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  • 251.
    Fröjd, Felix
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Kovacevic, Mate
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Konstruktion av testrigg för taktrycksprov2020Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Every year, thousands of people are killed in car crash accidents. A commonly occurring accident with a potentially fatal outcome is the so called "roll-over accidents" when a vehicle rolls over on its roof and the roof gets pressed in towards the driver or passenger. To decrease injuries and deaths from roll-over accidents, there is a federal law called FMVSS 216a that car manufacturers need to stay within. This law describes the minimum roof strength of a vehicle relative to its weight. To insure themselves that they follow this law, car manufacturers need to test their vehicles roof strength. To enable this, they need a special test equipment with specific instructions from FMVSS 216a. National Electric Vehicle Sweden is a company located in the previous facilities of Swedish car manufacturer SAAB in Trollhättan, Sweden. They are in the need of a new roof strength test rig because their existing test rig does not correspond to the federal regulations of FMVSS 216a. There are a few roof strength test rigs on the market that can be bought and corresponds to the regulations of FMVSS 216a. These can also be examined to be inspired by and compared with. A variety of structural components will be constructed and compiled in CAD. These will also be simulated with FEA to ensure that the rig stays within the tolerances stated by the regulations. The structural components will also make motions and movements made by functional components. These components will be investigated and selected by suitable suppliers and placed in the compilation. This thesis has resulted in a design proposal for a roof strength test rig that comply with the laws and requirements set by FMVSS 216a. It can also perform tests according to IIHS Roof Strength Safety Protocol v.III and has also been provided with angle adjustments that enable other types of tests.

  • 252.
    Fuente, Raquel
    et al.
    IK4-LORTEK, Ordizia, Spain.
    García de la Yedra, Aitor
    IK4-LORTEK, Ordizia, Spain.
    Beizama, Ane Miren
    IK4-LORTEK, Ordizia, Spain.
    Fernández, Erik
    IK4-LORTEK, Ordizia, Spain.
    Gorostegui Colinas, Eider
    IK4-LORTEK, Ordizia, Spain.
    Echeverria, Alberto
    IK4-LORTEK, Ordizia, Spain.
    Broberg, Patrik
    University West, Department of Engineering Science, Division of Automation Systems.
    Thorpe, Nigel
    Tecnitest ingenieros, Madrid, Spain.
    Runnemalm, Anna
    University West, Department of Engineering Science, Division of Automation Systems.
    Henrikson, Per
    GKN Aerospace Engine Systems Sweden, Trollhättan, Sweden.
    Development and demonstration of an automated system for limited access weld inspection by using infrared active thermography2015In: Proceedings 7th International Symposium on NDT in Aerospace, Berlin, 2015, p. 1-8Conference paper (Refereed)
    Abstract [en]

    Weld inspection for surface breaking defects detection has been traditionally performed by using NDT methods such as Fluorescent PenetrantInspection (FPI), Visual Inspection (VI) or Eddy Currents (EC). All those well known techniques have as common drawback the need of skilled operator intervention in order to analyse obtained results. In the specific case of inspection of welds with limited access, the application of those traditional methods is even more complex, thus increasing inspection time and reducing the defect detection capability. Therefore, the development of a fully automated non-contact method overcoming these limitations is desired. Active thermography (IRT) represents one of the most promising techniques for replacing traditional techniques for surface breaking defect detection in welds.This technique makes use of an excitation source in order to heat the sample undertest and an infrared camera for thermal evolution monitoring. With the combination of these excitation-monitoring techniques, heterogeneities in the heat flow caused bysurface breaking cracks can be detected. In this work, a robotic solution was developed and demonstrated for the inspection of welds with real cracks in a representative environment with limited access. The system consists of a continuous laser-line excitation source together with a FLIR SC 655 micro bolometer thermographic camera. In order to access limited areas, two different aluminium polished mirrors have been used for bothinfrared radiation monitoring and laser excitation respectively. The inspection results, analysis and comparison with traditional methods will be shown.

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  • 253.
    Galloway, Rory
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Linde, Albin
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Skillnader i rörliga kostnader i relation till variationer i produktiviteten: en systemstudie2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Nouryon is global company that produces specialty chemicals. Their products come into use in many everyday applications. This project is carried out in one of Nouryons factories located in Stenungsund. Nouryon in Stenungsund is divided into two business units, Functional Chemicals and Surface Chemistry. The area to be investigated in this project is Surface Chemistry where it has been noted that variations in productivity within the variable costs differ between 2018 and 2019.

    The purpose of the thesis is to investigate, create an understanding and find reasons to why variation of productivity has occurred within the company between 2018 and 2019. The goal is to create an understanding of how the program, SAAG, site at a glance, measures productivity and variable manufacturing cost, and that the purpose should form the basis for designing relevant and achievable improvement proposals to reduce the variations that has been noted.

    In the thesis a literature study was conducted, where theories linked to the field would create a foundation and understanding of the subject. The subjects include, productivity, variable manufacturing cost, lean and sustainability. The literature study along with the methods form the basis for the work to be developed in a structed way. Under the title, results, an analysis of the current situation. The analysis of the current situation led to a more visible and clear understanding of what the problem was and the extent of it. This led to further research into the various sources of error, which the current status analysis showed, to find the underlying causes for the variations.

    The study concluded that the difference in strategy of the company between 2018 and 2019 led to the majority of varying productivity, as well as problems that arose in 2018 that where not sorted during that calendar year, but instead where sorted in 2019, which first during the sortingprocess results in a variation of productivity within the manufacturing cost to vary. Furthermore, Nouryon should continue its research within the topic to see changes and to be able react quickly to changes with in this subject

  • 254.
    Gamble, Julia
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Simonsson, Oscar
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Sustainability and Circular Economy of Powder Based Additive Manufacturing2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Additive manufacturing (AM) is an advanced manufacturing technology with many potential sustainability benefits, especially in the aerospace industry. This includes the possibilities to produce complex lightweighted (hollow) components, reducing fuel consumption for aircrafts. Outside of the use phase, there are still challenges to overcome in terms of understanding environmental and sustainability benefits. The purpose of this study was to investigate the life cycle properties and compile findings regarding AM of metal components, in order to assess its impact on the environment and sustainability. This includes an overview of AM, a quantitative life-cycle investigation of superalloy IN718 and a qualitative sustainability assessment of AM using Ashby's five-step method and a discussion in terms of Circular Economy. Results from a life-cycle inventory (LCI) show that both AM-methods, electron beam melting and selective laser melting in this case, required significant specific energy in manufacturing (including powder production), comparable to the embodied energy of the raw material itself. The energy-use is highly dependent on the geometry of the build though and AM offers many advantages in all three sustainability dimensions. This is, amongst other things, due to potential in material savings and closing material loops, freedom in design, on-demand production as well as possibilities for repair and refurbishment. Results also showed that AM have opportunities for better material efficiency than conventional methods, in a circular economy model. One conclusion was that AM-technologies, due to slow build time and relatively high energy consumption (depending on geometry), is not yet feasible for mass production but rather suits small batches of customized or complex components.

  • 255.
    Ganvir, Ashish
    University West, Department of Engineering Science, Division of Manufacturing Processes. University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Comparative analysis of Thermal Barrier Coatings produced using Suspension and Solution Precursor Feedstock2014Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The research work performed in this thesis has been carried out at the Production Tech-nology Centre where the Thermal Spray research group of University West has its work-shop and labs.

    This research work has been performed in collaboration with the International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), Hyderabad, India.

    First of all, I would like to express my sincere thanks and gratitude to my supervisors Dr. Nicolaie Markocsan and Dr. Nicholas Curry for their guidance, great support and valuable suggestions without which this work could not have been possible. I would also like to thanks Prof. Per Nylén for keeping faith in me and providing me an opportunity to work at PTC, which is a great place to perform research. It is my pleasure being their student and I wish I would keep learning from all of them, both on academic and personal grounds. I would also like to thank my colleagues at PTC Mr. Mohit Gupta and Mr. Stefan Björklund, for their help and support during this work.

    I would like to acknowledge the H.C. Starck Company for its financial support for the pro-ject; Dr. Filofteia-Laura TOMA at Fraunhofer IWS, Dresden to help us in spraying suspen-sion sprayed YSZ top coats, G Shivkumar from ARCI to help us in spraying solution pre-cursor sprayed top coats and Toni Bogdanoff, Jönköping University to help us in conduct-ing the LFA experiment

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  • 256.
    Ganvir, Ashish
    et al.
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Goel, Sneha
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Govindarajan, Sivakumar
    International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), 500005 Hyderabad (IND).
    Jahagirdar, Adwait Rajeev
    University West, Department of Engineering Science.
    Björklund, Stefan
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Klement, Uta
    Chalmers University of Technology, Gothenburg, (SWE).
    Joshi, Shrikant V.
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Tribological performance assessment of Al2O3-YSZ composite coatings deposited by hybrid powder-suspension plasma spraying2021In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 409, p. 1-13, article id 126907Article in journal (Refereed)
    Abstract [en]

    The advent of high-throughput plasma spray systems that allow axial feeding encourages the study of using liquid feedstock for various next-generation functional applications. The current study explores the benefit of such a plasma spray system to deposit hybrid powder-suspension Al2O3-YSZ ceramic matrix composite (CMC) coatings for tribological applications. The tribological performance of the hybrid processed CMC coatings was assessed using scratch, ball-on-plate wear and erosion tests and compared with that of monolithic powder-derived Al2O3 coatings. As-deposited and tribo-tested coatings were characterized using Scanning Electron Microscopy, X-ray Diffraction and Energy Dispersive Spectroscopy to analyse their microstructure and phase constitution. The results showed that the tribological performance of the hybrid powder-suspension Al2O3-YSZ CMC coating was significantly improved by enhancing the wear resistance under scratch, dry sliding ball-on-plate and erosion tests as compared to the conventional APS deposited monolithic Al2O3 coating. About 36% decrease in the dry sliding ball-on-plate specific wear rate and up to 50% decrease in the erosion wear rate was noted in the hybrid powder-suspension Al2O3-YSZ CMC coating as compared to the conventional APS deposited monolithic Al2O3 coating. The study concludes that the hybrid powder-suspension route can create CMC coatings with unique multi-length scale microstructures which can be attractive for combining different tribological attributes in the same coating system.

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  • 257.
    Gao, Jiaming
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Industrial robot motion control for joint tracking in laser welding2016Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Laser welding is used in modern industrial production due to its high welding speed and good welding performance comparing to more traditional arc welding. To improve the flex-ibility, robots can be used to mount the laser tool. However, laser welding has a high require-ment for the accuracy in positioning the laser tool. There are three main related variables which affect the laser welding accuracy: robot path accuracy, workpiece geometry and fixture repeatability. Thus, joint tracking is very important for laser welding to achieve high quality welds.

    There are many joint tracking systems which were proposed in recent years. After receiv-ing the joint information, a control system is necessary to control the robot motion in real-time. The open control system for the industrial robot is one trend for the future. A lot of methods and systems are proposed to control the robot motion. Some systems can achieve a high accuracy in the experiments. However, it is still hard to apply them in practical indus-trial production. Thus more commercial solutions appear to overcome the robot motion problem nowadays. They are very useful to realize practical applications.

    ABB EGM path correction module, a new function of Robotware, is one of the com-mercial solutions for robot motion control in real time. In the experiments presented in this work, a computer is used to simulate a sensor to create a path correction signal.

    To test its feasibility for the laser welding application, many experiments are conducted. One was to test the robot path repeatability when there is no correction message sent to the robot. Another was to test the level of accuracy EGM can achieve during the correction process. Different types of paths and three different speeds were separately carried out. The results showed that it is possible to use the EGM in the laser welding application. In the EGM feasibility test, there exists deviation in the z-direction. Since these deviations are less than 0.2mm, it will have a minor influence the laser welding performance, implying that the EGM path correction can be applied in practical production.

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  • 258.
    Garcia de la Yedra, Aitor
    et al.
    Control and Evaluation, IK4-LORTEK; Arranomendia Kalea 4A, Ordizia, Spain.
    Fernandez, Erik
    Control and Evaluation, IK4-LORTEK; Arranomendia Kalea 4A, Ordizia, Spain.
    Beizama, Ane Miren
    Control and Evaluation, IK4-LORTEK; Arranomendia Kalea 4A, Ordizia, Spain.
    Fuente, R.
    Control and Evaluation, IK4-LORTEK; Arranomendia Kalea 4A, Ordizia, Spain.
    Echeverria, A.
    Control and Evaluation, IK4-LORTEK; Arranomendia Kalea 4A, Ordizia, Spain.
    Broberg, Patrik
    University West, Department of Engineering Science, Division of Automation Systems.
    Runnemalm, Anna
    University West, Department of Engineering Science, Division of Automation Systems.
    Henrikson, Per
    GKN Aerospace Engine Systems.
    Defect strategies in Nickel Superalloys weld using active thermography2014In: 12th International Conference on Quantitative InfraRed Thermography, 7-11/7 Bordeaux, 2014, p. 1-9Conference paper (Refereed)
    Abstract [en]

    As a result of extreme operation conditions in gas turbines, high resistance materials with excellent behaviour at high temperature are required. Alloys, such as MarM-247 nickel based superalloy, with excellent mechanical properties at very high temperature (even at 85 % of their melting point) are being used in these applications. This extraordinary behaviour is mainly due to the presence of a strengthening phase (γ’) with the following chemical composition: Ni3(Al, Ti). However, during welding these materials are susceptible to cracking and this is why weld inspections become crucial. In this work different strategies for defect detection in welds are introduced, all of them based on active thermography. The work covers aspects such as different excitation and data evaluation strategies.

  • 259.
    Garcia Reyes, Sergio
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Unidirectional force sensor2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project aims to develop a force sensor, which one should measure the load applied to on the top of the platform. This load is going to be a horizontal force with a limit value of ±3000N.

    The study aims to figure out how to develop this project and make it, this project was planned and executed according to circumstances created by COVID-19. The first step is to select the strain gauges that are going to be used and the type of Wheatstone bridge. After the Wheatstone bridge, the signal must be amplified and then registered and presented to the computer.

    To reach this a lot of books and articles have been studied. For the realization of this project have been used 3 software. First, Multisim which has been used to simulate the Wheatstone bridge and know what the voltage at the output of the circuit would be. The second is the NX FEM by Siemens, which was used to send the simulation of the platform and thus see results as deformation. Finally, Abaqus has also been used to make a 2D prototype and, like the previous one, to see the deformations in the platform. Due to the COVID-19, the assembly of the device has been impossible to carry out. Despite this, all the theoretical part has been carried out and also guidelines how to fit the strain gauges. It has been tried to do as much as possible and it has been explained as far as possible the steps that should be followed to assemble the device. Therefore, even if the practical part cannot be done, the device should be able to be perfectly assembled simply by following the instructions.

  • 260.
    Garis, David
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Hagren, Jesper
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Förbättring av det ekologiska hållbarhetsarbetet för tjänsteföretag inom el- och automationsindustrin2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is done with the purpose to examine how service companies in the electric-and automation branch can act within the field of ecological sustainability. The survey was conducted through a literature review and a case study in which a specific company and their customers were mapped. The target is to present improvement suggestions that can be helpful in both companies' internal work, but also how they can work with their customers to improve their work on ecological sustainability together. The case study is limited to examining only three of the company's customers.

    The work began with a literature review being carried out by gathering information from mainly books, articles, and web pages to get a general overview of the methods and processes that companies can use. A case study was then conducted based on semi-structured interviews with the company and its customers to get a clear picture of how the work on ecological sustainability can look in reality.

    By screening the literature review and the case study, it became clear that the most important parts of a company's work on ecological sustainability is to map its aspects in order to create a correct understanding of how the business affects the environment. Furthermore, it turned out that circular economy is a subject that the investigated company's customers are working a lot today but believe that still has great potential. Finally, it was noted that service companies are an important part of their customers' environmental work and have the greatest chance of influencing it in the costumers' core process.

    With the result of the review as a basis, three improvement proposals were formed. The first one is more comprehensive and focuses on how service companies can work strategically with ecological sustainability internally. The other two focus on collaboration with their customers. The improvement proposals are described as follows:

    1. Establish strategic improvement efforts for ecological sustainability

    2. Customer link focusing on ecological sustainability

    3. Reuse of equipment

  • 261.
    Garis, David
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Hagren, Jesper
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Förbättring av det ekologiska hållbarhetsarbetet för tjänsteföretag inom el- och automationsindustrin2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is done with the purpose to examine how service companies in the electric-and automation branch can act within the field of ecological sustainability. The survey was conducted through a literature review and a case study in which a specific company and their customers were mapped. The target is to present improvement suggestions that can be helpful in both companies' internal work, but also how they can work with their customers to improve their work on ecological sustainability together. The case study is limited to examining only three of the company's customers. The work began with a literature review being carried out by gathering information from mainly books, articles, and web pages to get a general overview of the methods and processes that companies can use. A case study was then conducted based on semi-structured interviews with the company and its customers to get a clear picture of how the work on ecological sustainability can look in reality. By screening the literature review and the case study, it became clear that the most important parts of a company's work on ecological sustainability is to map its aspects in order to create a correct understanding of how the business affects the environment. Furthermore, it turned out that circular economy is a subject that the investigated company's customers are working a lot today but believe that still has great potential. Finally, it was noted that service companies are an important part of their customers' environmental work and have the greatest chance of influencing it in the costumers' core process. With the result of the review as a basis, three improvement proposals were formed. The first one is more comprehensive and focuses on how service companies can work strategically with ecological sustainability internally. The other two focus on collaboration with their customers. The improvement proposals are described as follows: 1. Establish strategic improvement efforts for ecological sustainability 2. Customer link focusing on ecological sustainability 3. Reuse of equipment

  • 262.
    Gharaibeh, Lina
    et al.
    University West, Department of Engineering Science, Division of Production Systems.
    Eriksson, Kristina M.
    University West, Department of Engineering Science, Division of Production Systems.
    Lantz, Bjorn
    University West, Department of Engineering Science, Division of Production Systems.
    Matarneh, Sandra
    Al-Ahliyya Amman University (JOR).
    Elghaish, Faris
    Queen's University Belfast, Belfast, (GBR).
    Towards digital construction supply chain-based Industry 4.0 solutions: scientometric-thematic analysis2022In: Smart and Sustainable Built Environment, ISSN 2046-6099, E-ISSN 2046-6102Article in journal (Refereed)
    Abstract [en]

    Purpose – The wood construction industry has been described as slow in adapting efficiency-increasingactivities in its operations and supply chain. The industry is still facing challenges related to digitalization, suchas fragmentation, poor traceability and lack of real-time information. This study evaluates the status ofdigitalization in construction supply chains by thematically analyzing the existing literature and mappingresearch trends.Design/methodology/approach – A review of the key literature from 2016 to 2021 was performed. Theresults highlight various technologies and their applications within supply chains and identify research gaps,especially between theoretical frameworks and actual implementation using a scientometric-thematic analysis.Findings – This paper provides a conceptual framework to further aid researchers in exploring the currenttrends in Supply Chain 4.0 and its applications in the wood construction industry compared to other moreadvanced industries. Suggested directions for future research in the wood construction Supply Chain 4.0 areoutlined.Originality/value – The existing literature still lacks a comprehensive review of the potential of a digitalizedsupply chain, especially in the construction industry. This framework is pivotal to continue explaining andobserving the best ways to accelerate and implement Supply Chain 4.0 practices for digitalized supply chainmanagement (SCM) while focusing specifically on the wood construction industry. The literature review resultswill help develop a comprehensive framework for future research direction to create a clearer vision of thecurrent state of digitalization in supply chains and focus on the wood construction supply chain, thus, fullyachieving the benefits of Supply Chain 4.0 in the wood construction industry.

  • 263.
    Gharaibeh, Lina
    et al.
    University West, Department of Engineering Science, Division of Production Systems.
    Eriksson, Kristina M.
    University West, Department of Engineering Science, Division of Production Systems.
    Lantz, Björn
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering. University West, Department of Engineering Science, SE-461 86 Trollhättan, Sweden.
    Supply Chain Digitalization in the Wood Manufacturing Industry: A Bibliometric Literature Review2022In: Advances in Transdisciplinary Engineering, ISSN 2352-751X, Vol. 21, p. 617-628Article in journal (Refereed)
    Abstract [en]

    Abstract. The wood manufacturing industry has been described as slow in adopting

    efficiency increasing activities in its operations and supply chain, the industry is still

    facing challenges relating to digitalization such as fragmentation, poor traceability,

    and lack of real-time information. The integration of industry 4.0 technologies can

    enhance the supply chain performance in terms of efficiency, collaboration, quality,

    and transparency. This paper aims to evaluate the current status of digitalization in

    supply chains, by analysing the existing literature and mapping research trends. in an

    aim to create a clearer vision of the current state of digitalization in supply chains in

    general and focusing on the wood manufacturing supply chain in particular, the

    results of the literature review will be used to develop a comprehensive framework

    for future research direction, to fully achieve the benefits of supply chain 4.0 in the

    wood manufacturing industry. This framework serves as a departure point to continue

    explaining and observing the best way to accelerate and implement Supply Chain 4.0

    practices for digitalized supply chain management while focusing specifically on the

    wood manufacturing industry. To achieve the overall purpose, a literature review of

    the key literature from 2016 to 2021 has been performed. using a bibliometric and

    content review analysis, the results shed light on various technologies and their

    applications within supply chains and identify research gaps especially between

    theoretical frameworks and actual implementation. This paper provides a conceptual

    framework to further aid researchers in the exploration of knowledge regarding the

    most current trends in Supply Chain 4.0 and its applications in the wood

    manufacturing industry compared to other advanced industries, as well as the

    directions of the new research in the wood manufacturing Supply Chain 4.0.

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  • 264.
    Gimmerthal, Marlo
    et al.
    University West, Department of Engineering Science.
    Sennert, Bastian
    University West, Department of Engineering Science.
    Development and implementation of an automatic testing procedure in accordance with Automotive SPICE for control units2023Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The goal of the present paper is to deliver a proof of concept for an automized testing procedure of a control unit in accordance with the Automotive SPICE framework. 

    Therefore, a concept and a strategy to automate the exchange of data (e.g. system requirements, test case requirements, testing results) between Siemens Polarion as requirements management tool and vTESTstudio as test management system has been developed. 

    The defined testing strategy was implemented into a software for test automation (vTESTstudio/CANoe). This software was then connected to the requirements management software for documentation purposes to satisfy the requirements of the Automotive SPICE framework. 

    A wide range of control units can be used as test target within a Vector VT-system hardware-in-the-loop (HIL) setup. The loads or sensors to the control unit can be either real or simulated in the HIL test stand. 

    The ultimate goal to run all pre-defined tests as implemented in the software on a control unit was met. Afterwards, the results of each individual test were successfully recorded and exchanged into in the requirements management software to get full traceability between requirement and test result. 

    The successful proof of concept can serve as platform for process automation in automotive or offroad testing environments. As a result, this helps to increase efficiency in prototype testing in terms of personnel as well as capital expenses. 

  • 265.
    Gislén, Linda
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Alternative design of robot cell concepts for flexible production2016Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Flexible manufacturing is something that most companies is aiming to accomplish due to the increased demand for variety and a competitive global market.

    This thesis report includes an introduction to the automation concept and the development towards flexible automation. A general flexible assembly cell is presented and its content and requirements are discussed. The work has been done with focus on an assembly process with dedicated fixtures at VCE (Volvo Construction Equipment).

    Based on the literature review and the general example, a list of actions to take while planning and implementing a process is developed. The actions roughly include: mapping of the process, defining goals, investigation of automation level, holistic view while planning, definition of the need for flexibility, investment plan, designing and comparing concepts, investigation of possible issues and implementation in small scale.

    The current manual process at VCE is presented and analysed. Three concepts are designed with product flexibility as an alternative to processes in which traditional dedicated fixtures are used. The designed concepts are a fully automated concept, a hybrid concept with separated workspace and a human-robot collaboration.

    Finally, the concepts are analysed and compared based on following parameters: productivity, product cost, investment, flexibility, space requirement and setup time. One final comparing summary of the concepts is done. The analysis shows that a fully automated concept is to prefer in this case. However, a human-robot collaboration could be appropriate to use if the process is expected to improve with the human workforce. Examples of when it could be reasonable to use human-robot collaboration despite this are: if the task provides better quality when conducted by human or if the task is complex to automate.

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  • 266.
    Gislén, Linda
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Agell, Ulrica
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Flödesanalys av orderhantering vid SKF Logistics Services Sweden2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of the thesis is to provide SKF Logistics Services Sweden, within Customer Services and Warehousing, with an analysis of the actual process and improvement suggestions to reduce late invoicing. The objective of the thesis contain a mapping of the process, identified parameters that affect late invoicing, reduce non-value added activities and improvement proposals to keep the internal invoice deadline.According to DMAIC, which was used as a method to analyse the qualitative and quantitative data, the most broken deadlines occur to the container traffic. That became the focus of the investigation. Further analysis led to the conclusion that the orders are not packed by Warehousing on time. It was decided to address that as a main problem to improve on.Quality tools were used to find root causes and improvements. The improvements were evaluated and two main improvements were chosen. Organisational improvements on how to work with process improvements are proposed. It contain working with PDCA, standardisation, decision making and measurements. A process improvement for Warehousing are proposed which contain segmentation of articles, letting the bottleneck limit the throughput and prioritisation of assignments.

  • 267.
    Glorieux, Emile
    University West, Department of Engineering Science, Division of Automation Systems.
    Constructive cooperative coevolution for optimising interacting production stations2015Licentiate thesis, monograph (Other academic)
    Abstract [en]

    Engineering problems have characteristics such as a large number of variables, non-linear, computationally expensive, complex and black-box (i.e. unknown internal structure). These characteristics prompt difficulties for existing optimisation techniques. A consequence of this is that the required optimisation time rapidly increases beyond what is practical. There is a needfor dedicated techniques to exploit the power of mathematical optimisation tosolve engineering problems. The objective of this thesis is to investigate thisneed within the field of automation, specifically for control optimisation ofautomated systems.The thesis proposes an optimisation algorithm for optimising the controlof automated interacting production stations (i.e. independent stations thatinteract by for example material handling robots). The objective of the optimisation is to increase the production rate of such systems. The non-separable nature of these problems due to the interactions, makes them hard to optimise.The proposed algorithm is called the Constructive Cooperative CoevolutionAlgorithm (C3). The thesis presents the experimental evaluation of C3, bothon theoretical and real-world problems. For the theoretical problems, C3 istested on a set of standard benchmark functions. The performance, robustness and convergence speed of C3 is compared with the algorithms. This shows that C3 is a competitive optimisation algorithm for large-scale non-separable problems.C3 is also evaluated on real-world industrial problems, concerning thecontrol of interacting production stations, and compared with other optimisation algorithms on these problems. This shows that C3 is very well-suited for these problems. The importance of considering the energy consumption and equipment wear, next to the production rate, in the objective function is also investigated. This shows that it is crucial that these are considered to optimise the overall performance of interacting production stations.

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  • 268.
    Glorieux, Emile
    University West, Department of Engineering Science, Division of Production Systems.
    Multi-Robot Motion Planning Optimisation for Handling Sheet Metal Parts2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Motion planning for robot operations is concerned with path planning and trajectory generation. In multi-robot systems, i.e. with multiple robots operating simultaneously in a shared workspace, the motion planning also needs to coordinate the robots' motions to avoid collisions between them. The multi-robot coordination decides the cycle-time for the planned paths and trajectories since it determines to which extend the operations can take place simultaneously without colliding. To obtain the quickest cycle-time, there needs to bean optimal balance between, on the one hand short paths and fast trajectories, and on the other hand possibly longer paths and slower trajectories to allow that the operations take place simultaneously in the shared workspace. Due to the inter-dependencies, it becomes necessary to consider the path planning, trajectory generation and multi-robot coordination together as one optimisation problem in order to find this optimal balance.This thesis focusses on optimising the motion planning for multi-robot material handling systems of sheet metal parts. A methodology to model the relevant aspects of this motion planning problem together as one multi-disciplinary optimisation problem for Simulation based Optimisation (SBO) is proposed. The identified relevant aspects include path planning,trajectory generation, multi-robot coordination, collision-avoidance, motion smoothness, end-effectors' holding force, cycle-time, robot wear, energy efficiency, part deformations, induced stresses in the part, and end-effectors' design. The cycle-time is not always the (only) objective since it is sometimes equally/more important to minimise robot wear, energy consumption, and/or part deformations. Different scenarios for these other objectives are therefore also investigated. Specialised single- and multi-objective algorithms are proposed for optimising the motion planning of these multi-robot systems. This thesis also investigates how to optimise the velocity and acceleration profiles of the coordinated trajectories for multi-robot material handling of sheet metal parts. Another modelling methodology is proposed that is based on a novel mathematical model that parametrises the velocity and acceleration profiles of the trajectories, while including the relevant aspects of the motion planning problem excluding the path planning since the paths are now predefined.This enables generating optimised trajectories that have tailored velocity and acceleration profiles for the specific material handling operations in order to minimise the cycle-time,energy consumption, or deformations of the handled parts.The proposed methodologies are evaluated in different scenarios. This is done for real world industrial case studies that consider the multi-robot material handling of a multi-stage tandem sheet metal press line, which is used in the automotive industry to produce the cars' body panels. The optimisation results show that significant improvements can be obtained compared to the current industrial practice.

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  • 269.
    Glorieux, Emile
    et al.
    University West, Department of Engineering Science, Division of Automation Systems.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Automation Systems.
    Svensson, Bo
    University West, Department of Engineering Science, Division of Automation Systems.
    Lennartson, Bengt
    University West, Department of Engineering Science, Division of Automation Systems. University West, Department of Engineering Science, Division of Production Systems. Chalmers University of Technology, Department of Signals and Systems, Gothenburg, Sweden.
    Constructive cooperative coevolutionary optimisation for interacting production stations2015In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 78, no 1-4, p. 673-688Article in journal (Refereed)
    Abstract [en]

    Optimisation of the control function for multiple automated interacting production stations is a complex problem, even for skilled and experienced operators or process planners. When using mathematical optimisation techniques, it often becomes necessary to use simulation models to represent the problem because of the high complexity (i.e. simulation-based optimisation). Standard optimisation techniques are likely to either exceed the practical time frame or under-perform compared to the manual tuning by the operators or process planners. This paper presents the Constructive cooperative coevolutionary (C3) algorithm, which objective is to enable effective simulation-based optimisation for the control of automated interacting production stations within a practical time frame. C3 is inspired by an existing cooperative coevolutionary algorithm. Thereby, it embeds an algorithm that optimises subproblems separately. C3 also incorporates a novel constructive heuristic to find good initial solutions and thereby expedite the optimisation. In this work, two industrial optimisation problems, involving interaction production stations, with different sizes are used to evaluate C3. The results illustrate that with C3, it is possible to optimise these problems within a practical time frame and obtain a better solution compared to manual tuning.

  • 270.
    Glorieux, Emile
    et al.
    University West, Department of Engineering Science, Division of Automation Systems.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Automation Systems.
    Svensson, Bo
    University West, Department of Engineering Science, Division of Automation Systems.
    Lennartson, Bengt
    Chalmers University of Technology, Department of Signals and Systems.
    Optimisation of Interacting Production Stations using a Constructive Cooperative Coevolutionary Approach2014In: Proceedings of 2014 IEEE International Conference on Automation Science and Engineering (CASE), IEEE conference proceedings, 2014, p. 322-327Conference paper (Refereed)
    Abstract [en]

    Simulation-based optimisation carries the burden of computationally expensive fitness calculations. It is very often used to tackle large-scale optimisation problems with a relatively high level of complexity. Therefore, it is of interest to have optimisation techniques dedicated to simulation-based optimisation. This paper proposes a simulation-based optimisation approach, called Constructive Cooperative Coevolutionary (C3) search procedure, to optimise the control of interacting production stations. An optimisation algorithm is embedded in the C3 search procedure to optimise subproblems separately. It includes a novel constructive heuristic that creates a feasible solution for the considered problem efficiently. It also incorporates an extended version of the existing cooperative coevolutionary method that can handle large-scale optimisation problems. Furthermore, this paper presents a case study considering a sheet metal press line as an example of interacting production stations. In this case study, the performance of the proposedC3 search procedure is evaluated and compared with other optimisation algorithms. This shows that the C3 search procedure is able to successfully optimise the press line within a given number of fitness calculations, outperforming existing algorithms. Also, it is shown that C3 can be embedded with either stochastic or deterministic optimisation algorithms, without sacrificing performance.

  • 271.
    Glorieux, Emile
    et al.
    University West, Department of Engineering Science, Division of Production Systems.
    Franciosa, Pasquale
    University of Warwick, Warwick Manufacturing Group, CV4 7AL Coventry, UK.
    Ceglarek, Darek
    Warwick Manufacturing Group, University of Warwick, CV4 7AL Coventry, UK.
    End-effector design optimisation and multi-robot motion planning for handling compliant parts2018In: Structural and multidisciplinary optimization (Print), ISSN 1615-147X, E-ISSN 1615-1488, Vol. 57, no 3, p. 1377-1390Article in journal (Refereed)
    Abstract [en]

    The deformation of compliant parts during material handling is a critical issue that can significantly affect the productivity and the parts' dimensional quality. There are multiple relevant aspects to consider when designing end-effectors to handle compliant parts, e.g. motion planning, holding force, part deformations, collisions, etc. This paper focuses on multi-robot material handling systems where the end-effector designs influence the coordination of the robots to prevent that these collide in the shared workspace. A multi-disciplinary methodology for end-effector design optimisation and multi-robot motion planning for material handling of compliant parts is proposed. The novelty is the co-adaptive optimisation of the end-effectors' structure with the robot motion planning to obtain the highest productivity and to avoid excessive part deformations. Based on FEA, the dynamic deformations of the parts are modelled in order to consider these during the collision avoidance between the handled parts and obstacles. The proposed methodology is evaluated for a case study that considers the multi-robot material handling of sheet metal parts in a multi-stage tandem press line. The results show that a substantial improvement in productivity can be achieved (up to 1.9%). These also demonstrate the need and contribution of the proposed methodology.

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  • 272.
    Glorieux, Emile
    et al.
    University West, Department of Engineering Science, Division of Automation Systems.
    Svensson, Bo
    University West, Department of Engineering Science, Division of Automation Systems.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Automation Systems.
    Lennartson, Bengt
    University West, Department of Engineering Science, Division of Automation Systems. University West, Department of Engineering Science, Division of Production Systems. Department of Signals and systems, Chalmers University of Technology.
    Improved Constructive Cooperative Coevolutionary Differential Evolution for Large-Scale Optimisation2016In: Computational Intelligence, 2015 IEEE Symposium Series on, IEEE, 2016, p. 1703-1710, article id 7376815Conference paper (Refereed)
    Abstract [en]

    The Differential Evolution (DE) algorithm is widely used for real-world global optimisation problems in many different domains. To improve DE's performance on large-scale optimisation problems, it has been combined with the Cooperative Coevolution (CCDE) algorithm. CCDE adopts a divide-and-conquer strategy to optimise smaller subcomponents separately instead of tackling the large-scale problem at once. DE then evolves a separate subpopulation for each subcomponent but there is cooperation between the subpopulations to co-adapt the individuals of the subpopulations with each other. The Constructive Cooperative Coevolution (C3DE) algorithm, previously proposed by the authors, is an extended version of CCDE that has a better performance on large-scale problems, interestingly also on non-separable problems. This paper proposes a new version, called the Improved Constructive Cooperative Coevolutionary Differential Evolution (C3iDE), which removes several limitations with the previous version. A novel element of C3iDE is the advanced initialisation of the subpopulations. C3iDE initially optimises the subpopulations in a partially co-adaptive fashion. During the initial optimisation of a subpopulation, only a subset of the other subcomponents is considered for the co-adaptation. This subset increases stepwise until all subcomponents are considered. The experimental evaluation of C3iDE on 36 high-dimensional benchmark functions (up to 1000 dimensions) shows an improved solution quality on large-scale global optimisation problems compared to CCDE and DE. The greediness of the co-adaptation with C3iDE is also investigated in this paper.

  • 273.
    Glorieux, Emile
    et al.
    University West, Department of Engineering Science, Division of Production Systems.
    Svensson, Bo
    University West, Department of Engineering Science, Division of Production Systems.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Production Systems.
    Lennartson, Bengt
    University West, Department of Engineering Science, Division of Production Systems. Department of Signals and Systems, Chalmers University of Technology,Gothenburg, Sweden.
    Multi-objective constructive cooperative coevolutionary optimization of robotic press-line tending2017In: Engineering optimization (Print), ISSN 0305-215X, E-ISSN 1029-0273, Vol. 49, no 10, p. 1685-1703Article in journal (Refereed)
    Abstract [en]

    This article investigates multi-objective optimization of the robot trajectories and position-based operation-coordination of complex multi-robot systems, such as press lines, to improve the production rate and obtaining smooth motions to avoid excessive wear of the robots’ components. Different functions for handling the multiple objectives are evaluated on realworld press lines, including both scalarizing single-objective functions and Pareto-based multi-objective functions. Additionally, the Multi-Objective Constructive Cooperative Coevolutionary (moC3) algorithm is proposed, for Pareto-based optimization, which uses a novel constructive initialization of the subpopulations in a co-adaptive fashion. It was found that Paretobased optimization performs better than the scalarizing single-objective functions. Furthermore, moC3 gives substantially better results compared to manual online tuning, as currently used in the industry. Optimizing robot trajectories and operation-coordination of complex multi-robot systems using the proposed method with moC3 significantly improves productivity and reduces maintenance. This article hereby addresses the lack of systematic methods for effectively improving the productivity of press lines.

  • 274.
    Glorieux, Emile
    et al.
    University West, Department of Engineering Science, Division of Automation Systems.
    Svensson, Bo
    University West, Department of Engineering Science, Division of Automation Systems.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Lennartson, Bengt
    University West, Department of Engineering Science, Division of Manufacturing Processes. University West, Department of Engineering Science, Division of Production Systems. Chalmers.
    Optimised Control of Sheet Metal Press Lines2014In: Proceedings of the 6th International Swedish Production Symposium 2014 / [ed] Stahre, Johan, Johansson, Björn & Björkman, Mats, 2014, p. 1-9Conference paper (Refereed)
    Abstract [en]

    Determining the control parameters for sheet metal press lines is a large scale and complex optimisation problem. These control parameters determine velocities, time constants, and cam values of critical interactions between the equipment. The complexity of this problem is due to the nonlinearities and high dimensionality. Classical optimisation techniques often underperform in solving this kind of problems within a practical timeframe. Therefore, specialised techniques need to be developed for these problems. An existing approach is simulation-based optimisation, which is to use a simulation model to evaluate the trial solutions during the optimisation. In this paper, an efficient simulation-based optimisation algorithm for large scale and complex problems is proposed. The proposed algorithm extends the cooperative coevolutionary algorithm, which optimises subproblems separately. Hence, the optimisation problem must be decomposed into subproblems that can be evaluated separately. To optimise the subproblems, the proposed algorithm allows using embedded deterministic algorithms, next to stochastic genetic algorithms, getting the flexibility of using either type. It also includes a constructive heuristic that creates good initial feasible solutions to expedite the optimisation. The extension enables solving complex, computationally expensive problems efficiently. The proposed algorithm has been applied on an automated sheet metal press line from the automotive industry. The objective is to find control parameters that maximise the line’s production rate. The results show that the proposed algorithm manages to find optimal control parameters efficiently within the practical timeframe. This is a step forward in press line optimisation since to the authors’ knowledge this is the first time a press line has been optimised efficiently in this way.

  • 275.
    Goel, Sneha
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Hybrid powder-suspension plasma spraying for diverse function-dependent coating architectures2016Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Suspension Plasma Spraying (SPS) is an emerging plasma spray technique which overcomes the difficulties typically associated with feeding of fine powders (submicron or nano-sized) in conventional Atmospheric Plasma Spraying (APS) to develop interesting microstructural features for varied engineering applications, such as wear resistance, corrosion/oxidation protection, thermal barrier, etc. Another breakthrough in plasma spraying pertains to the advent of systems that allow axial injection of feedstock which considerably improves thermal exchange between the plasma plume and the injected feedstock, thereby enabling substantial enhancement in deposition rates/efficiency.

    The present study utilizes both the above advances in plasma spraying to demonstrate the ability to deposit various function-dependent coating architectures by sequential/simultaneous axial injection of both powder and a suspension feedstock, henceforth referred to as hybrid plasma spray. The results amply demonstrate the flexibility and versatility of the hybrid spray process for production of superior function dependent coating architectures. Sim-ultaneous injection of the two feedstocks to form composite coatings, which is the most challenging from a processing standpoint as it requires identification of a process window which is suitable for both powder and suspension, was investigated in particular detail using deposition of Al2O3-YSZ composites as a case study. Composite coating architectures produced by hybrid spraying showed good homogeneity and the microstructure of the coating was characterized by presence of multi-scale features attributable to co-deposition of powder (micron-sized Al2O3) and suspension (involving fine YSZ powder) feedstock.

    In order to better understand the role of particle size and the implications of a distributed second phase on the tribological behavior of coatings, properties of the above mentioned powder-suspension hybrid coatings were also comprehensively compared with (a) Al2O3 coatings deposited using powder (b) Al2O3 coatings deposited using suspension and (c) Al2O3-YSZ coatings deposited using both constituents as suspensions. It has been observed that fine particle size of the feedstock leads to improved tribological performance of the coating in comparison with micron-sized powder feed-stock. In addition, introduction of fine second phase into conventional coating using the hybrid approach has shown significant improvement in tribological response of the conventional coatings. However introduction of fine second phase in a fine structured coating matrix showed negligible effect on the tribological response of the coating.

  • 276.
    Gokavarapu, Naga Sai Pavan Rahul
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Termisk cyklisk utmattning studie av Gd2Zr2O7 / YSZ flerskikts termiska barriärbeläggningar2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    From many years YSZ is used as the top coat material for TBC's, as it has good phase stability up to 1200°C, higher fracture toughness, lower thermal conductivity, erosion resistance & higher coefficient of thermal expansion. But, it has a drawbacks at high temperature such as sintering and transformation of phases. For this reason new ceramic materials with pyrochlores crystal structure such as Gd2Zr2O7 are being considered as it has high melting points, phase stability, lower thermal conductivity and CMAS resistance. But it has low fracture toughness when compared to YSZ. In order to take advantage of low thermal conductivity and high thermal stability of gadolinium zirconate and avoiding the drawbacks of low coefficient of thermal expansion and low toughness using YSZ, a double/multi-layer coatings approach is being used. Therefore, multi-layer TBCs are sprayed and compared with single layer coating in this work. These coatings are processed by suspension plasma spraying. For single layer coating YSZ is used, for double layer coating YSZ as the intermediate coating and Gd2Zr2O7 as the top coat is used. Additionally, a triple layer coating system comprising YSZ, Gd2Zr2O7 and dense Gd2Zr2O7 as top coat is also sprayed. The as sprayed coatings are characterized for microstructure analysis using optical microscope and scanning electron microscope (SEM), elemental analysis of TGO using Energy-Dispersive Spectrometer (EDS). XRD analysis was done to identify various phases in the coating. Porosity analysis using Archimedes principle was carried out. Thermal cyclic fatigue (TCF) test of the sprayed coatings was carried out at 1100°C. Failure analysis of the TCF specimens was carried out using SEM/EDS. TCF results showed that the triple layer coatings (dense Gd2Zr2O7/Gd2Zr2O7/YSZ) had higher thermal cyclic fatigue life and lower TGO thickness when compared to single layer (YSZ) and double layer (Gd2Zr2O7/YSZ) TBCs.

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  • 277.
    Gran,, Ludvig
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Utveckling av parameter för svetsprocessen Nyckelhål-TIG i titan-6Al-4V för tjocklek 7 mm2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    GKN Aerospace Trollhättan produces components for the commercial, military aerospace and space industry. The company belongs to GKN PLC since 2012 which got approximately 58 000 employees and was founded over 250 years ago in Great Britain.

    Keyhole-TIG has gained attention in the aerospace industry for its capability of producing high quality welds in metals such as titanium and nickel-based alloys. The process has shown to complete welds in thickness up to 14 mm, which is a considerable difference in comparison to conventional TIG. Keyhole-TIG appears to be a more robust alternative to plasma arc welding because of fewer influencing factors.

    Today GKN Aerospace is welding a 7,3 mm thick titanium joint using plasma arc welding, but it fails occasionally which leads to quality deficiency costs. It is in the company's interest to investigate how Keyhole-TIG behaves so they can compare it to the existing welding method.

    The purpose of the study it to investigate how the key process parameters of Keyhole-TIG are affecting the welding geometries and to identify a welding parameter for material thickness 7 mm titanium that fulfill the company's requirement specification.

    A literature review was preformed to acquire knowledge about the process Keyhole TIG, control methods and statistical experimental design. A practical way of gathering information was made in the form of welding experiments, measurements and statistical analysis tool, which were made to investigate the parameter association and identify a potential parameter. The main parameters that were investigated were current, electrode distance and advancing speed. Limited areas occurred when creating the design of experiments because the constraints of current and advancing speed was affecting each other. Therefore, the design of experiments was created resembling a D-optimal design.

    The study’s conclusions were that the electrode distance should be short because it contributed to increased penetration, heat input was decreased and underfill was reduced. All key process variables impact on the welding geometries were identified except for underfill. Lastly a parameter was identified with a statistically optimizing tool that generated a valid weld geometry according to the requirements. The parameter was recommended to GKN Aerospace for future use. 

  • 278.
    Granlund, Erik
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Framtagning av koncept för tryckindikator och informationsöverföring för luftaxel2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The objective of the project has been to develop a concept for both indicating the pressure level in the rolling axle hoses and for transferring this information from the rotating shaft to non-rotating machine parts. The report's literature study describes sensor technology and information-transferring-techniques for non-stationary objects. Study visits and interviews have been made to pay attention to the demands and expectations of future stakeholders on the product. During the concept generation phase, several methods have been used, including function trees and investigations of patents. A total of 21 concepts were generated. During the concept screening and concept scoring phase, an independent engineering student has been used for feedback. A cost analysis based on estimates for the sub-concepts has been carried out before the concept selection. The work resulted in a total of four subconcepts. Two sub-concepts for pressure indication and two sub-concepts for information transfer. Prior to final conceptual selection, more assessment steps should be performed, for example, subcontractors should be contacted regarding quotation requests and a FMEA should be created.

  • 279.
    Gråsjö, Urban
    University West, School of Business, Economics and IT, Division of Law, Politics and Economics. University West, School of Business, Economics and IT, Divison of Law, Economics, Statistics and Politics.
    Accessibility to R&D and Patent Production2005Report (Other academic)
    Abstract [en]

    The main purpose in this paper is to study to what extent accessibility to R&D can explain patent production. Therefore a knowledge production function is estimated both on aggregated level and for different industrial sectors. The output of the knowledge production is the number patent applications in Swedish municipalities from 1994 to 1999. In order to account for the importance of proximity, the explanatory variables are expressed as accessibilities to university and company R&D. The total accessibility is then decomposed into local, intra-regional and inter-regional accessibility to R&D. As often is the case with R&D outputs, the regional distribution of patents is highly skewed with influential outliers. The estimations are therefore conducted with quantile regressions. The main results on aggregated level indicate that high accessibility (local) to company R&D has the greatest positive effects on patent production. The effects are statistically significant for municipalities with a patent production corresponding to the median and to quantiles above the median. Local accessibility to university R&D is only of importance for certain industrial sectors and not on aggregated level. There is also evidence that intra-regional accessibility to company R&D affects patent production positively. A conclusion is that concentrated R&D investments in companies situated in municipalities with a high patenting activity would not only gain the municipalities themselves, but also the patent production in other municipalities in the functional region.

  • 280.
    Grönberg, Christoffer
    University West, Department of Engineering Science.
    Simulering och cykeltidsberäkning av automatiserad produktionslina med hjälp av Process Simulate2010Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis has been carried out in collaboration with Löfqvist Engineering in Örebro. The task has been to perform a simulation of a large automation line, to be used in the manufacture of exhaust systems for trucks. Based on this simulation accurate cycle times for production are determined. These times can then be used by Löfqvist Engineering to verify the earlier estimated times.

    The work includes a literature review of Lean Production and how it works with automation. There is also some background information on Just In Time, different file formats and robot simulation in general for the reader to get a bit more background knowledge of the subject.

    The program that has been selected to perform the simulation is Tecnomatix Process Simulate and its built in Line Simulation module. The automation line consists of four handling robots, 13 operator stations and eight identical welding cells. Cycle times for the automation line have been determined and the result was 6 min 31s, for the automation line to complete one product. Cycle times were determined by calculating the average time to produce 10 pieces of products when the line was full of material.

    The report describes how the work for arriving at these cycle times have been performed and how simulation problems encountered during such operations have been resolved.

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  • 281.
    Gudfinnsson, Kriseins
    et al.
    University of Skövde, School of Informatics,Skövde, Sweden.
    Rose, Jeremy
    University of Skövde, School of Informatics,Skövde, Sweden.
    Aggestam, Lena
    University West, School of Business, Economics and IT.
    Tackling lack of motivation in aspirational analytics companies: SME examples from the manufacturing industry2019In: International Journal of Business Intelligence Research, ISSN 1947-3591, E-ISSN 1947-3605, Vol. 10, no 1, p. 1-18Article in journal (Refereed)
    Abstract [en]

    Establishing business intelligence analytics (BIA) in small- and medium-sized manufacturing enterprises is a pervasive problem. SME’s - the majority of businesses - play an important role in creating jobs, but research is primarily focused on large corporations. The authors worked with small manufacturing companies at the aspirational capability level but found that their motivation to introduce BIA was low. They had many business challenges but perceived the obstacles (primarily cost and effort) as too great, and their priorities were with operational issues. A two-phase approach based on a well-known analytics maturity model was devised to help raise company motivation. The article describes three studies in different companies using variations of the approach. Comparative analysis of the cases shows that demonstrating a clear path to improved functional efficiency is key to improving motivation, and that simple, easy to learn tools can provide these insights at little cost. Copyright © 2019, IGI Global.

  • 282.
    Guevara-Garca, Alfredo
    et al.
    McMaster University, Department of Chemistry and Chemical Biology.
    Echegaray, Eleonora
    Pontificia Universidad Catlica de Chile, Facultad de Qumica, Laboratorio de Qumica Terica Computacional (QTC).
    Toro-Labbe, Alejandro
    Pontificia Universidad Catlica de Chile, Facultad de Qumica, Laboratorio de Qumica Terica Computacional (QTC).
    Jenkins, Samantha
    University West, School of Business, Economics and IT, Division of Computer Science and Informatics.
    Kirk, Steven R.
    University West, School of Business, Economics and IT, Division of Computer Science and Informatics.
    Ayers, Paul W.
    McMaster University, Department of Chemistry and Chemical Biology.
    Pointing the way to the products Comparison of the stress tensor and the second-derivative tensor of the electron density2011In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 134, no 23, p. 234106-Article in journal (Refereed)
    Abstract [en]

    The eigenvectors of the electronic stress tensor can be used to identify where new bond paths form in a chemical reaction. In cases where the eigenvectors of the stress tensor are not available, the gradient-expansion- approximation suggests using the eigenvalues of the second derivative tensor of the electron density instead; this approximation can be made quantitatively accurate by scaling and shifting the second-derivative tensor, but it has a weaker physical basis and less predictive power for chemical reactivity than the stress tensor. These tools provide an extension of the quantum theory of atoms and molecules from the characterization of molecular electronic structure to the prediction of chemical reactivity. © 2011 American Institute of Physics.

  • 283.
    Gunnarsson, Håkan
    et al.
    University West, Department of Engineering Science.
    Johansson, Filip
    University West, Department of Engineering Science.
    Framtagning av koncept för monteringsstation2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor's thesis has been carried out at Parker Hannifin Manufacturing Sweden AB in Trollhättan. This report presents the work for producing and evaluating concepts for an assembly station. The company assembles three models of hydraulic pumps named F1, F2 and F3 in the assembly station. In the assembly station there is a screwing station that enables assembly of the pumps. The screwing station is badly adjusted for assembly of F3 and the assembly personnel may suffer from damage due to lack of ergonomics in the form of manual lifting.

    The purpose of this bachelor's thesis was therefore to improve ergonomics for the personnel and increase the flexibility in the screwing station. The goal was to produce a concept of an assembly station adapted for assembly of F1, F2 and F3 with transport of pumps to and from the screwing station where manual lifting does not exceed seven kilograms.

    By collecting information on the current assembly station, a zero-position description and a list of interpreted needs and requirements were complied. The list included the needs and requirements of the assembly personnel, to achieve a working assembly station and from the organization. Based on collected information and identified improvement areas, solutions were generated and combined into concepts. Generated concepts included solutions for reducing ergonomic risk and the possibility to standardize the tools in the screwing station. The concepts were screened in a screening matrix where the concepts were evaluated against the current assembly station. The remaining concepts were graded in a selection matrix where a winning concept was selected. To identify and resolve any problem that may arise when the concept is realized, the concept was further evaluated by modelling and simulating in a computer program. 

    The result of the concept development process and the concept recommended to Parker was named “H+”. Concept H+ consists of a conveyor with an integrated screwing station and a lifting device between the conveyor and the next part of the assembly line. The screwing station has a rotating shaft where F1, F2 and F3 are fixed with a standardized tool. The rotating shaft allows torqueing of screws from the front of the screwing station. Assembly of F3 has been adapted in the concept through standardized tools. The concept also reduces ergonomic risks, as transport from the screwing station is made by a conveyor and a lifting device. Manual lifting over seven kilograms has thus been eliminated. If Parker chooses to develop and realize the concept they will, according to this report, be provided with an assembly station with increased flexibility and improved ergonomics for their employees.

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  • 284.
    Gupta, Mohit Kumar
    et al.
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Dwivedi, Gopal
    Stony Brook University, USA.
    Nylén, Per
    University West, Department of Engineering Science, Research Environment Production Technology West.
    Vackel, Andrew
    Stony Brook University, USA.
    Sampath, Sanjay
    University West, Department of Engineering Science, Research Enviroment Production Technology West.
    An Experimental Study of Microstructure: Property Relationships in Thermal Barrier Coatings2013In: Journal of thermal spray technology (Print), ISSN 1059-9630, E-ISSN 1544-1016, Vol. 22, no 5, p. 659-670Article in journal (Refereed)
    Abstract [en]

    The thermal-mechanical properties of thermal barrier coatings are highly influenced by the defects present in coating microstructure. The aim of this study was to meet the future needs of the gas turbine industry by further development of zirconia coatings through the assessment of microstructure-property relationships. A design of experiments was conducted for this purpose with current, spray distance, and powder feed rate as the varied parameters. Microstructure was assessed with SEM and image analysis was used to characterize porosity content. Evaluations were carried out using laser flash technique to measure thermal properties. A bi-layer beam curvature technique in conjunction with controlled thermal cycling was used to assess the mechanical properties, in particular their nonlinear elastic response. Coating lifetime was evaluated by thermo-cyclic fatigue testing. Relationships between microstructure and coating properties are discussed. Dense vertically cracked microstructure and highly porous microstructure with large globular pores were also fabricated. Correlations between parameters obtained from nonlinear measurements and lifetime based on a priori established microstructural analysis were attempted in an effort to develop and identify a simplified strategy to assess coating durability following sustained long-term exposure to high temperature thermal cycling.

  • 285.
    Gupta, Mohit Kumar
    et al.
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Nylén, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    A modelling approach to design of microstructures in thermal barrier coatings2013In: Journal of Ceramic Science and Technology, ISSN 2190-9385, Vol. 4, no 2, p. 85-92Article in journal (Refereed)
    Abstract [en]

    Thermo-mechanical properties of TBCs are strongly influenced by coating defects, such as delaminations and pores, thus making it essential to have a fundamental understanding of microstructure-property relationships in TBCs to produce a desired coating. Object-Oriented Finite element analysis (OOF) has been shown previously as an effective tool for evaluating thermal and mechanical material behaviour, as this method is capable of incorporating the inherent material microstructure as an input to the model. In this work, OOF was used to predict the thermal conductivity and effective Young's modulus of TBC topcoats. A Design of Experiments (DoE) was conducted by varying selected spray parameters for spraying Yttria Stabilized Zirconia (YSZ) topcoat. Microstructure was assessed with SEM and image analysis was used to characterize porosity content. The relationships between microstructural features and properties predicted by modelling are discussed. The microstructural features having the most beneficial effect on properties were sprayed with another spray gun so as to verify the results obtained from modelling. Characterisation of the coatings included microstructure evaluation, thermal conductivity and lifetime measurements. The modelling approach in combination with experiments undertaken in this study was shown to be an effective way in achieving coatings with optimised thermo-mechanical properties.

  • 286.
    Gupta, Mohit Kumar
    et al.
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Nylén, Per
    University West, Department of Engineering Science, Research Enviroment Production Technology West.
    Design of Low Thermal Conductivity Thermal Barrier Coatings by Finite Element Modelling2011In: Surface Modification Technologies XXIV: SMT24, Dresden, September 7-9, 2010 / [ed] T. S. Sudarshan, Eckhard Beyer, and Lutz-Michael Berger, 2011, p. 353-365Conference paper (Refereed)
    Abstract [en]

    Fundamental understanding of relationships between coating microstructure and thermal conductivity is important to be able to understand the influence of coating defects, such as delaminations and pores, on heat insulation in thermal barrier coatings (TBC). Object Oriented Finite element analysis (OOF) has recently been shown as an effective tool for evaluating thermo-mechanical material behaviour as this method is capable of incorporating the inherent material microstructure as an input to the model. The objective of this work was to evaluate a procedure where this technique is combined with Tbctool, a plasma-sprayed TBC like morphology generator, thus enabling development of low thermal conductivity coatings by simulation. Input parameters for Tbctool were computed from SEM images of sprayed microstructures using the image analysis software, Aphelion. Microstructures for as-sprayed as well as heat treated samples were evaluated. The thermal conductivities of the artificially generated microstructures were determined using OOF. Verification of the modelling procedure was performed by comparing predicted values by OOF with corresponding measured values using the laser flash technique. The results, although tentative in nature, indicate that the proposed simulation approach can be a powerful tool in the development of new low conductivity coatings.

  • 287.
    Gupta, Mohit Kumar
    et al.
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Nylén, Per
    University West, Department of Engineering Science, Research Enviroment Production Technology West.
    Structure-property Relationships in Thermal Barrier Coatings by Finite Element Modelling2012In: Surface Modification Technologies XXV : proceedings of the Twenty Fifth International Conference on Surface Modification Technologies: SMT25, Trollhättan, June 20-22, 2011 / [ed] T. S. Sudarshan, and P. Nylén, [Chennai]: Valardocs , 2012, p. 175-184Conference paper (Refereed)
    Abstract [en]

    The thermal and mechanical properties of Thermal Barrier Coating systems (TBCs) are strongly influenced by coating defects, such as delaminations and pores, thus making it essential to have a fundamental understanding of microstructure-property relationships in TBCs, to produce a desired coating. Object-Oriented Finite element analysis (OOF) has been shown previously as an effective tool for evaluating thermal and mechanical material behaviour, as this method is capable of incorporating the inherent material microstructure as an input to the model. In this work, OOF was used to predict the thermal conductivity and effective Young’s modulus of TBC topcoats. A Design of Experiments (DoE) was conducted by varying selected spray parameters for spraying Yttria Partially Stabilized Zirconia (YPSZ) topcoat. Characterisation of the coatings included microstructure, porosity and crack content and thermal conductivity measurements. The relationships between microstructural features, thermal conductivity and Young’s modulus are discussed.

  • 288.
    Gupta, Mohit Kumar
    et al.
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Weber, André
    Karlsruhe Institute of Technology, Germany.
    Markocsan, Nicolaie
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Gindrat, Malko
    Oerlikon Metco, Switzerland.
    Electrochemical Performance of Plasma Sprayed Metal Supported Planar Solid Oxide Fuel Cells2016In: Journal of the Electrochemical Society, ISSN 0013-4651, E-ISSN 1945-7111, Vol. 163, no 9, p. F1059-F1065Article in journal (Refereed)
    Abstract [en]

    High production cost is one of the major barriers to widespread commercialization of solid oxide fuel cells (SOFCs). Thermal spraytechniques are a low cost alternative for the production of SOFCs. The objective of this work was to evaluate the electrochemicalperformance of cells produced by plasma spraying. The anode was deposited on a porous metallic support by atmospheric plasmaspraying (APS) whereas the electrolyte was deposited by plasma spray-thin film (PS-TF) technique, which can produce thin anddense coatings at high deposition rates. The cathode was deposited by screen-printing and in-operando sintering. The electrochemicaltests were performed at 650–800◦C. Current-voltage characteristics and impedance spectra were measured and analyzed. The impactof electrolyte composition and layer thickness on the gas tightness of the electrolyte and the area specific resistance of the cell isdiscussed. The results show that the applied thermal spraying techniques are a potential alternative for producing SOFCs.

  • 289.
    Gupta, Mohit Kumar
    et al.
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Weber, André
    Karlsruhe Institute of Technology, Germany.
    Markocsan, Nicolaie
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Helden, Nadine
    Oerlikon Metco, Germany.
    Development of plasma sprayed Ni/YSZ anodes for metal supported solidoxide fuel cells2017In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 318, p. 178-189Article in journal (Refereed)
    Abstract [en]

    Solid oxide fuel cells (SOFCs) offer a promising technique for producing electricity by clean energy conversionthrough an electrochemical reaction of fuel and air. Plasma spraying could be a potential manufacturing routefor commercial SOFCs, as it provides a distinct advantage especially in case of metal supported cells (MSCs) byallowing rapid processing at relatively low processing temperatures preventing thus the degradation of themetallicsubstrate. The objective of this work was to develop nickel/yttria stabilised zirconia (Ni/YSZ) anodes withhigh porosity and homogeneous phase distribution by atmospheric plasma spraying forMSCs. Various feedstockmaterial approaches were explored in this study, both with single injection aswell as separate injection of differentfeedstock materials , and with and without the use of pore formers to create additional porosity. The advantagesand issues with each material route were investigated and discussed. It was shown that agglomerated Ni/YSZ/polyester feedstock material resulted in the best distribution of Ni and YSZ in the anodemicrostructurewithhomogeneous porosity. Subsequently, the Ni/YSZ/polyester material route with different amounts and size distributionsof polyester was chosen to develop anode symmetrical cells using a commercial zirconia sheet as supportfor electrochemical testing. The Ni/YSZ/polyester anode powder with 10 wt.% standard size polyesterexhibited the best electrochemical performance. The results show that plasma spraying of the agglomeratedNi/YSZ/polyester could be a promising route to achieve high performance and rapid production anodes withoutusing the carcinogenic nickel oxide.

  • 290.
    Gustafsson, Andreas
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Modalanalys av ett lågtrycksturbinhus till en jetmotor2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    As flight travel has increased dramatically over the past 30 years and the fact that flight travel consumes a lot of energy in form of jet fuel has led to an intensified search for lighter and more fuel-efficient designs. Thereof, the aircraft engine area is strongly affected. This yields more thin-walled structures, which means that they show an increased tendency to vibrate, especially during manufacturing.

    In the area of chatter vibrations, there is a large extent of literature and research that describe and prevent vibrations during machining. One approach is to predict instability and chatter vibrations. The approach of predict instability have been implemented in this project, in order to generate optimal cutting parameters in the manufacturing of a low pressure turbine casing.

    A modal analysis has been performed on the machining system that is included in the manufacturing of the low pressure turbine casing. Here, modal analysis on each part of the machining system has generated modal parameters that indicate the structures dynamic stiffness.

    Based on the modal analysis and the specific cutting force for Inconel 718, the actual work material, stability lobe diagrams has been generated out of which the axial depth of cut and spindle speed that yields chatter free machining could be selected.

    In parallel with the modal analysis, a FEM-analysis made as a modal analysis has been performed in ANSYS Workbench. This has been executed to improve the machining system and the supports that are included in the tooling fixture to raise the stability frontier for this particular system.

    The results from this project show that it is not possible to achieve significantly increased depths of cut or spindle speeds in the machining of the low pressure turbine casing. However, Cutpro still shows the potential that exists in this software, which GKN Aerospace can benefit from, out of a quality perspective where GKN Aerospace has the chance to increase the control of their manufacturing processes.

  • 291.
    Gustafsson, Fredric
    et al.
    University West, Department of Engineering Science.
    Ulldal, Jonatan
    University West, Department of Engineering Science.
    Optimering av smidesgeometri för P-fläns på bakre turbinstativ (TEC)2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis work has been performed at Volvo Aero Corporation in Trollhättan, at the department of “hot structures” involving aircraft engine GP7000. The purpose with the study was to investigate the possibility to reduce size of the forging of flanges on the rear turbine frame when purchasing. Thereto examine the parameters that affect the flanges motion during the manufacturing process. The goal was to provide Volvo Aero with foundation to later bring in slimmed forgings. In order to supply the company with a concrete result the report was limited into studying the P-flange.

    During the manufacturing process the flanges moves. By measuring the deviation from calculated points on nominal geometry relative to scanned geometry after affecting operations, the motion could be mapped. From these studies two proposals for optimization was presented.

    The first proposal is based on evening out the tilt caused from the TIG-welding operation. Purchasing tilted forgings would compensate the angle and make room for further savings. If the introduction became a success it could eventually mean that a whole operation (roughing) might be removed. Due to insufficient knowledge about whether the tilt would change as expected after introduction, it requires another analyze after implemented before material can be reduced.

    The second proposal is based on reducing material solely on the point´s motion. Calculating with four sigma safety (99,379%) on the movements gave information about how much excess material that could be reduced on the forgings. Considerations about whether decreased material would modify the movement pattern have been taken into account. The result shows that 10 % from the bought in forgings can be removed directly.

    The authors suggest that Volvo Aero begin with the tilt-proposal as a first step in bringing in slimmed forgings. For future work the company could implement the approach taken on this report to the other flanges.

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  • 292.
    Gustafsson, Oliwer
    et al.
    University West, Department of Engineering Science.
    Selvö, Lucas
    University West, Department of Engineering Science.
    High Thermal Inertia Solar Cavity Receiver Development: THICAV2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A project led by Tewer Engineering called High Thermal Inertia Solar Cavity Receiver (THICAV) has been initiated with the goal to refine their previous solar receiver and make it possible to retrofit to already existing industries. This cavity receiver is practically designed to directly heat different industries with the transfer fluid and not be converted to electricity. Therefore, it could replace natural gas and other non-renewable energy sources. This causes high demands on good adaptability and cost-effective solutions. Besides the design, important topics are related to material choice and type of manufacturing process. This thesis will analyze the suitability of manufacturing through Wire Arc Additive Manufacturing (WAAM) and which materials are adequate for the receiver.

    Literature studies laid the foundation for this thesis which contributed to both material selection and determination of the initial welding parameters. A design of experiment was conducted to investigate the outcome of different welding parameters for the selected materials. The outcome of the different welding parameters was validated and verified through mechanical testing. Finally, a scaled down prototype of the most complex parts of the receiver was manufactured with the most suitable welding parameters.

    With the given conditions, AISI 309 and Inconel 625 were chosen from the material selection and further investigated. However, there are other alloys in the same material groups which might expose a higher performance e.g., better thermal properties. The selected materials were considered most suitable due to previous knowledge related to WAAM of these alloys and material availability.

    The material evaluation exposes that heat input has a very limited impact on the mechanical properties for both materials and it is difficult based on the acquired results to determine which welding parameters that are best. In terms of producibility higher interpass temperatures are beneficial as it speeds up production. Therefore, it can be determined that an interpass temperature of 200°C and 1000 mm/min torch travel speed are the most adequate parameters for the WAAM process for these two materials.

    The aim of prototype manufacturing was to determine if the receiver was printable with the chosen material and the WAAM method. Even if the prototype was printed only in AISI 309 a similar behavior could be observed for welding of Inconel 625. It could therefore be established that receiver most likely is printable with both materials since the prototype contained the most complex parts of the receiver.

  • 293.
    Gustafsson, Pontus
    et al.
    University West, Department of Engineering Science, Divison of Natural Sciences, Surveying and Mechanical Engineering.
    Larsson, Patrik
    University West, Department of Engineering Science, Divison of Natural Sciences, Surveying and Mechanical Engineering.
    Utkastbegränsning samt anpassning av krockgardiner vid sidorutor i bagageutrymme2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor’s thesis was performed as a concept development project at Autoliv Sverige AB, an automotive safety company located in Vårgårda, Sweden.

    US vehicle safety standards require countermeasures to prevent a vehicle occupant from ejection through side windows during a rollover crash. Autoliv is currently using a three-row inflatable curtain to fulfil these requirements but wish to evaluate possibilities for a different type of countermeasure for side windows in a vehicle’s cargo area. Main evaluation parameters were cost, weight, size, and ejection mitigation performance.

    To reach the purpose of the project, concept generation, evaluation and simulation has been performed prior to building a prototype. The prototype was built to test a function principle and not to be considered as a final concept. It was tested in a horizontal impactor to provide further evaluation data.

    By generating concepts, conducting simulations, construct a prototype and perform an impact test, an evaluation and comparison between new and old concepts can be performed. The impactor tests indicated that the identified function principle can provide performance necessary to prevent ejection.

    Conclusions was made that even if the physical prototype did not surpass the limits regarding cost, weight or size, the function has great opportunities for refinement, unless any existing patents would hinder further development. It performs best and show great potential in small windows and gives a minor increase in ejection mitigation performance in larger windows. Weight saving can be achieved if a refined prototype can be implemented

  • 294.
    Gustafsson, Rickard
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Lunde, Petronella
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Möjligheter i restmaterialet från stickindustrin: En konceptstudie2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Consumption of textiles, in the form of clothing and footwear, has increased by 40% in Sweden between 1999 and 2009. It is, in Sweden, annually bought 15 kg of textiles per person and picking-analyses shows that around 8 kg textiles are thrown away as sack-waste and domestic refuse. The increased consumption has led to increased negative environmental impact, as a large proportion of the products from the textile industry finally ends up in incineration facilities and landfill. Increased consumption has also resulted in increased production, which also increase the textile industry's negative environmental impact. Part of the increased environmental impacts can be directly traced to the combustion of waste materials from the production.

    This thesis treats the waste material from the Swedish garment manufacturer Ivanhoe AB and their cutting process in the form of pattern-trimming in felted wool fabric. Pattern-trimming is a process where the parts, which will be stitched into a garments, are cut out from one piece of fabric. The process generates waste material which the company don't take advantage of today.The objective of this project was to, through the identification of possible recycling methods for the waste material, produce concepts which will be feasible to the company. The product development process used in the project is based on a tiered approach described in Ulrich and Eppinger's book Product Development: construction and design. The project's product development process included the following steps; planning, identification of customer requirements, information gathering, concept generation and selection of concepts.

    The project resulted in three possible strategies that can be used for making the waste material useful. The strategies identified is Recycling, Patchwork Design and New Products. The latter two strategies was chosen to continue working with and develop concepts. The project finally resulted in six concepts, three concepts to each of the two chosen strategies. Before the company starts the production of one or more of the concepts, further evaluation should be carried out to ensure both economic and environmental sustainability.

  • 295.
    Gustafssson, Filip
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Mattsson, Idha
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Materialflödesoptimering: Siemens2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Siemens Industrial Turboamachinery AB stands before an expansion of the company caused by increased volumes of production and new articles to produce, which results in lack of space. The high demands on production contributes with large orders of details from the production to the logistics department, which cannot handle the variations.

    The purpose with this project is to get a better supply flow in the business whom supports the planning which is made for the production. This project also aims at creating a better understanding among the employees, how the supply chain affects the organization and an optimization of the milkround to decrease the variation of delivery time. The goals during this work is to determine and stabilize the demands and the delivery processes, visualize the need of transportation and secure the time of delivery. This study is partly qualitative and partly quantitative, with a base on interviews and collecting of data by measurements. The information/data is then used in the problem solving method of Six Sigma. Six Sigma is a systematic problem solving method which uses statistical quality tools. In this work a pres-tudy is included which also is performed at the company. The pre study contain the two first phases of the DMAIC method, define and measure.

    The result of the phases in the pre-study, define and measure, was that the group gained a greater understanding of the problem by identifying the stakeholders and costumers with their demands. After performing interviews with all the team leaders, the group realized that they had problem with the planning and many of them thought that the cause was because of the sudden appearance of material from other production groups. The measuring per-formed on the (by the group) identified problems showed the magnitude of the problem. This resulted in a cost–benefit analysis which shows the value of performing this project. The analysis phase consisted of analyzing the measurements that had been done and resulted in a focus area contained how the orders should be done and what the milkround frequency should be. During the improve phase a number if improvements was produced; priority lists, guides and a suggestion of a development of the business system.

    The conclusions from this project is that the company should start with simple solutions and create a well-structured flow and a standardized work which all employees follows. There is a lot of possible developments in the company but to reach world class the simple problems should be solved first. The future work laying a head of Siemens is among others to imple-ment the suggestions from the group of a system development to support the logistics in form of computers for the forklifts and ordering through SAP at decided times.

  • 296.
    Gustavsson, Alexander
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Zachariasson, Linus
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Utveckling av länkage till skogsmaskin2021Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this bachelor’s thesis was to develop and present a solution to mount a flail head on Alstor 840. There is currently no existing solution to mount a flail head on Alstor 840 and Alstor haven’t develop one either. The mounting solution shall be easy to install and have a robust construction. The flail head’s angle needs to be adjustable with the help of a hydraulic cylinder. A flail head has been chosen, and the presented solution is developedexclusively for that flail head. The project has followed a structured product development process where multiple methodshave been used. QFD, Brainstorming, Concept screening and Concept scoring are examples of methods used to generate and choosing concepts. The chosen concept has then gone through both preliminary and detail-design stages to generate 3D models in CAD, FEM-calculations and 2D drawings.The final solution consists of two parts called hydraulic attachment and linkage. The linkage will connect the flail head and the crane on Alstor 840. The hydraulic attachment mounts on the tip of the crane. A hydraulic cylinder is then mounted between the hydraulic attachment and the linkage. This concept fulfills customer needs for being robust, easy to mount, easily maneuvered, adjustable and it doesn’t occupy space on the crane. Drawing of constructed parts have been produced and is shown in the thesis.

  • 297.
    Gustavsson Christiernin, Linn
    et al.
    University West, Department of Engineering Science, Division of Production Systems.
    Augustsson, Svante
    University West, Department of Engineering Science, Division of Production Systems.
    Interacting with Industrial Robots: A Motion-based Interface2016In: AVI '16 Proceedings of the International Working Conference on Advanced Visual Interfaces / [ed] Paolo Buono, Rosa Lanzilotti, Maristella Matera, New York: ACM Digital Library, 2016, p. 310-311Conference paper (Refereed)
    Abstract [en]

    Collaborative industrial robot cells are becoming more and more interesting for industry through the new Industrie 4.0 initiative. In this paper we report early work on motion-based interaction with industrial robots. Human motion is tracked by a Kinect camera and translated into robot code. A group of tests subjects are asked to interact with the system and their activities are observed. Lessons learned on interaction challenges in a robot cell are reported.

  • 298.
    Gustavsson, Daniel
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Maintenance and its impact on overall equipment efficiency2021Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A Pig System is the practice of cleaning up moving liquid in a pipe using a plug called Pipe Inspection Gauge (PIG). This leaves no residual product in the pipe and secures against cross-contamination.

    Nouryon site Stenungsund has the largest Pig System in Sweden. This system is divided into groups and Group 15 has breakdowns that lead to costly production stops. These stops can entail work from manually disassembling sections of the group to insert clearance pigs to blow out broken pieces of other pigs. It can also mean manual steaming where hardened raw material has collected. The reason all of this leads to production stops is that the area where maintenance is performed is considered dangerous during production and thus all reactors must stop during maintenance causing a lower OEE number.

    The purpose is to find the root causes for corrective maintenance and to create a list of suggested improvements to mitigate production stops and thus optimising the production lines at the facility on-site.

    During the work, the system is defined with schematics, components listed from archives, common problems listed from operators experience and this correlated to work orders that are provided by the internal documentation system at Nouryon on site.

    The work orders are sorted by corrective maintenance and categorised from the text provided by the staff on the order. The categorisation of these work orders is where validity becomes a large factor in the study. The reason is that the text provided in these orders are written by individuals with different levels of detail and thus is an estimate of what the reason for the maintenance orders is. These orders are compiled and compared to what the reason for production stops are and prioritised.

    The result of the study end with a list of improvements that covers all the different issues discovered. The problems and corresponding solutions are prioritised with an FMEA that is confirmed by stakeholders on site.

    Further studies concerning lifetime calculation, alternative pigs and new sensors are suggested as all these reasons requires further investigation and testing to get a real answer concerning the pig system. 

  • 299.
    Gustavsson, Linn
    et al.
    University West, School of Business, Economics and IT, Division of Urban Planing and Development.
    Augustsson, Svante
    University West, Department of Engineering Science, Division of Production Systems.
    Vallo Hult, Helena
    University West, School of Business, Economics and IT, Divison of Informatics. NU Hospital Group (SWE).
    Trigger Points Of Fear And Distrust In Human-Robot Interaction: The Case Of Cooperative Manufacturing2022In: IRIS 2022, the 45th Information Systems Research Seminar in Scandinavia: Proceedings, Association for Information Systems, 2022, p. 18-31, article id 3Conference paper (Refereed)
    Abstract [en]

    Digital technology is becoming ubiquitous and embedded as an integrated part of our daily lives, in which the digital and the physical worlds are increasingly interconnected and intertwined. While advanced technology can provide tremendous benefits and opportunities, it can also be very complex and challenging to understand, potentially leading to fear, suspicion, and distrust. This paper investigates a case of human-robot interaction in cooperative manufacturing, focusing on understanding how operators, managers and viewers feel about cooperating with industrial robots using potentially dangerous tools like nail guns. The aim of the study is to identify how human reactions to technology-induced change can be understood. The research question is: how can different trigger points of fear or distrust in technology be understood in the context of human-robot interaction? The findings reveal three key factors in overcoming fear, creating trust and encouraging interaction: knowledge, control, and self-preservation. The main contribution is illustrated through suggested guidelines for aspects that have to be practically considered when building this type of flexible robot cell for interacting with industrial robots in a real setting.

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  • 300.
    Göransson, Daniel
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Haaga, Jerry
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Framtagning av en mobilhållare för bilar2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The objective of this thesis has been to develop and design a mobile phone holder for cars. A mobile phone holder can fulfil many purposes, and with the legislation today stating that communication equipment should not interfere when driving a vehicle, this type of product becomes extra important. The holder has been developed to enable simple use through acombination of user friendly functions. A few examples of functions are; easy mounting and demounting of mobile phone, automatic connection to car and wireless charging. Through a structured product development process, where tested methods have been used to identify requirements, generate concepts and choosing concept, an amount of concepts have been created and finally narrowed down to one final winner. Examples of methods and tools that has been used is interviews and House of Quality for identifying requirements, TRIZ Effects Database and Merlin for generating concepts and finally Concept screening and Concept scoring for the selection. The chosen concept has thereafter gone through necessary construction work for creating CAD-models, performing FE-analysis and 3D-printing a prototype. The final concept meets the requirement of easy use through simple one-hand mounting and demounting of mobile phone. The solution also works with a wide variety of mobilephones without the need to make adjustments. The concept is designed and prepared for integrating techniques such as NFC and Qi-charging in future work. More work needs to be done regarding the constructions strength, choice of material and fulfilling of laws before proceeding any further.

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