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  • 1.
    Abdul Malek, Nurul Aida
    et al.
    Universiti Tun Hussein Onn Malaysia (UTHM), Malaysia / Department of Production, University of Vaasa, Finland.
    Shahzad, Khuram
    Department of Production, University of Vaasa, Finland.
    Takala, Josu
    Department of Production, University of Vaasa, Finland.
    Bojnec, Stefan
    Faculty of Management, University of Primorska, Slovenia.
    Papler, Drago
    Faculty of Management, University of Primorska, Slovenia.
    Liu, Yang
    Department of Production, University of Vaasa, Finland.
    Analyzing Sustainable Competitive Advantage: Strategically Managing Resource Allocations to Achieve Operational Competitiveness2015Ingår i: Management and Production Engineering Review, ISSN 2080-8208, E-ISSN 2082-1344, Vol. 6, nr 4, s. 70-86Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In today’s dynamic business environment, a key challenge for all companies is to make adaptive adjustments to their manufacturing strategy. This study demonstrates the competitive priorities of manufacturing strategy in hydro-power case company to evaluate the level of sustainable competitive advantage and also to further analyze how business strategies are aligned with manufacturing strategies. This research is based on new holistic analytical evaluation of manufacturing strategy index, sense and respond, and sustainable competitive advantage models. These models help to describe, evaluate, and optimize resource allocation to meet the performance requirements in dynamic decision making. Furthermore, these models evaluate operational competitiveness for manufacturing strategies according to the multi-criteria priority. The results show that the adjustments of competitive priorities in manufacturing strategies by implementing the proposed holistic analytical models are helpful in strategically managing business operations. The discussion derives the most critical attributes in business operations while alignment of resource allocation with competitive priorities help to strategically focus those attributes. In conclusion, we argue that resource allocation and manufacturing strategies have become the most important capabilities in a business environment where companies focus to get a sustainable competitive advantage.

  • 2.
    Abdullah, M Ailieen
    et al.
    Royal Institute of Technology.
    Öhrwall Rönnbäck, Anna
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell marknadsföring och industriell ekonomi. Linköpings universitet, Tekniska högskolan.
    Ölundh Sandström, Gunilla
    Royal Institute of Technology.
    Building Networks for Delivering Integrated Product-Service Offerings (IPSOs)2010Ingår i: Proceedings of 2nd CIRP IPS2 Conference 2010 - Industrial product-service systems -IPS², CIRP , 2010Konferensbidrag (Refereegranskat)
    Abstract [en]

    The paper describes the effect of forming business networks and collaborations for the purpose of developing an Integrated Product-Service Offering (IPSO) using the Product/Service Systems (PSS). The research method is an in-depth case study of a joint venture formed by four companies developing a new technology for chemical extraction from water sludge waste within the pulp and paper industry.

    Combining literature from PSS, network theories and collaborative product development, this paper puts forward the benefits for SMEs to collaborate in business networks and produce IPSOs when introducing a new technology in an emerging market. The case study shows that working towards the new market would not have been possible if each party acted individually or maintained their traditional buyer-supplieroperator roles, and that IPSOs can reduce the business risk.

  • 3.
    Abrahamsson, Mats
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Logistik. Linköpings universitet, Tekniska högskolan.
    Rehme, Jakob
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell marknadsföring och industriell ekonomi. Linköpings universitet, Tekniska högskolan.
    The Role of Logistics in Retailers' Corporate Strategy: A Driver for Growth and Customer Value2010Ingår i: Supply Chain Forum: an International Journal, ISSN 1625-8312, E-ISSN 1624-6039, Vol. 11, nr 4, s. 14-23Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This article explores the role of logistics and supply chain management (SCM) in retailers’ corporate strategy and is based on reviewing multiple qualitative case studies of companies in the Swedish food retail sector. The article proposes that the role of logistics for what is referred to in this paper as modern retailers is twofold: to create profitability and to support growth and market expansion. International modern retailers are empirically compared with similar companies in the Swedish market. The dominating Swedish food retailers have taken command in the food supply chain but are primarily concerned with traditional logistics roles in cost cutting. This role is perfectly fine as long as the strategic intent of the companies is focused on market retention and not on geographical expansion and/or new marketing or store concepts. We argue that the success of modern retailers in terms of growth rate, profitability, and market expansion is explained to a large extent by the role of logistics in corporate strategy—when the role for supporting growth and increasing customer value from high-performance supply capabilities is a driver for market expansion. However, in many of our cases the traditional logistics roles of cutting costs and lead-times is still the dominating pattern that limits the possibility of expanding into new markets. Better knowledge of logistics’ role in retail corporate strategy can help companies develop and improve their strategic intent as well as redefine the role of logistics.

  • 4.
    Achten, Peter A J
    et al.
    Innas BV, Breda, Netherlands.
    Vael, Georges E M
    Innas BV, Breda, Netherlands.
    Heybroek, Kim
    Volvo Construction Equipment, Eskilstuna, Sweden.
    Efficient hydraulic pumps, motors and transformers for hydraulic hybrid systems in mobile machinery2011Ingår i: VDI-Fachkonferenz Getriebe in Mobilen Arbeitsmaschinen, Düsseldorf: VDI-Wissensforum , 2011, s. 1-19Konferensbidrag (Refereegranskat)
    Abstract [en]

    A detailed simulation of a large 33 metric ton wheel loader, carrying out the short loading cycle, has been performed. Two systems have been compared and examined side by side:

    • The conventional system, having a mechanical transmission for driving the wheels and a conventional load sensing hydraulic circuit for the work and steering cylinders.
    • A new hydraulic hybrid system for the wheel drive and the implements, applying new and efficient hydrau- lic pumps and motors.The core of the new system is the hydraulic transformers which convert and control all the hydraulic power flows inside the loader.

    The new system results in a reduction of the fuel consumption of about 50% in the analyzed cycle. The new transmission and hydraulic system also results in a strong reduction of the cooler demands.

  • 5.
    Adebring, Carl Jonas
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling.
    Zachrisson, Fredrik
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling.
    Leverantörsrelationer på Volvo Aero Corporation: En modell för val av lämplig strategi för leverantörshantering2007Självständigt arbete på grundnivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats
    Abstract [sv]

    Volvo Aero Corporation är en stor leverantör till de tre stora flygmotortillverkarna, General Electric, Pratt & Whitney och Rolls Royce. Komponenter som företaget producerar används i över 80 % av dagens kommersiella motorer. Nya motorprogram, där Volvo Aero eftersträvar att ha en mer aktiv roll gällande design och utveckling, har lett till nya utmaningar för företaget. Samtidigt har en komplicerad leverantörsmarknad, bland annat på grund av konsolidering, blivit svårare att hantera. Av denna anledning finns ett intresse av att förbättra företagets relationer och samarbeten med sina leverantörer, bland annat för att höja effektiviteten och sänka kostnader och ledtider.

    I ett led att klara detta, gav Volvo Aero oss uppgiften att studera och analysera teorier kring hantering av leverantörsrelationer för att se om vi kunde hitta passande modeller som är applicerbara på de nya situationer som företaget står inför.

    Vi utförde studier av en mängd teorier, och sökte att finna vilka som passade Volvo Aeros situation bäst. Många av de teorier vi funnit har sitt ursprung i fordonsindustrin eller Lean produktion, men vi har även använt mer generella teorier. Vi identifierade från dessa teorier de parametrar som har inflytande på vilken typ av förhållande företaget bör ha. Vi sökte speciellt efter de nyckelparametrar som bestämmer förutsättningarna för relationen, exempelvis maktbalansen eller mängden anpassningar och investeringar som företagen gjort.

    Utifrån detta har vi skapat en modell bestående av de teorier vi funnit relevanta, där vi applicerar parametrar specifika för en given relation. Modellen ger sedan underlag för att dra slutsatser om vilka strategier som är lämpliga för relationen givet den förenklade verklighet som parametrarna beskriver.

    Vi applicerade denna modell på tre specifika fall, och gjorde dessutom en generell analys av företaget leverantörsrelationer. De specifika fallen utgjordes av leverantörsrelationer som vi valt ut tillsammans med Volvo Aero. I den generella analysen tvingades vi till ett mer abstrakt resonemang, men vi baserade även där analysen på de parametrar och teorier som utgjorde modellen.

    Vad vi fann med analysen var att modellen fungerade på önskat sätt, och att det var möjligt att applicera teorierna på företaget med till synes goda resultat. Vi kan från detta även dra slutsatsen att modellen är applicerbar även på andra leverantörsrelationer, så väl som på andra företag, men då eventuellt med mindre justeringar.

  • 6.
    Adolfsson, Fredrik
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling.
    Koning av båtmaster: Undersökning av möjligheter till effektivisering2008Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats
    Abstract [sv]

    Koning av båtmaster görs i dagsläget med höga kassations- och arbetskostnader. De huvudsakliga orsakerna är svåra inställningar och varierad efterfrågan, en annan orsak är att tillverkningen är hantverksmässig vilket ger lågt fixturutnyttjande.

    I takt med att nya masttyper börjat konas kommer arbetskostnaderna minska relativt intäkterna givet att de nya volymerna kan hanteras med nuvarande bemanning. Detta förutsätter högre produktivitet i fixturerna.

    För att anpassa koningen mot en högre produktionsvolym och lägre kassationskostnader krävs åtgärder. Ett viktigt åtgärdsförslag för minskade kassationskostnader är standardisering av skenornas krökning. För tidsbesparing är åtgärden förspänning av master den enskilda åtgärden med störst påverkan.

    Tillverkning av master varierar kraftigt med säsong, där vår utgör topp medan vintern utgör dal. Då all koning sker mot kundorder råder därmed en viss överkapacitet. Tillverkningen är hantverksmässig vilket medför låg volymflexibilitet då koning kräver utbildad personal. I dag finns endast 3 operatörer vid mastavdelningen som behärskar koning, övriga kan visserligen avlasta men för att koning skall kunna utföras krävs närvaro av någon av dessa tre.

    Bland åtgärdsförslagen nämns öppen fixtur vilket kom till för att förenkla hanteringen av master. I dagsläget måste en AGV-vagn, som används vid pressens verktygshantering, stoppas av operatör vid koning av längre master. Detta för att masten måste laddas i längdled vilket kräver extra utrymme. En öppen fixtur förenklar förflyttningen av mast avsevärt men vilken tidsbesparing som nås är svår att uppskatta.

  • 7.
    Adrodegari, Federico
    et al.
    University of Brescia, Italy.
    Saccani, Nicola
    University of Brescia, Italy.
    Kowalkowski, Christian
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell ekonomi. Linköpings universitet, Tekniska fakulteten. Hanken School Econ, Finland.
    A framework for PSS business models: formalization and application2016Ingår i: PRODUCT-SERVICE SYSTEMS ACROSS LIFE CYCLE, ELSEVIER SCIENCE BV , 2016, Vol. 47, s. 519-524Konferensbidrag (Refereegranskat)
    Abstract [en]

    In order to successfully move "from products to solutions", companies need to redesign their business model. Nevertheless, service oriented BMs in product-centric firms are under-investigated in the literature: very few works develop a scheme of analysis of such BMs. To provide a first step into closing this gap, we propose a new framework to describe service-oriented BMs, pointing out the main BM components and related PSS characteristics. Thus, the proposed framework aims to help companies to take into account the relevant elements that need to be designed to successfully implement a service-oriented BM and thus guide strategic decisions. (C) 2016 The Authors. Published by Elsevier B.V.

  • 8.
    Adrodegari, Federico
    et al.
    University of Brescia, Italy.
    Saccani, Nicola
    University of Brescia, Italy.
    Kowalkowski, Christian
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell ekonomi. Linköpings universitet, Tekniska fakulteten. Hanken School Econ, Finland.
    Vilo, Jyrki
    KINE Robot Solut, Finland.
    PSS business model conceptualization and application2017Ingår i: Production planning & control (Print), ISSN 0953-7287, E-ISSN 1366-5871, Vol. 28, nr 15, s. 1251-1263Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The discussion about business models has gained considerable attention in the last decade. Business model frameworks have been developed in the literature as management methods helping companies to comprehend and analyse their current business logic and guide the deployment of new strategies. In response to calls for a deeper understanding of the application of a business model approach to product-service systems (PSS), this study develops a two-level hierarchical framework that (i) includes a set of components with pertinent, second-order variables to take into account when undergoing the shift from products to solutions; (ii) supports industrial companies, especially SMEs, in designing their future business model and in consistently planning the actions needed to implement it. The framework was applied and refined within real-life settings. The application to KINE - a robot solutions supplier - shows how key challenges faced by servitization firms may be thoroughly addressed through the adoption of a business model perspective.

  • 9.
    Aeeni, Soheila
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion.
    Development of an Open-source Multi-objective Optimization Toolbox2019Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The industrial trend is currently to increase product customization, and at the same time decrease cost, manufacturing errors, and time to delivery. These are the main goal of the e-FACTORY project which is initiated at Linköping university to develop a digital framework that integrates digitization technologies to stay ahead of the competitors. e-FACTORY will help companies to obtain a more efficient and integrated product configuration and production planning process.

    This thesis is a part of the e-FACTORY project with Weland AB which main mission is the optimization of spiral staircase towards multiple disciplines such a scost and comfortability. Today this is done manually and the iteration times are usually long. Automating this process could save a lot of time and money.

    The thesis has two main goals, the first part is related to develop a generic multi-objective optimization toolbox which contains NSGA-II and it is able to solve different kinds of optimization problems and should be easy to use as much as possible. The MOO-toolbox is evaluated with different kinds of optimization problems and the results were compared with other toolboxes. The results seem confident and reliable for a generic toolbox. The second goal is to implement the optimization problem of the spiral staircase in the MOO-toolbox. The optimization results achieved in this thesis shows the benefits of optimization for this case and it can be extended by more variables to obtain impressive results.

  • 10.
    Aevan, Nadjib Danial
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system.
    MDO Framework for Design of Human PoweredPropellers using Multi-Objective Genetic Algorithm2015Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This thesis showcases the challenges, downsides and advantages to building a MultiDisciplinary Optimization (MDO) framework to automate the generation of an efficientpropeller design built for lightly loaded operation, more specifically for humanpowered aircrafts. Two years ago, a human powered aircraft project was initiatedat Linköping University. With the help of several courses, various students performedconceptional design, calculated and finally manufactured a propeller bymeans of various materials and manufacturing techniques. The performance ofthe current propeller is utilized for benchmarking and comparing results obtainedby the MDO process.The developed MDO framework is constructed as a modeFRONITER project wereseveral Computer Aided Engineering softwares (CAE) such as MATLAB, CATIAand XFOIL are connected to perform multiple consequent optimization subprocesses.The user is presented with several design constraints such as blade quantity,required input power, segment-wise airfoil thickness, desired lift coefficientetc. Also, 6 global search optimization algorithms are investigated to determinethe one which generate most efficient result according to several set standards.The optimization process is thereafter initialized by identifying the most efficientchord distribution with a help of an initial blade cross-section which has been previouslyused in other human powered propellers, the findings are thereafter usedto determine the flow conditions at different propeller stations. Two different aerodynamicoptimized shapes are generated with the help of consecutively performedsubprocesses. The optimized propeller requires 7.5 W less input power to generatenearly equivalent thrust as the original propeller with a total efficiency exceedingthe 90 % mark (90.25 %). Moreover, the MDO framework include an automationprocess to generate a CAD design of the optimized propeller. The generatedCAD file illustrates a individual surface blade decrease of 12.5 % compared tothe original design, the lightweight design and lower input power yield an overallpropulsion system which is less tedious to operate.

  • 11.
    Agmell, M.
    et al.
    Lund University, Sweden.
    Ahadi, A.
    Lund University, Sweden.
    Zhou, J. M.
    Lund University, Sweden.
    Peng, Ru
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Konstruktionsmaterial. Linköpings universitet, Tekniska fakulteten.
    Bushlya, V.
    Lund University, Sweden.
    Stahl, J. -E.
    Lund University, Sweden.
    Modeling subsurface deformation induced by machining of Inconel 7182017Ingår i: Machining science and technology, ISSN 1091-0344, E-ISSN 1532-2483, Vol. 21, nr 1, s. 103-120Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Traditionally, the development and optimization of the machining process with regards to the subsurface deformation are done through experimental method which is often expensive and time consuming. This article presents the development of a finite element model based on an updated Lagrangian formulation. The numerical model is able to predict the depth of subsurface deformation induced in the high- speed machining of Inconel 718 by use of a whisker-reinforced ceramic tool. The effect that the different cutting parameters and tool microgeometries has on subsurface deformation will be investigated both numerically and experimentally. This research article also addresses the temperature distribution in the workpiece and the connection it could have on the wear of the cutting tool. The correlation of the numerical and experimental investigations for the subsurface deformation has been measured by the use of the coefficient of determination, R-2. This confirms that the finite element model developed here is able to simulate this type of machining process with sufficient accuracy.

  • 12.
    Ahlbert, Gabriella
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Hållfasthetslära. Linköpings universitet, Tekniska högskolan.
    Method Evaluation of Global-Local Finite Element Analysis2012Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    When doing finite element analysis upon the structure of Saab’s aeroplanes a coarse global model of mainly shell elements is used to determine the load distribution for sizing the structure. At some parts of the aeroplane it is however desirable to implement a more detailed analysis. These areas are usually modelled with solid elements; the problem of connecting the fine local solid elements to the coarse global model will shell elements then arises.

     

    This master thesis is preformed to investigate possible Global-Local methods to use for the structural analysis on Gripen. First a literature study of current methods on the market is made, thereafter a few methods are implemented on a generic test structure and later on also tested on a real detail of Gripen VU. The methods tested in this thesis are Mesh refinement in HyperWorks, RBE3 in HyperWorks, Glue in MSC Patran/Nastran and DMIG in MSC Nastran. The software is however not evaluated in this thesis, and a further investigation is recommended to find the most fitting software for this purpose. All analysis are performed with linear assumptions.

     

    Mesh refinement is an integrated technique where the elements are gradually decreasing in size. Per definition, this technique cannot handle gaps, but it has almost identical results to the fine reference model.

     

    RBE3 is a type of rigid body elements with zero stiffness, and is used as an interface element. RBE3 is possible to use to connect both Shell-To-Shell and Shell-To-Solid, and can handle offsets and gaps in the boundary between the global and local model.

     

    Glue is a contact definition and is also available in other software under other names. The global respectively the local model is defined as contact bodies and a contact table is used to control the coupling. Glue works for both Shell-To-Shell and Shell-To-Solid couplings, but has problem dealing with offsets and gaps in the boundary between the global and local model.

     

    DMIG is a superelement technique where the global model is divided into smaller sub-models which are mathematically connected. DMIG is only possible to use when the nodes on the boundary on the local model have the same position as the nodes at the boundary of the global model. Thus, it is not possible to only use DMIG as a Global-Local method, but can advantageously be combined with other methods.

     

    The results indicate that the preferable method to use for Global-Local analysis is RBE3. To decrease the size of the files and demand of computational power, RBE3 can be combined with a superelement technique, for example DMIG.

     

    Finally, it is important to consider the size of the local model. There will inevitably be boundary effect when performing a Global-Local analysis of the suggested type, and it is therefore important to make the local model big enough so that the boundary effects have faded before reaching the area of interest.

  • 13.
    Ahlman, Per-Arne
    Linköpings universitet, Institutionen för konstruktions- och produktionsteknik, Maskinkonstruktion.
    Smörjning Av Lager2009Självständigt arbete på grundnivå (högskoleexamen), 15 poäng / 22,5 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The work thesis was performed at Assalub a company which is situated in Åtvidaberg. The company works with developing, manufacturing and marketing equipment for handling of lubricants for light and heavier industry. The work thesis it is based on a inquiry Assalub got from MacGregor which is a company within cargo solution, from port to offshore system.

    For unloading grain and other material from the ship cargo it is used combined inlet feeder and screw conveyor, there the inlet feeder is drilling down through the cargo and feed the screw conveyer with material to further destination. At the bottom of the screw conveyer and the inlet feeder there is a bearing that keep the parts together. However the lubrication of the bearing must be made manually. Until now the bearing was lubricated manually through a grease nipple from the bottom of the drill once a day.

     

    The purpose of the thesis was the construction of a lubricating system namely a pump with a grease container which should be placed inside the space of the screw conveyer, so the bearing will be continually lubricated and able to work several days without any stoppage.

    After receiving drawings and operating data for the screw conveyer, the details for the construction was designed in CAD system Solid Edge. The solid mechanics calculations on the weakest point on the construction was made by hand and afterwards the drawings for respectively details was made.

    The construction was completed, but because of the time limit for this work thesis, the manufacturing, mounting and testing were not included in these weeks. The grease containers capacity is approximately seventy-two hours, although desirable should be up to seven days. According to the solid mechanics calculations, the construction should have no problem to resist the stresses it would be exposed to.

    Since this is a prototype there is probably some adjustments and improvements to do, but the estimating is that the system should work properly as it is now.

  • 14.
    Ahmad, Maqsood
    et al.
    Base Engine & Materials Technology, Volvo Group, Gothenburg.
    Peng, Ru
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Konstruktionsmaterial. Linköpings universitet, Tekniska fakulteten.
    König, Mathias
    Materials Technology for Basic Engine, Scania CV, Södertälje.
    Johansson, Sten
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Konstruktionsmaterial. Linköpings universitet, Tekniska fakulteten.
    Bending Fatigue Behavior of Blast Cleaned Grey Cast Iron2017Ingår i: Residual Stresses 2016: ICRS-10, Materials Research Proceedings 2 (2016), 2017, Vol. 2, s. 193-198Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper presents a detailed study on the effect of an industrial blast cleaning process on the fatigue behavior of a grey cast iron with regard to the residual stresses and microstructural changes induced by the process. A comparison was also made to the effect of a machining operation which removed the casting skin layer. The blast cleaning process was found to greatly improve the fatigue resistance in both the low and high cycle regimes with a 75% increase in the fatigue limit. Xray diffraction measurements and scanning electron microscopic analyses showed that the improvement was mainly attributed to compressive residual stresses in a surface layer up to 800 μm in thickness in the blast cleaned specimens. The machining also gave better fatigue performance with a 30% increase in the fatigue limit, which was ascribed to the removal of the weaker casting skin layer.

  • 15.
    Ahrén, Mats
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling.
    Dahllöf, Martin
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling.
    Utformning av planerings- och styrningssystem för tillverkning av luckor till Boeing 787: en studie vid Saab Aerostructures2008Självständigt arbete på grundnivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats
    Abstract [sv]

    Saab Aerostructures är en del av Saab-koncernen och företaget utvecklar och tillverkar strukturer för flygindustrin. Tillverkningen av stridsflygplan är den dominerande verksamheten, men antalet civila projekt ökar stadigt. I många av de civila projekten verkar Saab Aerostructures som underleverantör till antingen Boeing eller Airbus. Det finns flera skillnader mellan de militära och de civila projekten, exempelvis är leveranstakten betydligt högre i de civila projekten. I och med de förändrade förutsättningarna görs försök med att tillämpa lean production. Detta har påbörjats i två pilotprojekt varav ett är tillverkningen av luckor till Boeing 787.

    Syftet med denna rapport är att komma med rekommendationer för hur produktionen av luckor till Boeing 787 skall planeras och styras. Då företaget började använda ett nytt ERP-system under hösten 2006, är det även av intresse att se hur detta system skall användas utefter de rekommendationer som uppkommer. För att utreda dessa frågor undersöks både produktionsstrategiska och operativa aspekter i de två produktionsavsnitten Sammanbyggnad och Kompositverkstad.

    Sammanlagt tillverkas sju olika luckor, varav de två största produceras i en lina som håller en jämn produktionstakt. Projektet är försenat, bland annat på grund av svårigheter att tillverka de 20 kompositartiklar som ingår i de tre största luckorna. Komposittillverkningen sker i en funktionell verkstad, med många transporter mellan byggnader för att knyta ihop flödet. Undersökningen visar att Saab Aerostructures har en mismatch mellan planeringsstrategin och den kapacitetsstrategi som tillämpas i Kompositverkstaden. Företaget försöker följa den efterfrågan de olika projekten har, men har samtidigt ont om kapacitet. Det leder till överbeläggning och leveranssvårigheter. På grund av kapacitetsbristen bör en cyklisk planering användas i Kompositverkstaden, där flaskhalsen styr takten. På detta sätt kan kötiderna i verkstaden minskas. Kompositverkstaden bör bli mer flödesinriktad för att minska ledtider och få till en enklare styrning. På detta sätt blir det möjligt att hålla en jämn leveranstakt även för dessa artiklar.

    Tillverkningstider, kötider och transporttider i ERP-systemet bör anpassas efter den cykliska planeringen som tas fram. Att uppdatera dessa tider blir extra viktigt i inkörningsförloppet, då tiderna är betydligt längre och varierar kraftigt. På grund av den hantverksmässiga produktionen i Kompositverkstaden och den stora kassationsrisken som föreligger är det viktigt att införa säkerhetsmekanismer. När den cykliska planeringen tas fram bör en säkerhetsledtid användas för de operationer som har stor variation i operationstid. För att inte linan skall stå stilla vid störningar är det även viktigt att skapa buffertar, dels innan linan men även framför den flaskhals som identifieras i flödet.

    Produktionstakten för kompositartiklarna är högre än takten i Sammanbyggnad, vilket inte stöds av ERP-systemet. För att systemet ändå skall föreslå rätt antal tillverkningsorder bör en kassationsfaktor användas. På detta sätt ges stöd för den långsiktiga planeringen. Slutligen visar undersökningen att styrning via ett kanbansystem ej bör genomföras, främst på grund av de höga kassationstalen och produktionsupplägget som en funktionell verkstad.

  • 16.
    Ajdén, Per
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanik.
    Backlund, Carl
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanik.
    Pilotmodeller till flygmekanisk simulator för JAS 39 Gripen2010Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Abstract

    SAAB has for a long time used user controlled pilot models in ARES. ARES is a simulation tool used in the desktop environment for simulations and calculations of the JAS 39 Gripen fighter and other aircraft. ARES stands for ”Aircraft Rigid body Engineering Simulation”. To work with these pilot models has been both time-consuming and inefficient. In this master thesis, new pilot models are developed, where parameters are automatically generated, this will result in that the user doesn’t have to put a lot of work into adjusting the gains for different manoeuvres. This is called gain scheduling.

    To make this possible, simple models of the aircraft were created at different points in the envelope. These models were then used to calculate optimal controllers using LQ-control and pole placement techniques. These models and controllers were then implemented in Simulink. Simulink was then used to test the controllers before they were implemented in ARES.

    Control in all modes except roll attitude and speed by throttle are based on LQ-control in pitch-, roll- and yaw-angular velocity. And through these angular velocities the other angles are controlled by simple controllers, who is generating a reference in angular velocity. The roll attitude controller is based on direct pole placement based upon desired damping and undamped natural frequency, and the speed controller is based upon a model of throttle positions in trimmed states.

    The new pilot models are usable to control:

    • Roll rate
    • Roll attitude
    • Pitch rate
    • Pitch attitude
    • Angle of attack
    • Load factor
    • Yaw attitude
    • Course angle
    • Climb angle
    • Mach number
    • Climb rate

    These controllers can be combined so that the aircraft can perform desired maneuvers.

  • 17.
    Ajjan Godoy, Fátima Nadia
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Biohybrid Polymer Electrodes for Renewable Energy Storage2017Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Daily and seasonally fluctuating energy supply and demand requires adequate energy storage solutions. In recent years electrochemical supercapacitors have attracted considerable attention due to their ability to both store and deliver electrical energy efficiently. Our efforts are focused on developing and optimizing sustainable organic electrode materials for supercapacitors based on renewable bioorganic materials, offering a cheap, environmentally friendly and scalable alternative to store energy. In particular, we are using the second most abundant biopolymer in nature, lignin (Lig), which is an insulating material. However, when used in combination with electroactive and conducting polymers such as polypyrrole (PPy) and poly(3,4-ethylenedioxythiophene) (PEDOT), the biohybrid electrodes PPy/Lig and PEDOT/Lig display significantly enhanced energy storage performance as compared to the pristine conducting polymers without the lignin. Redox cyclic voltammetry and galvanostatic charge/discharge measurements indicate that the enhanced performance is due to the additional pseudocapacitance generated by the quinone moieties in lignin. Moreover, a conjugated redoxpolymer poly(aminoanthraquinone) PAAQ, with intrinsic quinone functions and excellentstability, has been combined with lignin and PEDOT resulting in a trihybrid bioelectrode. PEDOT compensates the low conductivity of PAAQ and provides electrical pathways to the quinone groups. The electrochemically generated quinones undergo a two electron, two protonredox process within the biohybrid electrodes as revealed by FTIR spectroelectrochemistry.These remarkable features reveal the exciting potential of a full organic energy storage device with long cycle life. Therefore, supercapacitor devices were designed in symmetric or asymmetric two electrode configuration. The best electrochemical performance was achieved by the asymmetric supercapacitor based on PEDOT+Lignin/PAAQ as the positive electrode and PEDOT/PAAQ as the negative electrode. This device exhibits superior electrochemical performance and outstanding stability after 10000 charge/discharge cycles due to the synergistic effect of the two electrodes. Finally, we have characterized the response of this supercapacitor device when charged with the intermittent power supply from an organic photovoltaic module. We have designed charging/discharging conditions such that reserve power was available in the storage device at all times. This work has resulted in an inexpensive fully organic system witht he dual function of energy conversion and storage.

    Delarbeten
    1. Biopolymer hybrid electrodes for scalable electricity storage
    Öppna denna publikation i ny flik eller fönster >>Biopolymer hybrid electrodes for scalable electricity storage
    2016 (Engelska)Ingår i: Materials Horizons, ISSN 2051-6347, E-ISSN 2051-6355, Vol. 3, nr 3, s. 174-185Artikel, forskningsöversikt (Refereegranskat) Published
    Abstract [en]

    Powering the future, while maintaining a cleaner environment and a strong socioeconomic growth, is going to be one of the biggest challenges faced by mankind in the 21st century. The first step in overcoming the challenge for a sustainable future is to use energy more efficiently so that the demand for fossil fuels can be reduced drastically. The second step is a transition from the use of fossil fuels to renewable energy sources. In this sense, organic electrode materials are becoming increasingly attractive compared to inorganic electrode materials which have reached a plateau regarding performance and have severe drawbacks in terms of cost, safety and environmental friendliness. Using organic composites based on conducting polymers, such as polypyrrole, and abundant, cheap and naturally occurring biopolymers rich in quinones, such as lignin, has recently emerged as an interesting alternative. These materials, which exhibit electronic and ionic conductivity, provide challenging opportunities in the development of new charge storage materials. This review presents an overview of recent developments in organic biopolymer composite electrodes as renewable electroactive materials towards sustainable, cheap and scalable energy storage devices.

    Ort, förlag, år, upplaga, sidor
    ROYAL SOC CHEMISTRY, 2016
    Nationell ämneskategori
    Annan naturresursteknik
    Identifikatorer
    urn:nbn:se:liu:diva-128741 (URN)10.1039/c5mh00261c (DOI)000375296600002 ()
    Anmärkning

    Funding Agencies|Knut and Alice Wallenberg Foundation; Wallenberg Scholar grant

    Tillgänglig från: 2016-05-31 Skapad: 2016-05-30 Senast uppdaterad: 2017-11-30
    2. Spectroelectrochemical investigation of redox states in a polypyrrole/lignin composite electrode material
    Öppna denna publikation i ny flik eller fönster >>Spectroelectrochemical investigation of redox states in a polypyrrole/lignin composite electrode material
    Visa övriga...
    2015 (Engelska)Ingår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 3, nr 24, s. 12927-12937Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    We report spectroelectrochemical studies to investigate the charge storage mechanism of composite polypyrrole/lignin electrodes. Renewable bioorganic electrode materials were produced by electropolymerization of pyrrole in the presence of a water-soluble lignin derivative acting as a dopant. The resulting composite exhibited enhanced charge storage abilities due to a lignin-based faradaic process, which was expressed after repeated electrochemical redox of the material. The in situ FTIR spectroelectrochemistry results show the formation of quinone groups, and reversible oxidation-reduction of these groups during charge-discharge experiments in the electrode materials. The most significant IR bands include carbonyl absorption near 1705 cm(-1), which is attributed to the creation of quinone moieties during oxidation, and absorption at 1045 cm(-1) which is due to hydroquinone moieties.

    Ort, förlag, år, upplaga, sidor
    ROYAL SOC CHEMISTRY, 2015
    Nationell ämneskategori
    Materialkemi
    Identifikatorer
    urn:nbn:se:liu:diva-120069 (URN)10.1039/c5ta00788g (DOI)000356022800044 ()
    Anmärkning

    Funding Agencies|Knut and Alice Wallenberg foundation; Marie Curie network Renaissance; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009-00971]

    Tillgänglig från: 2015-07-06 Skapad: 2015-07-06 Senast uppdaterad: 2017-12-04
    3. High performance PEDOT/lignin biopolymer composites for electrochemical supercapacitors
    Öppna denna publikation i ny flik eller fönster >>High performance PEDOT/lignin biopolymer composites for electrochemical supercapacitors
    Visa övriga...
    2016 (Engelska)Ingår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 4, nr 5, s. 1838-1847Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Developing sustainable organic electrode materials for energy storage applications is an urgent task. We present a promising candidate based on the use of lignin, the second most abundant biopolymer in nature. This polymer is combined with a conducting polymer, where lignin as a polyanion can behave both as a dopant and surfactant. The synthesis of PEDOT/Lig biocomposites by both oxidative chemical and electrochemical polymerization of EDOT in the presence of lignin sulfonate is presented. The characterization of PEDOT/Lig was performed by UV-Vis-NIR spectroscopy, FTIR infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, cyclic voltammetry and galvanostatic charge-discharge. PEDOT doped with lignin doubles the specific capacitance (170.4 F g(-1)) compared to reference PEDOT electrodes (80.4 F g(-1)). The enhanced energy storage performance is a consequence of the additional pseudocapacitance generated by the quinone moieties in lignin, which give rise to faradaic reactions. Furthermore PEDOT/Lig is a highly stable biocomposite, retaining about 83% of its electroactivity after 1000 charge/discharge cycles. These results illustrate that the redox doping strategy is a facile and straightforward approach to improve the electroactive performance of PEDOT.

    Ort, förlag, år, upplaga, sidor
    ROYAL SOC CHEMISTRY, 2016
    Nationell ämneskategori
    Biologiska vetenskaper
    Identifikatorer
    urn:nbn:se:liu:diva-125323 (URN)10.1039/c5ta10096h (DOI)000368839200035 ()
    Anmärkning

    Funding Agencies|Power Papers project from the Knut and Alice Wallenberg foundation; Wallenberg Scholar grant from the Knut and Alice Wallenberg foundation; Marie Curie network Renaissance (NA); European Research Council by Starting Grant Innovative Polymers for Energy Storage (iPes) [306250]; Basque Government

    Tillgänglig från: 2016-02-23 Skapad: 2016-02-19 Senast uppdaterad: 2017-11-30
  • 18.
    Alayón González, Claudia Juliana
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Kvalitetsteknik.
    Research Trends in Quality Management over the years 2010-20112012Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    In current globalized and highly demanding markets, Quality does not constitute any more a competitive advantage for organizations. Instead, Quality represents a basic market entry requirement for organizations indistinguishable from the country or economic sector they belong to.

    Being conscious of the importance of Quality for all type of organizations, the purpose of this thesis is to contribute to the identification and better understanding of current trends in academic research on Quality Management. By analyzing a sample of 612 academic papers collected from five international Quality journals and two QMOD international conferences over 2010 and 2011, the author will study and reflect on the current trends of global academic research related to Quality Management.

    Literature review was used as research methodology for the thesis. Academic papers were categorized, classified and analyzed in order to identify current research trends on Quality Management.

    This work provides a snapshot of the current research trends on Quality Management. It benefits the educational sector, researchers, industry and practitioners by presenting an overview of the current research needs as well as potential future research topics.

    As a result of this study, five main trending research topics on Quality Management were identified: management systems standards, total quality management, service quality, customer related processes after delivering product/service and excellence models.

    China, India, USA, Sweden and UK were identified as the countries that have published the highest number of academic papers in international Quality journals during the studied period. Additionally, it was found a marked predominance of academic research on Quality Management towards the service sector.

    These results and the answers to five proposed research questions were discussed and solved in this report.

  • 19.
    Albrektsson, Jörgen
    et al.
    Linköpings universitet, Institutionen för systemteknik, Fordonssystem. Linköpings universitet, Tekniska fakulteten. Volvo Construction Equipment, Eskilstuna, Sweden.
    Åslund, Jan
    Linköpings universitet, Institutionen för systemteknik, Fordonssystem. Linköpings universitet, Tekniska fakulteten.
    Fuel Optimal Control of an Articulated Hauler Utilising a Human Machine Interface2019Ingår i: Smart Cities, Green Technologies, and Intelligent Transport Systems / [ed] Donnellan, Brian; Klein, Cornel; Helfert, Markus; Gusikhin, Oleg; Pascoal, António, Springer International Publishing , 2019, s. 190-208Konferensbidrag (Refereegranskat)
    Abstract [en]

    Utilising optimal control presents an opportunity to increase the fuel efficiency in an off-road transport mission conducted by an articulated hauler. A human machine interface (HMI) instructing the hauler operator to follow the fuel optimal vehicle speed trajectory has been developed and tested in real working conditions. The HMI implementation includes a Dynamic Programming based method to calculate the optimal vehicle speed and gear shift trajectories. Input to the optimisation algorithm is road related data such as distance, road inclination and rolling resistance. The road related data is estimated in a map module utilising an Extended Kalman Filter (EKF), a Rauch-Tung-Striebel smoother and a data fusion algorithm. Two test modes were compared: (1) The hauler operator tried to follow the optimal vehicle speed trajectory as presented in the HMI and (2) the operator was given a constant target speed to follow. The objective of the second test mode is to achieve an approximately equal cycle time as for the optimally controlled transport mission, hence, with similar productivity. A small fuel efficiency improvement was found when the human machine interface was used.

  • 20.
    Alder, Magnus
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Ekonomiska informationssystem.
    Peterson, Jimmy
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Ekonomiska informationssystem.
    Enhanced knowledge utilization for increased project efficiency: A study of knowledge management in a project environment at Siemens Industrial Turbomachinery2010Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    I dagens osäkra och ständigt föränderliga affärsklimatet har kunskap blivit den enda säkra källan till långsiktig konkurrenskraft. Att lära sig av misstag och undvika att återuppfinna hjulet är idag av yttersta vikt; dagens organisationer har helt enkelt inte råd med att inte använda sin kunskap på bästa sätt. I och med att Siemens Industrial Turbomachinery AB (SIT) verkar i en komplex och högteknologisk industri är det absolut nödvändigt att tillvarata och använda den kunskap som finns internt. Det har emellertid kommit till författarnas insikt att projektledningsavdelningen (GL) inom gas divisionen på SIT upplever ett behov av förbättrade processer för kunskapshantering och återanvändning av den kunskapsbas som finns inom organisationen.

    Den första januari 2010 genomförde Siemens AG en stor omorganisation vilket innebar att två tidigare separata projektledningsavdelningar inom SIT och GL slogs ihop till en enhet. Det nuvarande arbetet med att harmonisera de två avdelningarnas tidigare arbetssätt medför en fördelaktig tidpunkt för att se över och undersöka hur organisationen bör förbättra sin kunskapshantering framöver. Med detta som bakgrund har det följande examensarbetet fokuserat på att undersöka och belysa de förbättringsmöjligheter som finns gällande spriding av kunskap internt mellan projekt och mellan projekt och den övriga organisationen. Vidare studerar rapporten hur verktyg och processer bör utformas för att samla in, bevara, sprida och återanvända erfarenheter, kunskaper och lärdomar inom en projektbaserad organisation på bästa möjliga sätt.

    Studiens tillvägagångssätt är av kvalitativ karaktär och inkluderar intervjuer med de 16 projektledarna inom GL samt med andra nyckelpersoner inom både SIT och de nya affärsenheterna CS och IP inom Siemens Oil & Gas division. Medverkan i projektledarmöten och observationer av projektledarna i deras dagliga verksamhet har vidare bidragit till en fördjupad förståelse av den nuvarande situationen inom SIT och GL; en förståelse som visat sig nödvändig för att kartlägga de faktorer och bakomliggande orsaker som gett upphov till organisationens låga kunskapsbevarande och användning av intern kunskap; en förståelse som gett upphov till den modell som belyser de viktiga aspekterna för att uppnå framgångsrik kunskapshantering, och dessas beroende och påverkan på varandra.

    För att förbättra den interna kunskapsanvändningen krävs att lärdomar och erfarenheter samlas in kontinuerligt under hela projektets livscykel. Insamlandet bör primärt ske genom dagens regelbundna projektmöten tillsammans med specifika workshops avsedda för att tillvarata erfarenheter och lärdomar. Insamlandet och användningen av lärdomar bör på detta sett integreras i projektledningsprocessen. Det finns även ett behov av att förbättra och utveckla organisationens forum för kunskapsdelning; vilka behövs för att möjliggöra att humankapital kan omvandlas till strukturkapital, vilket leder till att organisationens kunskapsbas utökas. Förbättrade forum tillsammans med ett visualiserat stöd från ledningen genom handling, feedback och införandet av en organisationskultur som förespråkar ett organisatoriskt lärande, ser gemensamt till att förbättra bevarandet och användandet av organisationens kunskapsbas.

    Även om tillvägagångssättet för denna studie baseras på en fallstudie av SIT:s organisation anses slutsatserna kunna vara av värde för andra projektbaserade organisationer; slutsatserna anses därmed generaliserbara och tillämpbara inom andra branscher. Den allmänna slutsatsen av denna studie är att ett framgångsrikt kunskapshanteringssystem bör beakta och involvera alla faktorer i den presenterade modellen.

  • 21.
    Aldén, Elin
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell Produktion. Linköpings universitet, Tekniska högskolan.
    Hantering av digitala verktygsmodeller: En studie av hur 3D-modeller av monteringsverktyg ska lagras, struktureras och geopositioneras på Scania CV AB inom Chassimontering2012Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    På grund av ökad produktkomplexitet och digitala arbetssätt har fler företag insett nyttan i att implementera och använda sig av bra system för Produkt Lifecycle Management och Product Data Management för att hantera produkten genom dess livscykel. Funktionen hos PLM-system är framförallt att se till att alla har tillgång till den senast uppdaterade datan. Detta uppnås genom ett centralt ställe att lagra produktdata samt möjlighet att strukturera och hantera datan. Scania använder sig av Spectra och Enovia för att strukturera och lagra dagens konstruktionsdata. På senare år har digital provmontering införts i chassiproduktion som ett komplement till den fysiska provmonteringen. Detta för att digitalt simulera monterbarhet av nya artiklar innan de går ut i produktion.

    På provmonteringen på chassiavdelningen MSPAP har det upptäckts ett behov av att bättre lagra och strukturera de verktygsmodeller som används under provmonteringar. Framförallt behövs det skapas en större tillgänglighet till modellerna. Verktygsmodellerna används för att simulera åtkomst för verktyg vid montering. Examensarbetet utförs för att se över införandet av Enovia och Spectra även i produktionen för att hantera den ökade mängden 3D-modeller som idag lagras på processteknikernas egna datorer.

    Två metoder för att importera befintliga och framtida 3D-modeller in till Enovia har tagits fram. Det är processteknikerna i produktion som gör verktygsinvesteringar och därför ska de utföra importerna till Enovia när de får in nya ritningar/modeller från verktygsleverantörer. En teststruktur byggdes även upp i Spectra, Scanias PLM-system utefter dagens monteringssekvens på chassiline. En undersökning av hur verktygsmodeller ska positioneras geometriskt i den digitala miljön har också genomförts.

    Studien visade att chassiproduktion borde införa Enovia för lagring av modeller, och även se över strukturering och möjlighet till geopositionering, av verktygsmodeller. För att geopositionering ska ske korrekt krävs det att systemstöd tas fram även för verktygsmodeller och inte bara för produkter som finns idag.

    För att chassiavdelningen och Scania i stort ska förbättra sin utvecklingsprocess och minska omtag och slöseri bör kommunikationen mellan produktion och utveckling bli bättre. Kommunikation kommer att förbättra utnyttjandet av varandras kunskaper och resurser. Scania borde även ställa högre krav på sina underleverantörer av verktyg såsom krav på leverans av 3D-material för att underlätta sin strävan mot ett digitalt arbetssätt i en 3D-miljö.

  • 22.
    Alegret, Guillem
    et al.
    MAN Diesel & Turbo, Copenhagen, Denmark.
    Llamas, Xavier
    Linköpings universitet, Institutionen för systemteknik, Fordonssystem. Linköpings universitet, Tekniska fakulteten.
    Vejlgaard-Laursen, Morten
    MAN Diesel & Turbo, Copenhagen, Denmark.
    Eriksson, Lars
    Linköpings universitet, Institutionen för systemteknik, Fordonssystem. Linköpings universitet, Tekniska fakulteten.
    Modeling of a Large Marine Two-Stroke Diesel Engine with Cylinder Bypass Valve and EGR System2015Ingår i: 10th IFAC Conference on Manoeuvring and Control of Marine Craft MCMC 2015: Copenhagen, 24–26 August 2015 / [ed] Roberto Galeazzi and Mogens Blanke, IFAC Papers Online, 2015, Vol. 48, s. 273-278Konferensbidrag (Refereegranskat)
    Abstract [en]

    A nonlinear mean value engine model (MVEM) of a two-stroke turbocharged marine diesel engine is developed, parameterized and validated against measurement data. The goal is to have a computationally fast and accurate engine model that captures the main dynamics and can be used in the development of control systems for the newly introduced EGR system. The tuning procedure used is explained, and the result is a six-state MVEM with seven control inputs that capture the main system dynamics.

  • 23.
    Alfredson, Jens
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell arbetsvetenskap. Linköpings universitet, Tekniska högskolan.
    Differences in Situational Awareness and How to Manage Them in Development of Complex Systems2007Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Situationsmedvetenhet (Eng. Situational Awareness), (SA), handlar om att ha koll på läget och vara medveten om vad som händer. Redan då ett komplext system utvecklas får vi en möjlighet att påverka vilken SA en framtida användare av systemet kan komma att få. Det gäller att ta tillvara på detta tillfälle! Ibland uppträder skillnader i SA, beroende på en rad olika orsaker. Denna avhandling handlar om SA och hur man kan använda de skillnaderna vid utveckling av komplexa system. Detta är relevant vid utveckling av en rad olika typer av komplexa system, även om de flesta exempel i denna avhandling kommer från flygdomänen.

    Avhandlingen innehåller beskrivningar hämtade från litteratur inom området och förslag på utveckling av SA-teori utifrån fokus på just skillnader. Skillnaden mellan vad du behöver vara medveten om och vad du verkligen är medveten om föreslås ge en indikation om individens SA. Vidare föreslås skillnaden mellan vad du är medveten om och vad du tror dig vara medveten om också ge en indikation om individens SA. SA kan skattas för en grupp av människor som arbetar tillsammans, genom variationerna i hur samstämmiga deras uppfattningar är.

    Termen situationshantering (Eng. Situation Management), (SM), föreslås med en vidare mening än SA, inkluderande SA, men också varje del av perceptionscykeln, hantering av mentala resurser och hantering av situationen genom extern påverkan. SM är en väl lämpad term vid utveckling av komplexa system då fokus här är på situationen och hur den kan hanteras, snarare än fokus på vad en individ eller en grupp uppfattar.

    Att skatta skillnader i SA och att kunna särskilja olika typer av skillnader är viktiga förutsättningar för att kunna hantera skillnader i SA vid utveckling av komplexa system på ett bra sätt. I avhandlingen gås flera sätt att skatta sådana skillnader igenom och speciellt tas för- och nackdelar med ögonrörelsemätning upp. Med referens till litteraturen och till de bilagda artiklarna beskrivs skillnader i SA beroende på a) designalternativ, b) roller i processen från utveckling till användning c) kontext och d) analysnivå. Skillnaderna i SA föreslås ses som både kvantitativa (dvs. hög eller låg SA) och kvalitativa (tex. olika aspekter av en situation).

    Ansatser såsom SM, realtidsvärdering, mätning och analys av SA på flera nivåer samtidigt samt simulatorbaserad design föreslås för att hantera skillnader i SA vid utveckling av komplexa system.

    Delarbeten
    1. Improvement of tactical situation awareness with colour-coded horizontal-situation displays in combat aircraft
    Öppna denna publikation i ny flik eller fönster >>Improvement of tactical situation awareness with colour-coded horizontal-situation displays in combat aircraft
    Visa övriga...
    1999 (Engelska)Ingår i: Displays (Guildford), ISSN 0141-9382, E-ISSN 1872-7387, Vol. 20, nr 4, s. 171-184Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    In the multi-role combat aircraft Gripen, the monochrome head-down displays in the cockpit are to be upgraded in colour. In the present study, the effects of colour-coded displays on visual search and situation awareness (SA) were studied in a real-time simulation of an air-to-air mission with test pilots as subjects. Gripen's monochrome colour scheme was compared to two chromatic (dichrome, polychrome) colour schemes. A 3×2×2 factorial within subjects design was used; the three colour schemes each with two different background conditions (simple and complex) and two different symbol configurations. The pilot had two tasks during the simulation: (1) to track a manoeuvring aircraft within specified limits by using the head-up display (HUD), and (2) to detect the appearance of a priority target on the head-down horizontal-situation display (HSD). Deviations in flight path angle and reaction times for target detection were recorded. After the test runs, the pilot answered questions and ranked the colour schemes in different respects. The pilot also rated them for SA using a subjective rating technique on cognitive compatibility (CC-SART). The results show that colour is advantageous in comparison to the monochrome display: The ranks on situation awareness and preference ratings were higher for the chromatic schemes, and with the complex background, the reaction times were significantly lower for the polychrome colour code. In summary, the results indicate that colour can improve tactical SA in combat aircraft.

    Nyckelord
    Human factors, Aviation, Moving map cockpit displays, Horizontal-situation displays, Electronic maps, Colour coding
    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-12751 (URN)10.1016/S0141-9382(99)00022-0 (DOI)
    Tillgänglig från: 2007-11-09 Skapad: 2007-11-09 Senast uppdaterad: 2017-12-14Bibliografiskt granskad
    2. Pilots’ understanding of situational awareness
    Öppna denna publikation i ny flik eller fönster >>Pilots’ understanding of situational awareness
    2000 (Engelska)Ingår i: Proceedings of the 10th European Conference on Cognitive Ergonomics, 2000, s. 172-181Konferensbidrag, Publicerat paper (Refereegranskat)
    Nationell ämneskategori
    Samhällsvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-12752 (URN)
    Konferens
    10th European Conference on Cognitive Ergonomics, Linköping, Sweden, 21-23 August 2000
    Tillgänglig från: 2007-11-09 Skapad: 2007-11-09 Senast uppdaterad: 2015-03-02Bibliografiskt granskad
    3. Mode monitoring and call-outs: An eye-tracking study of 2-crew automated flight deck operations
    Öppna denna publikation i ny flik eller fönster >>Mode monitoring and call-outs: An eye-tracking study of 2-crew automated flight deck operations
    2006 (Engelska)Ingår i: The International journal of aviation psychology, ISSN 1050-8414, E-ISSN 1532-7108, Vol. 16, nr 3, s. 263-275 Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Mode awareness has been suggested as a critical factor in safe operations of automated aircraft. This study investigated mode awareness by measuring eye point of gaze of both pilots during simulated commercial flights, while recording call-outs and tracking aircraft performance. The results of this study show that the compliance to manufacturer or air carrier procedures regarding mode monitoring and call-outs was very low. However, this did not seem to have a negative effect on the flight path or safety during our observations. Crews exhibited a proliferation of strategies to keep track of status and behavior of the automation, often with little reliance on the flight mode annunciations of the primary flight display. The data confirm the limitations of current flight mode annunciator designs, and suggest that mode awareness is a more complex phenomenon than what can be captured by measuring eye point of gaze and communication alone.

    Ort, förlag, år, upplaga, sidor
    Taylor & Francis, 2006
    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-12753 (URN)10.1207/s15327108ijap1603_2 (DOI)
    Tillgänglig från: 2007-11-09 Skapad: 2007-11-09 Senast uppdaterad: 2017-12-14Bibliografiskt granskad
    4. Effect of task complexity and decision maker separation on shared situational awareness in command and control in network centric warfare
    Öppna denna publikation i ny flik eller fönster >>Effect of task complexity and decision maker separation on shared situational awareness in command and control in network centric warfare
    2007 (Engelska)Ingår i: Military Psychology, ISSN 0899-5605, E-ISSN 1532-7876Artikel i tidskrift (Refereegranskat) Submitted
    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-12754 (URN)
    Tillgänglig från: 2007-11-09 Skapad: 2007-11-09 Senast uppdaterad: 2018-08-01Bibliografiskt granskad
    5. Individual differences in visual behaviour in simulated flight
    Öppna denna publikation i ny flik eller fönster >>Individual differences in visual behaviour in simulated flight
    2002 (Engelska)Ingår i: Proceedings of IS &T/SPIE's 14th Annual Symposium: Vol. 4662. Human Vision and Electronic Imaging VII, 2002, s. 494-502Konferensbidrag, Publicerat paper (Refereegranskat)
    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-12755 (URN)
    Tillgänglig från: 2007-11-09 Skapad: 2007-11-09 Senast uppdaterad: 2009-02-12Bibliografiskt granskad
    6. Business process reengineering in the automotive area by simulator-based design
    Öppna denna publikation i ny flik eller fönster >>Business process reengineering in the automotive area by simulator-based design
    2007 (Engelska)Ingår i: Simulation and Modeling: Current Technologies and Applications / [ed] Asim Abdel Rahman El Sheikh, Abid Al Ajeeli, Evon M. O. Abu-Taieh, Hershey, PA, USA: IGI-Global Inc. , 2007, 1, s. 337-358Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Abstract [en]

    The science of simulation and modeling (SM) strives to showcase the highest possible level of reality in order to determine the conditions necessary for optimal performance. SM is a multifaceted and complex field due to the numerous applications involved, particularly since SM applications range from nuclear reaction to supermarket queuing. Simulation and Modeling: Current Technologies and Applications includes examinations of current issues related to simulation such as: Web-based simulation, virtual reality, augmented reality, and artificial intelligence. This book combines different methods, views, theories, and applications of simulations into one volume, and offers insight into the computer science aspect of simulation and modeling while integrating the business practices of SM.

    Ort, förlag, år, upplaga, sidor
    Hershey, PA, USA: IGI-Global Inc., 2007 Upplaga: 1
    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-12756 (URN)978-15-9904-198-8 (ISBN)159-90-4198-7 (ISBN)
    Tillgänglig från: 2007-11-09 Skapad: 2007-11-09 Senast uppdaterad: 2013-06-28Bibliografiskt granskad
  • 24.
    Alfredson, Jens
    et al.
    Linköpings universitet, Institutionen för datavetenskap. Linköpings universitet, Tekniska fakulteten. Saab Aeronaut, Linkoping, Sweden.
    Trabasso, Luís Gonzaga
    Linköpings universitet, Institutionen för datavetenskap, Interaktiva och kognitiva system. Linköpings universitet, Tekniska fakulteten. ITA, Brazil.
    Blomstrand, Niklas
    Linköpings universitet, Institutionen för datavetenskap. Linköpings universitet, Tekniska fakulteten.
    Eckerberg, Maria
    Linköpings universitet, Institutionen för datavetenskap. Linköpings universitet, Tekniska fakulteten.
    Klamer, Linda
    Linköpings universitet, Institutionen för datavetenskap. Linköpings universitet, Tekniska fakulteten.
    Ledin, Johanna
    Linköpings universitet, Institutionen för datavetenskap. Linköpings universitet, Tekniska fakulteten.
    Tarander, Jasmine
    Linköpings universitet, Institutionen för datavetenskap, Interaktiva och kognitiva system. Linköpings universitet, Tekniska fakulteten.
    Bång, Magnus
    Linköpings universitet, Institutionen för datavetenskap, Interaktiva och kognitiva system. Linköpings universitet, Tekniska fakulteten.
    Engine Failure Induced Task Load Transient for Simulation Based Certification Aiding for Aircraft2018Ingår i: ADVANCES IN HUMAN ASPECTS OF TRANSPORTATION, SPRINGER INTERNATIONAL PUBLISHING AG , 2018, Vol. 597, s. 79-86Konferensbidrag (Refereegranskat)
    Abstract [en]

    This study is one of a series of studies, researching various aspects that all aim at enhanced simulation based certification aiding for aircraft. An experimental within-group design study was performed with 10 participants ( 5 male, and 5 female). The results showed a significant difference, F(2,16) = 5.11, p = 0.019, in mental workload between an engine failure condition and an normal condition for eye blink frequency. No effect of speed at the engine failure event on mental workload was found.

  • 25.
    Allen, John
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Scania CV AB.
    A Method for Reducing Ash Volume in Wall-Flow Diesel Particulate Filters: Water Injection as a Service Tool to Improve Fuel Consumption and Particulate Filter Service Life2017Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
  • 26.
    Alm Grundström, Henrik
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanik och hållfasthetslära. Linköpings universitet, Tekniska fakulteten.
    Developments in Topology Optimization in the ADDMAN Project2018Rapport (Övrigt vetenskapligt)
    Abstract [en]

    This document gives an account of some of the work done so far on topology optimization (TO) in the ADDMAN project. As well as the mathematical formulations and implementations details, short discussions are presented on some of the nuances of the different formulations and how they should be used efficiently

  • 27.
    Alm Grundström, Henrik
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanik och hållfasthetslära.
    Topology Optimization for Additive Manufacturing Considering Stress and Anisotropy2017Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Additive manufacturing (AM) is a particularly useful manufacturing method for components designed using topology optimization (TO) since it allows for a greater part complexity than any traditional manufacturing method. However, the AM process potentially leads to anisotropic material properties due to the layer-by-layer buildup of parts and the fast and directional cooling. For Ti6Al4V tensile specimens built using electron beam melting (EBM), it has been observed that flat built specimens show superior strength and elastic moduli compared to top built specimens. Designs with the loading direction parallel to the build layers are therefore expected to show greater reliability.

    In this thesis a procedure is developed to optimize the AM build orientation considering anisotropic elastic material properties. A transversely isotropic material model is used to represent the in-plane and out-of-plane characteristics of AM produced parts. Two additional design variables are added to the TO formulation in order to control the orientation of the material using a coordinate transformation. Sensitivity analysis for the material direction variables is conducted for compliance as well as maximum von-Mises stress using a -norm stress aggregation function.

    The procedures for the AM build orientation optimization and stress constraints are implemented in the finite element software TRINITAS and evaluated using a number of examples in 2D and 3D. It is found that the procedure works well for compliance as well as stress but that a combination of these may lead to convergence issues due to contradicting optimal material orientations. An evaluation of the -norm stress aggregation function showed that a single global stress measure in combination with a stress correction procedure works well for most problems given that the mesh is refined enough to resolve the stresses accurately.  

  • 28.
    Alm, Torbjörn
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell arbetsvetenskap. Linköpings universitet, Tekniska högskolan.
    Simulator-Based Design: Methodology and vehicle display application2007Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Human-in-the-loop simulators have long been used in the research community as well as in industry. The aviation field has been the pioneers in the use of simulators for design purposes. In contrast, corresponding activities in the automotive area have been less widespread. Published reports on experimental activities based on human-in-the-loop simulations have focused on methods used in the study, but nobody seems to have taken a step back and looked at the wider methodological picture of Simulator-Based Design. The purpose of this thesis is to fill this gap by drawing, in part, upon the author’s long experience in this field.

    In aircraft and lately also in ground vehicles there has been a technology shift from pure mechanics to computer-based systems. The physical interface has turned into screen-based solutions. This trend towards glass has just begun for ground vehicles. This development in vehicle technology has opened the door for new design approaches, not only for design itself, but also for the development process. Simulator-Based Design (SBD) is very compatible with this trend. The first part of this thesis proposes a structure for the process of SBD and links it to the corresponding methodology for software design.

    In the second part of the thesis the focus changes from methodology to application and specifically to the design of three-dimensional situation displays. Such displays are supposed to support the human operator with a view of a situation beyond the more or less limited visual range. In the aircraft application interest focuses on the surrounding air traffic in the light of the evolving free-flight concept, where responsibility for separation between aircraft will be (partly) transferred from ground-based flight controllers to air crews. This new responsibility must be supported by new technology and the situational view must be displayed from the perspective of the aircraft. Some basic design questions for such 3D displays were investigated resulting in an adaptive interface approach, where the current situation and task govern the details of information presentation.

    The thesis also discusses work on situation displays for ground vehicles. The most prominent example may be the Night Vision system, where the road situation ahead is depicted on a screen in the cab. The existing systems are based on continuous presentation, an approach that we have questioned, since there is strong evidence for negative behavioral adaptation. This means, for example, that the driver will drive faster, since vision has been enhanced, and thereby consume the safety margins that the system was supposed to deliver. Our investigation supports a situation-dependant approach and no continuous presentation.

    In conclusion, the results from our simulator-based studies showed advantages for adaptive interface solutions. Such design concepts are much more complicated than traditional static interfaces. This finding emphasizes the need for more dynamic design resources in order to have a complete understanding of the situation-related interface changes. The use of human-in-the-loop simulators and deployment of Simulator-Based Design will satisfy this need.

  • 29.
    Alriksson, Maria
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling.
    Aronsson, Lina
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling.
    Cross-functional Co-operation for Improved Product Development: - a case study at Siemens Industrial Turbomachinery AB2007Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats
    Abstract [sv]

    Syftet med det här examensarbetet är att identifiera och analysera relevanta dimensioner av samarbete mellan produktion och konstruktion i samband med produktutveckling. Syftet är också att föreslå förbättringar i samarbetet mellan produktions- och konstruktionsavdelningarna i produktutvecklingsprocessen (PDP) på Siemens Industrial Turbomachinery AB (SIT AB). SIT AB producerar ång- och gasturbiner. Betydelsen av ett gott samarbete mellan avdelningar i organisationen har belysts i samband med att produktionstaken de senaste åren har ökat och fler produktutvecklingsprojekt har initierat.

    Vi har utvecklat en analysmodell som innehåller de dimensioner av samarbete som vi anser är relevanta för området. Dessa är: timing av uppströms – nedströms aktiviteter, rikhet & kvalitet på information, frekvens av informationsöverföring, riktning på kommunikation, formalisering av kommunikation, organisatoriskt support, måloptimering, attityder i tvärfunktionella team samt förståelse för uppgifter.

    Vid produktutveckling följer SIT AB den omfattande processen PDP. PDP är en sekventiell process där alla aktiviteter utförs i en sekvens vilket motverkar implementeringen av Concurrent Engineering. Concurrent Engineering syftar till att korta utvecklingstiden för produkter och beakta arbetet ur ett helhetsperspektiv bland annat genom utförande av oberoende aktiviteter parallellt. Därför anser vi att SIT AB ska arbeta mot en mer integrerad process med fler parallella aktiviteter.

    Det är stor skillnad på prestationen i samarbetsdimensionerna mellan stora och små projekt. Stora projekt fungerar mycket bättre än små vilket kan relateras till att stora projekt följer processbeskrivningarna bättre, har en bättre balans mellan informell och formell kommunikation, och fokuserar mer på projektmål och sammansvetsade projektgrupper. Förbättringsförslagen är presenterade som konkreta åtgärder i ett separat kapitel och är klassificerade med hänsyn till varje förslags potentiella effekt på organisationen och dess uppskattade svårighetsgrad att implementera. Förslagen är bland annat att utbilda fler projektledare, inrätta verkstadspraktik för konstruktörer och ge fler och bättre förklaringar till beslut och handlingar.

  • 30.
    Altrén, Jesper
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling.
    Lyth, Mattias
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling.
    Solvency II - A compliance burden or an opportunity for the Swedish non-life insurance industry?2007Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats
    Abstract [en]

    Insurance companies and banks are of great importance to the economy, which is why their stability must be ensured. In order to prevent bankruptcies in the financial sector, these companies are subject to strict regulations, which set standards for risk management and the amount of reserve capital required. Such capital reserves act as safety buffers to protect the customers from extraordinary events. In the insurance industry, the reserve capital is referred to as the solvency margin.

    Solvency II is new set of insurance regulations that aims to set a common standard regarding solvency capital and risk management for insurance companies within the European Union. The potential costs and benefits of the regulations are of importance not only to insurance companies but also to those firms that offer services and products to the insurance industry in the field of risk management. Solvency II is often compared to the Basel II accord for banks, which had a strong business case in the way that banks could significantly lower their reserve capital and use it for other purposes. The question is, however, whether insurance companies can expect similar benefits from Solvency II.

    The purpose of this study is therefore to explain how the Solvency II regulations will affect risk management in the Swedish non-life insurance industry, and whether these changes can result in opportunities for insurance companies. This is achieved by studying the new regulations and conducting a number of interviews with insurance company representatives as well as industry experts. Four potential effects of Solvency II have been investigated: capital levels, insurance pricing, credit ratings and reinsurance.

    The findings of the study indicate that no obvious benefits related to the potential effects above can be realised by complying with Solvency II. The future capital requirements will come close to those already enforced by supervisors today, resulting in a minor change that can go both ways. Neither credit ratings nor reinsurance covers seem to become notably affected by Solvency II. As for insurance pricing, an increasingly sophisticated risk-based allocation of the cost of solvency capital provides the most notable opportunity of Solvency II, but at present, no conclusions can be drawn regarding the effects of such changes. On the other hand, Solvency II will put pressure on improving systems to ensure the quality and traceability of data.

    Thus, the actual changes in risk management practices are not expected to be substantial among Swedish non-life insurance companies, and it therefore seems unlikely that insurance companies would be willing to invest as heavily in reaching Solvency II compliance as banks have done in Basel II.

  • 31.
    Amadori, Kristian
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska högskolan.
    Geometry Based Design Automation: Applied to Aircraft Modelling and Optimization2012Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Kraven på ökad effektivitet utmanar ständigt  produktutvecklingsprocessen. I och med att ingenjörsprodukter blir allt mer komplexa, växer genom hela utvecklingsprocessen behovet av verktyg och metoder för integrerad och automatiserad design. Multidisciplinär Design Optimering (MDO) är en lovande teknik som kan drastiskt förbättra parallell design. I ett MDO ramverk är flera disciplinära modeller sammankopplade för att uppnå ett holistiskt systemperspektiv, men där synergierna mellan olika delsystem också kan fångas upp. Bland alla möjliga discipliner spelar geometrimodellen en central roll, eftersom den innefattar en stor del av all information som är nödvändig för andra disciplinära analyser.

    I avhandlingen studeras ett flertal metoder för att möjliggöra multidisciplinär optimering i de tidigaste faserna av flygplansdesign. I synnerlighet är forskningen riktad mot att införa geometriska CAD modeller i designloopen. Det blir därmed nödvändigt att kunna automatiskt generera eller uppdatera geometriska modeller, vilket i avhandlingen kallas för ”geometribaserad design automation”.

    Avhandlingen förordar att Knowledge Based Engineering (KBE) tekniker används för att konstruktioner skall kunna automatiseras och återanvändas. Så kallade Hög Nivå CAD mallar (på engelska High Level CAD templates – HLCts) föreslås för att automatiskt generera och uppdatera geometrimodeller. HLCts kan jämföras med parametriska LEGO® klossar som innehåller variabler för design och analys. Mallarna kan samlas i bibliotek; därefter har konstruktörer eller dator agenter möjligheten att först topologiskt välja en mall och sedan ändra på dess utförande genom utvalda parametrar.

    Eftersom parameterisering är ett centralt begrepp för HLCt principen, föreslås även en fördjupad analys av ämnet. I stor del av MDO och KBE litteraturen ställs det två återkommande krav på geometrimodellen: modellen bör vara flexibel och robust. Eftersom dessa krav aldrig har getts en formell formulering, förordas i avhandlingen en matematisk beskrivning av modellrobusthet och - flexibilitet. Tack vore formuleringen är det möjligt att noggrant mäta och jämföra till vilken grad geometriska modeller fungerar.

    Slutligen presenteras en valideringsprocess baserad på kostnadseffektiva prototyper som används för att snabbt bekräfta analytiska resultat från MDO ramverket. Den föreslagna processen nyttjar olika tillverkningsmetoder, beroende på prototypens tänkta storlek och användning. I sista delen av avhandlingen presenteras även tre applikationsexempel, valda från forskningsprojekt som har bedrivits på Linköpings universitet och som visar hur de teoretiska resultaten har kommit till användning i praktiken.

    Delarbeten
    1. Automated Design and Fabrication of Micro Air Vehicles
    Öppna denna publikation i ny flik eller fönster >>Automated Design and Fabrication of Micro Air Vehicles
    2011 (Engelska)Ingår i: Journal of Aerospace Engineering, ISSN 0893-1321, E-ISSN 1943-5525, Vol. 226, nr 10, s. 1271-1282Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    A methodology for an automated design and fabrication of micro-air vehicles (MAVs) is presented. A design optimization framework has been developed that interfaces several software systems to generate MAVs to optimally fulfil specific mission requirements. By means of amulti-objective genetic algorithm, families of MAVs are tailored with respect to objectives such as weight and endurance. The framework takes into consideration the airframe and aerodynamic design as well as the selection and positioning of internal components. The selection of propulsion system components is made from a database of off-the-shelf components. In combination with a three-dimensional printer, physical prototypes can be quickly manufactured. A validation of the framework results from flight tests of a real MAV is also presented.

    Ort, förlag, år, upplaga, sidor
    SAGE Journals online, 2011
    Nyckelord
    Micro Air Vehicle; multidisciplinary optimization; multi-objective optimization; genetic algorithm; CAD automation; design automation
    Nationell ämneskategori
    Maskinteknik
    Identifikatorer
    urn:nbn:se:liu:diva-73107 (URN)10.1177/0954410011419612 (DOI)000312145300006 ()
    Tillgänglig från: 2011-12-16 Skapad: 2011-12-16 Senast uppdaterad: 2017-12-08Bibliografiskt granskad
    2. Flexible and Robust CAD Models for Design Automation
    Öppna denna publikation i ny flik eller fönster >>Flexible and Robust CAD Models for Design Automation
    2012 (Engelska)Ingår i: Advanced Engineering Informatics, ISSN 1474-0346, E-ISSN 1873-5320, Vol. 26, nr 2, s. 180-195Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    This paper explores novel methodologies for enabling Multidisciplinary Design Optimization (MDO) of complex engineering products. To realize MDO, Knowledge Based Engineering (KBE) is adopted with the aim of achieving design reuse and automation. The aim of the on-going research at Linköping University is to shift from manual modelling of disposable geometries to Computer Aided Design (CAD) automation by introducing generic high-level geometry templates. Instead of repeatedly modelling similar instances of objects, engineers should be able to create more general models that can represent entire classes of objects. The proposed methodology enables utilization of commercial design tools, hence taking industrial feasibility into consideration. High Level CAD templates (HLCt) will be proposed and discussed as the building blocks of flexible and robust CAD models, which in turn enables high-fidelity geometry in the MDO loop. Quantification of the terms flexibility and robustness is also presented, providing a means to measure the quality of the geometry models. Finally, application examples are presented in which the outlined framework is evaluated. The applications have been chosen from three ongoing research projects aimed at automating the design of transport aircraft, industrial robots, and micro air vehicles.

    Nyckelord
    Design automation, Multidisciplinary Design Optimization, Robustness, Flexibility, Knowledge-Based Engineering
    Nationell ämneskategori
    Maskinteknik
    Identifikatorer
    urn:nbn:se:liu:diva-73108 (URN)10.1016/j.aei.2012.01.004 (DOI)000308122400003 ()
    Tillgänglig från: 2011-12-16 Skapad: 2011-12-16 Senast uppdaterad: 2017-12-08Bibliografiskt granskad
    3. Development of a subscale flight testing platform for a generic future fighter
    Öppna denna publikation i ny flik eller fönster >>Development of a subscale flight testing platform for a generic future fighter
    2010 (Engelska)Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    One branch of the current research in aircraft design at Linköping University is focused on fast concept evaluation in early design stages. This covers multidisciplinary optimization using tools of different level of complexity and low-cost subscale flight testing. In some cases a flight test will provide more answers than several computations ever could. In order to achieve this goal a methodology is required to allow fast creation of subscale flying concepts and to obtain as much reliable information as possible from the tests. The methodology is currently being developed. One important part of it is the scaling methodology and the imposed requirements on manufacturing. The present paper presents the latest subscale demonstrator from Linköping University that has been built as part of the study initiated by the Swedish Material Board on a Generic Future Fighter aircraft.

    Nyckelord
    subscale, demonstrator, flight testing
    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-62594 (URN)
    Konferens
    27TH INTERNATIONAL CONGRESS OF THE AERONAUTICAL SCIENCES - ICAS 2010
    Tillgänglig från: 2011-11-10 Skapad: 2010-11-30 Senast uppdaterad: 2011-12-16Bibliografiskt granskad
    4. Evaluation of Automatically Designed Micro Air Vehicles and Flight Testing
    Öppna denna publikation i ny flik eller fönster >>Evaluation of Automatically Designed Micro Air Vehicles and Flight Testing
    2010 (Engelska)Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    The presented work is centered on the evaluation of Micro or Mini Air Vehicles (MAV) that have been automatically designed and manufactured. An in-house developed design framework uses several coupled computer software’s to generate the geometric design in CAD, a well as list of off the shelf components for the propulsion system, and computer code for autonomous flight ready to upload in the intended autopilot. The paper describes the experiences made so far regarding automation of the design process and of manufacturing. Furthermore, it presents results from evaluation and analysis of the optimization algorithm and flight testing, and from continuing work with the framework to achieve deeper understanding of the process and to fine-tune the design automation performance. The flight data is correlated to the predicted performances to validate the models and design process.

    Nyckelord
    Design automation, multidisciplinary optimization, MAV
    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-62584 (URN)
    Konferens
    48th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition, Orlando, Florida, Jan. 4-7, 2010
    Tillgänglig från: 2011-11-10 Skapad: 2010-11-30 Senast uppdaterad: 2011-12-16Bibliografiskt granskad
    5. Use of Panel Code Modeling in a Framework for Aircraft Concept Optimization
    Öppna denna publikation i ny flik eller fönster >>Use of Panel Code Modeling in a Framework for Aircraft Concept Optimization
    2006 (Engelska)Ingår i: 11th AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference, 6-8 September, Portsmouth, Virginia, USA, 2006, s. 7084-Konferensbidrag, Publicerat paper (Övrigt vetenskapligt)
    Abstract [en]

     

     

    In this study the use of a high-order panel code within a framework for aircraft concept design is discussed. The framework is intended to be a multidisciplinary optimization tool to be adopted from the very beginning of the conceptual design phase in order to define and refine the aircraft design, with respect to its aerodynamic, stability and control, structure and basic aircraft systems. The presented work is aimed at developing a module for aerodynamic analysis of concepts as a basis for a direct search optimization of the concept layout. The design criterion, used in the example presented here, is to minimize the maximum take-off weight required to fulfil the mission. Classic and simple equations are used together with the data generated by the panel code solver to calculate the aircraft’s performances. Weights are calculated by means of statistical group weight equations, but the weight could also be calculated from a CAD-model. The design of an Unmanned Combat Air Vehicle is used as test case for three different optimization algorithms: one gradient method based (Fmincon), one non-gradient based (Complex) and one Genetic Algorithm (GA). Comparison of results and performances shows that the Genetic Algorithm is best fitted for the specific problem, having the by far best hit rate, even if it is at a cost of longer computing time. The Complex algorithm requires less iterations and is also able to find the optimum solution, but with a worse hit rate, while Fmincon can not reach to a global optimum. The suggested optimized configuration for the aircraft is very similar to the Boeing X-45C and Northrop Grumman X-47B.

    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-13306 (URN)
    Tillgänglig från: 2011-11-10 Skapad: 2008-05-21 Senast uppdaterad: 2011-12-16Bibliografiskt granskad
  • 32.
    Amadori, Kristian
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska högskolan.
    Lundström, David
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Design Automation Framework for Micro Air Vehicles2009Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    At Linköping University work has been done to automate the design process of Micro or Mini Air Vehicles. A design optimization framework that links together a CAD system for airframe design and panel code for aerodynamic design has been developed. This paper describes the experience made so far, and demonstrates a case study on fully automated design where a 3D printer is used for manufacturing.

  • 33.
    Amadori, Kristian
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska högskolan.
    Lundström, David
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Krus, Petter
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Automated Design and Fabrication of Micro Air Vehicles2011Ingår i: Journal of Aerospace Engineering, ISSN 0893-1321, E-ISSN 1943-5525, Vol. 226, nr 10, s. 1271-1282Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A methodology for an automated design and fabrication of micro-air vehicles (MAVs) is presented. A design optimization framework has been developed that interfaces several software systems to generate MAVs to optimally fulfil specific mission requirements. By means of amulti-objective genetic algorithm, families of MAVs are tailored with respect to objectives such as weight and endurance. The framework takes into consideration the airframe and aerodynamic design as well as the selection and positioning of internal components. The selection of propulsion system components is made from a database of off-the-shelf components. In combination with a three-dimensional printer, physical prototypes can be quickly manufactured. A validation of the framework results from flight tests of a real MAV is also presented.

  • 34.
    Amadori, Kristian
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska högskolan.
    Melin, Tomas
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Staack, Ingo
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Krus, Petter
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Multidisciplinary Optimization of Wing Structure Using Parametric Models2013Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Aircraft design is an inherently multidisciplinary activity that requires integrating different models and tools to reach a well-balanced and optimized product. At Linköping University a design framework is being developed to support the initial design space exploration and the conceptual design phase. Main characteristics of the framework are its flexible database in XML format, together with close integration of automated CAD and other tools, which allows the developed geometry to be directly used in the subsequent preliminary design phase. In particular, the aim of the proposed work is to test the framework by designing, optimizing and studying a transport aircraft wing with respect to aerodynamic, geometry, structural and accessability constraints. The project will provide an initial assessment of the capability of the framework, both in terms of processing speed and accuracy of the results.

  • 35.
    Amadori, Kristian
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska högskolan.
    Tarkian, Mehdi
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska högskolan.
    Ölvander, Johan
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska högskolan.
    Krus, Petter
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Flexible and Robust CAD Models for Design Automation2012Ingår i: Advanced Engineering Informatics, ISSN 1474-0346, E-ISSN 1873-5320, Vol. 26, nr 2, s. 180-195Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper explores novel methodologies for enabling Multidisciplinary Design Optimization (MDO) of complex engineering products. To realize MDO, Knowledge Based Engineering (KBE) is adopted with the aim of achieving design reuse and automation. The aim of the on-going research at Linköping University is to shift from manual modelling of disposable geometries to Computer Aided Design (CAD) automation by introducing generic high-level geometry templates. Instead of repeatedly modelling similar instances of objects, engineers should be able to create more general models that can represent entire classes of objects. The proposed methodology enables utilization of commercial design tools, hence taking industrial feasibility into consideration. High Level CAD templates (HLCt) will be proposed and discussed as the building blocks of flexible and robust CAD models, which in turn enables high-fidelity geometry in the MDO loop. Quantification of the terms flexibility and robustness is also presented, providing a means to measure the quality of the geometry models. Finally, application examples are presented in which the outlined framework is evaluated. The applications have been chosen from three ongoing research projects aimed at automating the design of transport aircraft, industrial robots, and micro air vehicles.

  • 36.
    Amankwah-Amoah, Joseph
    et al.
    Kent Business School, University of Kent, UK.
    Sjögren, Hans
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Nationalekonomi. Linköpings universitet, Filosofiska fakulteten.
    Ottosson, Jan
    Department of Economic History, Uppsala University, Uppsala, Sweden.
    United We Stand, Divided We Fall.: Historical Trajectory of Strategic Renewal Activities at Scandinavian Airlines System, 1946-2012.2017Ingår i: Business History, ISSN 0007-6791, E-ISSN 1743-7938, Vol. 59, nr 4, s. 572-606Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Although the second half of the twentieth century saw the rise and fall of ‘multi-flag companies’ (MFCs) in the civil aviation industry, our understanding of how some managed to buck the trend and achieve longevity remains limited. This article advances business history and strategic management research by examining the strategic renewal activities of Scandinavian Airlines (formerly Scandinavian Airlines System [SAS]) during the period 1946–2012. The study sheds light on the key roles of private and state owners, rivals as well as banks, in critical financial phases are discussed in terms of longevity in the company. The longevity of the business stems from the leaders’ ability to develop as anticipated and respond to change in their competitive arena in close interaction with the owners. Thus, incumbent firms that strategically renew themselves prior to or during market reform, such as deregulation, enhance their chances of developing the size of their networks and revenue streams. Our main contribution to business history and strategic management literatures is the development of context-specific stages, which shed light on the evolution of strategic renewal activities and shifts from older processes and routines towards customer service and efficiency.

  • 37.
    Andersson, Anders
    Linköpings universitet, Institutionen för datavetenskap. Linköpings universitet, Tekniska fakulteten. Statens väg- och transportforskningsinstitut (VTI), Trafik och trafikant,TRAF, Fordonsteknik och simulering, FTS, Linköping, Sweden.
    Distributed Moving Base Driving Simulators: Technology, Performance, and Requirements2019Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Development of new functionality and smart systems for different types of vehicles is accelerating with the advent of new emerging technologies such as connected and autonomous vehicles. To ensure that these new systems and functions work as intended, flexible and credible evaluation tools are necessary. One example of this type of tool is a driving simulator, which can be used for testing new and existing vehicle concepts and driver support systems. When a driver in a driving simulator operates it in the same way as they would in actual traffic, you get a realistic evaluation of what you want to investigate. Two advantages of a driving simulator are (1.) that you can repeat the same situation several times over a short period of time, and (2.) you can study driver reactions during dangerous situations that could result in serious injuries if they occurred in the real world. An important component of a driving simulator is the vehicle model, i.e., the model that describes how the vehicle reacts to its surroundings and driver inputs. To increase the simulator realism or the computational performance, it is possible to divide the vehicle model into subsystems that run on different computers that are connected in a network. A subsystem can also be replaced with hardware using so-called hardware-in-the-loop simulation, and can then be connected to the rest of the vehicle model using a specified interface. The technique of dividing a model into smaller subsystems running on separate nodes that communicate through a network is called distributed simulation.

    This thesis investigates if and how a distributed simulator design might facilitate the maintenance and new development required for a driving simulator to be able to keep up with the increasing pace of vehicle development. For this purpose, three different distributed simulator solutions have been designed, built, and analyzed with the aim of constructing distributed simulators, including external hardware, where the simulation achieves the same degree of realism as with a traditional driving simulator. One of these simulator solutions has been used to create a parameterized powertrain model that can be configured to represent any of a number of different vehicles. Furthermore, the driver's driving task is combined with the powertrain model to monitor deviations. After the powertrain model was created, subsystems from a simulator solution and the powertrain model have been transferred to a Modelica environment. The goal is to create a framework for requirement testing that guarantees sufficient realism, also for a distributed driving simulation.

    The results show that the distributed simulators we have developed work well overall with satisfactory performance. It is important to manage the vehicle model and how it is connected to a distributed system. In the distributed driveline simulator setup, the network delays were so small that they could be ignored, i.e., they did not affect the driving experience. However, if one gradually increases the delays, a driver in the distributed simulator will change his/her behavior. The impact of communication latency on a distributed simulator also depends on the simulator application, where different usages of the simulator, i.e., different simulator studies, will have different demands. We believe that many simulator studies could be performed using a distributed setup. One issue is how modifications to the system affect the vehicle model and the desired behavior. This leads to the need for methodology for managing model requirements. In order to detect model deviations in the simulator environment, a monitoring aid has been implemented to help notify test managers when a model behaves strangely or is driven outside of its validated region. Since the availability of distributed laboratory equipment can be limited, the possibility of using Modelica (which is an equation-based and object-oriented programming language) for simulating subsystems is also examined. Implementation of the model in Modelica has also been extended with requirements management, and in this work a framework is proposed for automatically evaluating the model in a tool.

    Delarbeten
    1. Vehicle Powertrain Test Bench Co-Simulation with a Moving Base Simulator Using a Pedal Robot
    Öppna denna publikation i ny flik eller fönster >>Vehicle Powertrain Test Bench Co-Simulation with a Moving Base Simulator Using a Pedal Robot
    2013 (Engelska)Ingår i: SAE International Journal of Passenger Cars - Electronic and Electrical Systems, ISSN 1946-4614, E-ISSN 1946-4622, Vol. 6, nr 1, s. 169-179Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    To evaluate driver perception of a vehicle powertrain a moving base simulator is a well-established technique. We are connecting the moving base simulator Sim III, at the Swedish National Road and Transport Research Institute with a newly built chassis dynamometer at Vehicular Systems, Linköping University. The purpose of the effort is to enhance fidelity of moving base simulators by letting drivers experience an actual powertrain. At the same time technicians are given a new tool for evaluating powertrain solutions in a controlled environment. As a first step the vehicle model from the chassis dynamometer system has been implemented in Sim III. Interfacing software was developed and an optical fiber covering the physical distance of 500 m between the facilities is used to connect the systems. Further, a pedal robot has been developed that uses two linear actuators pressing the accelerator and brake pedals. The pedal robot uses feedback loops on accelerator position or brake cylinder pressure and is controlled via an UDP interface. Results from running the complete setup showed expected functionality and we are successful in performing a driving mission based on real road topography data. Vehicle acceleration and general driving feel was perceived as realistic by the test subjects while braking still needs improvements. The pedal robot construction enables use of a large set of cars available on the market and except for mounting the brake pressure sensor the time to switch vehicle is approximately 30 minutes.

    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-92215 (URN)10.4271/2013-01-0410 (DOI)
    Tillgänglig från: 2013-05-08 Skapad: 2013-05-08 Senast uppdaterad: 2019-04-28Bibliografiskt granskad
    2. A Driving Simulation Platform using Distributed Vehicle Simulators and HLA
    Öppna denna publikation i ny flik eller fönster >>A Driving Simulation Platform using Distributed Vehicle Simulators and HLA
    Visa övriga...
    2015 (Engelska)Ingår i: Proceedings of the DSC 2015 Europe: Driving Simulation Conference & Exhibition / [ed] Heinrich Bülthoff, Andras Kemeny and Paolo Pretto, 2015, s. 123-130Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    Modern vehicles are complex systems consisting of an increasing large multitude of components that operate together. While functional verification on individual components is important, it is also important to test components within a driving environment, both from a functional perspective and from a driver perspective. One proven way for testing is vehicle simulators and in this work the main goals have been to increase flexibility and scalability by introducing a distributed driving simulator platform.

    As an example, consider a workflow where a developer can go from a desktop simulation to an intermediate driving simulator to a high fidelity driving simulator with Hardware-In-the-Loop systems close to a finished vehicle in an easy way. To accomplish this, a distributed simulation architecture was designed and implemented that divides a driving simulator environment into four major entities with well-defined interfaces, using HLA as the method of communication. This platform was evaluated on two aspects, flexibility/scalability and timing performance. Results show that increased flexibility and scalability was achieved when using a distributed simulation platform. It is also shown that latency was only slightly increased when using HLA.

    Nyckelord
    Test, Vehicle, Engine, Performance, Simulator (driving), Computer
    Nationell ämneskategori
    Datorsystem
    Forskningsämne
    90 Road: Vehicles and vehicle technology, 911 Road: Components of the vehicle; 90 Road: Vehicles and vehicle technology, 96 Road: Vehicle operating and management
    Identifikatorer
    urn:nbn:se:liu:diva-136153 (URN)9783981309935 (ISBN)
    Konferens
    Driving Simulation Conference 2015. 16-18 september 2015, Tübingen, Germany
    Tillgänglig från: 2016-01-11 Skapad: 2017-03-31 Senast uppdaterad: 2019-04-28Bibliografiskt granskad
    3. Testing cooperative intelligent transport systems in distributed simulators
    Öppna denna publikation i ny flik eller fönster >>Testing cooperative intelligent transport systems in distributed simulators
    Visa övriga...
    2019 (Engelska)Ingår i: Transportation Research Part F: Traffic Psychology and Behaviour, ISSN 1369-8478, E-ISSN 1873-5517, Vol. 65, s. 206-216Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Simulation is often used as a technique to test and evaluate systems, as it provides a cost-efficient and safe alternative for testing and evaluation. A combination of simulators can be used to create high-fidelity and realistic test scenarios, especially when the systems-under-test are complex. An example of such complex systems is Cooperative Intelligent Transport Systems (C-ITS), which include many actors that are connected to each other via wireless communication in order to interact and cooperate. The majority of the actors in the systems are vehicles equipped with wireless communication modules, which can range from fully autonomous vehicles to manually driven vehicles. In order to test and evaluate C-ITS, this paper presents a distributed simulation framework that consists of (a) a moving base driving simulator; (b) a real-time vehicle simulator; and (c) network and traffic simulators. We present our approach for connecting and co-simulating the simulators. We report on limitation and performance that this simulation framework can achieve. Lastly, we discuss potential benefits and feasibility of using the simulation framework for testing of C-ITS.

    Ort, förlag, år, upplaga, sidor
    Elsevier, 2019
    Nyckelord
    Cooperative intelligent transportation systems, Hardware-in-the-loop, Network simulator, Traffic simulator, Moving base driving simulator
    Nationell ämneskategori
    Farkostteknik Datorsystem
    Identifikatorer
    urn:nbn:se:liu:diva-159824 (URN)10.1016/j.trf.2019.07.020 (DOI)
    Tillgänglig från: 2019-08-22 Skapad: 2019-08-22 Senast uppdaterad: 2019-08-22Bibliografiskt granskad
    4. Parameterization procedure of a powertrain model for a driving simulator
    Öppna denna publikation i ny flik eller fönster >>Parameterization procedure of a powertrain model for a driving simulator
    2016 (Engelska)Ingår i: Advances in Transportation Studies, ISSN 1824-5463, Vol. 1, s. 99-112Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    The automotive industry is facing a major challenge to reduce environmental impacts. As a consequence, the increasing diversity of powertrain configurations put a demand on testing and evaluation procedures. One of the key tools for this purpose is simulators. In this paper a powertrain model and a procedure for parameterizing it, using chassis dynamometers and a developed pedal robot are presented. The parameterizing procedure uses the on-board diagnostics of the car and does not require any additional invasive sensors.

    Thus, the developed powertrain model and parameterization procedure provide a rapid non- invasive way of modelling powertrains of test cars. The parameterizing procedure has been used to model a front wheel drive Golf V with a 1.4L multi-fuel engine and a manual gearbox. The achieved results show a good match between simulation results and test data. The powertrain model has also been tested in real-time in a driving simulator.

    Ort, förlag, år, upplaga, sidor
    Aracne editrice, 2016
    Nyckelord
    Motor, Test, Characteristics, Simulation
    Nationell ämneskategori
    Farkostteknik
    Forskningsämne
    90 Road: Vehicles and vehicle technology, 911 Road: Components of the vehicle
    Identifikatorer
    urn:nbn:se:liu:diva-156538 (URN)10.4399/978885489179109 (DOI)2-s2.0-84982994768 (Scopus ID)
    Tillgänglig från: 2019-04-26 Skapad: 2019-04-26 Senast uppdaterad: 2019-05-03Bibliografiskt granskad
    5. Vehicle model quality framework for moving base driving simulators, a powertrain model example
    Öppna denna publikation i ny flik eller fönster >>Vehicle model quality framework for moving base driving simulators, a powertrain model example
    2018 (Engelska)Ingår i: International Journal of Vehicle Systems Modelling and Testing, ISSN 1745-6436, E-ISSN 1745-6444, Vol. 13, nr 2, s. 93-108Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Moving base driving simulators, with an enclosed human driver, are often used to study driver-vehicle interaction or driver behaviour. Reliable results from such a driving simulator study strongly depend on the perceived realism by the driver in the performed driving task. Assuring sufficient fidelity for a vehicle dynamics model during a driving task is currently to a large degree a manual task. Focus here is to automate this process by employing a framework using collected driving data for detection of model quality for different driving tasks. Using this framework, a powertrain model credibility is predicted and assessed. Results show that chosen powertrain model is accurate enough for a driving scenario on rural roads/motorway, but need improvements for city driving. This was expected, considering the complexity of the vehicle dynamics model, and it was accurately captured by the proposed framework which includes real-time information to the simulator operator.

    Ort, förlag, år, upplaga, sidor
    InderScience Publishers, 2018
    Nyckelord
    vehicle dynamics model, driving simulator, driving task, quality framework, domain of validity, domain of operation, powertrain model
    Nationell ämneskategori
    Datorsystem Farkostteknik
    Identifikatorer
    urn:nbn:se:liu:diva-156544 (URN)10.1504/IJVSMT.2018.098330 (DOI)2-s2.0-85063100727 (Scopus ID)
    Tillgänglig från: 2019-04-26 Skapad: 2019-04-26 Senast uppdaterad: 2019-05-03Bibliografiskt granskad
    6. Models for Distributed Real-Time Simulation in a Vehicle Co-Simulator Setup
    Öppna denna publikation i ny flik eller fönster >>Models for Distributed Real-Time Simulation in a Vehicle Co-Simulator Setup
    2013 (Engelska)Ingår i: Proceedings of the 5th International Workshop on Equation-Based Object-Oriented Modeling Languages and Tools; April 19, University of Nottingham, Nottingham, UK / [ed] Henrik Nilsson, Linköping: Linköping University Electronic Press, 2013, Vol. 84, s. 131-139Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    A car model in Modelica has been developed to be used in a new setup for distributed real-time simulation where a moving base car simulator is connected with a real car in a chassis dynamometer via a 500m fiber optic communication link. The new co-simulator set-up can be used in a number of configurations where hardware in the loop can be interchanged with software in the loop. The models presented in this paper are the basic blocks chosen for modeling the system in the context of a distributed real-time simulation; estimating parameters for the powertrain model; the choice of numeric solver; and the interaction with the solver for real-time properties.

    Ort, förlag, år, upplaga, sidor
    Linköping: Linköping University Electronic Press, 2013
    Serie
    Linköping Electronic Conference Proceedings, ISSN 1650-3686, E-ISSN 1650-3740 ; 84
    Nyckelord
    Modelica; real-time; distributed; communications link
    Nationell ämneskategori
    Datorsystem
    Identifikatorer
    urn:nbn:se:liu:diva-118994 (URN)978-91-7519-621-3 (ISBN)978-91-7519-617-6 (ISBN)
    Konferens
    The 5th International Workshop on Equation-Based Object-Oriented Modeling Languages and Tools, April 19, University of Nottingham, Nottingham; UK
    Tillgänglig från: 2015-06-05 Skapad: 2015-06-05 Senast uppdaterad: 2019-04-28Bibliografiskt granskad
    7. Powertrain Model Assessment for Different Driving Tasks through Requirement Verification
    Öppna denna publikation i ny flik eller fönster >>Powertrain Model Assessment for Different Driving Tasks through Requirement Verification
    2018 (Engelska)Ingår i: The 9th EUROSIM Congress on Modelica and Simulation, 2018, s. 721-727Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    For assessing whether a system model is a good candidate for a particular simulation scenario or choosing the best system model between multiple design alternatives it is important to be able to evaluate the suitability of the system model. In this paper we present a methodology based on finite state machine requirements verifying system behaviour in a Modelica environment where the intended system model usage is within a moving base driving simulator. A use case illustrate the methodology with a Modelica powertrain system model using replaceable components and measured data from a Golf V. The achieved results show the importance of context of requirements and how users are assisted in finding system model issues. 

    Serie
    Linköping Electronic Conference Proceedings, ISSN 1650-3686, E-ISSN 1650-3740 ; 142
    Nyckelord
    system model assessment, requirement modelling, Modelica, finite state machine, powertrain validations
    Nationell ämneskategori
    Datorsystem
    Identifikatorer
    urn:nbn:se:liu:diva-156540 (URN)10.3384/ecp17142721 (DOI)978-91-7685-399-3 (ISBN)
    Konferens
    EUROSIM 2016
    Tillgänglig från: 2019-04-26 Skapad: 2019-04-26 Senast uppdaterad: 2019-05-13
  • 38.
    Andersson, Anders
    Linköpings universitet, Institutionen för datavetenskap. Linköpings universitet, Tekniska fakulteten. Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Extensions for Distributed Moving Base Driving Simulators2017Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Modern vehicles are complex systems. Different design stages for such a complex system include evaluation using models and submodels, hardware-in-the-loop systems and complete vehicles. Once a vehicle is delivered to the market evaluation continues by the public. One kind of tool that can be used during many stages of a vehicle lifecycle is driving simulators.

    The use of driving simulators with a human driver is commonly focused on driver behavior. In a high fidelity moving base driving simulator it is possible to provide realistic and repetitive driving situations using distinctive features such as: physical modelling of driven vehicle, a moving base, a physical cabin interface and an audio and visual representation of the driving environment. A desired but difficult goal to achieve using a moving base driving simulator is to have behavioral validity. In other words, \A driver in a moving base driving simulator should have the same driving behavior as he or she would have during the same driving task in a real vehicle.".

    In this thesis the focus is on high fidelity moving base driving simulators. The main target is to improve the behavior validity or to maintain behavior validity while adding complexity to the simulator. One main assumption in this thesis is that systems closer to the final product provide better accuracy and are perceived better if properly integrated. Thus, the approach in this thesis is to try to ease incorporation of such systems using combinations of the methods hardware-in-the-loop and distributed simulation. Hardware-in-the-loop is a method where hardware is interfaced into a software controlled environment/simulation. Distributed simulation is a method where parts of a simulation at physically different locations are connected together. For some simulator laboratories distributed simulation is the only feasible option since some hardware cannot be moved in an easy way.

    Results presented in this thesis show that a complete vehicle or hardware-in-the-loop test laboratory can successfully be connected to a moving base driving simulator. Further, it is demonstrated that using a framework for distributed simulation eases communication and integration due to standardized interfaces. One identified potential problem is complexity in interface wrappers when integrating hardware-in-the-loop in a distributed simulation framework. From this aspect, it is important to consider the model design and the intersections between software and hardware models. Another important issue discussed is the increased delay in overhead time when using a framework for distributed simulation.

    Delarbeten
    1. Vehicle Powertrain Test Bench Co-Simulation with a Moving Base Simulator Using a Pedal Robot
    Öppna denna publikation i ny flik eller fönster >>Vehicle Powertrain Test Bench Co-Simulation with a Moving Base Simulator Using a Pedal Robot
    2013 (Engelska)Ingår i: SAE International Journal of Passenger Cars - Electronic and Electrical Systems, ISSN 1946-4614, E-ISSN 1946-4622, Vol. 6, nr 1, s. 169-179Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    To evaluate driver perception of a vehicle powertrain a moving base simulator is a well-established technique. We are connecting the moving base simulator Sim III, at the Swedish National Road and Transport Research Institute with a newly built chassis dynamometer at Vehicular Systems, Linköping University. The purpose of the effort is to enhance fidelity of moving base simulators by letting drivers experience an actual powertrain. At the same time technicians are given a new tool for evaluating powertrain solutions in a controlled environment. As a first step the vehicle model from the chassis dynamometer system has been implemented in Sim III. Interfacing software was developed and an optical fiber covering the physical distance of 500 m between the facilities is used to connect the systems. Further, a pedal robot has been developed that uses two linear actuators pressing the accelerator and brake pedals. The pedal robot uses feedback loops on accelerator position or brake cylinder pressure and is controlled via an UDP interface. Results from running the complete setup showed expected functionality and we are successful in performing a driving mission based on real road topography data. Vehicle acceleration and general driving feel was perceived as realistic by the test subjects while braking still needs improvements. The pedal robot construction enables use of a large set of cars available on the market and except for mounting the brake pressure sensor the time to switch vehicle is approximately 30 minutes.

    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-92215 (URN)10.4271/2013-01-0410 (DOI)
    Tillgänglig från: 2013-05-08 Skapad: 2013-05-08 Senast uppdaterad: 2019-04-28Bibliografiskt granskad
    2. Models for Distributed Real-Time Simulation in a Vehicle Co-Simulator Setup
    Öppna denna publikation i ny flik eller fönster >>Models for Distributed Real-Time Simulation in a Vehicle Co-Simulator Setup
    2013 (Engelska)Ingår i: Proceedings of the 5th International Workshop on Equation-Based Object-Oriented Modeling Languages and Tools; April 19, University of Nottingham, Nottingham, UK / [ed] Henrik Nilsson, Linköping: Linköping University Electronic Press, 2013, Vol. 84, s. 131-139Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    A car model in Modelica has been developed to be used in a new setup for distributed real-time simulation where a moving base car simulator is connected with a real car in a chassis dynamometer via a 500m fiber optic communication link. The new co-simulator set-up can be used in a number of configurations where hardware in the loop can be interchanged with software in the loop. The models presented in this paper are the basic blocks chosen for modeling the system in the context of a distributed real-time simulation; estimating parameters for the powertrain model; the choice of numeric solver; and the interaction with the solver for real-time properties.

    Ort, förlag, år, upplaga, sidor
    Linköping: Linköping University Electronic Press, 2013
    Serie
    Linköping Electronic Conference Proceedings, ISSN 1650-3686, E-ISSN 1650-3740 ; 84
    Nyckelord
    Modelica; real-time; distributed; communications link
    Nationell ämneskategori
    Datorsystem
    Identifikatorer
    urn:nbn:se:liu:diva-118994 (URN)978-91-7519-621-3 (ISBN)978-91-7519-617-6 (ISBN)
    Konferens
    The 5th International Workshop on Equation-Based Object-Oriented Modeling Languages and Tools, April 19, University of Nottingham, Nottingham; UK
    Tillgänglig från: 2015-06-05 Skapad: 2015-06-05 Senast uppdaterad: 2019-04-28Bibliografiskt granskad
    3. A Driving Simulation Platform using Distributed Vehicle Simulators and HLA
    Öppna denna publikation i ny flik eller fönster >>A Driving Simulation Platform using Distributed Vehicle Simulators and HLA
    Visa övriga...
    2015 (Engelska)Ingår i: Proceedings of the DSC 2015 Europe: Driving Simulation Conference & Exhibition / [ed] Heinrich Bülthoff, Andras Kemeny and Paolo Pretto, 2015, s. 123-130Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    Modern vehicles are complex systems consisting of an increasing large multitude of components that operate together. While functional verification on individual components is important, it is also important to test components within a driving environment, both from a functional perspective and from a driver perspective. One proven way for testing is vehicle simulators and in this work the main goals have been to increase flexibility and scalability by introducing a distributed driving simulator platform.

    As an example, consider a workflow where a developer can go from a desktop simulation to an intermediate driving simulator to a high fidelity driving simulator with Hardware-In-the-Loop systems close to a finished vehicle in an easy way. To accomplish this, a distributed simulation architecture was designed and implemented that divides a driving simulator environment into four major entities with well-defined interfaces, using HLA as the method of communication. This platform was evaluated on two aspects, flexibility/scalability and timing performance. Results show that increased flexibility and scalability was achieved when using a distributed simulation platform. It is also shown that latency was only slightly increased when using HLA.

    Nyckelord
    Test, Vehicle, Engine, Performance, Simulator (driving), Computer
    Nationell ämneskategori
    Datorsystem
    Forskningsämne
    90 Road: Vehicles and vehicle technology, 911 Road: Components of the vehicle; 90 Road: Vehicles and vehicle technology, 96 Road: Vehicle operating and management
    Identifikatorer
    urn:nbn:se:liu:diva-136153 (URN)9783981309935 (ISBN)
    Konferens
    Driving Simulation Conference 2015. 16-18 september 2015, Tübingen, Germany
    Tillgänglig från: 2016-01-11 Skapad: 2017-03-31 Senast uppdaterad: 2019-04-28Bibliografiskt granskad
  • 39.
    Andersson, Anders
    et al.
    VTI, Swedish National Road and Transport Research Institute, Linköping, Sweden.
    Kharrazi, Sogol
    VTI, Swedish National Road and Transport Research Institute, Linköping, Sweden.
    Vehicle model quality framework for moving base driving simulators, a powertrain model example2018Ingår i: International Journal of Vehicle Systems Modelling and Testing, ISSN 1745-6436, E-ISSN 1745-6444, Vol. 13, nr 2, s. 93-108Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Moving base driving simulators, with an enclosed human driver, are often used to study driver-vehicle interaction or driver behaviour. Reliable results from such a driving simulator study strongly depend on the perceived realism by the driver in the performed driving task. Assuring sufficient fidelity for a vehicle dynamics model during a driving task is currently to a large degree a manual task. Focus here is to automate this process by employing a framework using collected driving data for detection of model quality for different driving tasks. Using this framework, a powertrain model credibility is predicted and assessed. Results show that chosen powertrain model is accurate enough for a driving scenario on rural roads/motorway, but need improvements for city driving. This was expected, considering the complexity of the vehicle dynamics model, and it was accurately captured by the proposed framework which includes real-time information to the simulator operator.

  • 40.
    Andersson, Anders
    et al.
    Statens väg- och transportforskningsinstitut, Fordonsteknik och simulering, FTS, Linköping, Sweden.
    Kharrazi, Sogol
    Statens väg- och transportforskningsinstitut, Fordonsteknik och simulering, FTS, Linköping, Sweden.
    Lind, Simon
    Statens väg- och transportforskningsinstitut, Fordonsteknik och simulering, FTS, Linköping, Sweden.
    Myklebust, Andreas
    Linköpings universitet, Institutionen för systemteknik, Fordonssystem. Linköpings universitet, Tekniska högskolan.
    Parameterization procedure of a powertrain model for a driving simulator2016Ingår i: Advances in Transportation Studies, ISSN 1824-5463, Vol. 1, s. 99-112Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The automotive industry is facing a major challenge to reduce environmental impacts. As a consequence, the increasing diversity of powertrain configurations put a demand on testing and evaluation procedures. One of the key tools for this purpose is simulators. In this paper a powertrain model and a procedure for parameterizing it, using chassis dynamometers and a developed pedal robot are presented. The parameterizing procedure uses the on-board diagnostics of the car and does not require any additional invasive sensors.

    Thus, the developed powertrain model and parameterization procedure provide a rapid non- invasive way of modelling powertrains of test cars. The parameterizing procedure has been used to model a front wheel drive Golf V with a 1.4L multi-fuel engine and a manual gearbox. The achieved results show a good match between simulation results and test data. The powertrain model has also been tested in real-time in a driving simulator.

  • 41.
    Andersson, Andreas
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling.
    Cell för induktionshärdning: -En inledande studie för ett beslutsunderlag2008Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats
    Abstract [sv]

    Detta arbete är ett examensarbete utfört av en student vid civilingenjörsprogrammet i maskinteknik vid Linköpings tekniska högskola och omfattar 30 högskolepoäng enligt nya europeiska systemet. Examensarbetet är utfört vid företaget AB Wahlquists Verkstäder i Linköping. Vilket är en koncern inom verkstadsindustrin med cirka 180 anställda och har anläggningar i både Sverige och Estland.

    Genom insamling av fakta från både litteratur, muntliga källor och genom studiebesök på anläggningar har en kortare sammanställning om tekniken för induktionshärdning utförts. Sammanställningen behandlar hur tekniken går till, hur den används, vilka begränsningar som finns samt hur utrustningen fungerar. Utformandet är styrt och prioriterat efter vad som för företaget är intressant och valt att ligga till grund för den inledande vetskapen om tekniken.

    Den underliggande fakta som presenterats har därefter varit underlag för de diskussioner och idéer som presenterats i form av förslag på utformning av en induktionshärdningscell. Där förslaget på den utformade cellen är efter de önskemål som företaget valt att ställa. För att sedan kunna göra förslaget tydligare för företaget har beräkningar för investeringskostnader, tider i produktion och beläggningsgrad med aktuella detaljer utförts.

    De för AB Wahlquists Verkstäder viktiga punkter, som kan vara av vikt att diskutera i form av synergieffekter till en anskaffning av induktionshärdningsutrustning har presenterats. Punkterna är av stort värde eller har mindre påverkan beroende på hur det specifika företaget själva väljer att behandla dessa. Däremot rekommenderas i arbetet att personer med rätt kunskaper avfärdar eller belyser de presenterade punkterna.

    Det genomförda arbetet har sedan sammanställts och en slutgiltig rekommendation har utfärdats till företaget. Här ges en rekommendation till hur företaget ska gå vidare med sitt arbete för den aktuella anskaffningen och vad som behöver studeras ytterligare innan ett komplett beslutsunderlag kan utfärdas.

  • 42.
    Andersson, Anna
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling.
    Wallin, Åsa
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling.
    Modularised Passenger Seats2007Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats
    Abstract [en]

    The purpose with this master’s thesis, with Scania CV AB in Södertälje as job initiator, has been to develop three different passenger seat concepts with focus on modularisation, functionality and production. The different concepts are: a foldable passenger seat, which is possible to fold away completely, a bench for two passengers, and a resting seat for resting during breaks when the vehicle is parked.

    The main tools used during the search for concept solutions have been brainstorming, morphological analyses, and evaluation matrixes. Prototypes have been made in order to visualise the ideas but also for the possibility to test them in a real truck cabin and by that find advantages but also flaws. Final product specifications has been made and with that guidelines for a continued development work.

    Experiences gained during this thesis work has been that by using ergonomic data and theories, well thought through designs, and standardised interfaces a good result can be achieved, which fulfils the demands and wishes placed on the future product.

  • 43.
    Andersson, Ann-Christine
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Kvalitetsteknik. Linköpings universitet, Tekniska högskolan.
    Olheden, Anna
    Landstinget i Kalmar län.
    Patient participation in quality improvement: managers’ opinions of patients as resources2012Ingår i: Journal of Clinical Nursing, ISSN 0962-1067, E-ISSN 1365-2702, Vol. 21, nr 23-24, s. 3590-3593Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this study was to investigate managers’ opinions of how to take advantage of patients as resources in quality improvement work in the Swedish healthcare sector.

  • 44.
    Andersson, Dennis
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Kvalitetsteknik. Linköpings universitet, Tekniska högskolan.
    Andersson, Victor
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Kvalitetsteknik. Linköpings universitet, Tekniska högskolan.
    Industrin och SPS: Möjligheter utifrån människa, teknik och organisation2012Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Detta examensarbete utförs i samarbete med företaget Järn AB, vilket är ett svenskt företag med gjuteri, pulvermetallurgi samt bearbetningsverksamhet. Produkterna är av varierande typ, storlek och volym, avsedd för ett brett kundsegment däribland fordonsindustrin samt maskintillverkare. Företaget har mer än 500 anställda och namnet Järn AB är fiktivt.

    Syftet med arbetet är att föreslå ett angreppssätt för hur Järn AB kan gå vidare med statistisk processtyrning (SPS). Detta angreppssätt ska baseras på erfarenheter från fordonsindustrin samt litteraturstudier. Studien kommer grunda sig utifrån perspektiven människa, teknik och organisation. Resultatet kommer även utmynna i ett praktiskt förslag som ger företaget konkreta exempel kring införandet av SPS.

    Förslagen i studien kommer grunda sig på fyra studiebesök som valts ut under arbetets gång. Tre av de valda företagen är framstående i kvalitetsfrågor inom svensk industri och det fjärde företaget jobbar med statistisk processtyrning i stor utsträckning. De besökta företagen har olika typer av processer, däribland gjuteri- och bearbetningsprocesser som också återfinns hos uppdragsgivaren. Det har också utförts en nulägesbeskrivning hos Järn AB för att se vilka möjligheter det finns med statistisk processtyrning och jämföra utgångsläget med studieobjekten. 

    Resultatet av studiebesöken gav att inget av de svenska företagen använde SPS i dagsläget även om vissa hade erfarenheter från ett tidigare användande och flera såg framtida möjligheter med SPS.

    Om personalen involveras i SPS-arbetet och får ansvaret för detta arbete så kommer det ge ökad motivation och större chans att skapa ett långsiktigt arbete. Det förutsätter att systemet är lättanvänt samt att användaren har fått rätt utbildning i området. Det är också viktigt att det går att justera en parameter i processen som är direkt kopplad till utfallet av SPS.

    De processer som visat sig lämpliga för SPS hos Järn AB är de bearbetningsprocesserna som inte är självjusterande. Gjuteri- och pulverpressning är relativt komplexa processer som gör det svårt att knyta specifika parametrar till utfallet och behöver mer utredning innan SPS kan införas.

    De styrdiagram som har visat sig lämpliga utifrån process- och hårdvarutekniska aspekter är R-diagram då dessa lämpar sig vid införandet av SPS på variabeldata och har stöd i föreslagen mjukvara. Vid ett senare skede är det också värt att titta på andra typer av styrdiagram som EWMA och CUSUM.

  • 45.
    Andersson, Dennis
    et al.
    Linköpings universitet, Institutionen för datavetenskap, Interaktiva och kognitiva system. Linköpings universitet, Tekniska högskolan. Swedish Def Research Agency, Linkoping, Sweden.
    Rankin, Amy
    Linköpings universitet, Institutionen för datavetenskap, Interaktiva och kognitiva system. Linköpings universitet, Filosofiska fakulteten.
    Diptee, Darryl
    Naval Postgrad Sch, USA.
    Approaches to team performance assessment: a comparison of self-assessment reports and behavioral observer scales2017Ingår i: Cognition, Technology & Work, ISSN 1435-5558, E-ISSN 1435-5566, Vol. 19, nr 2-3, s. 517-528Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Human factors research popularly employs perception-based techniques to investigate team performance and its dependency to cognitive processes. Such studies frequently rely upon either observer-based or self-assessment techniques to collect data. In this study, we examined behavioral observer ratings and self-assessment ratings for measuring team performance in virtual teams, with team performance regarded as a combination of task outcome and team cognition. Juxtaposing self-assessments and observer ratings from a quasi-experiment comparing team performance rating techniques reveals that they indeed produce overall similar results, with both singling out teamwork effectiveness ratings as the strongest contributor to overall team performance. However, the comparisons show remarkably low correlation on individual questionnaire items. The most striking difference is that the team members self-assessments of workload are lower than the corresponding observer ratings. In particular, the self-assessments do not correlate at all with overall team performance, whereas the observers workload ratings are more consistent with contemporary research that suggests a strong correlation between workload and team performance, suggesting that observer-based techniques are more reliable than self-assessments for assessing workload. For other ratings, the results show that the two techniques are fairly equal, suggesting that the choice between methods to employ can be deferred to other considerations such as obtrusiveness, accessibility, and resource availability.

  • 46.
    Andersson, Filip
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion.
    Martinsson, Niklas
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion.
    Filter cleaning device: for truck cab climate systems2018Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Scania has identified a problem among certain costumers in very dusty environments. The air filters for their truck’s climate system need extensive maintenance, replacement or manual cleaning, because of dust frequently loading up the filters. In this thesis the problem has been analyzed in order to find a solution. The process was initiated by the usage of the black box method, where needed transformations were found, resulting in three needed technical systems. Thereafter, brainstorming was used to find concepts for each technical system. Concepts were compared and ranked against each other. For the most critical of the three systems, the cleaning action, prototypes were built of the four highest ranked concepts. These prototypes were then used to compare the performance between the concepts.

    The selected filter cleaning device consists of a method to analyze filter blockage, alert the driver when cleaning is needed and a system to clean the filter for the Scania climate system. The system consists of a pressure sensor used to measuring filter blockage, an air pulse system which cleans the filter and a controller unit to control the cleaning cycle and to inform the driver. The air pulse system has two main parts, a pulse valve and an air tank. The pulse valve is used for releasing the air accumulated in the air tank. The complete system is supplied with 8.5 bar from the internal air pressure system in the truck and a 24 V power supply, also located in the truck.

    A suggestion on how a final implementation can be done has been developed, with a minimized number of variants and modifications of parts already in production. A proof of concept was built and mounted in a truck to validate the complete system. Numbers on cleaning performance and sound levels have been produced. The proof of concept manages to remove the restriction created from dust by approximately 50 %.

    Aside from developing a suitable filter cleaning device, figures on when the filter needs to be cleaned have been identified. To keep a good working environment within the cab a pressure drop over the filter of 936 Pa is recommended as a point of cleaning. This is to maintain the needed airflow of at least 123 m3/h with two persons seated in the cab to not exceed regulated levels of CO2 within the truck cab.

  • 47.
    Andersson, Frida
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell Produktion. Linköpings universitet, Tekniska högskolan.
    Hagqvist, Astrid
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell Produktion. Linköpings universitet, Tekniska högskolan.
    Sundin, Erik
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell Produktion. Linköpings universitet, Tekniska högskolan.
    Björkman, Mats
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell Produktion. Linköpings universitet, Tekniska högskolan.
    Design for Manufacturing of Composite Structures for Commercial Aircraft: The Development of a DFM strategy at SAAB Aerostructures2014Ingår i: Procedia CIRP, ISSN 2212-8271, Vol. 17, s. 362-367Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Within the aircraft industry, the use of composite materials such as carbon fiber reinforced plastics (CFRPs) is steadily increasing, especially in structural parts. Manufacturability needs to be considered in aircraft design to ensure a cost-effective manufacturing process. The aim of this paper is to describe the development of a new strategy for how SAAB Aerostructures addressing manufacturability issues during the development of airframe composite structures. Through literature review, benchmarking and company interviews, a design for manufacturing (DFM) strategy was developed. The strategy ensures that the important factors for successful DEM management are implemented on strategic, tactical and operational levels that contribute to a more cost-efficient product development process and aircraft design.

  • 48.
    Andersson Granberg, Tobias
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska högskolan.
    Norin, Anna
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska högskolan.
    Värbrand, Peter
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska högskolan.
    Yuan, Di
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska högskolan.
    Integrating optimization and simulation to gain more efficient airport logistics2009Ingår i: Eighth USA/Europe Air Traffic Management Research and Development Seminar (ATM2009), 2009, s. 1-10Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper we present airport logistics, which is a framework of resource management in the air transportation system. Focus is on the processes supporting turn-around. A detailed simulation model of various processes involved in turn-around is developed, by which the interaction between these processes are analyzed. We show that integrating optimization and simulation is a powerful tool to demonstrate efficiency improvements in airport logistics, using scheduling de-icing trucks as an example. An optimization algorithm for scheduling de-icing trucks is developed and simulations are performed comparing different schedules. The schedule obtained when considering total airport performance in the optimization algorithm gives minimum flight delay and waiting times in the simulations.

  • 49.
    Andersson Granberg, Tobias
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska fakulteten.
    Polishchuk, Tatiana
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska fakulteten.
    Polishchuk, Tatiana
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska fakulteten.
    Schmidt, Christiane
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska fakulteten.
    A framework for integrated terminal airspace design2019Ingår i: Aeronautical Journal, ISSN 0001-9240, Vol. 123, nr 1263, s. 567-585Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Route planning and airspace sectorisation are two central tasks in air traffic management. Traditionally, the routing and sectorisation problems were considered separately, with aircraft trajectories serving as input to the sectorisation problem and, reciprocally, sectors being part of the input to the path finding algorithms. In this paper we propose a simultaneous design of routes and sectors for a transition airspace. We compare two approaches for this integrated design: one based on mixed integer programming, and one Voronoi-based model that separates potential "hotspots" of controller activity resulting from the terminal routes. We apply our two approaches to the design of Stockholm Terminal Maneuvering Area.

  • 50.
    Andersson, Hans
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Företagsekonomi. Linköpings universitet, Filosofiska fakulteten.
    Berggren, ChristianLinköpings universitet, Institutionen för ekonomisk och industriell utveckling, Projekt, innovationer och entreprenörskap. Linköpings universitet, Tekniska fakulteten. University of Sussex.
    Kunskapsintegration och innovation i en internationaliserande ekonomi: Slutrapport från ett forskningsprogram2015Samlingsverk (redaktörskap) (Övrigt vetenskapligt)
    Abstract [sv]

    Den här skriften presenterar ett urval resultat och texter från forskningsprogrammet ”Kunskapsintegration och innovation i en internationaliserande ekonomi” (Knowledge Integration and Innovation in Transnational Enterprise, KITE) som finansierats av Riksbankens Jubileumsfond i två faser under åren 2007–2015. I programmet har vi analyserat hur företag, speciellt i tekniktunga industrier, påverkas av den allt mer globala konkurrensen om nya produkter och tjänster, hur nya specialiserade kunskaper växer fram och tas tillvara, och hur de kan förenas med existerande kunskapsbas. I denna skrift finns studier på tre olika nivåer: branschnivån, med analyser av innovationsprocesser och kunskapsutmaningar i industriella sektorer; företagsnivån, med skildringar av förändringar i företagens interna organisering av kunskapsbildande processer och undersökningar av nya former för utbyte och samspel mellan företag; samt mikronivån, med undersökningar av samspelet mellan individuella specialister inom företag. Skriften vänder sig både till den intresserade allmänheten och till forskare med annan vetenskaplig bakgrund. Fokus är på internationellt konkurrerande branscher och företag, men analyserna av kunskapens delning och sammanflätning, separation och integration, har bäring också på andra kunskapsintensiva sektorer och verksamheter, från statliga verk till sjukvård.

    En vetenskaplig presentation av programmets forskning under de första fyra åren finns i boken Knowledge Integration and Innovation: Critical Challenges Facing International Technology-Based Firms (redigerad av Berggren, Bergek, Bengtsson, Hobday & Söderlund och utgiven av Oxford University Press 2011). En uppföljande volym, Managing Knowledge Integration Across Boundaries, planeras av samma förlag 2016 (redigerad av Tell, Berggren, Brusoni & Van de Ven). I den medverkar ett antal internationella författare vilket visar kunskapsområdets globala tyngd och intresse. Under programmets drygt åtta år har deltagarna publicerat ett mycket stort antal artiklar, konferensbidrag, bokkapitel och liknande. För dessa hänvisar vi till programmets hemsida www.liu.se/kite.

    Vi har under hela programperioden arbetat intensivt med att diskuteraoch konstruktivt kritisera och utveckla varandras bidrag. Därför har det varit naturligt att denna skrift inbegriper många programdeltagares medverkan. En presentation av samtliga medverkande finns i slutet av denna skrift. Följande KITE-forskare har medverkat i nedan angivna kapitel:

    Hans Andersson (kapitel 4)

    Lars Bengtsson (kapitel 7)

    Marie Bengtsson (kapitel 3)

    Anna Bergek (kapitel 2)

    Christian Berggren (kapitel 1)

    Karin Bredin (kapitel 6)

    Cecilia Enberg (kapitel 5, 7)

    Mattias Johansson (kapitel 4)

    Nicolette Lakemond (kapitel 7)

    Lars Lindkvist (kapitel 3)

    Thomas Magnusson (kapitel 1)

    Camilla Niss (kapitel 6)

    Jonas Söderlund (kapitel 6)

    Fredrik Tell (kapitel 5)

    Vi vill också tacka Jenny Björkman på Riksbankens Jubileumsfond och Makadam förlag för deras engagerade arbete med redigering och produktion av slutresultatet.

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