume, isotropy, stiffness, inertia and control of the device were from all involved engineering domains were considered. To handle this complex and non-linear optimization problem, a multi-objective algorithm together with a new developed optimization function was used, to obtain a global optimum solution. A case study, where the methodology has been applied to develop a parallel haptic device is presented in detail in this paper. The results obtain from the test case model show significant improvements in the performances of the device.

  • 96.
    Khan, Suleman
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Mechatronics.
    Andersson, Kjell
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Wikander, Jan
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Mechatronics.
    Dynamic based control strategy for haptic devices2011In: World Haptics Conference (WHC), 2011 IEEE Issue Date: 21-24 June 2011 / [ed] IEEE, 2011, p. 131-136Conference paper (Refereed)
    Abstract [en]

    Transparency is a key performance measure for haptic devices. In this paper, we investigate a control strategy to increase the transparency of a haptic device. This control strategy is based on careful analysis of the dynamics of the haptic device, computed torque feed forward control and current feedback based force control. The inverse dynamic equation of motion for the device is derived using Lagrangian formalism and the dominating terms are identified for some representative motion trajectories. The user contact dynamic model is identified using experiments on the device with different users. A PI controller using motor current measurements is used to follow the reference force from the virtual environment. Experimental results illustrate the effectiveness of the control strategy.

  • 97.
    Khan, Suleman
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Mechatronics.
    Andersson, Kjell
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Wikander, Jan
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Mechatronics.
    Investigation of parallel kinematic mechanism structures for haptic devices2009In: 2nd Nordic Conference on Product Lifecycle Management – NordPLM’09, Gothenburg January 2009., 2009Conference paper (Refereed)
    Abstract [en]

    Today modeling and simulation tools like FE (Finite Element) and MBS (Multi Body Systems) simulation tools are commonly used within mechanical engineering. These types of tools offer capabilities of Virtual prototyping (VP) with the possibility to investigate and explore a product before a physical prototype is manufactured. This can reduce the number of physical prototypes needed and save both time and money. These tools are also well known to be an effective means to support the process of verification of formulated requirements. They can be used e.g. for evaluation and selection of alternative solutions or as a final check or optimisation of a solution concept. The use of these kinds of tools can be even more effective if an information framework for handling the information created during the verification process can support them.

    The outline of such an information framework has been presented by Andersson [1], [2], which support traceability and reuse of partial result created during the verification of a specific requirements attribute as well as a possibility to study the effects that changes in the requirements specification have on product properties. This type of framework need a fine granularity of information, to be able to reuse partial results e.g. component simulation models but also that the models are structured such that we can reuse them in new model configurations.

    This paper presents an investigation of 6-dof haptic devices based on parallel structure that can be used in a surgical training simulator for temporal bone milling or as a 6-dof input- output teleoperated haptic master device. This investigation follows the verification process outlined by Andersson [1], [2], where the haptic devices in this case the product concept to be evaluated. The basic idea behind these concepts is to develop a haptic device with a large workspace and high stiffness within this workspace based on modeling and analysis of two different concepts. The study will concentrate to find a way to measure performance parameters to be able to evaluate and compare different structures.

  • 98.
    Khan, Suleman
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Mechatronics.
    Andersson, Kjell
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Wikander, Jan
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Mechatronics.
    Optimal Design of a 6-DoF Haptic device2011In: Mechatronics (ICM), 2011 IEEE International Conference on, IEEE , 2011Conference paper (Refereed)
    Abstract [en]

    The work presented in this paper is motivated by the use of haptics in applications of medical simulation, particularly simulation of surgical procedures in hard tissue such as bone structures. In such a scenario haptic device characteristics such as stiffness, motions, suitable workspace and device footprint are key design factors. This paper presents a procedure for optimal design of a parallel kinematic structure for a 6-Dof haptic device. For optimization, performance indices such as workspace volume, kinematic isotropy and static actuator force requirements are defined. A specific Jacobian matrix normalization is introduced for defining the kinematic isotropy and actuator force requirement indices. For defining the optimization problem, a novel multi-criteria objective function is introduced. Based on this objective function, a genetic algorithm is used to solve the multi-objective and non-linear optimization problem. Also, sensitivity analysis of the performance indices against each design parameter is presented as a basis for selecting a final set of design parameters for prototype development. Finally, using these results, a prototype was implemented.

  • 99.
    Lagerstedt, Jessica
    et al.
    Bombardier Transportation, Mainline MLN/ESE Västerås.
    Luttropp, Conrad
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Guidelines in ecodesign: a case study from railway industry2006In: Innovation in Life Cycle Engineering and Sustainable Development / [ed] Brissaud, D; Tichkiewitch, S; Zwolinski, P, Springer Netherlands, 2006, p. 245-254Conference paper (Refereed)
    Abstract [en]

    Designers have a key role in adapting products to the environment and a sustainable society and many attempts have been made to establish universal DfE guidelines that can be used for these design situations. However, most attempts have failed due to the level of information; too generic makes no sense for the user, and too specific means that the guidelines are too private to be useful for everyone. Furthermore, designers and the acquisition department as well as marketing and production have different background knowledge and different primary tasks. Depending on the complexity and type of product as well as on the cultural background in-different companies and countries, the product development process looks different. It is therefore impossible to establish generic DfE guidelines that are valid for any product in any company. The 10 Golden Rules are a set of generic Design for Environment aspects (first presented by Luttropp (2000)). The "10 Golden Rules" are broad principles, which establish a common basis for a product development team, giving the team members a mutual perspective on the sustainability issue. The 10 Golden Rules are preferably individually customized to be of most use in direct design and product development process. This paper presents the customisation of the 10 Golden Rules at Bombardier Transportation, which is one of the worlds leading companies manufacturing rail vehicles.

  • 100. Lewis, R.
    et al.
    Magel, E.
    Wang, W. -J
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Lewis, S.
    Slatter, T.
    Beagles, A.
    Towards a standard approach for the wear testing of wheel and rail materials2017In: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 231, no 7, p. 760-774Article in journal (Refereed)
    Abstract [en]

    An examination of the literature for the wear testing methodologies for wheel and rail materials reveals that while only a few different techniques have been used, there is a wide variety in exactly how the tests have been conducted and the resulting data reported. This makes comparison of the data very difficult. This work, carried out as part of the International Collaborative Research Initiative which is aiming to bring together the wheel–rail interface researchers from across the world to collate data and knowledge to try to solve some of the common problems that are faced, has examined the different approaches used and has attempted to pull together all the good practice used into a test specification for future twin-disc testing for wheel and rail materials. The adoption of the method will allow data to be compared reliably and eventually enable data to be compiled into wear maps to use as input, for example, to multi-body dynamics simulation wear prediction tools.

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