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  • 251.
    Hedberg, Patrik
    et al.
    University of Skövde, School of Engineering Science.
    Shibli, Haidar
    University of Skövde, School of Engineering Science.
    Jämförelse av två konstruktionslösningar för en hjulaxel till en åkattraktion2018Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis is performed on behalf of the amusement park Skara Sommarland. The work is based on a comparative study of two different shafts for a rollercoaster. An already existing shaft in three parts, two shafts and one hub, while the new shaft design consists of one homogenous part machined from a solid bloc of material. The ends of the shafts for the current shaft design that are mounted in the hub are exposed to unnecessary wear. The thesis partly focuses on the causes of the fretting wear and possible actions to prevent or minimalize the damaged caused by fretting. The new shaft design leads to increased costs, which leads to monetary losses for the client compared to before.Haigh-diagrams are used to evaluate if the critical point of the design is in the safe area of the diagram, theoretical leading to an infinite lifespan of the shaft. Finite element analyses were performed in 3D CAD to simulate the shaft design and calculate the stresses in the design when under the maximum operational load.The result of the analyses shows that the current shaft suffers from plastic deformation while the new shaft design does not reach the yield strength of the material. Neither the current nor the new shaft design reach the ultimate tensile strength. Because the ultimate tensile strength is not reached there is no risk of crack initiation through finite fracture mechanics. For the current shaft design the results show that there occur movement between shaft and hub with high enough magnitude to be classified as one of the causes of the fretting.To avoid or minimize fretting several actions can be performed. Examples of pre-emptive actions are cleaning of surfaces before surface treatment for corrosion resistance.

  • 252.
    Hedenberg, Klas
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Åstrand, Bjorn
    School of Information Technology, Halmstad University, Halmstad, Sweden.
    3D Sensors on Driverless Trucks for Detection of Overhanging Objects in the Pathway2016In: Autonomous Industrial Vehicles: From the Laboratory to the Factory Floor / [ed] Roger Bostelman, Elena Messina, West Conshohocken, PA: ASTM International, 2016, p. 41-56Chapter in book (Refereed)
    Abstract [en]

    Human-operated and driverless trucks often collaborate in a mixed work space in industries and warehouses. This is more efficient and flexible than using only one kind of truck. However, because driverless trucks need to give way to driven trucks, a reliable detection system is required. Several challenges exist in the development of such a system. The first is to select interesting situations and objects. Overhanging objects are often found in industrial environments (e.g., tines on a forklift). Second is choosing a system that has the ability to detect those situations. (The traditional laser scanner situated two decimetres above the floor does not detect overhanging objects.) Third is to ensure that the perception system is reliable. A solution used on trucks today is to mount a two-dimensional laser scanner on top and tilt the scanner toward the floor. However, objects at the top of the truck will be detected too late, and a collision cannot always be avoided. Our aim is to replace the upper two-dimensional laser scanner with a three-dimensional camera, structural light, or time-of-flight (TOF) camera. It is important to maximize the field of view in the desired detection volume. Hence, the sensor placement is important. We conducted laboratory experiments to check and compare the various sensors' capabilities for different colors, using tines and a model of a tine in a controlled industrial environment. We also conducted field experiments in a warehouse. Our conclusion is that both the tested structural light and TOF sensors have problems detecting black items that are non-perpendicular to the sensor. It is important to optimize the light economy—meaning the illumination power, field of view, and exposure time—in order to detect as many different objects as possible.

  • 253.
    Hellberg, Patrik
    et al.
    University of Skövde, School of Engineering Science.
    Lindberg, Henrik
    University of Skövde, School of Engineering Science.
    Ställtidsförbättring på Cejn AB: SMED arbete i maskiner som bearbetar rostfritt material2015Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    Företaget Cejn AB har idag svårt att konkurrera prismässigt på marknaden när det gäller vissa rostfria detaljer. Ett led i att minska kostnaderna för att producera artiklarna är önskemålet från företagets sida att se efter om det går att genomföra en ställtidsreducering på maskincellen, se bilaga 5, som tillverkar rostfritt. Företaget har även önskemål om att en checklista ska tas fram för hur ställarbetet ska gå till i cellen, för om möjligt standardisera arbetet. Skiftgången i cellen är idag tvåskift och maskinerna är bemannade med en operatör per maskin och skift. Nulägesanalysen, som gjordes i början av projektet, visar att den genomsnittliga ställtiden idag är på ca 18 % av planerad produktionstid.

    Önskad arbetsmetod från företagets sida var SMED (Singel Minute Exchange of Die), metoden myntades av Shiego Shingo som kom fram till att ett ställ, tiden det tar att byta produktion i en maskin av en produkt till en annan, bör kunna ske på under tio minuter. Metoden bygger på att förvandla inre ställ, arbete som pågår när maskinen står still, till yttre ställ, arbete som pågår när maskinen går. Endast de moment som måste göras när maskinen står still ska vara med i det inre stället. För att mäta den effekt SMED-arbetet medför och för att se hur lång tid som varje moment tar användes en tidsstudie. Valet föll på att använda en kontinuerlig klocka under tidtagningen. Tidsstudiedokumentet som användes för att notera tiderna i var framtaget med ursprung i de inledande observationerna. Då Cejn AB har Lean som produktionsfilosofi har ett antal verktyg inom området använts under arbetet. Övergripande arbetsmetod för arbetet har varit PDCA (Plan, Do, Check, Act), där varje mindre moment i arbetet har delats ned i mindre PDCA-cykler.

    Utifrån den inledande tidsstudien beräknades ett teoretiskt resultat fram, det visar på att bara genom att förändra den ordning som operatören utför arbetsmomenten i går det att minska ställtiden med ca 20 %. För att verifiera det resultatet och för att testa den checklista som var framtagen gjordes en pilotstudie. Den visar på att förändringen är ca 11 %, vilket beror på att de ställ som observerades var krångligare och svårare än de som den inledande studien mätte. Ovanan med att arbeta utefter det nya arbetssättet för operatörerna är även det en bidragande orsak till att det är en diskrepans mellan teoretiskt och verkligt utfall. Under pilotstudien testades även den ställåda som var framtagen i projektet, vilket mottogs bra av operatörerna. Resultatet från pilotstudien visar att ställådan har effekt på momentet med att montera verktyg. Effekten är att tiden minskar med ca 8 % av att den inre ställtiden på det momentet.

    De av Cejn AB satta målen har uppnåtts då ställtidsreducering kan påvisas och checklistor har tagits fram. Det nya arbetssättet kan standardiseras av företaget.

  • 254.
    Helsing, Niklas
    et al.
    University of Skövde, School of Engineering Science.
    Nilsson, Simon
    University of Skövde, School of Engineering Science.
    3D-skrivare ur ett tillverkningsperspektiv2015Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    I detta examensarbete har en studie genomförts av hur väl 3D-skrivning kan tillämpas i Volvo Cars i Skövdes produktion. En litteraturstudie har genomförts för att åskådliggöra de olika 3D-skrivningsteknikerna och deras användningsområde. För att på ett överskådligt sätt jämföra de olika teknikernas duglighet har en bedömningsskala utvecklad av Nasa använts. Denna skala benämns som Technology Readiness Level (TRL). Den teknik som bedöms som mest lämplig med avseende på fullskalig produktion samt prototyptillverkning är Selective laser melting (SLM).

    För att åskådliggöra fördelar med 3D-skrivare har en förenklad 3D-modell av Volvos cylinderblock I5D modellerats. Denna förenklade modell har sedan modifierats för att åstadkomma en temperatursänkning som kan möjliggöra ett högre effektuttag. Två varianter av topologiska modifieringar presenteras. För dessa modifieringar har sedan värmelaster och kylning applicerats för att analysera värmespridningen i cylinderblocket. Jämförande mellan originaldesignen och de topologiska modifieringarna har sedan utförts. Målet med detta var att sänka den kritiska temperaturen i cylinderväggarna med åtminstone . Beräkningar har utförts med PTC/Creo.

    Med hjälp av TRL-skalan bedöms Selective laser melting vara den teknik som är mest lämplig för Volvo Cars i Skövde att tillämpa med avseende på prototyptillverkning. Med avseende på fullskalig produktion anses ingen av de teknikern som benämns i arbetet vara lämpliga.

    Resultatet visar att genom topologiska modifieringar kan temperaturen i det kritiska området sänkas med upp till 51 . En enkel kostnadsberäkning har utförts för att uppskatta hur mycket ett cylinderblock skulle kosta om den traditionella tillverkningen ersattes med 3D-skrivare. Detta visar att ett cylinderblock av typen I5D skulle kosta cirka 10 853 kr att tillverka med 3D-skrivaren X line 1000 R. I det priset är inte inköp av 3D-skrivaren inräknat. Rapporten diskuteras också följderna av resultatet. Vilka de potentiella felkällorna kan vara och vad som kan ha gjorts annorlunda. Det diskuteras också hur framtiden ser ut för 3D-skrivning och vad som skulle kunna göras som en naturlig fortsättning på detta examensarbete.

  • 255.
    Henriksson, Eva
    et al.
    University of Skövde, School of Engineering Science.
    Johansson, Sofie
    University of Skövde, School of Engineering Science.
    Utveckling av ett höj- och sänkbart elevbord2017Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    During the spring semester of 2017 a product development project has been carried out by two Design Engineering Students, Eva Henriksson and Sofie Johansson, in cooperation with Kinnarps. Kinnarps is a company who develops and sells furniture for public environments and as they are now focusing on the development of how educational spaces are formed and furnished they wanted to develop a height adjustable student desk for pupils between the ages of 10 to 16.

    To be able to reassure whether the correct customer requirements were identified and fulfilled in the right way QFD – Quality Function Deployment was used and analyzed as a part of the project. The use of QFD during the pre-study included, amongst other things, the execution of interviews and observations of users and the target group, performing competitive analyses, looking into trends , evaluate and weighing the importance of different needs and translating those into measureable specifications.The pre-study showed that needs like mobility, flexibility, simple adjustment and that the table should be as quiet as possible were the most important ones.The concept generation phase started by identifying and evaluating different options of height adjustment mechanisms. Creativity methods were used to generate ideas on how different parts of the table could be constructed. The generated concepts were then evaluated and screened continuously by looking on how well they fulfilled the customer requirements and through user tests and feedback from the target group.

    Two concepts remained before the final selection. The choice between these two concepts were based on to which extend each of them fulfilled the customer requirements. The final design of the table fulfills the requirements that were set and fits well into the educational spaces as they are formed today and how they probably will be designed in the future. The functionality that were requested by the users have been fulfilled while the table still has a unique and appealing look.

  • 256.
    Hermansson, Jakob
    et al.
    University of Skövde, School of Engineering Science.
    Wahlström, Emma
    University of Skövde, School of Engineering Science.
    Materialval för minskat slitage av sandformningsverktyg2017Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    At Volvo Group Trucks Operations (GTO) in Skövde, cylinder blocks, cylinder heads and flywheels are manufactured through sandcasting. As the forming tools that forms the sand forms are filled with sand, wear occurs where the sand particles hit the tool surface. The forming tool thus needs to be regularly maintained. The aim of this study is to evaluate alternative materials that the forming tools can be manufactured in to reduce wear, and thereby reducing costs by extending maintenance intervals. The problem is analyzed and a literature study on erosive and abrasive wear is carried out. A number of materials are presented as suitable candidates based on the literature study, material charts and discussion. Material samples are tested using a standard method for solid particle erosion using gas jets. Results from previous empirical studies indicate that erosion is strongly influenced by material properties such as hardness and toughness but also the angle of impingement and velocity of the erosive particles.The erosion test is performed at 30 and 90 degree angle of impingement. The test shows that the softer steel, Holdax and Sverker 21 have higher resistance to erosion at low angles of impingement and the harder steel Nimax has higher resistance at high angles of impingement. Nimax is considered a suitable material for the forming tool, as Nimax has the overall lowest erosion rate when adding the total erosion over both angles of impingement. Nimax has the lowest erosion rate at 30 degrees angle and is also considered to have good resistance to erosion at 90 degrees angle. Recommendation is given on repeated erosion tests to validate the results. There are also recommendations regarding material testing in the forming tool to see if a material change would lead to savings. Examination of possibilities to make changes in the sand filling process, altering angle of impingement between the sand blown and the forming tool as well as air pressure is recommended.

  • 257.
    Hjelm, Susanna
    University of Skövde, School of Engineering Science.
    Utveckling av en användarcentrerad designprocess för utformning av ergonomiska arbetsplatser enligt Lean2014Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [en]

    The mission of this thesis is to develop a user-centered design process for the design of ergonomic workstations that follows the guidelines and philosophy for Lean. The aim is to study the philosophies and management tools for Lean, Regulation of the Working Environment Act and other regulations and ergonomic guidelines that can be successfully integrated into product development processes. The starting point is to conduct a qualitative analysis of a prototype of an evaluation model for the Volvo Production System (VPS) developed by ergonomic experts at AB Volvo. The aim is to support the design process so that guidelines for Lean, legal requirements in the Work Environment Act and ergonomic requirements are naturally included in the typical phases of a design process; pre-study, definition of requirements specification, concept development, evaluation and detailed design. The qualitative analysis that was performed resulted in an integration of a number of aspects of Volvo's evaluation model VPS assessment of an overall design process. The results of the analysis was used as the foundation for the development of a user-centered design process. The conclusions drawn from the work is that aspects of VPS assessment can naturally be integrated into a generic design process in the concept development phases for designing ergonomic workplaces that meet guidelines for Lean as well as legal requirements of the Work Environment Act. 

  • 258.
    Hoang, Hue
    et al.
    University of Skövde, School of Engineering Science.
    Widerström, Matilda
    University of Skövde, School of Engineering Science.
    Simulation of distributed windings using the insert technique2019Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    During the insert process when the windings of an electric motor are pushed into the stator slots, some detrimental phenomena can occur that affect the efficiency and life of the motor. To detect these phenomena and optimize the process, a simulation would be useful. An investigation of the possibility to perform a simulation, using an appropriate numerical method for the insert process of distributed windings in a permanent magnet synchronous motor, was performed. During the project, a literature study was carried out to investigate existing methods and key-parameters for the simulation of the process. Explicit finite element method has been shown to be a suitable numerical method for simulating another winding process. An explicit finite element analysis was performed with a simplified model of the stator, the wires, the transmission tool and the needles by using the software Abaqus/CAE. In order to reduce the computational time, beam elements were used to model the wires and the other parts as rigid bodies. The model accounted for example contact and provided numerical results. The result was a suitable model. However, it needs to be developed further.

  • 259.
    Holm, Magnus
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Adaptive Decision Support for Shop-floor Operators using Function Blocks2017Doctoral thesis, monograph (Other academic)
    Abstract [en]

    In manual and semi-automation production systems, flexibility and adaptability are affected by the shop-floor operators’ skills, abilities and knowledge. Such dependencies highlight the vital importance of developing and utilising the knowledge, achievements and abilities of the operators working with production on the shop-floor. Teamwork, including both novice and highly experienced shop-floor operators, in a production environment with a high level of automation, is essential already today and is predicted to increase, when the complexity and demands of future production systems intensify. This trend is confirmed in both the research literature and by specialists within industry.

    The key to future competitiveness and effectiveness of the manufacturing industry is the shop-floor operators who handle the production systems. In addition, the future information intensive working environment, with its increasing complexity and less time available for decision-making, demands adaptive decision support and adaptive control systems that facilitate collaborative work on the shop-floor. It is therefore important to emphasise how decisions are supported in the time-limited working environment of the shop-floor, because this has a large impact on production output and quality and is vital to the success of the company. Consequently, this dissertation presents a framework for an adaptive decision support system that concentrates on shop-floor operators, in order to enhance their development and future contribution to leading edge production systems.

    The overall aim of the research presented is to define a framework for an Adaptive Decision Support System, to address the scope and demands of the future shop-floor, as indicated in the research literature, and confirm its relevance, as well as further elaborate it on the basis of interviews with production managers and HR specialists

    The research presented uses the design science research process. In parallel, decision support systems and the industrial shop-floor have been studied in the research literature and the current state of industrial practice has been assessed. These areas together form the basis for the research on adaptive decision support for shop-floor operators. A framework enabling adaptive decision support and adaptive system control, based on event-driven function block technology and Augmented Reality technology, is formulated.

    The gap of research on decision support for shop-floor operators, indicated in the research literature is addressed by the research preformed.  Adaptive and dynamic decision support and system control able to process vast amounts of information in real time demonstrates utility for shop-floor operators. The research presenting the Adaptive Decision Support System has demonstrated its utility for shop-floor systems and production operatives in two extensive studies using demonstrators based on real-life production environments.

    A methodology, the ‘User group’, has been formulated for research collaboration and bi-directional knowledge transfer between academia and the industrial partners. It provides tools that enable cooperation between the experienced research partner and the novices, despite their different levels of engagement in the same project, without dividing them into separate groups. The ‘user group’ case study presented describes how both the inexperienced and the research mature companies gain new knowledge and engage in ongoing research. By doing so, the industrial project partners have extensively supported the research presented and will subsequently be the expected beneficiaries.

  • 260.
    Holm, Magnus
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    The future shop-floor operators, demands, requirements and interpretations2018In: Journal of manufacturing systems, ISSN 0278-6125, E-ISSN 1878-6642, Vol. 47, p. 35-42Article in journal (Refereed)
    Abstract [en]

    The evolution of the manufacturing industry reveals continuous progress and development throughout the years. This evolution not only includes production methodologies and the production equipment, it also includes the working environment of the shop-floor operators. The demands faced by the shop-floor operators have developed from strictly controlled, simple and monotonic tasks to self-controlled team work requiring a holistic approach that aims at continuous improvements and achieving a high degree of flexibility, adaptability and initiative.

    This paper describes the evolution of the shop-floor operator, according to the research literature and interviews with manufacturing managers and human resources specialists. In addition, the paper presents the response of future Swedish shop-floor operators, today’s high-school students, to a description of their possible future work as shop-floor operators. The Swedish manufacturing industry competes, to a large extent, on and responds to the international market. The findings made in this paper are thus also interesting for other industries and countries acting on the international market.

  • 261.
    Holm, Magnus
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Adamson, Göran
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Moore, Philip
    Academy of Innovation & Research, Falmouth University, Cornwall, United kingdom.
    Wang, Lihui
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. KTH Royal Institute of Technology, Stockholm, Sweden.
    Why I want to be a future Swedish shop-floor operator2016In: Research and Innovation in Manufacturing: Key Enabling Technologies for the Factories of the Future - Proceedings of the 48th CIRP Conference on Manufacturing Systems / [ed] Roberto Teti, Elsevier, 2016, Vol. 41, p. 1101-1106Conference paper (Refereed)
    Abstract [en]

    When looking in rear view mirrors the Swedish as well as the international production industries can overview several years of progress covering all aspects of production. Production methodologies and machines etc. have changed and evolved, and so has the environment of the shop-floor operator. The demands on the shop-floor operators have grown from simple monotonic tasks with low complexity to pro-active team work requiring flexibility, continuous improvements and a holistic approach. With a base in a study where production and HR-managers at six Swedish manufacturing industries have been interviewed this paper identifies the role of today’s and the future Swedish shop-floor operator. The response to the described role of the future operator is compiled from the ones who will become the future Swedish shop-floor operators – today’s teenagers attending technical high-school. Their views of the environment of the future shop-floor operator are described by accuracy, development, a good working environment and team work. The paper also reveals what the offer should include to make these teenagers say: I want to be a future Swedish shop-floor operator.

  • 262.
    Holm, Magnus
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Adamson, Göran
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Wang, Lihui
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Moore, Philip
    Academy of Innovation & Research, Falmouth University, United Kingdom.
    Framework for an adaptive decision support system for industrial shop-floor operators2014Conference paper (Refereed)
    Abstract [en]

    Today’s shop-floor operators’ working tasks often stretches over a broad spectra of jobs; from ordinary production assignments to handling errors and performing maintenance. Demands for enhanced skills and knowledge are constantly raised to limit the consequences of tool breakage, machine down time and other stochastic events negatively affecting the production.

    To be able to meet these increasing demands a framework for a distributed and adaptive decision support system is proposed. It will help the shop-floor operator to distinguish between decision options and minimize time to consider appropriate actions to maximize productivity both during normal production and when facing unexpected or unscheduled events.

    In what ways is it possible to support operators in making decisions for optimal productivity?” was the opening question from the industry partner when beginning this research. Targeting this question a novel framework for an adaptive decision support system (DSS) enabled by event-driven function blocks, based on decision logics is proposed. Its ability to adapt to the actual conditions on the shop-floor is compared to a currently used voice message system in a test case.

  • 263.
    Holm, Magnus
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Adamson, Göran
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Wang, Lihui
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Moore, Philip
    Academy of Innovation & Research, Falmouth University, United Kingdom.
    The Future Swedish Shop-Floor Operator – Interviews with Production Managers2014In: Proceedings of the sixth Swedish Production Symposium, 2014, 2014Conference paper (Refereed)
    Abstract [en]

    This paper is based on a study in which production and HR managers at six Swedish manufacturing industries have been interviewed about the role of the shop-floor operator, taking off in today’s situation in trying to identify the future one. As well as the production methods and the machines etc. in the production system continuously evolve, so does the environment of the shop-floor operator. Increasing complexity in the production systems raises demands on the operators’ ability to handle ICT-tools to gain decision support and knowledge needed in the future shop-floor environment. 

  • 264.
    Holm, Magnus
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Cordero Garcia, Aimar
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Adamson, Göran
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Wang, Lihui
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Adaptive decision support for shop-floor operators in automotive industry2014In: Procedia CIRP, ISSN 2212-8271, E-ISSN 2212-8271, Vol. 17, p. 440-445Article in journal (Refereed)
    Abstract [en]

    Today's operators on factory shop-floors are often not stationed, dealing with a single or few tasks but have increasing responsibilities demanding enhanced skills and knowledge in a production environment where any disturbance must be settled with adequate actions without delay to keep optimum output. To be able to respond to these demands, the operators need dynamic, distributed and adaptive decision support in real-Time, helping them to distinguish decision options and maximizing productivity despite incoming stochastic events. The minimum of time and option for operators to consider appropriate action both during normal production and when facing unexpected or unscheduled events point out the need of adaptive decision support for operators. When initiating this research project the question from the industry partner was the following: In what ways is it possible to support operators in making decisions for optimal productivity? By targeting this problem this paper introduces a novel framework for an adaptive decision-support system enabled by event-driven function blocks and based on decision logics. The proposed decision support systems' ability to adapt to the actual conditions on the shop-floor is validated through a case study, and its capability is compared to the voice message system installed on-site.

  • 265.
    Holm, Magnus
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Danielsson, Oscar
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Syberfeldt, Anna
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Moore, Philip
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Wang, Lihui
    Sustainable Manufacturing, KTH Royal Institute of Technology, Kungliga Tekniska Högskolan, Stockholm.
    Adaptive instructions to novice shop-floor operators using Augmented Reality2017In: Journal of Industrial and Production Engineering, ISSN 2168-1015, Vol. 34, no 5, p. 362-374Article in journal (Refereed)
    Abstract [en]

    This paper presents a novel system using Augmented Reality and Expert Systems to enhance the quality and efficiency of shop-floor operators. The novel system proposed provides an adaptive tool that facilitates and enhances support on the shop-floor, due to its ability to dynamically customize the instructions displayed, dependent upon the competence of the user. A comparative study has been made between an existing method of quality control instructions at a machining line in an automotive engine plant and this novel system. It has been shown that the new approach outcompetes the existing system, not only in terms of perceived usability but also with respect to two other important shop-floor variables: quality and productivity. Along with previous research, the outcomes of these test cases indicate the value of using Augmented Reality technology to enhance shop-floor operators’ ability to learn and master new tasks.

  • 266.
    Holm, Magnus
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Frantzén, Marcus
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Aslam, Tehseen
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Moore, Philip
    Falmouth University, Penryn, Cornwall, United Kingdom.
    Wang, Lihui
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. KTH Royal Institute of Technology, Stockholm, Sweden.
    A methodology facilitating knowledge transfer to both research experienced companies and to novice SMEs2017In: International Journal of Enterprise Network Management, ISSN 1748-1252, Vol. 8, no 2, p. 123-140, article id IJENM0080202Article in journal (Refereed)
    Abstract [en]

    In this paper, knowledge transfer is defined as a process of disseminating both technological and theoretical understanding as well as enhancing both industrial and academic knowledge through conducted research to project partners collaborating within a research project. To achieve this, a new methodology called 'user groups' is introduced. It facilitates knowledge transfer between project participants in collaborative research programs engaging both experienced and unexperienced partners regardless of level of input. The introduced methodology 'user groups' provides tools for collaborating with several research partners even though their levels of engagement in the project and prior research experience may vary without dividing them into separate groups. It enables all project partners to gain new knowledge and by so doing extending the knowledge society. The case study shows that the eight engaged companies are able to cooperate, achieve their own objectives and, both jointly and individually, contribute to the overall project goals.

  • 267.
    Holm, Magnus
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Givehchi, Mohammad
    University of Skövde.
    Mohammed, Abdullah
    University of Skövde.
    Wang, Lihui
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Web based monitoring and control of distant Robotic Operations2012In: Proceedings of the ASME 2012 International Manufacturing Science and Engineering Conference MSEC2012 June 4-8, 2012, Notre Dame, Indiana, USA, ASME Press, 2012, p. 605-612Conference paper (Refereed)
    Abstract [en]

    In order to improve the production efficiency while facing today’s manufacturing uncertainty, responsive and adaptive capabilities for rapid production changes are essential. This paper presents how dynamic control and real-time monitoring (embedded in a web-based Wise-ShopFloor framework) can integrate virtual models with real shop floors. Wise-ShopFloor (Web-based integrated sensor-driven e-ShopFloor)uses Java technologies (e.g., Java Servlet and Java3D) for implementing the system. It allows the operators, both remote and on-site, to monitor and control machines, devices and operations on a shop floor, based on run-time information from the connected machines, devices and their sensors. Two case studies are presented to demonstrate the approach towards web-based adaptive manufacturing. The first demonstrating how OPC-technology is used to improve the monitoring and control capabilities of the production and the second one focusing  on remote control of a robot eliminating the need of motion planning and tedious robot programming.

  • 268.
    Hoyos Rodriguez, David
    University of Skövde, School of Engineering Science.
    Realistic Computer aided design: model of an exoskeleton2019Independent thesis Advanced level (degree of Master (One Year)), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    The musculoskeletal disorders have significant health care, social and economic consequences in the factories nowadays. One of the most promising possible solutions is the use of exoskeletons in the workstations. Exoskeletons are assistive wearable robotics connected to the body of a person, which aims to give mechanical power or mobility to the user (Wang, Ikuma, Hondzinski, & de Queiroz, 2017).

    The objective of this project is to create a realistic CAD model of a passive exoskeleton which will be used in future research to analyse the behaviour of the workers in a virtual environment with and without the exoskeleton. This model will be a virtual representation of the exoskeleton EKSOVest which has been designed to support these workers who have to realize overhead tasks. This virtual representation will be carried out in PTC CREO and exported to IPS IMMA in order to check the viability of this model. To achieve a realistic model, the exoskeleton should have the same characteristics than the real exoskeleton. The objectives of this project will be defined for these characteristics, which are part creation, mechanisms, forces simulation, and parametrization. The parts and the mechanisms will be created and defined in PTC CREO with the same dimensions and behaviour as the real exoskeleton. Furthermore, this report will be focussed mainly in force simulation and the parametrization.

    The forces of the EKSOVest are generated by two different spring and by a high-pressure spring. To simulate these forces, the equation of these springs will be obtained and introduced in PTC CREO. These equations will be obtained through the regression of a set of points, which will be obtained from the real exoskeleton using a dynamometer. The parametrization will be carried out with the objective to make the virtual model adaptable for every type of mannequins. This parametrization will modify the length of the exoskeleton’s spine bar and the distance between the mechanical arms. These distances will be adapted according to the mannequin’s measures which will be introduced by the user. The measures that have to be introduced by the user are shoulder height, liac spine height, and chest width.

    In conclusion, it can be said that the regression of the springs obtained are an accurate result which can imitate quite well the forces of this exoskeleton. Furthermore, the results of the parametrization allow the exoskeleton adaptable to any type of dimensions that the mannequin could have. The final model obtained has been exported to IPS IMMA and implemented in a mannequin.

  • 269.
    Huang, Rui
    et al.
    School of Computer Science, Nanjing University of Posts and Telecommunications Nanjing City, China.
    Ericson, Stefan
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    An Efficient Way to Estimate the Focus of Expansion2018In: 2018 3rd IEEE International Conference on Image, Vision and Computing (ICIVC 2018), IEEE, 2018, p. 691-695Conference paper (Refereed)
    Abstract [en]

    Detecting independent motion from a single camera is a difficult task in computer vision. It is because the captured image sequences are the combinations of the objects' movements and the camera's ego-motion. One major branch is to find the focus of expansion (FOE) instead as the goal. This is ideal for the situation commonly seen in UAV's camera system. In this case, the translation is dominant in camera's motion while the rotation is relatively small. To separate the ego motion and scene structure, many researchers used the directional flow as the theoretic basis and extracted its properties related to FOE. In this paper, we formulate finding FOE as an optimizing problem. The position of FOE has the minimal standard deviation for the directional flow in all directions, which is also subjected to the introduced constraint. The experiments show the proposed methods out-perform the previous method.

  • 270.
    Huertas, Ana
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. Volvo Cars Corporation.
    Decision support system for feeding policy selection in production settings: Research proposal2016Report (Other academic)
    Abstract [en]

    Competitiveness is highly important in automotive industry. Customers’ satisfaction is decisive and that has turned out in high vehicle customization. Customization implies for example that a vehicle model can include several types of engines; inferring in high engine model variety on the assembly systems. Production lines balancing and ergonomic factors within assembly operations usually trigger unbalances on the logistics resources utilization. A proper feeding policy selection can palliate the impact of the unbalances generated by the assembly operations, improve the performance of the system and reduce cost. Selection among different policies is often done by following qualitative criteria which are influenced by product structure, operational constraints, company-specific practices and tradition. This project consists of the development of a decision support system for feeding policy selection in production settings. This system will automatically select the feeding policy at a single component level and evaluate the impact brought by this decision when interacting with the production setting. 

  • 271.
    Hultman, Madeleine
    University of Skövde, School of Engineering Science.
    Tillverkningsprocesser för fläktväggar: Förslag på nya processer2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project has investigate one manufacturing processes at a manufacturing company. The company has been Swegon Operations AB and is located in Kvänum, where they manufacture units for indoor climate.

    The current study investigation is on a fan wall, which is a sheet wall adjacent to the fan in the units. The purpose of the project is to identify the current manufacturing process with both customer and product requirements. Subsequently give two alternative manufacturing processes one internally and one external manufacturing process. Which can make the fan wall and meet the requirements for the costumer and product with the lowest manufacturing cost.

    In the current process, the fan wall is manufactured in a value flow consisting of three activities in the process. The problem with this process is that it has not been investigated and compared with other alternative manufacturing processes with a lower manufacturing cost. Today's manufacturing process has been in place since 2001 when a custom-made machine was installed in the factory.

    The study in the project has investigated a value stream analysis for the current process, the possibilities for developing the process and how a future version of the manufacturing processes could look. The two alternative manufacturing processes are internal and external processes. The internal process consists of existing machinery from the factory and the external process consists of existing machinery and a plastic item is purchased externally.

    The study has also focused on sustainable development and Plan Do Check Act (PDCA). Consider why sustainable development is something that has to take into account and how the company works with it, as well as draw conclusions about how the different processes affect. The process of the entire project has followed the PDCA by first planning the entire work up and a value stream analysis is made to find possibilities and know the starting point. Then implement the possibilities of the proposed processes of how they would result and then check through analyses to propose the best manufacturing process. In the end, follow up that all goals have been met.Investigate how todays and the two proposed processes can affect the environment and the study has been structured according to PDCA. Analysis of costs, lead time and pros and cons will be discussed and conclusions about the project will be presented.

  • 272.
    Hylander Ruiz, Gustavo
    University of Skövde, School of Engineering Science.
    Sustainable delivery vehicle for last mile delivery services2019Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Pollution levels in urban areas continue to rise, with transportation being the number one cause. As cities ban fossil fuel cars access to the city center, this project looks at the delivery of packgaes from internet purchases. A three-wheeled, human-powered and electrically assisted vehicle is designed. This vehicle is dsigned to work together with last-mile logistics. A scientific design process was carried out to define the stakeholders, competition and requirements of the project, among others.The results yielded a semi-finished vehicle, comprising of the frame, general design, FEA analysis, delivery system and an optimization process for the frame. Future work includes economical or social study, design of the brakes and gear system or a design of the frame-cabin connection.

  • 273.
    Häggblom, Hanna
    University of Skövde, School of Engineering Science.
    Tillståndsbaserat underhåll på verktygsmaskiner: Utvärdering av det tillståndsbaserade underhållet på verktygsmaskiner hos Volvo Cars i Skövde och hur det kan utvecklas2013Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A company can use different strategies when performing maintenance. One strategy is corrective maintenance where maintenance is carried out after a failure has occurred. Another strategy is preventive maintenance. A combination of the two is often used. The preventive maintenance can be predetermined or condition based. Advantages with the condition based maintenance are e.g. that the replacement of parts can be planned according to observations indicating there’s an increasing risk of failure. When choosing preventive maintenance, the RCM method can be used to determine risk of failure modes and the cause of function failures. Decisions regarding the preventive maintenance should be based on knowledge in new techniques, history of failures and the equipment and competence available.

    Volvo Cars in Skövde is doing more or less the same preventive maintenance on machine tools regardless of whether it’s a new or old machine. The company is using condition based maintenance on some of the components and units. Mostly it consists of human inspections, a subjective control of the machine’s condition, and spindle vibration analysis. Through interviews it has been determined that new techniques are rarely implemented and that the decided maintenance plan for a machine is rarely changed. The company is aware of the development of new techniques for condition based maintenance and wants to investigate whether it is appropriate to evolve their condition based maintenance on machine tools. The techniques further investigated are measurement with Ball bar, monitoring of process parameters and geometrical verification.

    To make accurate decisions regarding the implementation of new techniques, a data collection of the history of frequent failures was done. To limit the amount of data a five year old processing line was studied. Data from the maintenance system Maximo was sorted by long failures from the recent years and by prioritizing with the Pareto principle it showed the recurring failures of ball screws. The component do have a condition based maintenance activity today, there is an inspection once a year. However, the inspection is rarely able to predict or find a failure on the ball screw. Four out of twenty-seven ball screws with fault have been changed after inspection over the last five years. By mapping the components failures on fifteen machine tools and when preventive maintenance has been done, several options for improvements were found.

    The cost of the replacement of a ball screw when a failure has already occurred is as much as ten times the cost of replacement before failure. This is caused by cost of scrap and long down time. A new, improved preventive maintenance task is therefore highly justified. The motif is both reducing the scrap cost related to failure and with increased availability.

    The company is recommended an investment in Ball bar as a new method for condition based maintenance. It should be used to increase the objective control of the mechanical parts of a machine tool. The method is not totally new for the company and relatively easy to implement. The current subjective control on the machine tools should be revised to increase the probability of finding degradation of functions. Today the activity takes rather long time and has therefore not been done in time, it should be shorter. The company is also recommended to investigate new methods for preventive maintenance continually. Today there is no employee with that mission and to evolve maintenance, the company has to be updated on new techniques.

  • 274.
    Hägglund, Mathias
    et al.
    University of Skövde, School of Engineering Science.
    Berglund, Erik
    University of Skövde, School of Engineering Science.
    ROTORSAKSANALYS AV TIDIGARE 5S-ARBETE PÅ ETT TILLVERKANDE FÖRETAG I SKARABORG2017Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    Cementa AB är ett företag som idag ingår i Heidelberg koncernen som är en stor aktör inom tillverkning av cement. Företagets anläggning i Skövde har som uppgift att implementera 5S i sina lokaler främst inom underhållsavdelningen. På grund av tidigare misslyckat försök har företaget inte lyckats att implementera 5S fullt ut i företaget men kommer 2017 att göra ett nytt försök för att kunna lyckas implementera 5S i verksamheten. Denna gång tar företaget in två studenter från Högskolan i Skövde vars uppgift blir att ta reda på varför den tidigare implementeringen misslyckades och vad som kan göras bättre vid ny 5S-implementering.Examensarbetet går ut på att genomföra en rotorsaksanalys av de tidigare försök av varför 5S inte lyckades drivas igenom på Cementas underhållsavdelning och eventuellt hur företagets operatörer och ledning bör jobba vidare för att lyckas med 5S-implementering och inte riskera att hamna i samma situation.Teorin som examensarbetet använder sig av stöds från hållbar utveckling och Lean-filosofin, med metoden 5S och slöseri. Teori om att lyckas med förbättringsarbeten tas med, för att kunna förklara hur förbättringsarbeten bör utformas och vilka viktiga delar som behöver finnas med för att lyckas med en ny metod eller ett arbetssätt inom en verksamhet.Metoderna som tillämpades var observationer, intervjuer med ledning, enkät med operatörer och en workshop. Alla resultat som studenterna fick från ledningen och operatörer sammanställdes och jämfördes mot teori för att se vilka orsaker som påverkade den tidigare misslyckade 5S-implementationen och hur nuläget ser ut för att kunna implementera 5S i verksamhetens underhållsavdelning.Resultatet sammanställdes och presenteras varför förbättringsarbetet med 5S misslyckades och vilka bidragande orsaker som avgjorde resultatet. Även vilka slöseri som kunde identifieras och dess negativa orsaker och påverkande faktorer på underhållsavdelningen redovisades.Det som framkommer av resultatet är att ledningen och operatörer har skilda åsikter som påverkar en 5S-implementering i nuläget. Men det finns även gemensamma åsikter som kan stödja en framtida 5S-implementering. Att påbörja en implementering utan kunskap om metoden skulle riskera ännu en misslyckad 5S-implementering i lokalerna.Det som påverkar är att inga tydliga mål har satts med vad verksamheten vill få ut av 5S. Andra faktorer var kunskap och brister om förståelse vad 5S är för något och hur arbetet ska bedrivas för att lyckas.Bristerna identifierades och förklaras i rapportens diskussionsdel där resultatet av studien kommenteras hur det har varit och vilka påverkande händelser som har lett till resultatet av arbetet på Cementa. Åtgärdsförslaget till fortsatta arbete för 5S på Cementa förklaras stegvis i rapporten, hur de skall jobba vidare med 5S och möjligheten att kunna nå målet dit hela företaget strävar efter att få komma. Förslaget är inspirerat av ett liknande företag som tillämpade en lyckad metod för sin 5S-implementering.

  • 275.
    Häggström, Maja
    et al.
    University of Skövde, School of Engineering Science.
    Holstensson, John
    University of Skövde, School of Engineering Science.
    Utveckling av hyttmodul för fritidsbåt2016Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Since the end of the 1950s the boat manufacturer Ryds, situated in Småland, has been producing everything from canoes to cabin boats. Their latest successful cabin boat was last manufactured in 2012 and since then the company has modernized their production plant and new goals and methods have been introduced. This new way of manufacturing boats, including modular design, have not yet given the opportunities of introducing a new cabin boat, which is now one of the company’s strong visions for 2017. This thesis has been carried out at the University of Skövde in collaboration with Ryds, with the same goals and vision. The project goal was to develop a cabin boat through methods of module design and new assembly strategies in the boat manufacturing industry. The cabin module was to be assembled as an external part to an existing leisure boat with the main focus on areas such as safety, performance, design and cost efficiency.

    Requirements for the cabin boat were to withstand the marine environment in terms of weather and water conditions as well as mechanical stress. The design and manufacturing costs were to be adapted to the target group preferences and competing cabin boats of similar size. Target group of this project were archipelago habitants which use the boat as their main transport every day all year round more or less.

    The initial phase of the project was to collect necessary information of boat manufacturing, suitable material as well as performing interviews and analysing competitors’ design and manufacturing strategies. Information about competitors was mainly collected through the Boat Show 2016 in Gothenburg. Using this background information a set of requirements were established. This specification list was used as the basis platform for concept generation, concept evaluation and prototyping phases as well as the conducting of mechanical strength calculations, which resulted in a finished cabin boat concept.

    The developed cabin module is carefully balanced in manufacturing and assembly, costs suited for the target group’s wallets and a design adapted to the existing hull and Ryds’ profile. The cabin module fulfils the mechanical strength requirements and the strains from the marine environment. Ergonomic aspects have been adapted to existing and competing cabin boat dimensions. The assembly of the cabin boat is done by lowering a cockpit into the deck of the leisure boat, whereupon lists, windows, doors, hatches and roof are assembled followed by final sealing. Two suggestions of aesthetic character have been presented to demonstrate the possibilities of personal equipment and expressions. 

  • 276.
    Häkkinen, Markus
    University of Skövde, School of Engineering Science.
    Viktiga faktorer produktutveckling enligt set based concurrent engineering2016Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Product development usually has the same general approach: A specification for a new product is provided to the product development department from the marketing department. Product developers then generate concepts which are developed into prototypes before the products are manufactured and sold. The procedure usually differs by the use of different models such as Lean product development or integrated product development in the process.

    The part of Lean product development (LPD) that is used when developing concepts is called set based concurrent engineering (SBCE) and these are new concepts in Sweden. What is required to work with set based concurrent engineering in a successful manner? Is it possible to identify important factors when developing products using SBCE in companies?

    A literature study which resulted in a list with five potentially important factors when developing products using SBCE was created before a qualitative study was conducted at five companies. Semi structured interviews were conducted at Husqvarna, Saab, Furhoffs, Ericsson Radio and GKN Aerospace to gather data for an analysis. In the analysis, comparisons were made between the companies’ way of developing products with the list that was created in the end of the literature study.

    A conclusion of the study was a number of important factors when developing products using SBCE could be: Wide solution space, Knowledge based screening of concepts, Recycling of knowledge, Technically competent project management, Cross functional teams.

    The study also showed that an investment in the right type of leadership could potentially be an important factor when implementing SBCE since the company management need to understand the working model if SBCE is going to have a positive effect.

  • 277.
    Härström, Andreas
    et al.
    University of Skövde, School of Engineering Science.
    Gunnarson Ljungblom, Joel
    University of Skövde, School of Engineering Science.
    Optimering Scania DL: VICI Industri AB2015Independent thesis Basic level (professional degree), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    Vici Industri AB är ett företag som tillverkar vipparmar vilket är en ingående komponent i förbränningsmotorer. Segmentet som företaget verkar inom är den tunga fordonsindustrin och de är leverantör åt bland annat Scania och Volvo. Scanias vipparmar tillverkas i en produktionsprocess som kallas Scania DL. Uppgiften som tilldelades syftade till att undersöka nuvarande kapacitet, ta fram valid simulering för att därigenom påvisa kostnadseffektiva åtgärder.

    Data som krävdes för att validera simulering fanns inte i dåvarande dagsläge och därför krävdes ett grundligt undersökande av produktionsprocessens kapacitet. Det genomfördes även för att påvisa de brister som fanns i nuläget. Flertalet produktionstekniska verktyg användes till analysering för att nå korrekt rotorsak och utifrån det togs förslag, till åtgärder att tillämpa, fram. Dessutom togs valid simulering fram som användes för att experimentera och påvisa effekten av de framtagna åtgärderna.

    Genom initial stopptidsuppföljning gick det bland annat att belysa att reaktionstiden stod för cirka 35 % av stopptiden. Dessutom framkom de stopporsaker med högst frekvens som stod för största delen av stopptiden. Efter analysering av orsaker och framtagna åtgärder visades en möjlighet att i genomsnitt öka output med cirka 10 %. Arbetet i sig har gett en möjlighet att lyfta fram de slöserier som förekommer i produktionsprocessen och med hjälp av det framföra förbättringspotential.

  • 278.
    Högberg, Dan
    University of Skövde, School of Engineering Science.
    Use of finite element method in trailer deck design2001In: Journal of Materials Processing Technology, ISSN 0924-0136, E-ISSN 1873-4774, Vol. 117, no 1-2, p. 238-243Article in journal (Refereed)
    Abstract [en]

    The employment of the finite element (FE) method in conceptual and detail design of a secondary deck platform for trailer bodies is presented. The main objective of the project is to design a versatile, light and cheap secondary deck. To assist the designer with sufficient means for the concept generation and evaluation process, the FE method is used in order to gain fair structural analysis data. Assistance from the computer software stimulates creativity, reduces the time required in the design process, and eventually increases probability to gain customer satisfaction. This approach is precise enough for comparison purposes at this stage of the design process. The structural data gained is compared mainly with weight and access criteria.

  • 279.
    Högberg, Dan
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Brolin, Erik
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. Department of Product and Production Development, Chalmers University of Technology, Gothenburg, Sweden.
    Hanson, Lars
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. Department of Product and Production Development, Chalmers University of Technology, Gothenburg, Sweden / Industrial Development, Scania CV, Södertälje, Sweden.
    Accommodation levels for ellipsoid versus cuboid defined boundary cases2015In: Procedia Manufacturing, ISSN 2351-9789, Vol. 3, p. 3702-3708Article in journal (Refereed)
    Abstract [en]

    The boundary case method is established for the representation and consideration of anthropometric diversity in design tasks with certain characteristics. Sometime boundary cases are defined separately for two distributions, e.g. for females and males, which may lead to a situation where some boundary cases will be redundant in that they are located within the joint distribution rather than on the joint boundary. This paper describes and illustrates a method for automatic identification of redundant boundary cases that are located within two three-dimensional overlapping distributions.

    Practitioner Summary: The paper describes a pragmatic way to focus the design work on users with specific limiting body measurement combinations that can be used to obtain design data or be used to describe appropriate test persons or digital human models for design problems where the boundary case method is suitable.

  • 280.
    Högberg, Dan
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Brolin, Erik
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Hanson, Lars
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Accommodation levels for ellipsoid versus cuboid defined boundary cases2015In: Proceedings of the 6th International Conference on Applied Human Factors and Ergonomics (AHFE 2015), AHFE , 2015Conference paper (Refereed)
    Abstract [en]

    The definition and use of boundary cases is a common approach when aiming to anthropometrically accommodate a desired percentage of the targeted population by a design. The cases are defined based on anthropometric data that represents the targeted population. Approaches that define cases based on the variation within just one body measurement are poor for most design problems in representing anthropometric diversity. Hence, the consideration of variation within several body measurements is preferred. However, an approach that is based on performing several separate studies of the variation within a number of measurements leads to undesired reduction of accommodation due to the lack of consideration of the effects of correlations between measurements. This paper compares theoretical accommodation levels when using an ellipsoid versus a cuboid based approach for defining boundary cases to represent anthropometric variation within three body measurements. The ellipsoid approach considers correlations between body measurements whereas the cuboid approach does not consider correlations between body measurements. The paper suggests the application of the ellipsoid method for defining boundary cases for better reaching desired accommodation levels in boundary case based design problems. These cases can be used to define computer manikins when using digital human modelling tools. The method is also applicable when wishing to select extreme but representative real people to be involved in physical fitting trials.

  • 281.
    Högberg, Dan
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Brolin, Erik
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. Department of Product and Production Development, Chalmers University of Technology, Gothenburg, Sweden.
    Hanson, Lars
    Department of Product and Production Development, Chalmers University of Technology, Gothenburg, Sweden / Industrial Development, Scania CV, Södertälje, Sweden.
    Basic Method for Handling Trivariate Normal Distributions in Case Definition for Design and Human Simulation2014In: Advances in Applied Digital Human Modeling, AHFE Conference , 2014, p. 27-40Conference paper (Refereed)
  • 282.
    Högberg, Dan
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Brolin, Erik
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Hanson, Lars
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. Industrial Development, Scania CV.
    Concept of Formalized Test Procedure for Proactive Assessment of Ergonomic Value by Digital Human Modelling Tools in Lean Product Development2018In: Advances in Human Factors in Simulation and Modeling: Proceedings of the AHFE 2017 International Conference on Human Factors in Simulation and Modeling / [ed] Cassenti, Daniel N., Cham, Switzerland: Springer, 2018, Vol. 591, p. 425-436Conference paper (Refereed)
    Abstract [en]

    A concept of a formalized test procedure for proactive assessment of ergonomic value by digital human modelling (DHM) tools in lean product development (LPD) is proposed and described. The objective of the formalized procedure is to integrate the utilization of DHM tools in LPD and to support the delivery of ergonomic value and reduce waste in product and production development processes. A design process model is illustrated and described, and examples are given of how to specify and work with ergonomic value in the process.

  • 283.
    Högberg, Dan
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Brolin, Erik
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. Chalmers University of Technology.
    Hanson, Lars
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. Chalmers University of Technology / Scania CV.
    Identification of redundant boundary cases2015In: Proceedings of the 19th Triennial Congress of the International Ergonomics Association / [ed] Lindgaard, G. and Moore, D. (Eds.), Zürich, Switzerland: The International Ergonomics Association , 2015, p. 1-5Conference paper (Refereed)
    Abstract [en]

    The boundary case method is established for the representation and consideration of anthropometric diversity in design tasks with certain characteristics. Sometime boundary cases are defined separately for two distributions, e.g. for females and males, which may lead to a situation where some boundary cases will be redundant in that they are located within the joint distribution rather than on the joint boundary. This paper describes and illustrates a method for automatic identification of redundant boundary cases that are located within two three-dimensional overlapping distributions.

    Practitioner Summary: The paper describes a pragmatic way to focus the design work on users with specific limiting body measurement combinations that can be used to obtain design data or be used to describe appropriate test persons or digital human models for design problems where the boundary case method is suitable.

  • 284.
    Högberg, Dan
    et al.
    University of Skövde, School of Engineering Science.
    Case, Keith
    Loughborough University.
    Supporting 'Design for All' in Automotive Ergonomics2002Conference paper (Refereed)
    Abstract [en]

    The automotive industry faces increasingly tough competition in a global market. One key for competitiveness is product differentiation, in order to attract clearly defined market segments. However, designing cars for specific customer groups incorporates the risk that a car appeals to only a small number of potential buyers. Another issue is that the actual customer group in many cases differs fromthe initially targeted customer group. The use of the ‘design for all’ (DfAll) concept may very well enlarge a car manufacturer’s market and improve the vehicles by making them suit larger populations. This paper discusses the aims of a research project that seeks to identify areas where both the main targeted customer group andothers can gain from a ‘design for all’ approach. Other objectives are to suggest working methods that enable ‘design for all’ in the automotive development process and the identification of computer tools, such as virtual manikins, that can support these objectives early in a virtual design process.

  • 285.
    Högberg, Dan
    et al.
    University of Skövde, School of Engineering Science.
    Case, Keith
    Loughborough University.
    De Vin, Leo J
    University of Skövde, School of Engineering Science.
    Overlapping Ergonomic Evaluation in the Automotive Design Process2002Conference paper (Refereed)
    Abstract [en]

    Ergonomic evaluation typically comes late in the automotive design process, often not performed until physical mock-ups are produced. This may lead to expensive and cumbersome iterations, or to reductions of the final product quality due to low priority of meeting set ergonomic requirements. Computer aided design (CAD) is intensively used for design in the automotive industry. Performance and usability of computers and software are improving at a rapid pace, which enables CAD to be employed even more intensively. This encourages a digital design process where expensive, inflexible and time consuming physical mock-ups are only built at the end of the design process. This incorporates the risk that ergonomic evaluation will be put back even further. A way to address this problem is to enable ergonomics to be evaluated in the digital design process - in a virtual product. However, in many cases, evaluation made in a physical prototype is unbeatable in establishing ergonomic conditions. This paper discusses possible advantages of moving ergonomic evaluation earlier in the automotive design process by implementing planned overlapping strategies. It also shows initial results from a project at a car company, which aims at improving ergonomics integration in the automotive design process, e.g. by looking at task overlapping. These strategies are believed to be applicable both for evaluations made in a virtual environment and evaluations performed in the real world.

  • 286.
    Högberg, Dan
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Hanson, Lars
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Bohlin, Robert
    Fraunhofer-Chalmers Centre.
    Carlson, Johan S.
    Fraunhofer-Chalmers Centre.
    Creating and shaping the DHM tool IMMA for ergonomic product and production design2016In: International Journal of the Digital Human, ISSN 2046-3375, Vol. 1, no 2, p. 132-152Article in journal (Refereed)
    Abstract [en]

    The history, status and outlook of the research and development actions associated with the creation of the digital human modelling tool intelligently moving manikins (IMMA) are described. The underlying fundamental concepts are described and research and development results so far are illustrated or referred to. Two case studies illustrating use of IMMA on industry-based problems are described. The paper also covers reflections on conceptions for prospective DHM tool developments from a general perspective, relating to areas of ergonomics and design methodology, as well as describing some of the plans for further developments and applications of the IMMA tool. These may be of assistance when identifying challenges for future research and development of DHM tools that are used in product and production design processes in industry.

  • 287.
    Högberg, Dan
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Ruiz Castro, Pamela
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Mårdberg, Peter
    University of Skövde, School of Engineering Science. Fraunhofer-Chalmers Centre, Gothenburg.
    Delfs, Niclas
    Fraunhofer-Chalmers Centre, Gothenburg.
    Nurbo, Pernilla
    Volvo Car Corporation, Gothenburg.
    Fragoso, Paulo
    Scania CV, Södertälje.
    Andersson, Lina
    Volvo Trucks, Gothenburg.
    Brolin, Erik
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Hanson, Lars
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    DHM Based Test Procedure Concept for Proactive Ergonomics Assessments in the Vehicle Interior Design Process2018In: Proceedings of the 20th Congress of the International Ergonomics Association (IEA 2018): Volume V: Human Simulation and Virtual Environments / [ed] Sebastiano BagnaraRiccardo TartagliaSara AlbolinoThomas AlexanderYushi Fujita, Cham, Switzerland: Springer, 2018, Vol. 822, p. 314-323Conference paper (Refereed)
    Abstract [en]

    The development of a digital human modelling (DHM) based test procedure concept for the assessment of physical ergonomics conditions in virtual phases of the vehicle interior design process is illustrated and discussed. The objective of the test procedure is to be a valuable tool for ergonomic evaluations and decision support along the design process, so that ergonomic issues can be dealt with in an efficient, objective and proactive manner. The test procedure is devised to support companies in having stable and objective processes, in accordance with lean product development (LPD) philosophies. The overall structure and fundamental functionality of the test procedure concept is explained by a simplified use case, utilizing the DHM tool IPS IMMA to: define manikin families and manikin tasks; predict manikin motions; and visualize simulations and ergonomics evaluation outcomes.

  • 288.
    Igelmo, Victor
    University of Skövde, School of Engineering Science.
    Using a general robot programming system to control an industrial robot2018Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Industrial robot programs are usually created with the programming language that the manufacturer provides. These languages are often limited to cover the common usages within the industry. However, when a more advanced program is needed, then third-party programs are often used to, e.g., locating objects using vision systems, applying correct force with force torque sensors, etc.

    Instead of using both the language of the robot and third-party programs to create more advanced programs, it is preferable to have one system that can fully control the robot. Such systems exist, e.g., Robot Operating System (ROS), Yet Another Robot Language (YARP), etc. These systems require more time to fully set up, but once they are set up supposedly they can be used for a lot of different applications and can be used on several industrial robots from different manufacturers.

    Currently, University of Skövde have robots from Universal Robots (UR) with several peripheral equipment which has limited control because the built-in language does not support it. Therefore, they need help with both investigating which robot system could be used and implementing that robot system.

    This thesis will prove the suitability of using ROS to control aforesaid hardware, fulfilling all the requirements. It will be also demonstrated the feasibility of ROS in the long-term, according to the future plans for this equipment in University of Skövde.

  • 289.
    Inglot, Agnieszka
    et al.
    University of Skövde, School of Engineering Science.
    Franzén, Oskar
    University of Skövde, School of Engineering Science.
    PREVENTION OF WHEEL WEAR, A CASE STUDY: Developing a functioning wheel profile for rail-mounted transportation trolley.2019Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This bachelor’s degree project aimed to improve the wheel profile of a rail mounted trolley and determine the cause of wheel failure. The proceedings of this project where modelled after an approach for solving wear problems with an emphasis on designing for sustainability. A case study and root cause analysis (RCA) was performed and the flanged wheels were deemed insufficient for the given heavy-haul system. Possible areas of wheel profile improvement were identified and further researched with multiple literature reviews. Throughout the projects duration several limitations were introduced that reduced the concept testing to exclusively theoretical prediction models. Archard’s model was implemented to predict wear and operating time for the proposed material and wheel tread profile concepts. The wheel flange dimensions were chosen based on recommendations from wheel and rail interference handbooks among other sources. The final wheel and rail profile suggestion improved operating time by approximately 300% and wear resistance by 50% compared to its predecessor. This result was achieved by applying the same theoretical prediction model to both current and suggested profiles. The findings of this project are meant to aid SCA among others in similar cases and additionally highlight the value of product improvement from a technological, sociological, and environmental perspective.

  • 290.
    Irazu, Aitor
    et al.
    University of Skövde, School of Engineering Science.
    Uranga, Maider
    University of Skövde, School of Engineering Science.
    Design optimisation of a mechanism used to handle heavy objects2019Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This paper presents a design optimisation of a mechanism used to lift and turn heavy objects, in this case, a specific gear that weights 3000 kg. The objective pursued during the development of the project was to reduce the weight of the mechanism, and thus, make it more cost-efficient, as well as to improve the clamping system to secure that the heavy objects are safely handled. The method followed was to first identify the critical parts in cooperation with the client. Then, the corresponding analysis has been developed for each of those parts, by minimising the mass of two of them, and by selecting and dimensioning the guideways for the clamping motion in the other case. The key results obtained from these analyses were that the weight of one of the parts was reduced by 50 %, the clamping system was improved and that the stress analysis shows that the maximum stress is far below acceptable levels. Hence, it is concluded that it was possible to optimise the mechanism and reduce the weight, improving the handling of heavy objects.

  • 291.
    Iriondo, Aitor
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Oscarsson, Jan
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Jeusfeld, Manfred A.
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Simulation Data Management in a Product Lifecycle Management Context2017In: Advances in Manufacturing Technology XXXI: Proceedings of the 15th International Conference on Manufacturing Research, Incorporating the 32nd National Conference on Manufacturing Research, September 5–7, 2017, University of Greenwich, UK / [ed] James Gao, Mohammed El Souri, Simeon Keates, Amsterdam: IOS Press, 2017, p. 476-481Conference paper (Refereed)
    Abstract [en]

    Reuse of virtual engineering models and simulations improves engineering efficiency. Reuse requires preserving the information provenance. This paper suggests a framework based on the 7W data provenance model to be part of simulation data management implemented in product lifecycle management systems. The resulting provenance framework is based on a case study in which a product was re-engineered using finite element analysis.

  • 292.
    Iriondo Pascual, Aitor
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Högberg, Dan
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Kolbeinsson, Ari
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Ruiz Castro, Pamela
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Mahdavian, Nafise
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Hanson, Lars
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. Scania CV, Södertalje, Sweden.
    Proposal of an Intuitive Interface Structure for Ergonomics Evaluation Software2018In: Proceedings of the 20th Congress of the International Ergonomics Association (IEA 2018): Volume VIII: Ergonomics and Human Factors in Manufacturing, Agriculture, Building and Construction, Sustainable Development and Mining / [ed] Sebastiano Bagnara, Riccardo Tartaglia, Sara Albolino, Thomas Alexander, Yushi Fujita, Cham: Springer, 2018, Vol. 825, p. 289-300Conference paper (Refereed)
    Abstract [en]

    Nowadays, different technologies and software for ergonomics evaluations are gaining greater relevance in the field of ergonomics and production development. The tools allow users such as ergonomists and engineers to perform assessments of ergonomic conditions of work, both related to work simulated in digital human modelling (DHM) tools or based on recordings of work performed by real operators. Regardless of approach, there are many dimensions of data that needs to be processed and presented to the users.

    The users may have a range of different expectations and purposes from reading the data. Examples of situations are to: judge and compare different design solutions; analyse data in relation to anthropometric differences among subjects; investigate different body regions; assess data based on different time perspectives; and to perform assessments according to different types of ergonomics evaluation methods. The range of different expectations and purposes from reading the data increases the complexity of creating an interface that considers all the necessary tools and functions that the users require, while at the same time offer high usability.

    This paper focuses on the structural design of a flexible and intuitive interface for an ergonomics evaluation software that possesses the required tools and functions to analyse work situations from different perspectives, where the data input can be either from DHM tools or from real operators while performing work. 

  • 293.
    Iriondo Pascual, Aitor
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Högberg, Dan
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Syberfeldt, Anna
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Brolin, Erik
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Hanson, Lars
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. Scania CV, Södertälje, Sweden.
    Application of Multi-objective Optimization on Ergonomics in Production: A Case Study2020In: Advances in Additive Manufacturing, Modeling Systems and 3D Prototyping: Proceedings of the AHFE 2019 International Conference on Additive Manufacturing, Modeling Systems and 3D Prototyping, July 24-28, 2019, Washington D.C., USA / [ed] Massimo Di Nicolantonio, Emilio Rossi, Thomas Alexander, Springer, 2020, p. 584-594Conference paper (Refereed)
    Abstract [en]

    Taking a holistic perspective is central in production development, aiming to optimize ergonomics and overall production system performance. Hence, there is a need for tools and methods that can support production companies to identify the production system alternatives that are optimal regarding both ergonomics and production efficiency. The paper presents a devised case study where multi-objective optimization is applied, as a step to towards the development of such an optimization tool. The overall objective in the case study is to find the best order in which an operator performs manual tasks during a workday, considering ergonomics and production system efficiency simultaneously. More specifically, reducing the risk of injury from lifting tasks and improving the throughput are selected as the two optimization objectives. An optimization tool is developed, which communicates with a digital human modelling tool to simulate work tasks and assess ergonomics. 

  • 294.
    Izquierdo, Milagros
    et al.
    Department of Mathematics, Linköping University, Linköping, Sweden.
    Stokes, Klara
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Isometric point-circle configurations on surfaces from uniform maps2016In: Symmetries in Graphs, Maps, and Polytopes: 5th SIGMAP Workshop, West Malvern, UK, July 2014 / [ed] Jozef Širáň, Robert Jajcay, Springer, 2016, p. 201-212Chapter in book (Refereed)
    Abstract [en]

    We embed neighborhood geometries of graphs on surfaces as point-circle configurations. We give examples coming from regular maps on surfaces with a maximum number of automorphisms for their genus, and survey geometric realization of pentagonal geometries coming from Moore graphs. An infinite family of point-circle v4 configurations on p-gonal surfaces with two p-gonal morphisms is given. The image of these configurations on the sphere under the two p-gonal morphisms is also described.

  • 295.
    Jacobs, Stephan
    University of Skövde, School of Engineering Science.
    Genetic algorithm for schedule optimization in the homecare industry2018Independent thesis Advanced level (degree of Master (One Year)), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    In the last couple of years, the development within the Artificial Intelligence, AI, has rapidly improved with more and more applications to ease daily live. These applications of AI are countless and can lead to a more sustainable and efficient world. AI is there to solve complex problems which are hard to handle by hand for people and give solutions which would otherwise be not reachable in the same timeframe by considering the same variables. One of the applications of AI is to solve scheduling problems, such as the scheduling optimization problem within the homecare industry. Scheduling within the homecare industry is highly demanding since the problem is very complex due to the many different variables which are dependent on each other. Next to this the industry is dynamic in which members and clients come and go. Within the homecare industry employees, from now on called members, are visiting clients for treatments. These visits are at the clients’ home with a certain length and frequency a week, which is different per client. Next to this a client can have multiple assigned members in which they alternate each other. Next to this the client has his or her private schedule with their availability, which are constraints the schedule maker has to take into account. As an understanding of the problem the case study of Malmo stad is used to receive data and develop an algorithm around. The main objective is to develop a programme which solves the scheduling problem within the homecare industry. For this feasible results are needed which thereby meet the constraints of availability, treatment lengths and frequencies, with high importance of the objective of minimizing the travel time. To get sustainable and efficient schedules the algorithm should find the schedule in which the travel time is the lowest. To address the problem, the research strategy of design and development is used. In this the literature in combination with the case study is used to develop and verify the program Within this project an algorithm is developed on the base of a Genetic Algorithm, GA, within MATLAB. Within the GA the fitness of the individuals is determined by feasibility and if the population has reached the maximum fitness, which is that the schedule is feasible and meets the constraints, goes into a fitness which graded by travel time in which minimum travel time is the most optimum. The programme gives as result the schedule per member within the Area for one week. Overall can be concluded that GA can be a solution to address the scheduling optimization problem for the Homecare industry. The algorithm gives solutions which are sufficient and logic. Nevertheless, with a lack of previous data within the industry and no comparison algorithms the verification of the algorithm is hard. Future work has to determine the performance of the GA with respect to this problem.

  • 296.
    Jalderyd, Emil
    et al.
    University of Skövde, School of Engineering Science.
    Legendi, Linus
    University of Skövde, School of Engineering Science.
    Konstruktion av motoruppkopplingsadapter2019Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The goal of the thesis work is to develop and construct a new solution for connecting engines that goes through a quality check at the testing facility at Volvo Trucks. The thesis work is the final segment of the mechanical engineering program at the University of Skövde.

    Growing demands within manufacturing have led to higher requirements regarding customized products. This puts a higher demand on product variety which leads to greater varieties in production.

    Volvo Trucks manufactures a variety of engines which requires a more flexible way of connecting these different types of engines in the testing facility for testing and quality checks. The current state of this connection is inadequate, improvised and non-flexible. Volvo Trucks have expressed a wish to improve the quality- and testing process regarding the exhaust connection of the engines, as Volvo Trucks are planning a future reconstruction of the testing facility.

    The project started by performing an extensive literature review to investigate how variety in production and demands for a more flexible connection can be solved through product design. The variations that affected the connection between the different motor types and the testing facility were documented and used as a foundation for further work.

    A number of concepts regarding the handling of the different motor types were developed and reviewed with 3D-printed prototypes. A final concept was calculated, dimensioned and constructed. The result shows that it is possible to handle the vast variation in production with the help of robust design. The result also showed that the present connections are oversized and insufficient.

    The authors of this report recommend that Volvo Trucks should continue with implementing the new connection in production to perform tests and develop this connection further.

  • 297.
    Jiang, Yuning
    et al.
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Atif, Yacine
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Ding, Jianguo
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Wang, Wei
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    A Semantic Framework With Humans in the Loop for Vulnerability-Assessment in Cyber-Physical Production Systems2019Conference paper (Refereed)
    Abstract [en]

    Criticalmanufacturingprocessesinsmartnetworkedsystems such as Cyber-Physical Production Systems (CPPSs) typically require guaranteed quality-of-service performances, which is supported by cyber- security management. Currently, most existing vulnerability-assessment techniques mostly rely on only the security department due to limited communication between di↵erent working groups. This poses a limitation to the security management of CPPSs, as malicious operations may use new exploits that occur between successive analysis milestones or across departmental managerial boundaries. Thus, it is important to study and analyse CPPS networks’ security, in terms of vulnerability analysis that accounts for humans in the production process loop, to prevent potential threats to infiltrate through cross-layer gaps and to reduce the magnitude of their impact. We propose a semantic framework that supports the col- laboration between di↵erent actors in the production process, to improve situation awareness for cyberthreats prevention. Stakeholders with dif- ferent expertise are contributing to vulnerability assessment, which can be further combined with attack-scenario analysis to provide more prac- tical analysis. In doing so, we show through a case study evaluation how our proposed framework leverages crucial relationships between vulner- abilities, threats and attacks, in order to narrow further the risk-window induced by discoverable vulnerabilities.

  • 298.
    Johansson, Gustav
    et al.
    University of Skövde, School of Engineering Science.
    Karlsson, Emelie
    University of Skövde, School of Engineering Science.
    Utveckling av fäste och skyltar för bakrutetorkare på personbilar2019Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis discloses a bachelor degree project in Product Design Engineering at the University of Skövde. The project was performed in collaboration with a company called The Best of Sweden AB where the assignment was to develop a universal mount and signs for rear window wipers on cars.

    The development process started with a prestudy where customer needs where analyzed. Different factors which affect the product in the environment of use, such as the aerodynamics of cars and the force in the rear window wiper engine, were examined as well during the prestudy. A field study was carried out on existing rear window wipers which became the basis of the dimensions of the signs as well as the mount. The result of the pilot study ended in a list of requirements that the final concept was to be compared to. Different structured design methods was used during concept generation as well as concept evaluation which was followed by a development of the details of the final concept. A proposition of material selection and manufacturing method was determined as well as an estimation of manufacturing cost.

    The result was a fastening device and signs for rear window wipers on cars which makes it possible for the user to mount personalized signs if various different formats. The fastening device consists of a base mount and a strap, where the strap is tightened around the rear window wiper and keeps the base mount in place. The symmetry of the product enables it to be mounted to a rear window wiper that either rotates clockwise or counter-clockwise.

  • 299.
    Johansson, Marcus
    et al.
    University of Skövde, School of Engineering Science.
    Nilsson, Jacob
    University of Skövde, School of Engineering Science.
    Virtuell driftsättning: Verifiering av PLC logik mot simuleringsprogram2015Independent thesis Basic level (university diploma), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    To shorten project lead times Volvo Cars Skövde decided to explore the possibilities regarding verifi-cation of PLC-logic in simulation programs. The overall objective of the thesis was to analyze the pos-sibilities for establishing communication between the flow simulation program Plant Simulation and a PLC-device. A thorough understanding of the area virtual commissioning was obtained by writing the frame of reference and a literature review which served as basis for the continued practical work. Through a collection of interviews, discussions and an extensive literature review a better under-standing regarding how the communication between the different programs works, along with im-portant points that should be considered under a virtual commissioning project was obtained. A hy-pothetical system was developed in Plant Simulation by Volvo Cars Skövde to be used as a test sys-tem. The Simumatik3D model was created by emulating the Plant Simulation model and at the same time developing the PLC-logic in Siemens Step 7. During the development progress subsystems were verified in Simumatik3D against the created PLC-logic until the model was fully developed. To make sure that both the Simumatik3D model and the Plant Simulation model was valid a number of valida-tion points were tested. After the validation test the experimental phase started were different sce-narios were analyzed and tested to bring up any problems in the models to the surface. A thorough evaluation is presented in which the entire construction phase of the models is evaluated in terms of time required, advantages and disadvantages and communication with the PLC-device. The two pro-grams Simumatik3D and Plant Simulation was evaluated against one another in order to find out which program that is the most suited for virtual verification of PLC-logic. An overall methodology was developed based on the evaluation carried out and the experience gained from the implementa-tion of the work. The result from the developed methodology is presented which describes the parti-tion between the client and supplier, the communication between them and a visualization of the methodology-process. The result from the evaluation showed that Simumatik3D was more suitable for verification of PLC logic on a detailed level. The evaluation also showed that the PLC logic could be verified with Plant Simulation, but not on the same detailed level. Plant Simulation was more suit-able for making simulation models more realistic. Virtual commissioning of PLC-logic is a new con-cept on Volvo Cars Skövde and therefore can the result from this thesis form a basis for future work in this area. Virtual verification of PLC-logic is discussed in which several important aspects to think about is presented. The projects main goal to virtually verify PLC-logic in simulation programs was achieved and yielded good results, the partial objectives resulted in a thorough evaluation and future recommendations.

  • 300.
    Johansson, Mattias
    et al.
    University of Skövde, School of Engineering Science. matte_j96@hotmail.com.
    Wirdelius, Oscar
    University of Skövde, School of Engineering Science. oscar.wirdelius@gmail.com.
    Utveckling av ett växthus för inom- och utomhusbruk2018Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The degree project’s purpose was to develop a product following a methodological approach. The product was a miniature greenhouse for indoor and outdoor use, commissioned by a company. The goal of the project was to develop an entire product. An extensive prestudy was performed focused on understanding plants and their needs. Wishes and demands of users were collected by questionnaires and interviews. The answers collected became the basis for many decisions regarding function and form. Furthermore, a lot of focus was on developing a trendy and sustainable product. The development process followed Pahl and Beitz’s model which consists of 4 phases: Planning/specification, Conceptual design, Concept development and Detail design.

    The result is a greenhouse with the possibility for growing in pots or soil. The lid acts as a storage space and encapsulates the synthetic lights that will help the plants grow, especially in climates with less sun. The lid also contains a system that makes watering the plants easier. The modular construction gives the user 360-degree access to the plants from soil level.

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