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  • 301.
    Runnemalm, Anna
    et al.
    University West, Department of Engineering Science, Division of Automation Systems.
    Broberg, Patrik
    University West, Department of Engineering Science, Division of Automation Systems.
    Henrikson, Per
    GKN Aerospace Engine System, Trollhättan.
    Ultraviolet excitation for thermography inspection of surface cracks in welded joints2014In: Nondestructive Testing and Evaluation, ISSN 1058-9759, E-ISSN 1477-2671, Vol. 29, no 4, p. 332-344Article in journal (Refereed)
    Abstract [en]

    Infrared thermography is a non-contact and full field inspection method which has proven to be suitable for automatic surface crack detection. For automatic analysis of the inspection results, a high signal-to-noise ratio (SNR) is required. In this paper an alternative excitation method, using ultraviolet (UV) illumination, is presented and evaluated. Artificial surface defects, so-called notches, in a titanium plate are detected both in the weld seam and in the heat affected zone. Notches with a size from 80 mm in width and 250 mm in length are detected. The SNR using UV illumination is compared with that using flash lamp excitation. The results show that UV illumination using a mercury lamp is a good alternative as excitation source for thermography when detecting surface cracks. To validate the excitation method, results from real surface cracks are included.

  • 302.
    Runnemalm, Anna
    et al.
    University West, Department of Engineering Science, Division of Automation Systems.
    Liu, Tongwein
    Ericsson, Mikael
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Appelgren, Anders
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Influence of Vibration Induced Disturbances in an Automatic Inspection Cell2013In: Robotics in Smart Manufacturing / [ed] Pedro Neto,António Paulo Moreira, 2013, p. 191-202Conference paper (Refereed)
    Abstract [en]

    In the modern manufacturing industry, quality assurance is important. Over the last few years, the interest in automatic inspection has increased and automatic non-destructive testing (NDT) has been introduced. A general automated inspection cell consists of a mechanized system for scanning and a computer system for automatic analysis of the data. In the manufacturing industry, it is preferable to use industrial robots as the scanning equipment since they offer great flexibility, excellent support organization and the in-house know-how is normally high. Another benefit is that a robot can carry different inspection equipment and an inspection cell can therefore include more than one NDT method. For an automatic analysis, high quality of the resulting data is essential. However, a non-stable condition of the NDT sensor mounted on the robotic arm may influence the results. This paper focuses on the influence of the vibration induced disturbances on the results from an NDT system. Vibration amplitude of a point to point robot movement on the robotic arm is measured. The influence of vibration disturbances on the inspection results are evaluated on the thermal images from a thermography system mounted on a six axis industrial robot. The thermal images taken by the system during the movement and after the stop of the robot are evaluated, and the influence of the vibration in these two situations is considered.

  • 303.
    Rydholm, Jonas
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Implementering av underhållssystem vid en tillverkande industri.2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The company in the study was experiencing a problem when it comes to dealing with maintenance-work. The processes for bug tracking and ordering of spare parts is time con-suming and involves work from several different people. Most of all maintenance work performed is unplanned and a functioning follow-up work is missing.

    The purpose of the thesis was to help improving the company's efficiency by optimizing the maintenance work. This was achieved by a proposal for a maintenance system and vari-ous approaches to improve the maintenance work.

    During the project a maintenance log book was been designed in Excel. The log book is used to log all maintenance activities that occur in the production. These logs are the basis for most of the calculations carried out during the project.

    The calculations aimed to identify where in the process most errors occur and what the na-ture of those errors are. To demonstrate the potential of a maintenance system the profit opportunities that can be achieved through the implementation of a maintenance system and new working methods were calculated.

    The study resulted in a proposal for a maintenance system that suited the company's needs, situation and problems. In addition to the introduction of a maintenance system, it was also clear that the company needs to reduce the amount of unplanned downtime. To achieve this it is important to involve the operators with maintenance work and they shall perform all the works of the simpler kind. The maintenance department can then, thanks to the re-leased time, focus on finding the root causes of problems and perform scheduled mainte-nance to reduce the amount of unplanned maintenance.

    Improving the maintenance work and introduce Total Productive Maintenance (TPM) is a time consuming process that might go on for years. In order to facilitate the work and re-duce the risk of falling back into old habits an implementation model was designed for the TPM-work. The model is intended as a future work for the company to facilitate the work of reaching even higher efficiency.

  • 304.
    Sadeghimeresht, Esmaeil
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Corrosion Behavior of HVAF-Sprayed Bi-Layer Coatings2016Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    In a variety of engineering applications, components are subjected to corrosive environment. Protective coatings are essential to improve the functional performances and/or extend the lifetime of the components. Thermal sprayingas a cost-effective coating deposition technique offers high flexibility in coatings' chemistry/morphology/microstructure design. However, the inherent pores formed during spraying limit the use of coatings for corrosion protection. The recently developed supersonic spray method, High-Velocity-Air-Fuel (HVAF), brings significant advantages in terms of cost and coating properties. Although severely reduced, the pores are not completely eliminated even with the HVAF process. In view of the above gap to have a high quality coating, bi-layer coatings have been developed to improve the corrosion resistance of the coatings. In a bi-layer coating, an intermediate layer is deposited on the substrate before spraying the coating. The electrochemical behavior of each layer is important to ensure a good corrosion protection. The corrosion behavior of the layers strongly depends on coating composition and microstructure, which are affected by feedstock material and spraying process. Therefore, the objective of the researchis to explore the relationships between feedstock material, spraying process, microstructure and corrosion behavior of bi-layer coatings. A specific motivationis to understand the corrosion mechanisms of the intermediate layer which forms the basis for developing superior protective coatings. Cr3C2-NiCr top layer and intermediate layers (Fe-, Co- and Ni-based) were sprayed by different thermal spraying processes. Microstructure analysis, as well as various corrosion tests, e.g., electrochemical, salt spray and immersion tests were performed. The results showed a direct link between the corrosion potential (Ecorr) of the intermediate layer and the corrosion mechanisms. It was found that the higher corrosion resistance of Ni-based coatings than Fe- and Co-based coatings was due to higher Ecorr of the coating in the galvanic couple with top layers. Inter-lamellar boundaries and interconnected pores reduced the corrosion resistance of intermediate layers, however a sufficient reservoir of protective scale-forming elements (such as Cr or Al) improved the corrosion behavior.

  • 305.
    Sadeghimeresht, Esmaeil
    et al.
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Markocsan, Nicolaie
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Nylén, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    HVAF thermal spray Fe-based coating: An environmentally acceptable alternative to cobalt-based coating2015Conference paper (Refereed)
    Abstract [en]

    Fe-based coatings were widely used in the corrosive environment of various indus-tries. It was replacing expensive cobalt-based alloys, which face a ban in the future due to serious health and environmental risks. The aim of the present work was to compare low temperature corrosion behavior of some Fe- and Co-based coatings produced by High-Velocity Air Fuel (HVAF) thermal spraying. Polarization and elec-trochemical impedance spectroscopy (EIS) tests were carried out in 3.5 wt.% NaCl solution at 25°C. The microstructures were analyzed using optical microscopy (OM) and scanning electron microscopy (SEM) to characterize the morphologies of both Fe- and Co-based coatings and analyze the exposed products along the surface and cross-section of specimens. The results revealed that the high-chromium Fe-based coating protected the underlying substrate better than Co-based coating.

  • 306.
    Sadeghimeresht, Esmaeil
    et al.
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Markocsan, Nicolaie
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Nylén, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    Dizdar, S.
    Höganäs AB, Höganäs.
    Corrosion behavior of high-chromium Fe-based coatings produced by HVAF thermal spraying technique2015Conference paper (Refereed)
    Abstract [en]

    Fe-based coatings with different Cr content were prepared by high-velocity air fuel (HVAF) spraying on the surface of both carbon steel and stainless steel 304L. The corrosion behavior of the coatings were evaluated using polarization and electrochemical impedance spectroscopy (EIS) techniques in 3.5 wt.% NaCl solution. Microstructure of the coatings were evaluated by X-ray diffraction (XRD), optical microscopy (OM), scanning election microscopy (SEM), and Energy-dispersive X-ray spectroscopy (EDS) before and after corrosion testing. The experimental results indicated that Cr strongly increased the corrosion resistance of the coating. Furthermore, having an elemental composition closer to that of the substrate, the coatings showed lower susceptibility to galvanic corrosion, accordingly lower corrosion rate.

  • 307.
    Samuelsson, Axel
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Framtagning av utvärderingsmodell för mindre energiproduktionsanläggning2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today's society is in a constant need of energy to function. Heating and cooling of homes and workplaces, operation of house holding and industrial machines and much more. The energy used is often associated with electricity, but it does not necessarily have to be so. For the purpose of heating and cooling, low-value sources of energy, such as residues from the public sector, can be used with good economy and good environmental performance as a result.

    Ramboll Energy, in Vänersborg is consulted by customers for developing competent solutions for how buildings and processes will be supplied with energy. Ramboll have a good insight in finding the best solution to produce energy, but the amount of work for doing so can be reduced.

    The methods of producing energy are many and finding which one of the methods that is most optimal can be a resource-consuming process. Many factors and parameters are involved which all shall be linked to the customer's prerequisites and generate a result. Geo heating, district heating and pellet boilers do all have the capacity to deliver enough energy, to the customer, with a power requirement up to 10MW. The best way to suit the customer can be an assessment model.

    The empiricism that forms the basis of the model has been created by reading books, previous student essays and research reports, searching information on websites and by holding conversations with subject-oriented staff. The implementation phase for developing a model has been divided into parts, such as identifying requirements, effect- and economically limiting parameters, collecting associated costs and climate conditions. Furthermore, a model was created, where customer-specific values are to be entered and a result of which energy source is the best for customer is generated.

    The model has been divided into three parts - a checklist with identified requirement parameters used as a course screening tool, a plant-size calculation tool, and a life cycle cost calculation tool with simplified life cycle analysis. The result has been verified with a number of different scenarios that, depending on the needs, delivered results that vary according to the need.

  • 308.
    Sandberg, Ulf
    University West, Department of Engineering Science.
    How an Enlarged Maintenance Function Affects the Performance of Industrial Maintenance and Maintenance Services2011In: Maintenance performance measurement and management, MPMM2011: 13-14 dec, Luleå / [ed] Galar d, Parida A, Schunnesson H, Kumar U, Luleå: LTU , 2011, p. 107-112Conference paper (Refereed)
    Abstract [en]

    Today, many companies struggle with maintenance work established by pre-requisites during purchasing, installation and start-up of plants, systems and machines. In search for improvements in existing maintenance organizations, it´s easy to conclude that they look like and is a direct consequence of previous engineering decisions and activities.

       Maintenance is, however, performed in the operation phase with weak coupling to what created it. Using an empirical knowledge base, several examples of this narrow view on maintenance is given along with the consequences it results in today.

       It is argued, that the increasing need to create and preserve knowledge will be the driver for change and the main contribution to an enlarged and more efficient maintenance function. Improvements are pointed out using references to the leading actors creating the frontier today where most companies could be tomorrow. The paper hopefully will contribute to how maintenance processes and activities are being designed, set-up and carried out.

  • 309.
    Schelin, Erik
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Larsson, Filip
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Effektivisering av materialflödet med hjälp av  materialförflyttningskoncept på Bodycote i Angered2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Bodycote in Angered works with heat treatment and surface treatment of steel components. Bodycote aims to keep up with the industrial development and are therefore exploring opportunities to automate parts of the workshop. The company is a processing company where deliveries consist of products that will return to the supplier. Bodycote has identified the time the operators put on transporting goods in the material flow as unnecessarily large, in the next step, they want to explore the possibility of streamlining the material flow. The objective with this study is to investigate the concepts that are relevant to freeing time for operators regarding the material transfer. The remaining concepts are investigated to ultimately be tested in an investment assessment, the idea of which is to serve as a basis for decisions regarding the introduction of a new material transfer concept. This study follows the DMAIC methodology, which is a method to ensure that the problem is correctly understood, that the problem solving is based on facts, the root causes are identified and that effective solutions remains. For the collection of results-based data, methods such as value flow analysis, spreadsheets, subdivisions in to product families etc. are used. After the concepts were assessed in terms of criteria and weighting, which were set according to Bodycote's prerequisites and requirements, two concepts were kept that were passed on to investment assessment, the concepts were automatic trucks and product trains. Some concepts that are generated, which do not meet the criteria equally well, may need to be used as a partial solution when introducing a new material transfer concept, especially the layout improvement proposal.   

  • 310.
    Sefton, Martin
    University West, Department of Engineering Science.
    Ständiga förbättringar och praktisk problemlösning: en explorativ studie på Saab Automobile AB2009Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Continuous improvement is one of five principles in General Motors – Global Manufacturing System (GM-GMS). GM-GMS has been used by Saab Automobile AB since 2003 and is a central component for realisation of GM’s vision. Internal audits have discovered problems with one of the tools, practical problem solving (PPS), which needs to be improved. The department manufacturing of press and body (PK) wants to survey the problems and initiate a process of improvement. The purpose of this thesis work is to develop a foundation for future re-designs of the PPS process. Employees have been interviewed and observed in order to explore possible difference theoretical and practical problem solving with PPS. The result of the investigation shows 4 different and interrelated problem categories. 1. Information transfer, PPS hand over to product quality engineers (PQE) department cause problem when general assemblies (GA) are excluded from the improvement work. General assemblies do not get any feedback information from (PQE) about planed countermeasures. 2. Problem solving, team leaders has difficulties with identifying the true problem. Using “five-why” during the analysis work causes problem, since team leaders do not have the knowledge of how to use the tool in a proper way. 3. Documentation of PPS, the content in the PPS-form is a problem according to team leaders. Lack of knowledge and understanding of how to use the PPS-document leads to incomplete and incorrect analysis. 4. Coordination of involved people, support and help are missing from the management and quality engineer according team leaders. PPS from Global Costumer Audit are imposing time stress according to team leaders. Recommendations for further work is to investigate the opportunities with a web based PPS and process to improve information transfer and documentation of PPS. A second recommendation is to train and coach team leaders in problem solving and improve coordination of involved people and skills in problem solving.

  • 311.
    Segerstark, Andreas
    University West, Department of Engineering Science, Division of Mechanical Engineering.
    Weld head motion control of girth and tubular joint welding simulations in LS-DYNA2013Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The basis for performing a thermo-mechanical staggered coupled heat source analysis of a welding simulation is implemented into LS-DYNA. In this report, three methods for initiating the heat source’s mechanical motion during girth and tubular joint welding are developed and evaluated. The first method is a reformulation of the equations used at Det Norske Veritas, the second is an incorporation of the equations into excel and the third is a standalone third party software. The most efficient of the developed methods turned out to be the software which creates k-files which are implemented into the main k-file using LS-PrePost. All methods have been visually and numerically evaluated using Excel, LS-DYNA and LS-PrePost.

  • 312.
    Severinsson, Markus
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Perstedt, Ida
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Lindström, Martin
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Development of a Titanium Outlet Guide Vane with Honeycomb Core2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    GKN Aerospace Sweden develops and manufactures engine components for the aerospace industry. One of these components is the outlet guide vane (OGV) which, in a set of several, constitutes the mechanical connection between the core structure and fan case of the Fan statics. The aerodynamic application of the OGV is to redirect the airflow from the fan.

    An important goal for the aerospace industry is to develop fuel efficient engines with as little carbon dioxide emissions as possible. A weight reduction of the engine is an approach to reach the above mentioned goal. The weight can be reduced by component design or by using a material with a high strength-to-weight ratio.

    During this bachelor thesis, the scope was to develop a titanium outlet guide vane with honeycomb core through concept maturation, welding evaluation and strength analysis. The material properties and behavior of the honeycomb panel was investigated through drop weight testing, modal analysis and high cycle fatigue.

    The results are summarized in a proposed final concept, referred to as the honeycomb OGV. A comparison between the price of the honeycomb OGV and the present market value of an OGV subjected to lowest loading shows that the honeycomb OGV is currently more expensive. However, the relatively high strength combined with the comparatively high cost makes the honeycomb OGV suitable for placement in the part of the Fan statics subjected to highest loading.

    The welding processes evaluation showed that resistance welding and laser beam welding are two joining methods for joining of the honeycomb OGV.

    The honeycomb panels have shown a remarkable high strength throughout the practical tests and can therefore be considered as an interesting alternative in lightweight and high strength designs.

  • 313.
    Sikström, Fredrik
    et al.
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Ericsson, Mikael
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Christiansson, Anna-Karin
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Niklasson, Kjell
    University West, Department of Engineering Science, Division of Process and Product Development.
    Tools for simulation based fixture design to reduce deformation in advanced fusion welding2008In: Intelligent Robotics and ApplicationsLecture Notes in Computer Science Volume 5315,  2008: First International Conference, ICIRA 2008 Wuhan, China, October 15-17, 2008 Proceedings, Part II / [ed] Youlun Xioun, Springer, 2008, Vol. 5315 LNAI, no PART 2, p. 398-407Conference paper (Refereed)
    Abstract [en]

    The traditional fusion welding and fixture simulations are performed using advanced finite element simulation tools, commonly used are e.g. MSC.Marc, ANSYS, ABACUS and COMSOL Multiphysics. These simulations are made one at a time and separately due to heavy calculation load for each case. Such an approach does not give a full description of the integrated work piece and fixture behaviour. We propose a strategy to decrease the computational time and solve the problem accurately enough for industrial needs. Focus of the simulation result is on residual deformation. The work piece is a simplified component composed by metal sheets, and rigid and loose clamping was investigated. Simulation results give the size of forces and deformations in the clamped edge. Deformation measurements are performed using 3D-scanning of the work piece after cooling and released from fixture, same situation as in the FE-simulations. The proposed strategy has shown to be useful and is industrially competitive due to reduced engineering manpower, computation time, and need for practical experiments. The strategy is to use full off-line programming where computer aided robotics for weld sequencies is integrated with finite element modelling in order to obtain weld parameters and fixture design.

  • 314.
    Sikström, Fredrik
    et al.
    University West, Department of Technology, Mathematics and Computer Science, Division for Electrical Engineering and Land Surveying.
    Ericsson, Mikael
    University West, Department of Technology, Mathematics and Computer Science, Division for Electrical Engineering and Land Surveying.
    Nylén, Per
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Christiansson, Anna-Karin
    University West, Department of Engineering Science.
    3D-Scanning for Weld Distortion Measuring2006In: Instrumentation and Measurement Technology Conference, 2006. IMTC 2006. Proceedings of the IEEE, IEEE conference proceedings, 2006, p. 2132-2137Conference paper (Refereed)
    Abstract [en]

    Optical three dimensional scanning for weld distortion measurements have been performed for validation, inspection, general visualization and documentation of a robotized welding process. The planning, preparing and processing of the weld is done in a simulation-based concept where computer aided robotics software simulations are integrated with finite element analysis simulations with the objective to reduce global geometrical deformation during welding. The off-line programmed robot paths were used as an input for finite element calculations of temperature fields and distortion in the work piece. In order to validate the finite element model 3D-scannings have been performed before and after every single welding sequence. This paper describes a validation experiment with non-contact measurements of weld distortion and discusses limitations in optical 3D-scanning techniques used for this purpose

  • 315.
    Sikström, Fredrik
    et al.
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Nilsen, Morgan
    University West, Department of Engineering Science, Division of Automation Systems.
    Eriksson, Ingemar
    GKN Aerospace, Trollhättan, Sweden.
    Optical Methods for In-Process Monitoring of Laser Beam Welding2014In: Proceedings of the 6th International Swedish Production Symposium 2014 / [ed] Stahre, Johan, Johansson, Björn & Björkman, Mats, 2014, p. 1-9Conference paper (Refereed)
    Abstract [en]

    This paper addresses the issue of evaluating and selecting optical sensors to be integrated with a 1μm laser beam welding system. The method used for this evaluation is mainly a survey of relevant research litterature. The result of this work is a matrix showing the different methods and distinct features related to relevant process conditions that can be estimated or detected with respective methods. This evaluation also includes considerations on the required sensor bandwidth in relation to inertia and time constants in the physical process.

  • 316.
    Sikström, Moa
    et al.
    University West, Department of Engineering Science.
    Wisén, Nathalie
    University West, Department of Engineering Science.
    Metodutveckling av virtuella byggnationer på Saab Automobile AB2010Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Saab is in need of an improved method for construction of virtual buildings that the planner can utilize. By creating a process structure in the existing PLM system, that can communicate and consume data from the product structure that already exists, a lot of work could be saved. Presently, the planner uses a visualization program that is connected only to the product structure. The current method with this visualization software is that the planner builds a process structure for each and every new project gate. This structure cannot easily be updated and therefore a new structure must be created before the new project gate. Thus, the virtual builds become resource inefficient.

    By creating a process structure that easily can be updated, the structure could be reused in new gates and projects. This is consistent with the basic ideas behind using a PLM system. There are several obstacles to master before this will be possible. 

    The conclusions of this study are that in the process structure, the articles should be placed under the stations and operations where they are mounted in the actual factory. There is no universal solution as to how the structure should be, but it should reflect the plant processes. In order for the planner to easily take advantage of this structure, it should also be possible to look up articles using a name filter.

    Planners are currently responsible for particular product areas, such as safety related articles. All parts of this product field are installed in separate sections in the plant. In order to efficiently find all the articles in the process structure, the operations should be named after the articles that are assembled under the specific operation.

    A temporary working method has been proposed and the instructions can be found in Appendix B.

  • 317.
    Singh Handa, Sukhdeep
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Precipitation of Carbides in a Ni-based Superalloy2014Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Alloy B is relatively new precipitation hardening superalloy. It´s applications are in the hot sections of the aero engines, rocket nozzles, gas turbines and in the chemical and petro-leum applications. The alloy is characterized by keeping high strength at elevated tempera-tures and high creep resistance. It´s excellent mechanical properties and corrosion resis-tance are due to the balanced amount of the coherent γ' matrix, combined with other alloy-ing elements and carbides.

    There are three types of carbides which can be found in nickel-based superalloys: MC, M

    23C6 and M6C. Primary MC carbides act as source of carbon for the secondary carbides, which precipitate at the grain boundaries. They can have strengthening effect by hindering the movement of dislocations.

    In this work both simulation and experimental analysis are conducted in order to investi-gate the behaviour of the secondary carbides. JMatPro simulation is used to predict the behaviour of the material. Heat treatments are conducted at soak temperatures ranging from 920 °C to 1130 °C, with steps of 30 °C, and dwell times of 0.5, 1, 2 and 24 hours. Experimental methods included analysis at LOM, SEM, EDS, manual point counting and hardness tests.

    Main results show chromium rich M

    23C6 carbides are stable at lower temperature compared to molybdenum rich M6C. Both appear as fine and discrete particles at the grain boundaries at 1070 °C. This morphology is believed to be beneficial for the mechanical properties of the alloy. The volume fraction varies between 0.6 and 1.3%. Hardness values are relevant in the range of 920-1010 °C. Above this range there is sudden drop of the hardness

  • 318.
    Singh, Vivek
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Tuovinen, Johnny
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Konceptutveckling av säkra snabbfästen för grävskopor2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis work was carried out for a firm that manufactures and sells attachments and buckets for excavators. The work is performed as a product development project at University West. Since there have been a number of accidents where buckets of the type produced by the company have fallen from quick couplers, it is now required to review the design of the quick coupler. The project started with a study of why accidents with dropped buckets occurred. It turned out that all the accidents studied had been due to that the wedge lock was closed the wrong way. After the initial literature study, the work to establish customer requirements began. Problems were listed and broken down into subproblems. After this step solutions were generated to the subproblems by using brainstorming, Triz effect database and Triz 40 principles. Through patent and competitive analysis a basis for concept generation was created, which started with brainstorming. When concept generation was done then concept screening and concept scoring was used for selecting a concept.

    An FMECA was performed on today's quick coupler before the new construction was drawn in CAD and then an FMECA was performed on the new construction. The FMECA showed that many of the risks found on the original design were eliminated in the new design. Finally the new design was tested using FEM analysis where it was compared with a corresponding simulation of the original design. Thereafter an analysis was performed as a simulation of the forces operating in different directions. The simulations showed that the new design is at least as good as the original design and no major changes needed to be made. The result was a quick coupler similar to the original design, but has wedge locks at both ends of the quick coupler and an indicator that shows if the coupler has the correct position towards the bucket before locking the wedge lock. In the report result chapter the final selection of the concept is presented in more detail.The approach of Ulrich and Eppingers description of product development has worked well. It is a structured model to follow that deliver a result based on customer requirements.

  • 319.
    Sjöstedt, Jacob
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Magnusson, Daniel
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Konceptutveckling av ljud- och vibrationsreducering för scrollkompressor i en elektrisk bil2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta examensarbete har utförts under tio veckor på ÅF Automotive i Trollhättan med syftet att reducera det hörbara ljudet för passagerarna i en elektrisk bil. Huvudproblemet är att kompressorn i klimatanläggningen genererar luftburet ljud och vibrationer vilket leder till en försämrad komfort för passagerarna. ÅF Automotive ska köpa in en ny kompressor och önskar en kravspecifikation innehållande ljudkällorna i en scrollkompressor samt riktlinjer för hur effekterna från dessa kan reduceras. Denna kravspecifikation ska senare användas som beslutsunderlag till förhandlingen. Koncept i form av komplement till scrollkompressorn ska utvecklas som reducerar luftburet ljud och vibrationer från varje identifierad ljudkälla.För att genomföra arbetet på ett systematiskt sätt har metoder och verktyg lämpade för konceptutveckling använts. Ljudkällorna i scrollkompressorn identifierades genom att utföra observationer, intervjuer och litteraturstudier. En kravspecifikation på de identifierade ljudkällorna upprättades därefter. Genom att tillämpa en generisk produktutvecklingsprocess utvecklades flera koncept för att reducera ljud och vibrationer från de identifierade ljudkällorna. För att finna de bästa koncepten utfördes konceptval innefattande multiröstning,beslutsmatriser och mer djupgående analyser vilka behandlar risk för patentintrång, miljöpåverkan, ljudreduceringsförmåga, monterbarhet, säkerhet samt kostnad. Fyra koncept; fjädrar, gummibussningar, hårt skal och mjukt skal valdes då de reducerar ljudet i passagerarutrymmet och presterade väl under den djupgående analysen och är därför värda att vidareutveckla. Hur mycket ljud de kommer att reducera har inte specificerats. Detär nu upp till ÅF Automotive att göra ett val över vilka koncept som de vill vidareutveckla. Koncepten är fortfarande på en generell nivå och måste anpassas specifikt till den scrollkompressor som väljs att köpas in. Koncepten har endast utvecklats för att reducera ljud och vibrationer och det finns fortfarande osäkerheter som kommer behöva behandlas i framtiden.

  • 320.
    Steffenburg-Nordenström, Joachim
    University West, Department of Engineering Science, Research Enviroment Production Technology West. GKN Aerospace Sweden.
    The evolution of residual stresses in a stress relief heat treatment of test specimen of alloy 7182016In: Mathematical Modelling of Weld Phenomena 11 / [ed] S. Sommitsch, N. Enzinger, P. Mayr, Graz, 2016, Vol. 11, p. 331-343Conference paper (Refereed)
    Abstract [en]

    Manufacturing of aero engine components requires attention to residual stress and final shape of the product in order to meet high quality product standards. This sets very high demands on involved manufacturing steps to meet design requirements. Simulations are used to assure the latter. This requires an appropriate model to account for stress relaxation. The study is part of a project where the aim is to simulate a chain of manufacturing steps e.g. forming, welding and heat treatment. The focus in this paper is on the stress relaxation during the heat treatment step. It is imperative to have relevant data for calibrating this part of a constitutive model.  A test procedure resembling the real conditions in the manufacturing chain is proposed. Tests were carried out on test specimens made of Alloy718 and used to calibrate a constitutive model. Comparisons between experimental and simulated results showed very good agreement.

  • 321.
    Steffenburg-Nordenström, Joachim
    et al.
    University West, Department of Engineering Science, Research Enviroment Production Technology West. GKN Aerospace Sweden.
    Pérez Caro, Lluís
    IUC, Olofström, Sweden.
    Odenberger, Eva-Lis
    IUC, Olofström, Sweden.
    Oldenburg, Mats
    Luleå University of technology, Luleå, Sweden.
    Svensson, Lars-Erik
    University West, Department of Engineering Science, Division of Welding Technology.
    Comparison of forming, welding and heat treatment simulations in LS-DYNA and MSC Marc2016In: Proceedings of 10th International Conference on Trends in  Welding Research & 9th International Welding Symposium of Japan Welding, American Welding Society (AWS) & Japan Welding Society (JWS) , 2016, p. 660-663Conference paper (Refereed)
    Abstract [en]

    The manufacturing of components for aero engine structures from a flat sheet to the final shape usually requires several steps that may introduce residual stresses and shape distortions in the part. Depending on the magnitude, sign and distribution with respect to the stresses induced by the service load, the remaining stresses may affect the service life of a component, especially when submitted to cyclic loading. Nowadays, several types of software that have the ability to predict the residual stresses and the final shape of a component subjected to various process steps are available. However, literature shows a lack of comparison studies among different software tools for multi-step simulations of a manufacturing process. In this study, the manufacturing process chain of an aerospace component including forming, welding and heat treatment in the nickel-based superalloy 718 is modelled and simulated using the two finite element software codes LS-DYNA and MSC.Marc. The results from the displacement of the blank in the punch stroke direction, the equivalent plastic strain and the von Mises stress are compared between both FE codes. The displacement of the blank after forming is slightly higher in LS-DYNA compared to MSC.Marc, as well as the equivalent plastic strain and the von Mises stress values. This tendency is also observed after trimming and welding. It can also be noted that the distribution of both strains and stresses on the trimmed and welded parts varies between the two compared codes, presumably due to the choice of different solver options, explicit and implicit.

  • 322.
    Steffenburg-Nordenström, Joachim
    et al.
    University West, Department of Engineering Science, Research Enviroment Production Technology West.
    Svensson, Lars-Erik
    University West, Department of Engineering Science, Division of Welding Technology.
    Simulation and Validation of Forming, Milling, Welding and Heat Treatmentof an Alloy 718 Component2017In: International Journal of Materials Forming and Machining Processes IJMFMP), ISSN 2334-4563, Vol. 4, no 2, p. 15-28Article in journal (Refereed)
    Abstract [en]

    This paper describes finite element simulations of a manufacturing process chain consisting of

    forming, weld preparation by milling, laser welding and stress relief heat treatment of an alloy 718

    aero-engine part. The work also includes experimental validation with optical measurements of the

    part after each process step. Approximation and discretization errors were avoided by keeping the

    same mesh and constitutive model. The results show that the remaining stresses affect the subsequent

    manufacturing process step and therefore, simulation of the process chain is essential. The accuracy

    with respect to the geometry showed relatively good agreement between measurement and simulation.

  • 323.
    Stridh, Peter
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Konstruktion av mekaniskt lyftdon2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report is the result of a thesis work and describes the development of a standardized gripping device. The gripper had to lift and let go of the object only by lifting it up or place it down. It had to be completely mechanical and handle a load up to 75 kg. The requirement was to produce gripper device with laser cut parts with as small manufacturing time as possible and that the components would not cost more than 800 kr.

    At first various types of grippers were studied at the company and later on the studies continued on the Internet. At the same time simple sketches were made on different concepts. Some of the sketches were made as models in CAD. A concept was chosen and further developed. One of the improvements was that the gripping arms was given parallel movement instead of radial and with a stronger gear compared with a regular scissors gripping device. The correct dimensions for the components were calculated and a final CAD model was created. Out of model the drawings were made and a prototype was manufactured.

    The prototype was assembled and tested and the gripper lifted the object as it should. The locking mechanism opened and closed as it should. The gripper was tested to meet two times the safety with no plastic deformation. A load test was made where the prototype managed to take a load over 150 kg which is approved. After that the prototype was tested, there were a few changes to improve the function and to reduce the price. The cost of the components was 920 SEK but compared to the company's other lifting devices it was not very expensive.

    The conclusion of the work was that the functional requirements were met and that the gripper works.

  • 324. Sudarshan, T.S.
    et al.
    Nylen, PerUniversity West, Department of Engineering Science, Division of Production Engineering.
    Surface Modification Technologies XXII: Proceedings of the Twenty Second International Conference on Surface Modification Technologies  Held at University West, Trollhättan, Sweden September 22-24, 20082009Conference proceedings (editor) (Other academic)
  • 325.
    Svensson, Bo
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Optimisation of Manufacturing Systems Using Time Synchronised Simulation2010Licentiate thesis, comprehensive summary (Other academic)
  • 326.
    Svensson, Bo
    et al.
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Improving Performance in Flexible Manufacturing by a P-sop Approach2014In: Proceedings of the 6th International Swedish Production Symposium 2014 / [ed] Stahre, Johan, Johansson, Björn & Björkman, Mats, 2014, p. 1-8Conference paper (Refereed)
    Abstract [en]

    This paper present a Part oriented Sequence of Operation (P-SOP) approach that address flexibility, robustness and deployment in manufacturing cells up to plant level. A P-SOP description language has been formulated where the control strategy based on actual circumstances easily can be defined. Furthermore, a P-SOP multi-agent generator has been created that compiles the strategy description to multi-agents that control the manufacturing. Deadlock free IEC 61131-3 PLC code are directly generated from the description language. The code is not optimised for a specific scenario since the general description contains all possible routing paths and all resources available.

  • 327.
    Svensson, Bo
    et al.
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Off-Line Parameter Tuning of a Sheet-Metal Press Line2011In: The 4th International Swedish Production Symposium, Lund: Swedish Production Academy , 2011, p. 459-466Conference paper (Refereed)
    Abstract [en]

    Anautomotive sheet-metal press line is an excellent example of an automatedmanufacturing system with time dependent complex control functions. The PLCcontrol functions include not only discrete events and supervisory control, butalso analogue feedback and motion control. Furthermore, most press line tuningmethods today are on-line and highly empirical, depending on individualoperators. Thus, there is a need of an objective off-line parameter tuningmethod. This paper presents an off-line parameter tuning of an automotivesheet-metal press line. Improved production performances have been reached,both in terms of increased production rate and smoother robot motions, comparedto today’s industrial on-line method. Two suitable optimisation algorithms havebeen implemented and evaluated. The challenge is to handle highly non-linearfunctions, considerable number of parameters, and long evaluation times in thesimulation. The utilised off-line method is a combination of simulation basedoptimisation and time synchronised hardware-in-the-loop simulation, i.e. avirtual manufacturing system including real PLCs. This method provides adistinct advantage, since it describes all complex control functions byexecuting the same PLC control code used in the manufacturing plant. A furtherbenefit is that all tuned process parameters can be directly transferred to themanufacturing plant.

  • 328.
    Svensson, Bo
    et al.
    University West, Department of Engineering Science, Division of Automation Systems.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Automation Systems.
    P-SOP -€“ A multi-agent based control approach for flexible and robust manufacturing2015In: Robotics and Computer-Integrated Manufacturing, ISSN 0736-5845, E-ISSN 1879-2537, Vol. 36, p. 109-118, article id 1301Article in journal (Refereed)
    Abstract [en]

    In a truly flexible manufacturing system the description of the control strategy must be updated every day. Hence, a new way to handle changes in the environment down to control system deployment and production is required. This paper presents a novel approach, based on P-SOP, to handle multi-agent based control and verification. The P-SOP approach addresses flexibility, robustness and deployment in the best possible manner with the least waste of time and effort. P-SOP includes a description language where the control strategy based on actual circumstances easily can be defined. Based on the description multi-agents, to control the manufacturing, are automatically generated. An industrial advantage is that the multi-agent generator creates IEC 61131-3 PLC code that can be executed on standard PLC’s. This feature eliminates the need for experts in PLC programming and reduce deployment time to become more efficient. Hence, this flexibility enables small series down to one off production in a competitive way. With multi-agent control it is also possible to handle rebalancing due to market changes, scheduling of available humans, introduction of new part types, and rerouting due to a machine break down or planned service. The generated agents are not optimised for a final solution with specific timings. All decisions are made on-line and the generated solution adapts to the circumstances that arise. With the P-SOP multi-agents it is easy to manually remove or introduce parts to the manufacturing cell without disturbing the system, e.g. for manually random inspections, removal of parts due to restart. The formulated description language and the multi-agent generator has been successfully tested and evaluated in an industrial environment.

  • 329.
    Svensson, Bo
    et al.
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Lennartson, Bengt
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    A Virtual Real-Time Model for Control Software Development: applied on a Sheet-Metal Press Line2005In: Industrial Simulation Conference 2005 / [ed] Jörg Kruger, Alexei Lisounkin, Gerhard Schreck, 2005, p. 119-123Conference paper (Refereed)
  • 330.
    Svensson, Bo
    et al.
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Lennartson, Bengt
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Off-Line Optimisation of Complex Automated Production Lines: Applied on a Sheet-Metal Press Line2007In: Proceedings of the 2007 IEEE International Symposium on Assembly and Manufacturing, IEEE , 2007, p. 82-87Conference paper (Refereed)
    Abstract [en]

    This paper presents a successful off-line

    optimisation case study of a sheet-metal press line for the

    automotive industry. The proposed off-line optimisation

    method results not only in increased production rate but also in

    obtaining smoother material handling motions. The off-line

    optimisation method contains two parts. The first part is a

    parameter study, combining factorial design with production

    line simulation including emulated control systems and

    resulting in a simplified performance model based on multiple

    linear regression. The second part is an optimisation on the

    simplified performance model using the Nelder Mead simplex

    method aiming at production optimisation. Due to the

    complexity in a modern production line, it is not possible to

    create a useful model representation of the entire control

    system code/function. Therefore, the proposed optimisation

    method is based on using production line simulation including

    emulated control systems with the real IEC 61131-3 control

    code. Our approach in this work is a parameter variation

    strategy for optimisation, i.e. adjusting the control system

    parameters in the same way as the line operators do, and not

    changing any control strategy.

  • 331.
    Svensson, Bo
    et al.
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Lennartson, Bengt
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Time-synchronised hardware-in-the-loop simulation - Applied to sheet-metal press optimisation2012In: Control Engineering Practice, ISSN 0967-0661, E-ISSN 1873-6939, Vol. 20, no 8, p. 792-804Article in journal (Refereed)
    Abstract [en]

    This paper presents an off-line process parameter tuning method, focussing on complex control functions for automated manufacturing systems. The proposed method is based on a combination of simulation-based optimisation and time-synchronised hardware-in-the-loop simulation. Real indus- trial control systems, e.g., PLCs, are included in the simulation, executing the unchanged control code from the manufacturing plant. This approach allows all plant control functions to be included, even time-critical feedback loops and vendor secret blocks such as motion control. Consequently, the method suggested manages the problems identified in previously presented simulation-based approaches. Furthermore, a case study of an automotive sheet-metal press line has been performed to verify the proposed method, with successful results.

  • 332.
    Svensson, Lars-Erik
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    Karlsson, Leif
    University West, Department of Engineering Science, Research Enviroment Production Technology West.
    Harati, Ebrahim
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Increasing fatigue life using Low Transformation Temperature (LTT) welding consumables,2013In: 2nd Swedish conference on design and fabrication of welded structures: Conference proceedings / [ed] Zuheir Barsoum, Stockholm, 2013, p. 49-64Conference paper (Other academic)
  • 333.
    Svensson, Thomas
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Åhs, Christian
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Kartläggning av kritiska maskiners utrustningseffektivitet2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is comprised of an investigation of equipment effectiveness at the company Produce AB (fictitious name) at two machine cells, Alfa, which consists of four millers and Beta, which consists of four lathes. The company is a subcontractor of metal products to three different business areas and consists today of 100 employees. By measuring the actual time the machinery process goods for the customer the company have identified low machine utility as a problem in the production. With this investigation, they therefore want to identify the causes of this problem in order to improve the business and become more competitive. The approach for this investigation is based on the methodology within Six Sigma where the DMAIC model has been used. Quantitative data collection occurred during ten days with the use of an operator template, where duration and cause of machine downtime was noted. Qualitatively, unstructured, semi-structured and fully structured interviews have been used to analyze the root causes for machine downtime that was identified following the quantitative data collection. The main part of the theoretical framework for this thesis includes total productive maintenance and overall equipment efficiency, which was used to map and calculate the current state of the equipment efficiency. Other theoretical frameworks are Lean, material- and production planning, resource utility and variations. These theories were used to analyze the result and give suggestions for improvement. The calculated equipment efficiency varies between both the cells and the machines within the cells. In the Alfa-cell, values vary between 52 and 80 per cent and in the Beta-cell between 37 and 57 per cent. The significant causes for machine downtime were identified as lack of personnel, long set-up times, machinery waiting for operators, differences in processing time between cycles and machine breakdowns. From this, suggestions for improvement were developed. The suggestions included employment of addition personnel, reduction of set-up times, introduction of an Andon-system and elimination of processing time differences. In general, the authors of this thesis can see that the company has a will to improve, but the work with improvements has been suffering since the production is behind, compared to what the customer demands. A lack of resources and short term-thinking are therefore considered two of the things that most affect the company's possibilities to maintain a competitive business.

  • 334.
    Svenungsson, Josefine
    et al.
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Choquet, Isabelle
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Kaplan, Alexander F.H.
    Luleå University of Technology, Department of Engineering Science and Mathematics, 971 87 Luleå, Sweden.
    Laser Welding Process: A  Review of Keyhole Welding Modelling2015In: Physics Procedia, ISSN 1875-3892, E-ISSN 1875-3892, Vol. 78, p. 182-191Article in journal (Refereed)
    Abstract [en]

    Laser welding is used in several industrial applications. It can be distinguished between conduction mode and keyhole mode welding, between pulsed wave and cw laser welding and between CO2-lasers with a wavelength of 10 μm and various laser types of about 1 μm wavelength. A deeper understanding of laser welding allows improving weld quality, process control and process efficiency. It requires a complementary combination of precise modelling and experimental investigations. The here presented review focuses on modelling of laser keyhole welding, for both wavelength regimes. First, the fundamentals of the laser welding process and its physics such as beam propagation, keyhole formation and melt pool dynamics are addressed. The main approaches for modeling energy transfer from laser beam to keyhole surface as well as fluid flow in the material are then discussed. The most relevant publications are systematically structured, particularly categorized with regard to the respective physical phenomena addressed. Finally some open questions are underlined.

  • 335.
    Sylvén, Julius
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Evaluation of heavy duty diesel engine coolant pumps2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this time of environmental awareness and corporate social responsibility, it is vital for companies to offer environmentally friendly products or services in order for the companies to be competitive. Being one of the largest truck manufacturers in the world, Volvo Trucks is obligated to follow this trend. The biggest drawback with a truck in an environmental perspective is its pollutants and carbon dioxide emissions. A major variable when reducing emissions is the fuel consumption. Trucks are used for transport and run day and night, often for very long distances. It is safe to say that even a very small reduction in fuel consumption has a major impact on both the fuel economy and the environmental impact over the truck's lifetime.

    This report consists of a comparison made of a fixed coolant pump and a 2-speed clutch pump. A fully variable clutch pump was also meant to be tested but was not, due to limited resources. The aim was to determine the best alternative to proceed with regarding fuel economy, which is the ultimate goal for Volvo Trucks.

    The test results are not reliable because of major mechanical errors due to flaws in the test equipment used. This report works as a basis for continued research regarding clutch performance. However, from the results given it is clear that a controllable coolant pump clutch is the right field of study to continue researching since it has great power saving possibilities.

  • 336.
    Söder, Heléne
    University West, Department of Engineering Science, Divison of Natural Sciences, Surveying and Mechanical Engineering.
    Implementering av kvalitetsinspektion med kamera2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study was conducted at Dahréntråd in the spring of 2014. At Dahréntråd round and squared winding wire is enameled. During this process enamel lumps can appear which can cause complaints from customers. On two horizontal machines for enameling square wire two lump indicators with cameras were installed before this study was initiated. The pur-pose of this study was to study the lump indicators, propose improvements to them and to create a plan for implementing them as well as a work description on how to handle them when implemented. The goal was for Dahréntråd to be able to use this study as a basis to successfully implement the system on all twelve machines in the machine park.

    The study was carried out according to Gershon et. al. [6] view on improvement work. The first step, to define which process to improve on, was performed by Dahréntråd before the start of this study. The second step, to study the conditions of the process and produce suggestions for improvements of the process, corresponds to the situation analysis and the improvement work performed during this study. The third step, to implement the im-provements, falls outside of the time frame of this study and will be performed by Dahréntråd.

    The situation analysis consisted of interviews and observations of relevant personnel. The result was an identification of improvement possibilities. These possibilities were the foun-dation of the improvement work which was conducted as a concept generation process. The result of the improvement work was the following improvement proposals:

    • To generate a signal to the operator's pager when a lump is detected.

    • To install a screen with the history of all twelve machines.

    • To shorten the previous cooling system and add a lid to it.

    • To change the placement of the cooling system.

    • To include the lump indicators in to the existing process control of the machine park.

    • To define and evaluate the systems boundaries for detecting lumps.

    • To produce a gauge block for assessments of lumps.

    A work description according to Dahréntråd's existing ones has been produced as well as an implementing plan for the improvement proposals

  • 337.
    Söderblom, Robin
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Jonsson, Staffan
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Feasibility study for implementation of automotive measuring method in aerospace industry2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis comprises an investigation in order to find possibilities to implement the method used in the automotive industry to automatically generate a collision free measurement program within the aircraft components manufacturer. The purpose with the study was to compare and analyse the different methods used to generate measurement programs at GKN Aerospace Engine Systems in Trollhättan, National Electric Vehicle Sweden (NEVS) and Volvo Cars Corporations (VCC).The study was conducted through meetings, observations and questionnaires with staff from the geometry assurance engineering (GAE) departments and measurement departments in each company. By mapping the virtual GAE process started from concept development in CAD to the measurement phase in which components are measured in coordinated measuring machines (CMM), a chain of activities was analysed.NEVS and VCC are today using RD&T and IPS to generate optimized CMM programs in which a time efficient measurement path can be generated. This method was compared with the current approach at GKN Aerospace where they use one supplier for offline CMM programming (OLP) software solutions and CMMs. They are thereby working in a closed system where the OLP communicates with the CMM by supplier specific methods. The automobile manufacturer NEVS and VCC, in contrast, uses a DMIS protocol which is an ISO and ANSI standard.The study shows that an implementation of the software used by the Swedish automobile manufacture NEVS and VCC at GKN Aerospace in Trollhättan, may not have any significant improvements regarding time savings and thereby no economic benefits. However, the approach for generating an optimized measurement program in RD&T and IPS may have major improvements in other facilities within the aerospace industry which has also resulted in an instruction manual to be used for potential implementation.

  • 338.
    Tallian, Mattias
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Konstruktion av växel till arborrstång med vandrande huvud2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Most industries are dependent on large machines to carry out their activities. If these machines brake down or for some other reason are taken out of service it quickly leads to large consequential costs in the form of delays, etc. It is therefore a top priority to avoid these shutdowns, and if they arise quickly fix the problem that caused it. The problem with all types of maintenance and repair work on these machines is that they are too large to move to a workshop that has the necessary resources to fix the problem. To perform this type of maintenance and repair work must thus the resources required to address the problems moved to the place the machine is located.

    The equipment required for these types of jobs must often be tailored to fit each individual assignment. The designer is challenged to effectively develop a solution that takes all specific circumstances into account.

    Metalock Engineering Sweden AB is working with this type of repair work and has designed a line boring machine for line boring of bolt holes in large shaft couplings. Line boring is a process used to machine existing holes to precise dimension. Typical applications where line boring is required is these shaft couplings, but also bearing seats and machine leads requires precise holes with respect to the diameter and cylindricity. The machine that Metalock has constructed uses a mechanical gear drive for generating the power required for the power feed of the cutting head. This gear unit was developed under a very limited period of time. This resulted in an undeveloped gear unit with major operating problems that presents a direct safety hazard to the machine operator.

    The goal of this project was to construct a new gear unit that meet all the requirements regarding function- and safety. The work was carried out through a product development process and a study of the theory of mechanical transmissions, gears and bearings. Solution concepts where developed, and one concept was chosen for further development. From the chosen concept a gear unit which met all the specifications was constructed. The components of the gear unit were modeled using the CAD-program Autodesk Inventor. The components were then assembled in the CAD-program and used to carry out a verification of the gearbox kinematics.

  • 339.
    Tan, Ruoyo
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Protective coatings for Al press tools used in automotive industry2014Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The application of the thermally sprayed WC-Co and Cr 3C2-NiCr coatings have been widely used in industry for its superior sliding, abrasive and erosive wear properties. The Al2O3 coating possessing high hardness can be utilized to improve the wear resistance of the metallic surface. Replacing the stamping tool material from steel to lightweight aluminium with protective coatings offers significant gains such as reduction in power costs and increasing operational efficiency during manufacturing of sheet automobile parts. In this study, the WC-CoCr and Cr3C2-NiCr coatings were sprayed with High Velocity Air-Fuel (HVAF) process and Al2O3 coating was deposited using Atmosphere Plasma Spraying (APS) process. The coatings were evaluated and compared based on the results of roughness tests, hardness tests, adhesion tests, quantitative imaging analysis and microstructure analysis. The experimental results revealed that the roughness value varied in a lower range which implies of a high density of the coatings. It was found that coatings have an extremely high hardness value as tested by the Vickers hardness test. The WC-Co coating was found to be the hardest (1215.2HV). The adhesion test was implemented according to the ASTM C633-79 standard. The result showed that WC-Co and Cr3C2-NiCr coatings without a bond coat had high tensile strength, higher than the respective glue strength (63.54MPa, 75.89MPa). Whereas, the Al2O3 coating has a much lower tensile strength (15.2MPa, 25.68MPa, with and without bond) than others and using a bond coat layer does not contribute to an increase in adhesion strength of the cermet coatings. The coating thickness was evaluated using Light Optical Microscopy (LOM) and microstructure analysis was carried out using Scanning Electron Microscopy (SEM). From the microstructure analysis, it was observed that all the coatings have a dense microstructure, very low porosity and low oxide inclusions in top coat. The WC and Cr3C2 grains retain a large volume fraction of finely dispersed in matrix. The alumina coating was found to have low levels of un-melted or the re-solidified particles in the coating. All of the aforementioned analysis and results reveal that WC/CoCr and Cr3C2-NiCr coating show promising potential for press tool applications. However, abrasive resistance test still remained to be done and will be performed in the future. The result of it can reveal the actual wear resistance between two coatings in reality and will be helpful in determining the better protective coating for aluminium press tools

  • 340.
    Teke, Maysa
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Motion analysis of barge hulls2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Accelerations for three different barge geometries have been analyzed using diffraction solver GeniE/HydroD/WADAM. The analysis includes 5 different sea states simulated with JONSWAP spectra and 6 different headings with 45 degree spreading. Barge geometries are presented in section 5.3. One of the barges with modified geometry shows significantly reduced accelerations compared to original model. See section 6 for complete results. The table below summarizes the accelerations for the 3 barges

  • 341.
    Thelander, Marie
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Vernhamn, Sara
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Kvalitetsbristkostnadsanalys: Utförd på Borealis AB i Stenungsund2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The quality of a product can be defined as its ability to satisfy the customers’ needs and expectations or to exceed them, (Bergman & Klefsjö, 2010). To achieve this definition of quality the company needs to focus on quality development, which means constantly striving to develop the business processes. Increased profitability and sustainability can be achieved by focusing on quality development. It is important to pay attention to shortcomings and to understand the costs involved. This can be accomplished by performing a costs of poor quality analysis, which identifies problem areas and provide the conditions for efficient quality development in the areas where it is needed. A company with focus on quality development is Borealis AB. The company is located in Stenungsund and manufactures polyethylene in the shape of plastic pellets. After manufacturing, the plastic pellets are packaged by an automatic process in sacks. The manufacturing of sacks is a part of the packaging process and are made from tubular film. An analysis of costs of poor quality, regarding cassation, is performed in this study due to that an unknown quantity of tubular film is daily discarded. The aim of this thesis is to map the costs of poor quality regarding cassation and present improvement proposals, which can reduce or eliminate waste. Data collection were obtained by interviews, surveys, observations, measurements and existing data. The collected data has been obtained to enable an analysis of current situation, which clarifies that seven out of eight causes of waste occur in internal processes, storage in the outdoor warehouse, placement of rolls in the indoor storage area, setting of machine A and at the automatic change of roll in machine A. Total costs of poor quality regarding tubular film is estimated to approximately SEK 150 000 annually. This cost only refers to discarded tubular film and other types of cost and forms of waste, which are presented in this study, should also be considered.  The suggested improvements which enables reduced amount of waste are visual control, further development of the lay which enables stacking of pallets, lifting device at the packaging station, routines and standards, and an ergonomic lifting device to lift off bags from the conveyor. In addition to quality development and cost savings, the suggested improvements also reduce the source of waste, which has a positive effect on the company's sustainability work.   As a conclusion, the presented cost may, in a large international company, be perceived less significant, but it is the quality mindset within the company and not the size of the cost that determines future improvement work.

  • 342.
    Travis, Fred
    et al.
    Maharishi University of Management, USA.
    Lagrosen, Yvonne
    University West, Department of Engineering Science, Division of Process and Product Development.
    Creativity and Brain-Functioning in Product Development Engineers: A Canonical Correlation Analysis2014In: Creativity Research Journal, ISSN 1040-0419, E-ISSN 1532-6934, Vol. 26, no 2, p. 239-243Article in journal (Refereed)
    Abstract [en]

    This study used canonical correlation analysis to explore the relation among scores on the Torrance test of figural and verbal creativity and demographic, psychological and physiological measures in Swedish product-development engineers. The first canonical variate included figural and verbal flexibility and originality as dependent measures and (a) higher scores on the brain integration scale, (b) faster speed of processing in an event-related potential task, (c) faster conflict-resolution during the Stroop task, (d) higher moral reasoning, and (e) higher manageability and lower comprehensibility as independent measures. Flexibility and originality reflect the ability to see old situations in new ways leading to unique responses. Greater mental adaptability was associated with greater brain integration and speed of processing along with higher moral reasoning and feeling of being in control. Future research could investigate effects of interventions that optimize brain integration on creative output across professions.

  • 343.
    Tysse, Simon
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Utveckling av torkningsprocess för produkter av PEPP2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Fordonsbranschen står i nuläget inför många utmaningar att identifiera lösningar med hög prestanda för att klara av konkurrens i en global marknad. Cellplaster är en grupp material som är attraktiv för fordonsbranschen då de möter många av de höga krav som ställs. Exempel på sådana cellplaster är: expanderad polystyren (EPS), expanderad polyetylen (EPE) och expanderad polypropylene (EPP). Materialen produceras till ett granulat som sedan kan formgjutas med vattenånga. Slutresultatet är produkter med hög prestanda i stöttålighet, energiabsorbering och en mängd övriga egenskaper. Bewi Automotive formgjuter komponenter i EPP till Volvo Car Corporation, SCANIA trucks och ett flertal underleverantörer. Komponenter som tillverkas är stötfångare, utfyllandsdetaljer och emballage. Under 2016–2017 har företaget genomgått en expansionsfas där ett flertal produktfamiljer introducerats i verksamheten. En produktfamilj tillverkas av en ny variant av materialet EPP kallad Porous expanderad polypropylene (PEPP); materialgranulatet har håligheter vilket efter formgjutning skapar luftfickor i den färdiga produkten. Luftfickorna bidrar till att produkten blir ljudisolerande. Ett problem som uppstått med det nya materialet är att vid formgjutning med vattenånga stannar mycket vatten kvar i produkternas luftfickor.

    Syftet med rapporten var att antingen identifiera ett sätt att förebygga vatteninnehållet i PEPP-produkter, eller skapa en lösning för att hantera problemet. Examensarbetet avgränsades till att endast behandla tre PEPP-produkter; endast konceptuella lösningar skulle identifieras. Mål med examensarbetet var att framställa en kravspecifikation. DMAICmodellen valdes för att identifiera en lösning på problemet. En intervju med företagets kvalitetschef gjordes för att definiera problemet. Mätningar av produkternas vikt gjordes för att identifiera mängden vatten som stannar kvar i PEPP-produkterna. En intervju med representant från råvarutillverkaren JSP Arpro genomfördes för att analysera problemet och identifiera möjliga lösningar. Torkningstiden mättes i en konvektionsugn i en temperatur på 80 grader Celsius. En strukturerad produktionsutvecklingsprocess användes för att identifiera en lösning som hanterar problemet. Företagets nuläge och de tre utvalda produkterna analyserades. Värde-och flödesanalyser genomfördes och en kravspecifikation upprättades. Därefter utfördes en konceptgenerering och konceptval. Det slutliga konceptet utvärderades med en process-FMEA och kostnader uppskattades. Viktiga resultat är att det krävs en behandling i 360 minuter i en konvektionsugn för att avdunsta vattnet i PEPPprodukter. Ingen gångbar förebyggande lösning kunde identifieras. Det slutliga konceptet är en konvektionsugn som är konstruerad för att kunna existera i fabrikens nuvarande layout, och har kapacitet att klara av full produktionstakt av PEPP-produkter. Potentiella effektiviseringar kan göras genom användning av andra torkningsmetoder såsom strålning.

  • 344.
    Vassen, Robert
    et al.
    IEF-1, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany.
    Cernuschi, Federico
    CESI RICERCA, Power Generation Systems Dep. Milano, Italy.
    Rizzi, Gabriele
    Turbocoating.
    Scrivani, Andrea
    Turbocoating.
    Markocsan, Nicolaie
    University West, Department of Engineering Science, Division of Production Engineering.
    Östergren, Lars
    Surface Technology, Volvo Aero Corporation, Trollhättan, Sweden.
    Kloosterman, Arjen
    National Aerospace Laboratory NLR, Gas Turbines & Structural Integrity Department, Amsterdam, The Netherlands.
    Meverel, Remy
    ONERA, Chatillon Cedex, France.
    Feist, Jörg
    Southside Thermal Sciences (STS) Ltd, London, United Kingdom.
    Nicholls, John
    Cranfield University, Cranfield, United Kingdom.
    Recent activities in the field of thermal barrier coatings including burner rig testing in the european union.2008In: Advanced Engineering Materials, ISSN 1438-1656, E-ISSN 1527-2648, Vol. 10, no 10, p. 907-921Article, review/survey (Other academic)
  • 345.
    Wang, Yueyue
    University West, Department of Engineering Science, Division of Production System.
    Theoretical experiment of GISSMO failure model for Advanced High Strength Steel2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    When developing an electric vehicle, it is essential to evaluate the deformation in and around the battery box for different crash scenarios, and it is necessary to develop a more advanced model that would take into account all the stress modes. Thanks to the excellent properties of Advanced High Strength Steel (AHSS) combine with high strength for more safety and weight reduction for less exhaust emission, AHSS is more and more commonly used in automobile industry. The material employed in this project is DOCOL 900M and it is a martensitic steel with yield strength higher than 700MPa.  The focus of the current work is to describe the experimental setup for the GISSMO model used in LS-DYNA. A number of experimental methods and theories have been reviewed. Different geometries of the test specimens under different stress triaxialities have been discussed. The study also compares the accuracy and robustness of each of the testing methods and setups. The effect of anisotropy of materials on the mechanical properties was studied. Some summaries about how to reduce errors in the experiment under the conditions of low costing and high efficiency have been discussed. According to the stress-strain response of ductile materials, the parameters of plasticity model can be calibrated. The material can be implemented in finite element software to calibrate the parameters of damage and the prediction of material failure can be achieved. The experiment and simulation are always good to be used together in the research.

  • 346.
    Wanner, Bertil
    University West, Department of Engineering Science, Division of Mechanical Engineering.
    Strategies for Reducing Vibrations during Milling of Thin-walled Components2012Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Factors such as environmental requirements and fuel efficiency have pushed aerospace industry to develop reduced-weight engine designs and thereby light-weight and thin-walled components. As component wall thickness gets thinner and the mechanical structures weaker, the structure becomes more sensitive for vibrations during milling operations. Demands on cost efficiency increase and new ways of improving milling operations must follow.

    Historically, there have been two “schools” explaining vibrations in milling. One states that the entry angle in which the cutting insert hits the work piece is of greater importance than the exit angle. The other states that the way the cutter leaves the work piece is of greater importance than the cutter entry. In an effort to shed some light over this issue, a substantial amount of experiments were conducted. Evaluations were carried out using different tools, different tool-to-workpiece offset positions, and varying workpiece wall overhang. The resultant force, the force components, and system vibrations have been analyzed.

    The first part of this work shows the differences in force behavior for three tool-to-workpiece geometries while varying the wall overhang of the workpiece. The second part studies the force behavior during the exit phase for five different tool-to-workpiece offset positions while the overhang is held constant. The workpiece alloy throughout this work is Inconel 718.

    As a result of the project a spread sheet milling stability prediction model is developed and presented. It is based on available research in chatter theory and predicts the stability for a given set of variable input parameters.

  • 347.
    Wanner, Bertil
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering.
    Eynian, Mahdi
    University West, Department of Engineering Science, Division of Mechanical Engineering. University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Beno, Tomas
    University West, Department of Engineering Science, Division of Mechanical Engineering.
    Pejryd, Lars
    University West, Department of Engineering Science, Division of Production Engineering.
    Cutter Exit Effects during Milling of Thin-walled Inconel 7182012In: Advanced Materials Research, ISSN 1022-6680, E-ISSN 1662-8985, Vol. 590, p. 297-308Article in journal (Refereed)
    Abstract [en]

    During milling of thin-walled components, chatter vibrations give rise to process issues. These include dimensional inaccuracy, damaged and scrap parts, and damaged cutting tools. This, in turn, leads to loss of production time with increasing cost as a consequence. This paper identifies the force profile during a single cut milling process. It focuses on the exit and post-exit behavior of the cut and discusses the process dynamics. The force profiles of various tool-to-workpiece positions are analyzed as regards the exit and post exit phases. A standard on-the-market cutter and a specially designed zero rake cutter are used in the investigation. Finally, a time-domain simulation of the force is performed and compared to the experimental results. The study concludes that a small change in exit angle may result in a considerable improvement in cutting behavior. In addition, the tool position should be chosen so that the cutter exits in the least flexible direction possible for the workpiece.

  • 348.
    Westerlund, Christian
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Benchmark study: Sill concepts for electric vehicles2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The market for electric vehicles is expanding and the car manufacturer want to store as much energy as possible in the car. However, if the battery cells in the vehicle are damaged there is a risk that the battery could start a fire or explode. To avoid that the battery cells are damaged during a crash scenario, it is important to minimize the intrusion in the body structure. At the same time the car manufacturers do not want to increase the weight or manufacturing cost of the car more than necessary. The purpose of this study is to perform a benchmark study which compares the crashworthiness of different sill concepts used by various automotive companies.

    The different sill concepts that are being benchmarked in this thesis are Tesla Model S, BMW I3, Mercedes S-Class and Volkswagen E-golf. To be able to compare the sill structures from these different cars, some modifications must be done to their original geometry. A standardized cross section is created and the material thickness is adjusted until all concepts has the same mass. When the geometries have been designed, a nonlinear finite element calculation is performed to evaluate the crashworthiness of each sill concept. The finite element analysis is based on the standardized load case: side pole impact. The result shows that the concept inspired by Tesla Model S has the best performance when considering intrusion. However, if the concept inspired by Tesla Model S does not get enough support from the floor structure, it will lose its ability to absorb energy after a certain amount of time. And therefore, the BMW I3 concept could be a good alternative to the Model S concept if it is not possible to provide this additional support.

  • 349.
    William, Omar
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Development of waste sorting system2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor’s thesis is a mechanical engineering project done in cooperation with Swedish Innovators. The aim of this project has been to develop and design a waste sorting system in order to enhance the waste sorting process.

    After the first meeting with the client, it was understood that the product needs to be developed in aspects like design and functionality to make it suited for marketing. A number of demands was also established, in order to ensure that the redesigned product will fulfil its purpose.

    The project started with a product definition process that included studying existing products, search for relevant articles and a survey research to gather customer needs and ideas. After defining the product and gathering all possible information regarding the subject, a number of customer requirements were gathered.

    A number of concepts were generated according to the customer requirements and four of them was chosen by the client and the student for further development. And in order to choose the best concept of the four, selection matrices were used.

    The result of the project was one concept that satisfied almost all the requirements. The concept contains three main parts: a frame, a drawer and a container. The concept fulfils almost all the established demands by the client like ergonomic design and easy to install and assemble. After assembling the concept, the user should have a product that contains seven parts: one frame, two drawers and four containers, and the product should enhance the process of waste sorting with its practicality and ergonomic design.

  • 350.
    Xin, Zhu
    University West, Department of Engineering Science, Division of Production System.
    Improvement of Automated Guided Vehicle's image recognition: Object detection and identification2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Automated Guided Vehicle(AGV) as a kind of material conveying equipment has been widely used in modern manufacturing systems. [1] It carries the goods between the workshop along the designated paths. The ability of localization and recognizing the environment around themselves is the essential technology. AGV navigation is developed from several technologies such as fuzzy theory, neural network and other intelligent technology. Among them, visual navigation is one of the newer navigations, because of its path laying is easy to maintain, can identify variety of road signs. Compared with traditional methods, this approach has a better flexibility and robustness, since it can recognition more than one path branch with high anti-jamming capability. Recognizing the environment from imagery can enhance safety and dependability of an AGV, make it move intelligently and brings broader prospect for it. University West has a Patrolbot which is an AGV robot with basic functions. The task is to enhance the ability of vision analysis, to make it become more practical and flexible. The project is going to add object detection, object recognition and object localization functions on the Patrolbot. This thesis project develops methods based on image recognition, deep learning, machine vision, Convolution Neural Network and related technologies. In this project Patrolbot is a platform to show the result, we can also use this kind of program on any other machines. This report generally describes methods of navigation, image segmentation and object recognition. After analyzing the different methods of image recognition, it is easy to find that Neural Network has more advantages for image recognition, it can reduce the parameters and shorting the training and analyzing time, therefore Convolution Neural Network was introduced detailly. After that, the way to achieve image recognition using convolution neural network was presented and in order to recognize several objects at the same time, an image segmentation was also presented here. On the other hand, to make this image recognition processes to be used widely, the ability of transfer learning becomes important. Therefore, the method of transfer learning is presented to achieve customized requirement.

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