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  • 251.
    Lycke, Liselott
    et al.
    University West, Department of Engineering Science.
    Tano, Ingrid
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Building Quality Culture in Higher Education2016In: Proceedings of the 19th QMOD-ICQSS Conference, International Conference on Quality and Service Sciences, September 21-23, pp. 939-952, Rome, Italy. / [ed] Su Mi Dahlgaard-Park, Dr. Prof., Lund University & Jens J. Dahlgaard, Dr. Prof,. Linkoping University, Lund: Lund University Library Press , 2016, p. 939-952Conference paper (Refereed)
    Abstract [en]

    Purpose - Describe an approach to build a quality culture within a Higher Education InstitutionMethodology/Approach Case study

    Findings - We show the result of the mapped processes of a Higher Education Institution; Management planning and control, Education, Research and Support, and describe how the mapping was performed, working in cross functional teams. Further on we discuss the result ofthe pilot and the plan for implementation.

    Originality/Value of paper - A process-oriented approach in a Higher education institutions, with its complexity, creates opportunities for successful quality assurance and control when having an integrated quality assurance system.

  • 252.
    Lyphout, Christophe
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    Nylén, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    Klement, Uta
    University West, Department of Engineering Science, Division of Production Engineering.
    Sattari, M.
    Characterization of adhesion strenght of HVOF sprayed IN718 coatings2009In: Proceedings of th 22nd Internationa Conference on Surface Modification technolgies - SMT22. Trollhättan, Sweden / [ed] T.S. Sudarshan & Per Nylen, VALAR Docs , 2009, p. 11-18Conference paper (Refereed)
    Abstract [en]

    The tensile adhesion strength of thermally sprayed coating is conventionally evaluated via the ASTM C633-69 standard. The maximum measurable adhesion is then limited by the adhesion strength of the polymer media. High velocity oxy-fuel (HVOF) spraying can exhibit very high bonding strength and thus it is essential to develop an alternative method to evaluate coating adhesion strength. In this work a Modified Tensile Adhesion Test (MTAT) is proposed replacing gluing with induction brazing. The method was evaluated for HVOF sprayed Inconel 718 coatings deposited on Inconel 718 substrates. The effect of induction brazing process and the characteristics of the braze-coating interface was given particular interest. The results indicate that the method is superior to the ASTM C633-69 for characterisation of adhesion of coatings with high bond strength.

  • 253.
    Lyphout, Christophe
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    Nylén, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    Manescu, A.
    Università Politecnica delle Marche, Ancona, Italy.
    Pirling, T.
    Laue-Langevin Institute (ILL), Grenoble, France.
    Erratum  Residual stresses distribution through thick HVOF sprayed inconel 718 coatings: (Journal of Thermal Spray Technology DOI: 10.1007/s11666-008-9242- 9)2011In: Journal of thermal spray technology (Print), ISSN 1059-9630, E-ISSN 1544-1016, Vol. 20, no 5, p. 1140-Article in journal (Refereed)
  • 254.
    Lyphout, Christophe
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    Nylén, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    Manescu, A
    Università Politecnica delle Marche, Ancona, Italy.
    Pirling, T.
    Laue-Langevin Institute (ILL), Grenoble, France.
    Residual stresses distribution through thick HVOF sprayed inconel 718 coatings2008In: Journal of thermal spray technology (Print), ISSN 1059-9630, E-ISSN 1544-1016, Vol. 17, no 5-6, p. 915-923Article in journal (Refereed)
  • 255.
    Lyphout, Christophe
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    Nylén, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    Wigren, J.
    Characterization of adhesion strenght and residual stresses of HVOF sprayed Inconel 718 for aerospace repair applications2007In: Thermal Spray 2007: Global Coating Solutions: Proceedings of the International Thermal Spray Conference, Springer , 2007, p. 588-593Conference paper (Other academic)
  • 256.
    Långström, Rebecca
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Miljöutredning som verktyg i hållbarhetsarbetet2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The study includes an environmental investigation at the company HMC in Västra Götaland with four centers located in different cities: Borås, Mölndal, Skövde and Uddevalla. HMC is a competence -and logistics center based on care providers' needs in the field of resources and includes various services to support the care chain. The business delivers, supplies and services all types of aids to the entire region. HMC is located under Regionservice, which in turn is part of the Västra Götalandregionen (VGR) and must therefore meet the goals and requirements that come from the top. The environmental study is a part of ensuring that HMC relates to VGR and Regionservice's new environmental plan 2017-2020. The purpose of the study is to investigate which HMC's significant environmental aspects are, and how they can / should be combined with VGR and Regionservice environmental plan for 20172020. In the beginning of the study, literature was studied related to the topic, such as environmental management systems and the impact they have on the corporation, what an environmental study is, and laws and requirements related to environmental issues. The study has been conducted using observations, surveys and interviews with employees at the various centers and data collected to quantify the environmental aspects. In total, 29 environmental aspects have been identified in the corporation and then valued using a routine template from Regionservice. At the evaluation, six environmental aspects were considered significant for the corporation, two of which were positive for HMC; conventional waste, aid, chemicals, transportation, procurement and purchasing and reuse of appliances. The study shows that HMC's corporation are well-connected with VGR and Regionservice new environmental plan for 2017-2020, the significant environmental aspects of the business can be linked to the goals set in the region. HMC should always strive to reduce its environmental impact starting with the significant environmental aspects, and to achieve all the goals, continuous improvements must be made throughout the business.

  • 257.
    Lützhöft, Margareta
    et al.
    Chalmers.
    Ljung, Margareta
    University West, Department of Social and Behavioural Studies, Division of Social Pedagogy and Sociology.
    Nodin, Karin
    University West.
    Funktionsbaserad bemanning : En förstudie 2008Report (Other academic)
  • 258.
    Mahade, Satyapal
    et al.
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Curry, Nicholas
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Björklund, Stefan
    University West, Department of Engineering Science, Division of Mechanical Engineering.
    Markocsan, Nicolaie
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Nylén, Per
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Vassen, Robert
    Forschungszentrum Julich, Inst Energy & Climate Res IEK 1, Julich, German.
    Functional performance of Gd2Zr2O7/YSZ multi-layered thermal barrier coatings deposited by suspension plasma spray2017In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 318, p. 208-216Article in journal (Refereed)
    Abstract [en]

    7-8 wt% yttria stabilized zirconia (YSZ) is the standard ceramic top coat material used in gasturbines to insulate the underlying metallic substrate. However, at higher temperatures(>1200 °C), phase stability and sintering becomes an issue for YSZ. At these temperatures,YSZ is also susceptible to CMAS (calcium magnesium alumino silicates) infiltration. New ceramic materials such as pyrochlores have thus been proposed due to their excellent properties such as lower thermal conductivity and better CMAS attack resistance compared to YSZ. However, pyrochlores have inferior thermo mechanical properties compared to YSZ.Therefore, double-layered TBCs with YSZ as the intermediate layer and pyrochlore as the top ceramic layer have been proposed. In this study, double layer TBC comprising gadoliniumzirconate (GZ)/YSZ and triple layer TBC (GZdense/GZ/YSZ) comprising relatively denser GZtop layer on GZ/YSZ were deposited by suspension plasma spray. Also, single layer 8YSZ TBC was suspension plasma sprayed to compare its functional performance with the multilayered TBCs. Cross sections and top surface morphology of as sprayed TBCs were analyzed by scanning electron microscopy (SEM). XRD analysis was done to identify phases formed in the top surface of as sprayed TBCs. Porosity measurements were made using water intrusionand image analysis methods. Thermal diffusivity of the as sprayed TBCs was measured using laser flash analysis and thermal conductivity of the TBCs was calculated. The multi-layered GZ/YSZ TBCs were shown to have lower thermal conductivity than the single layer YSZ. Theas sprayed TBCs were also subjected to thermal cyclic testing at 1300 ºC. The double and triple layer TBCs had a longer thermal cyclic life compared to YSZ. The failed samples were cold mounted and analyzed by SEM.

  • 259.
    Malki, Daniel
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Shade, Omran
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Augmented Instructions: A study of methods for utilising 3D models in technical instructions2018Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis intends to identify and evaluate appropriate methods for ABB Capacitors to utilise their 3D models instead of 2D representations, with the purpose of reducing costumer’s misconceptions of installation manuals. ABB spends a significant amount of time designing detailed 3D models of their products. These are later converted into 2D representations of the models to create instructions with assembly drawings to their customers. 2D representations are less detailed than the 3D models and require prior experience to give an understanding of the products design. The customers don’t always possess the required experience to install capacitor solutions accordingly, this leads to wrong installations and increased lead-time. Three new visualisation methods were identified and evaluated on behalf of ABB Capacitors requirements and prerequisites. The three methods that were identified are Video recordings, Static-rotatable-3D Model and 3D sequence video. Next step was to identify and evaluate appropriate methods to present the 3D instructions. Initially two methods were considered: Augmented Reality and Virtual Reality. During the testing phase another opportunity was discovered, animated videos with camera views. The conclusion is that ABB Capacitors should replace the current instructions with animated videos with camera views and Augmented Reality experiences. Both suggested methods were demonstrated and evaluated for ABB Capacitors.

  • 260.
    Malmsköld, Lennart
    et al.
    Chalmers University of Technology.
    Örtengren, Roland
    Chalmers University of Technology.
    Carlson, Blair E.
    SAAB Automobile, Sweden.
    Nylén, Per
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Instructor based training versus computer based training: a comparative study2007In: Journal of Educational Technology Systems, ISSN 0047-2395, E-ISSN 1541-3810, Vol. 35, no 4, p. 457-478Article in journal (Refereed)
    Abstract [en]

    This article describes two studies conducted to compare assembly performance and learning rate between computer based training and traditional training of skilled assembly operators. The studies were performed with pre-series production parts from a car cockpit and they were integrated as part of the overall training activities during a new vehicle product launch. The computer based training tool used was a desktop based commercial VR tool with focus on cognitive interactive procedural learning. Both studies indicate that computer based training can replace instructor based training for this level of assembly complexity and that it has a positive effect in preparing skilled operators

  • 261.
    Malmsköld, Lennart
    et al.
    University West, Department of Engineering Science, Division of Automation Systems. Volvo Technology.
    Örtengren, Roland
    Chalmers University of Technology, Department of Product and Production Development,.
    Svensson, Lars
    University West, Department of Economics and IT, Divison of Informatics.
    Improved Quality Output through Computer-Based Training: An Automotive Assembly Field Study2015In: Human Factors and Ergonomics in Manufacturing, ISSN 1090-8471, E-ISSN 1520-6564, Vol. 25, no 3, p. 304-318Article in journal (Refereed)
    Abstract [en]

    In this article, two field experiments, conducted in an automotive assembly plant, evaluate how computer-based training of operational sequences and related quality information can support the assembly performance of the operators. The experiments were performed during the launch of a new vehicle. A comparison was made of learning progress and quality performance between a reference group of operators that only had regular training and a test group for which some of the regular training was replaced with individual computer-based training. Both quantitative measures of the quality output and questionnaires and observations were used to evaluate the effects of computer-based training. The results show a clear positive difference in learning progress and improvements in quality output for the test group compared with the reference group. This combined with positive attitudes expressed by the operators and their team leaders shows that this type of training is an effective way to train operators during launches of new vehicles in automotive production. © 2014 Wiley Periodicals, Inc.

  • 262.
    Malmsköld, Lennart
    et al.
    Volvo Technology.
    Örtengren, Roland
    Chalmers tekniska högskola.
    Svensson, Lars
    University West, Department of Economics and IT, Divison of Informatics.
    Training Virtually Virtual2012In: International Journal of Advanced Corporate Learning, ISSN 1867-5565, E-ISSN 1867-5565, Vol. 5, no 3, p. 29-36Article in journal (Refereed)
    Abstract [en]

    This paper reports from a longitudinal study of a Swedish manufacturer in the automotive industry, where a series of studies have explored the potential and limitations of computer-based training of assembly operators. The study is focusing on two supplementing sets of target variables – operators' attitudes and the quality output from operators in real production. Starting with small-scale studies where proof-of-concept for virtual training is established, the research moves on to comparative studies where different computer-based learning models are contrasted and evaluated. The research design ends with large-scale field experiments assessing the effects of computer-based training in terms of quality output. The results clearly demonstrate that computer-based training, when integrated with training of standardized work procedures, outperforms traditional methods for operator training, regardless of the content and the context of the assembly operation. The findings of the study are synthesized into a design framework for virtual training where cognitive and craftsmanship training is contrasted to the learning of product, process, sequence and finesse of assembly.

  • 263.
    Markocsan, Nicolaie
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    Nylen, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    Wigren, J.
    Volvo Aero Corporation, Trollhättan, Sweden.
    Xin-Hai, Li
    Siemens Industri Turbomachinery AB, Finspång, Sweden.
    Tricoire, A.
    Volvo Aero Corporation, Trollhättan, Sweden.
    Klement, Uta
    Chalmers University.
    Yao, Y.
    Chalmers University.
    Effect of Heat Treatment on Low Conductive Thermal Barrier Coatings2009In: Surface Modification Technologies XXII: Proceedings of the Twenty Second International Conference on Surface Modification Technologies Held at University West, Trollhättan, Sweden September 22-24, 2008 / [ed] T.S. Sudarshan & Per Nylen, VALAR Docs , 2009, p. 139-147Conference paper (Refereed)
  • 264.
    Markocsan, Nicolaie
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    Nylén, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    Wigren, J.
    Volvo Aero Corporation, Trollhättan.
    Li, X. H.
    Siemens Industrial Turbomachinery AB, Finspång.
    Tricoire, A.
    Volvo Aero Corporation, Trollhättan.
    Effect of thermal aging on microstructure and functional properties of zirconia-base thermal barrier coatings2009In: Journal of Thermal Spray Technology, Vol. 18, no 2, p. 201-208Article in journal (Refereed)
    Abstract [en]

    .

  • 265.
    Matsfelt, Johanna
    University West, Department of Engineering Science, Division of Mechanical Engineering.
    Study on the influence of the electrode tilt angle in GTAW doing CFD simulation of the heat source2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 266.
    Mazidi, Aimal
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Comparison of a new, high precision, energy efficient welding method with the conventional Gas Metal Arc Welding on high carbon steel base metal2014Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    CMT+P welding is less susceptible to hot cracking than the MAG welding process due to use of low heat input properties. Solidification cracking was found in all weld specimens that had greater 0.39KJ/mm heat inputs. Cracking occurs because of the contraction stresses generates during cooling. Hydrogen cracking is found in HAZ with low heat input parameters, this type of cracking occurred because of very rapid cooling and therefore not enough time to allow the hydrogen to dissipate from the specimen. To eliminate this type of cracking the experiment could be repeated by adding heating during welding to control and reduce the cooling rate. Due to high carbon content in the steel and very fast cooling the microstructure of the weld is martensitic in the base metal as well as the HAZ. Microstructure in the weld and base metal is martensitic due to high carbon con-tent and rapid cooling. At low heat inputs dilution is less and therefore lower carbon content in weld pool. Better weld appearance and weld quality is achieved with CMT+P welding process than the conventional GMA welding processes because of the new wire movement technology during welding

  • 267.
    Mehmood, Faisal
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Laser Welding of Aluminium in Automotive Industry2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    With all the advantages aluminium (Al) carries being the light weight and sustainable material, the laser welding of Al is tricky and complicated. The major challenges in laser welding of Al are the hot cracking, porosity and reflectivity. The experiments are done in order to understand the laser welding of Al process and analyse the process parameters impacts. In this thesis work, laser welding of Aluminium alloy is done in order to understand the process parameters effects on the weld quality. Experiments are done on the 5754-H22 and 6082-T6 alloys. Welding speed and laser power is kept constant for the experiments, however, laser focus position is varied on the plates. Focus position is kept on the surface of the plate as well as above and below the surface. The butt welding of same material alloy is done on the 3 mm plates. It is been analyzed that Al alloy 6082-T6 is easier to weld and give better weld quality as compared to 5754-H22. The overlap weld is done on 1.5 mm thick plates with CW (continuous wave) welding and PW (pulse weld). The laser welding is done with high speed, therefore, CW welding shows quality weld with no significant undercut or concavity as compared to PW welding method. The focus position above the surface shows quality weld in overlap weld with both PW and CW welding methods.

  • 268.
    Molina Griggs, Alejandro José
    University West, Department of Engineering Science, Division of Welding Technology.
    Laser Metal Powder Deposition of Austenitic Stainless Steel on Spheroidal Graphite Cast Iron: A corrosion resistant coating for the Food & Beverage Industry2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Spheroidal graphite cast iron is a material widely used in the industry for the manufacturing of all kind of covers and protective casings thanks to its good combination of mechanical properties, processability and cost. When cast iron components are put into service in corrosive environments the most common approach to protect the components is painting them. The protective painting has been found to flake off with time when aggressive washing procedures, such as the ones used in the Food & Beverage industry, are applied several times.

    In this project, the coating of cast iron with a corrosion resistant AISI 316L stainless steel by Laser Metal Powder Deposition has been studied as an alternative protection against corrosion. Several samples with different combinations of substrate preparation, number of layers and surface conditions were produced and analysed by optical microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, wash down tests and salt spray chamber corrosion tests.

    Main results show that the diffusion of carbon from the carbon-rich cast iron to the stainless steel coating, which would have a negative effect on the corrosion resistant properties, was significantly low as a result of the low penetration and dilution achieved during the laser metal powder deposition process. The deposited stainless steel coatings successfully protected the substrate during the corrosion tests and the integrity of the coatings is not expected to fail during the washing producers applied in the industry.

  • 269.
    Molldén, Mikael
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Kartläggning av projektet: ”Nyckelfritt” i Uddevalla kommun2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this report, the purpose has been to examine how a project has worked. This includes collecting data from various documents and interviews with people involved in the project, but also by observations of how the project team have been working in the project. In this report, there is a theory section in which a literature study was conducted by looking into contemporary research. The data chapter consists of interviews with 21 different participants, consisting of people working with the project, but also outside the project like people in other municipalities with similar tasks, and people in the municipality who will be affected by the project. The goal has therefore been to map out how the work has been carried out in the project, and to identify possible problems to see what can be improved for future projects, but also how to proceed with this project. In this thesis, the project group's work has been compared with a project model presented in the theory section. The reason why its compared to the project model is to provide a structure to identify how they worked with different parts of the project. This provided a complete overview of the project and a base for identifying improvement opportunities for the project. Improvements include to develop a project model to work and communication must be improved from the lead and down the line (top-down). The competence must also be evaluated before the project starts to see if additional training is needed to avoid delays in the project. Finally, project content and initiatives must be prioritized to ensure good planning and that the project manager is allocated in accordance with time required so this person will be best utilized for the project.   Date

  • 270. Murgau, A.
    et al.
    Pejryd, Lars
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    A Scientific Perspective on Improvement of Transactional Processes2006In: 39th CIRP International Seminar on Manufacturing Systems : the morphology of innovative maufacturing systems: Ljubljana, June 7-9, 2006, p. 473-478Conference paper (Other academic)
  • 271.
    Nia, Nima K.
    et al.
    Volvo Cars, VCIT, Olofström, Sweden.
    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 faster collision detection method applied on a sheet metal press line2011In: The 4th International Swedish Production Symposium, Lund: Swedish Production Academy , 2011, p. 467-472Conference paper (Refereed)
    Abstract [en]

    Geometrical collision detection is a time and resource consuming simulation task. In order to decrease time and resources, a general method applicable for 2D motions has been developed. The method is useful in simulation cases where 3D CAD data is part of an iterative method, e.g. optimization. The method is based on a transformation of a general 3D problem to a 2D problem, eliminating the need of 3D CAD models. Press Line simulations during the last decade have been accepted as a quality improvement method. Today simulations of automated press lines are done for internal collision checks in dies and external collision checks against dies and material handling equipment. If these collisions are not detected in simulations, they result in delays, in introduction of a new product in the line, so called line tryout or later when the line is ramped up to decide rate. The results of these collisions are used for pre-die design, design of grippers, maintenance and production planning. In this paper a new method, based on 2D simplifications, is developed and tested successfully in a virtual model of a press line at Volvo Car Manufacturing. Die Uppers 2 917 708 triangles and Die Lowers 602 686 triangles where reduced to 58 and 90 points. The result of the method shows substantial reduction of geometry data and considerable improvement in collision detection evaluation time over general 3D algorithms in the tested case.

  • 272.
    Nilsen, Morgan
    et al.
    University West, Department of Engineering Science, Division of Production System.
    Sikström, Fredrik
    University West, Department of Engineering Science, Division of Production System.
    Christiansson, Anna-Karin
    University West, Department of Engineering Science, Division of Production System.
    Ancona, Antonio
    University West, Department of Engineering Science, Division of Production System.
    In-process Monitoring and Control of Robotized Laser Beam Welding of Closed Square Butt Joints2018In: Procedia Manufacturing, E-ISSN 2351-9789, Vol. 25, p. 511-516Article in journal (Other academic)
    Abstract [en]

    In robotized laser welding of technical zero gap closed square butt joints it is critical to position the laser beam correct with regardsto the joint. Welding with an offset from the joint may cause lack of sidewall fusion, a serious defect that is hard to detect and gives a weak weld . When using machined parts with gap and misalignment between the parts that is close to zero, existing joint tracking systems will probably fail to track the joint. A camera based system using LED illumination and matching optical filters is proposed in this paper to address this issue. A high dynamic range CMOS camera and the LED illumination is integrated into the laser tool. The camera captures images of the area in front of the melt pool where the joint is visible and an algorithm based on the Hough transform and a Kalman filter estimates the offset between the laser spot and the joint position. Welding experiments, using a 6 kW fiber laser, have been conducted to evaluate the performance of the system. Promising results are obtained that can be used in the further development of a closed loop controlled joint tracking system.

  • 273.
    Nilsson, Emmy
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Andreasson, Gwendelines
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Åtgärdsförslag till Sansera Sweden AB för att uppfylla kraven i kvalitetsstandarderna ISO 9001:2015 och IATF 16949:20162017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this thesis, a Gap Analysis has been performed to find out how Sansera's quality management system meets the new requirements in the standards ISO 9001:2015 and IATF 16949:2016. The aim of the thesis is to make suggestions for actions that Sansera needs to take in their current quality management system in order to be certified according to the latest standards. In the Gap Analysis that was established, the standards ISO 9001:2015 and IATF 16949:2016 were compared to the previous standard ISO/TS 16949:2009 to find out what requirements are new. The requirements were then compared with Sansera's quality management system to identify the company's current situation. Based on the results of the Gap Analysis, the extent of the gaps was identified in Sansera's quality management system. In the study a benchmarking was performed against a company with similar processes like Sansera. The benchmarking was performed to verify if the methodology in this study is appropriate for its aim. The result of the benchmarking confirmed that the methodology used in the study is appropriate. Several of the requirements in the standards ISO 9001:2015 and IATF 16949:2016 requires that there should be documented information for the process that the requirement covers. The result of the Gap Analysis showed that a recurring reason for several of the gaps was that Sansera did not have the documented information for its processes required by ISO 9001:2015 and IATF:2016. Requirement 4.2.2 proved to be the most critical requirement because it can only be fulfilled if all other requirements containing requirements for documented information are fulfilled. In the study the suggestions for actions are presented to the gaps in Sansera's quality management system which is fulfilled by half, small part or not at all. The suggestions for actions are considered to be able to close the gaps in Sansera's quality management system. In order for Sansera to fulfill the gap regarding the lack of documented information, the company is recommended to update their current document management system, it is assumed to facilitate the introduction of the suggested procedures regarding documented information.   

  • 274. Nilsson, Patric
    et al.
    Appelgren, Anders
    University West, School of Business, Economics and IT, Division of Computer Science and Informatics.
    Henrikson, Per
    Volvo Aero.
    Runnemalm, Anna
    University West, Department of Engineering Science, Division of Process and Product Development.
    Automatic Ultrasonic testing for Metal Deposition2012In: Proceedings 18th World Conference on Non-Destructive Testing: 16 - 20 April 2012, Durban, South Africa, Durban, 2012, p. 1-10Conference paper (Refereed)
    Abstract [en]

    Metal Deposition (MD) is a method to build three dimensional metal geometries by welding using filler wire or powdered metal. NDT of a MD feature is required when the feature is located in an area of high stress or could be a potential hazard to the part. Ultrasonic testing (UT) can be used to detect pores, linear indications and lack of fusion in welds. This method has limitations when it comes to large parts with complex geometries with various shapes and sizes. A flexible method for inspecting complex geometries is to mount an ultrasonic water flow probe (squirter) on a robot. The robot can then follow a pre-programmed path to achieve full inspection of the feature. This paper shows results and functionality from a system where a squirter probe was used together with a standard industrial robot. Results from a scanning of a three-dimensional MD-structure are also presented.

  • 275.
    Nilsson, Per
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Konstruktion av lyfthjälpmedel till hydraulcylinder2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Among other products, JOAB Försäljnings AB manufactures hook lifts for trucks. The hook lifts are equipped with two hydraulic cylinders. These are lifted into place using round slings and chain hoists. This is not the optimal way of doing it. The reason for this is that the round sling can be incorrectly applied to the cylinder. In a worst-case scenario, the cylinder can be dropped with personal injuries and material damages as a result. The round sling may also cause damage to the cylinder paint through contact which is not desirable.  Thus, the goal of this project is to construct a lifting aid which lifts the cylinder into place in a safe way without damaging their paint. It must also meet Swedish work environment authority (Arbetsmiljöverkets) requirement for CE-marking.  To ensure that the workers will perceive it as helpful in their work, interviews and observations were done to identify their functional demands.  All demands are compiled and the concepts that meet them in various way are sketched. The best suited concept to proceed with was chosen by means of different concept selection methods. At this stage, the workers were also invited to ensure that the right concept was chosen.   Based on the chosen concept, a 3d model was developed. Relevant forces acting on the structure were identified and used in the strength calculations performed. The model was modified until a suitable balance between dimensions, material and strength was achieved. The final result is a lifting aid that will solve JOAB’s assembly problems.

  • 276.
    Nourozi, Benjamin
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Ogemark, Freddie
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Undersökning av SafetyEYE för interaktion mellan människa och robot i ett mindre riskområde2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis examined if SafetyEYE is safe and reliable for human-robot interaction in a smaller area of risk. In today's industry sought flexible solutions to make the robot safe as this is now done by having a solid barrier around the robot, which prevents the flexibility of human-robot interaction. To eliminate the need of a solid barrier there is a system named SafetyEYE.

    SafetyEYE is a camera system that enables three-dimensional zone monitoring where neither human nor robot must be in the zones while the robot is operating in automatic mode.

    The purpose of this study is to examine the system's resolution, sensitivity and sensitivity to reflections in a smaller risk area of 3.8 m x 2.8 m, as the system proved to be over sensitive to reflections from reflective objects in a greater risk area in a previous work. Some other purpose of this study is to examine what the ISO standards say on the application of a system like SafetyEYE and acquire knowledge about other methods and safety systems that enable a safe HRI (Human-Robot Interaction).

    The aim of this study is to examine if SafetyEYE is safe and reliable for monitoring a smaller risk area.

    The results of dissolution experiments showed that the system can detect objects down to 2 mm in width at a distance of 3.05 meters from the camera and with an illuminance of 315 lux in the experiment area. Furthermore, the results of the sensitivity experiments showed that the system was over-sensitive when the illuminance was 15 lux and 4000 lux in the experiment area. Regarding the result of reflection experiments showed that the system was reflection sensitive when two lamps with an illuminance of 4000 lux were directed against a reflective metal and a mobile. Four ISO standards found that covered the area of application of SafetyEYE. These ISO standards covering subareas: Stop function, requirements for an HRI area, the level of performance and safety distance. Furthermore, the results of the literature review of methods and safety systems for enabling a safe HRI showed that there are similar systems like SafetyEYE.

    Conclusions were that the system is not reliable in terms of light and reflection sensitivity when used for monitoring a smaller risk area, but can be used in a work environment that is adapted to the system, such as the illuminance does not change and the floor does not reflect. After the study of the ISO standards could be concluded that it is possible to implement SafetyEYE in a robot cell according to ISO requirements.

  • 277.
    Nyberg, Oscar
    University West, Department of Engineering Science, Divison of Natural Sciences, Surveying and Mechanical Engineering.
    Manufacturing steel tube car seat frames: Description of the product requirements and process methods2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The goal of this thesis work has been to describe the product requirements and process methods for manufacturing steel tube car seat frames. A wire frame is commonly used in the seat padding in the back seat of a car. The wire frame currently consist of wires with dimensions 4.5 mm and 6 mm. The frame is responsible for:

     Fastening the seat in the back seat of the car (keep it in place during e.g. impact),

     Serving as a point of attachment for upholstery,

     Keeping the shape of the moulded goods

    The main goal of the report was to present a viable solution based on the following objectives:

    1. Find a standardized tube, which corresponds to the current frame and meets all the stated requirements in the problems description,

    2. Define the minimum bend radius of the intended tube dimensions,

    3. Investigate suitable method of joining the tube parts while maintaining the strength of the frame

    A viable solution is presented, consisting of two tubes with customized dimensions:

     6 mm OD x 0.5 mm wall thickness will replace the 4.5 mm wire,

     7 mm OD x 0.75 mm wall thickness will replace the 6 mm wire

    This solution results in a weight reduction of 47 %, fulfilling the requirement stating that: 'The weight of the new frame should be approximately 50 % of the current frame weight'.

    The solution presented is 27 % more expensive, but the increased cost could be financed by the automotive industry's willingness to pay for reduced weight.

    The tubes have a theoretical minimum bend radius of 3 x the outer diameter of the two tube dimensions respectively.

    The tubes will be welded using projection resistance welding. This method is currently used welding the wire frame. The current machinery will be adjusted to work with the defined tube dimensions.

  • 278.
    Nylén, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    Applications of thermal spray technology for aerospace and automotive industry2013In: Heat Treatment and Surface Engineering - Proceedings of Heat Treatment and Surface Engineering, HTSE 20132013: HT & SE 2013, 16 to 18 May 2013, Chennai Trade Centre, Chennai, India / [ed] Bakshi S.R.,Kamaraj M.,Mudali U.K.,Sudarshan T.S.,Raj B.,Murty B.S., ASM International, 2013, p. 65-68Conference paper (Refereed)
    Abstract [en]

    Thermal spraying can provide thick coatings (approx. thickness range is 20 micrometers to several mm, depending on the process and feedstock), over a large area at high deposition rate as compared to other coating processes such as electroplating, physical and chemical vapour deposition. Coating materials available for thermal spraying include metals, alloys, ceramics, ptastics and composites Thermal spraying provides engineered coating solutions for a wide range of industrial applications. The aerospace industry was one of the first to exploit the benefits of thermal spray coatings. Nowadays, thermal spray technology is used in a large number of applications within this industry meeting high performance and quality requirements. Examples of applications within the aerospace sector are landing gears, abrasion wear resistant coatings, engines (combustion liners, discharge nozzles, blades, and compressor casings), and wing structures. An emerging application area for thermal spraying is the automotive area. Examples of applications within this area are synchronisation rings, piston rings, cylinder heads, turbocharger abradables, brake discs, cylinder bores, and hard chrom replacement This talk discusses some thermal spray applications within the aerospace and automotive sectors.

  • 279.
    Nylén, Per
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    Östergren, Lars
    Relationships between Process Parameters, Microstructure and Adhesion Strength of HVOF Sprayed IN718 Coating2010In: Proceedings of the 2010 International Thermal Spray Conference,: Singapore 3-5 May, 2010 / [ed] Basil R. Marple, Arvind Agarwal, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain Montavon, 2010, p. 1-7Conference paper (Refereed)
    Abstract [en]

    Fundamental understanding of relationships between process parameters, particle in-flight characteristics, and adhesion strength of HVOF sprayed coatings is important to achieve the high coating adhesion that is needed in aeronautic repair applications. In this study, statistical Design of Experiments (DoE) was used to identify the most important process parameters that influence adhesion strength of IN718 coatings sprayed on IN718 substrates. Special attention was given to the parameters combustion ratio, total gas mass flow, stand-off distance and external cooling, since these parameters were assumed to have a significant influence on particle temperature and velocity. Relationships between these parameters and coating microstructure were evaluated to fundamentally understand the relationships between process parameters and adhesion strength.

  • 280.
    Olofsson, André
    et al.
    University West, Department of Engineering Science, Divison of Natural Sciences, Surveying and Mechanical Engineering.
    Jaconelli, Linus
    University West, Department of Engineering Science, Divison of Natural Sciences, Surveying and Mechanical Engineering.
    Dimensionering av representativa riggdetaljer för motorkonfiguration2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis work describes concept development of parts for flight engine component testing. The developed parts purpose is to join the test object to the rig structure. The work has been performed at GKN Aerospace Sweden, Trollhättan.

    In the development process of aerospace components it is required to verify that the parts withstand the exerted loads. To accomplish this, a rig structure could be constructed to recreate the worst load case which the parts will be exerted to. To ensure that the rig is representative the parts joining the test object and the rig structure have to be designed to represent the flight engine components.

    The goal was to develop design models that transfer forces and thereby deformations to the test object within a margin of error by 5 percent. This was performed by comparing the flight engine components properties with the concepts.

    A number of concepts were evaluated from which the finals were optimized to fulfil the goal

  • 281.
    Olsson, Christian
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    The automatic manufacturing processes: the technique of controlling a mobile robot2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In today's industry it is of mayor concern to keep the manufacturing processes as effective and flexible as possible. The usage of robots and automatic technology is a much known way to achieve the goals of rationalization. The disadvantage lays in the fact that implementation of robots is usually a very resource consuming task. However, in some circumstances a solution to this matter may be to simply implement mobile robots instead of fixed robots.

    The task of this project is to successfully control and understand the system of a mobile robot in a automatic manufacturing process.

  • 282.
    Olsson, David
    University West, Department of Engineering Science, Division of Automation Systems.
    Effektivisering av tillverkningsprocess med avseende på materialflöden2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta examensarbete har utförts på Uddevalla Finmekanik AB (UFAB), Uddevalla, och är inriktat mot att effektivisera tillverkningsprocessen av ett kontrollskåp med avseende på materialflöden. Huvudproblemet är att tillverkningsprocessen inte följer företagets övriga interna flöden. Syftet med rapporten var att framställa en nulägesanalys över materialflödet för att fastställa vilka komplikationer som uppstår, och var, samt generera förbättringsförslag som skall motverka problemen.

    För att genomföra arbetet på ett grundligt sätt användes flera olika metoder och förbättrings-verktyg. Data samlades in genom att utföra observationer och intervjuer med anställda i flö-dets olika avsnitt. Genom att tillämpa förbättrings- och ledningsverktyg kunde data struktu-reras och analyseras. En flödeskarta skapades för att användas i arbetet med att identifiera förbättringsförslag. Ur nulägesanalysen framkom att problem i materialförsörjningen genom-syrar större delar av tillverkningsprocessen. Problemen sträckte sig från mindre, avdelnings-specifika problem till problem som är länkade mellan olika avdelningar. Det framgick att standardiserade arbetssätt och tydliga rutiner är betydande orsaker till varför flödet är inef-fektivt. För att ge ytterligare tyngd till arbetet genomfördes en benchmarking på VBG Truck Equipment i Vänersborg med syfte att lokalisera likartade problem och hur de hanteras.

    En optimering av processen kräver både kort- och långsiktigt förbättringsarbete från företa-get. Att engagera all delaktig personal i förbättringsaktiviteter är en förutsättning för ständiga förbättringar. Arbetet presenterar kortsiktiga förbättringsåtgärder såsom lagerstrukturering, tydligt fördelat ansvar och effektivare, interna transporter vilka skall motverka direkta pro-blem. Att utbilda personal både i hantering av företagets databassystem samt om anledningen till varför vissa moment måste utföras är långsiktiga förbättringar som är en förutsättning för att säkerställa effektiviteten i materialförsörjningen.

  • 283.
    Olsson, Ida
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Petersson, Josefine
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    3D Models with Product and Manufacturing Information: A step towards Model Based Engineering2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis work has been performed at GKN Aerospace Sweden AB.

    The objective was to initiate GKN Aerospace Engine System (GAES) work towards Model Based Engineering (MBE); letting the 3D models including Product and Manufacturing Information (PMI) replace the 2D drawings as the authoritative information source.

    To obtain the objective a pilot-study was performed. The pilot-study implied taking a 3D model including PMI through the downstream information flow at the company, to identify opportunities and challenges with this way of working.

    Requirements and aspects were identified to describe what need to be tested and answered during the pilot-study. Concurrent with the pilot-study the ranked list of requirements was followed-up and the identified aspects were answered. Out of 19 requirements the result showed that nine requirements are fully met with the current work approach, seven requirements are partly met and three requirements are not met. Since a major part of the requirements is fully met it will simplify GAES step in the direction towards MBE.

    The study showed that introducing MBE can imply both opportunities and challenges for GAES. One opportunity is that MBE can minimize errors when less human interpretation is needed. A challenge is that GAES way of working differs from other companies, which requires a new way of thinking and different functionality in software. There is today no solution for tracking changes in the 3D model including PMI, which needs to be solved before a transition.

    The employees believe that introducing MBE will lead to a big readjustment and that the cultural change at the company will be the biggest and most difficult challenge to overcome.

    Since the approach to work with MBE is still not as widespread within the aerospace industry, there are several aspects that need to be explored and studied further.

  • 284.
    Olsson, Jennie
    et al.
    University West, Department of Engineering Science.
    Simonsson, Lisa
    University West, Department of Engineering Science.
    Visualiseringsverktyg för produktionsplaneringav komplexa fabrikationer: ett konceptförslag för 30k-TEC-flödet på GKN AerospaceEngine Systems Sweden2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The thesis work has been situated at GKN Aerospace Engine Systems (former Volvo Aero)in Trollhättan and is defined to only deal with a specific detail. The detail is called 30k-TEC(Turbine Exhaust Case) and was developed during the years of 2011-2015 and will be handed over to the production during the first quarter of 2016. The yearly production volume will, within the coming five years, increase from approximately 250 to 800 details and is then estimated to account for about 20% of the revenue at GKN's site in Trollhättan. This is therefore to be considered as an important detail to the company.

    GKN consists of three workshops and the production of 30k-TEC runs through all of them.This makes it a complex matter to overview the production flow. The result of this is foremost an uneven production pace, wrong priorities and unmotivated workers. Because of these reasons a need to visualise the production flow on a screen in the workshops occurred.The information on the screen will be retrieved from GKN's Enterprise Resource Planningsystem and therefore a well thought out design and functions are required.

    The purpose of this work was to develop a concept of a visualisation tool that increases the possibility to overview the production flow, obtain information about the status of the production and also enable decisions of general planning regarding the production flow. The goal was to keep the visualisation simple and clear where information about the status of the production flow would be given within 30 seconds, regardless of if the person is familiar with the production flow or not.

    The process of generating the concepts occurred in consultations with the bosses of each workshop and the supervisors at GKN. The concepts were all in the range from just providing an overview to more detailed and the result finally became a combination. The difficulty of this project was to develop a simple but yet useful tool that was to be understood by all the employees. The result contained a visualisation of the production flow and how many details that was present in the different production stages, stock inventory, lead times, quality and delivery precision. Moreover, a specification to the IT-department was written to ease the programming of the tool.

    By the end of the work all the affected parties accepted the final concept since it fulfilled the requirements that was relevant in relation to the purpose of the work. Furthermore, programming and implementation is left to be done by GKN.

  • 285.
    Omicevic, Admir
    et al.
    University West, Department of Engineering Science.
    Elbing, Roger
    University West, Department of Engineering Science.
    Simulering av bultsvetsrobotar med IPS 2.0: För att utreda optimerings och balanseringsmöjlighet2010Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study has been performed on a stud weld station consisting of four stud weld robots from ABB which are used in the daily production at the body plant of Saab Automobile in Trollhättan. Currently, off-line programmed robot programs from IGRIP are used in several robot cells in the body plant. IGRIP has been used for several years without having any evaluation method for how the capacity has been used in the robot cells. The limitations of IGRIP are that it cannot automatically generate collision free paths, which is very time consuming. The input of the via-points is done manually by the programmer which results in less than maximum capacity in the robot cell. These problems have triggered Saab to investigate the potential for making capacity available by using a software under development, IPS 2.0. The software is developed by FCC and has optimization and balancing functions. It can also generate collision free paths for the robots in a robot cell. One optimized path and one reference path have been created in order to evaluate the time reduction in percent. It was shown that there was potential to free up capacity in the robot cell by using IPS 2.0.Date:

  • 286.
    Ottosson, Andreas
    University West, Department of Engineering Science, Division of Mechanical Engineering.
    Thermal spraying by HVAF as an environmentally friendly alternative to electrolytic hard chrome plating of piston rods2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 287.
    Ottosson, Hans
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Utveckling av miljövänligt elverk för personligt bruk2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Möjligheten att utveckla ett vattenkraftverk för personligt bruk har behandlats. Målet var att se om det gick att tillverka ett kraftverk som kan underhålla en avlägsen stuga med ström för att använda TV, dator, lampa och dylikt när den konventionella elen inte finns installerad. Ett koncept utvecklades med syfte att minimera miljöpåverkan. Detta koncept byggdes och begagnade delar användes vid tillverkningen. Anläggningen kunde också testas, vilket visade att tillfredställande resultat erhölls.

  • 288.
    Pejryd, Lars
    et al.
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Andersson, P.
    Information Back Bone Systems for Virtual Manufacturing, a Comparison of ERP and Engineering Based PLM Systems2006In: 39th CIRP International Seminar on Manufacturing Systems : the morphology of innovative maufacturing systems: Ljubljana, June 7-9, 2006, p. 405-410Conference paper (Other academic)
  • 289.
    Pejryd, Lars
    et al.
    Örebro University.
    Beno, Tomas
    University West, Department of Engineering Science, Division of Production Engineering.
    Carmignato, Simone
    University of Padova, I 35131 Padova, Italy .
    Computed Tomography as a Tool for Examining Surface Integrity in Drilled Holes in CFRP Composites2014In: Procedia CIRP, ISSN 2212-8271, Vol. 13, p. 43-48Article in journal (Refereed)
    Abstract [en]

    In light weight structures the joining of composite materials and of composites to metals are key technologies. A manufacturing method associated with joining is the drilling of holes. The hole creation in CRFP through drilling is associated with several defects related to the process, both on the entry and exit sides of the hole and also with dimensional and surface roughness issues of the hole wall. The detection of damage due to the process is not trivial. Especially interesting is non-destructive methods. In this work X-ray computed tomography is used to determine defects due to drilling of holes in a CFRP composite using twist drills with different geometrical features at different drilling parameters. The results can be used to establish relationship between different geometrical features of drills in combination with cutting parameters and resulting surface integrity of holes. © 2014 The Authors. Published by Elsevier B.V.

  • 290.
    Pejryd, Lars
    et al.
    University West, Department of Engineering Science, Research Enviroment Production Technology West.
    Eriksson, Rebecka
    Bofors Test Center,Karlskoga,.
    X-ray Computed Tomography as a Tool in Joining Process Development2014In: Proceedings of the 6th International Swedish Production Symposium 2014 / [ed] Stahre, Johan, Johansson, Björn & Björkman, Mats, 2014, p. 1-7Conference paper (Refereed)
    Abstract [en]

    3-D information on defects in joints are of great importance. Computed tomography is a method that holds the promise of generating this information. This work shows several examples of application of CT on joining or joining related processes. The detection of foreign material, cracks and porosity is shown as well as the ability to investigate much larger volumes than what is feasible with traditional cut-ups. Some limitations are also discussed.

  • 291.
    Persson, Tore
    et al.
    University West, Department of Technology.
    Ottermark, Kenth
    En kritisk analys av företagsnätverk2005Report (Other (popular science, discussion, etc.))
    Abstract [sv]

    Vi har studerat samarbetet i olika företagsgrupperingar inom Västra Götalands län. I studien har vi jämfört de aktuella grupperingarna med bl.a. beskrivningar av grupperingar i industriella distrikt i norra och mellersta Italien. Dessutom har jämförelser gjorts med det nätverkssamhälle, som Castells har beskrivit, samt det samhälle – det gamla agrarsamhället - som Tönnies och Colley studerat m. a. p. sociala relationer. *För det första har vi funnit att det tar lång tid, 5 – 10 år, att skapa ett fungerande nätverk. Alla grupperingar blir inte framgångsrika nätverk. De flesta grupperingar tycks faktiskt aldrig nå fram till ett fungerande nätverk och det är kanske inte heller alltid syftet. Så t.ex.var syftet i de LRF-grupperingar vi studerat främst att få stöd till utbildningsinsatser och för det var man i stort sett tvingad att bilda ett nätverk. Vi tycker oss se att det finns skillnader i arbetssätt mellan grupperingar, som har samarbetat inbördes under en längre tid (ca 5 år) och de som är relativt nystartade (1-2 år). Även attityderna tycks vara annorlunda. Eftersom det statistiska underlaget är begränsat kan vi inte uttala oss med säkerhet i dessa frågor. Vi har dock noterat att man i de studerade grupperingarna i allmänhet ägnar för kort tid åt att bygga nätverket. De tror att grupperingen skall fungera som ett bra verktyg utan närvaro av det sociala kapitalet. *Vi kan inte se tillstymmelse till det ”nätverkssamhälle”, som Castells har beskrivit. Möjligen finns det samhället representerat i vår region, men det har ännu inte kommit till de företag och de grupperingar som denna studie omfattar. Det är troligt att ”nätverkssamhället” finns mer påtagligt i företag, som ingår i globala koncerner. Däremot finns det tecken på att IT-kunnandet och användandet ökar starkt i företagen. *Inte heller passar Tönnies och Cooleys beskrivningar av samverkan och umgänge i agrarsamhället in på de företagsgrupperingar, som vi har studerat. Däremot kan vi se att deras beskrivningar delvis passar in på byalag och utvecklingsgrupper på landsbygden. Dessa grupperingar har ett högt värde på det sociala kapitalet och den sociala väven är relativt tät. Varje byalag är dock för litet för att kunna åstadkomma den utveckling som önskas. Med intensifierad samverkan mellan olika byalagsgrupperingarna inbördes och med andra grupperingar kan resultatet förväntas bli bättre. *När vi jämför de studerade grupperingarna med industriella distrikt ser vi att det sociala kapitalet hos dessa är mycket lägre än i de industriella distrikten. Det tar åtminstone 20-30 år att formas. Traditioner, normer och värderingar skall ha hunnit att bli en del av den lokala kulturen, dvs. de bör ha gått i arv mellan två generationer.

  • 292.
    Peterson, Olof
    University West, Department of Engineering Science, Divison of Natural Sciences, Surveying and Mechanical Engineering.
    Framtagning av process för hantering av verktyg för skärande bearbetning2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Examensarbetet har utförts på UFAB i Uddevalla och handlar om processen för hanteringen av verktyg vid bearbetning. Huvudproblemet utgörs av det höga antal skärverktyg i omlopp vilket är större än vad behovet kräver. Vidare saknas dokumenterad verktygsspecifikation. Syftet med rapporten var att framlägga två-tre processer och välja den mest kostnadseffektiva, jämfört med dagens hantering.

    För att lyckas med arbetet har följande fem metoder använts till att samla in nödvändig data och visualisera kvalitetsproblem samt lösningar: intervju, observation, processjämförelse, förbättrings-och ledningsverktyg. Intervjuerna genomfördes med anställda från inköpsavdelningen, godsmottagningen, operatörer i maskinverkstaden och produktionsteknikern för att få en helhetssyn över verktygsflödet. Totalt genomfördes nio intervjuer. Processjämförelsen utfördes hos VBG Truck Equipment i Vänersborg som har en omfattande bearbetning. Syftet med undersökningen var att identifiera nyckelfaktorer i de områden UFAB har svagheter. Förbättrings-och ledningsverktygen användes till att identifiera grundorsaker samt välja förbättringsförslag. Dataanalysen visade att dagens process har ett flertal kvalitetsproblem, bl.a. låg lagertillgänglighet i centrallagret, flertalet olika verktygsvarianter och leverantörer samt ett ostrukturerat lager. Vidare har verktygsofferter skickat till UFABs mest frekventa verktygsleverantörer för att reducera antal leverantörer. Examensarbetet har resulterat i förbättringsförslag vilka kan indelas i fortlöpande åtgärder och lösningsförslag. De fortlöpande åtgärderna består av fyra punkter vilka är följande: Produktionsteknikern ansvarar för inköp, sammanställ verktygslistor efter ABC-analys, färre antal leverantörer och varianter samt 5S på arbetsstationerna samt i lagret. Första lösningsförslaget är en förbättrad manuell hantering gentemot dagens hantering och andra lösningsförslaget är en lagerautomat. Slutvalet blev en kombination, av första och andra lösningen. Strukturera hyllfacken enligt förvaringsförslag ett och investera i ett elektroniskt lagerhållningssystem

  • 293.
    Quincoses, Annette
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Andersson, Malin
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Tidseffektivisering av inköpsprocessen på Mape Sweden AB2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This Bachelor's Thesis has been performed at Mape Sweden AB with the purpose of elimi-nate or reduce the non-value adding activities within the purchasing process. By examining the company's purchasing process for tools and spare parts, the goal is to find solutions that will entail time-efficiency in the purchasing process.

    The work in this thesis is of qualitative nature. This approach was chosen to obtain an un-derstanding of the current situation with qualitative methods. To collect data the group per-formed several observations and interviews, literature reviews and a benchmarking at a dif-ferent manufacturing company. To develop proposals for improvements to the company, a spaghetti diagram was conducted tracking all movements at goods-withdrawal and goods-receipt. A time study was conducted to compare the times before and after implementation of improvement proposals.

    The current situation analysis showed that purchases are made by different people resulting in that there is not a standardized approach. Spaghetti diagram of movements in goods-withdrawal and goods-receipt showed that there is numerous movements and some of them are unnecessary. Proposals for improvements was conducted based on the information from current situation analysis together with information obtained from benchmarking. The pro-posal for goods-withdrawal was that the workers themselves enter goods-withdrawal in the SAP-system. The proposals for goods-reception was to receive the goods once a day, place a shelf for non-stocked tools and a shelf for supplies in the tool shed as well as making demands on suppliers to always have the part number and stock location on the packing slip included with all deliveries.

    .When implementing the groups proposed improvements, the total time spent on goods-receiving and goods-withdrawal was reduced from 6 hours, 40 minutes and 23 seconds to 1 hour and 58 minutes, which represents a decrease of 70%.

    For future work the group recommend that the improvement proposals also be implemented on other types of purchases within the company and that the company further investigate the benefits of tool cabinet and scan-ning systems.

  • 294.
    Ramesh, Nithin
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    ROS based communication system for AGVs: A service oriented architecture (SOA) approach2016Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project first explored various methods of designing a communication and control system for an AGV. It then implemented a SOA based communication system in ROS on the selected AGV. The ROS package created in the project implemented functions of the Aria and ArNetworking libraries from Adept. The next step of the project implemented the functions of teleoperation, mapping and transfer of maps and navigation from Aria into ROS. The packages built implemented these functions in different ways to test the best method to transfer Aria functions into ROS. A generic set of rules were then formulated that aided the conversion of these functions for users unfamiliar with either of the two packages (ROS and Aria).

  • 295.
    Renugopal, Rajalakshmi
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Design, Analysis and Improvement ofCopper Indium Gallium Selenium ThinFilm Solar Arrays Using SCAPS-1D Simulation Software2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The simulation of high efficiency CIGS, i.e., Copper Indium Gallium Selenide cells is the main objective of this thesis. We used SCAPS software for creating a model and basic analysis of the solar cell configuration. An Efficiency calculation was performed by using a baseline model in the SCAPS1D-software. As a first step, a multi-layer absorber structure was added with a graded Ga concentration with varying absorber layer thickness. With this, the electric field increased internally, thus helping to increase the output voltage of the cell. As second and third steps, the temperature and the bandgap was varied. In the final simulation of the CIGS solar cell, an efficiency of 16.33 % could be achieved. A change in temperature from 300 K to 400 K resulted in a drop of efficiency, while a simulated variation in the bandgap and electron affinity resulted in a CIGS solar cell with an efficiency of 22.87 %.

  • 296.
    Repo, Jari
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Wretland, Anders
    GKN Aerospace Engine Systems AB, Trollhättan, Sweden.
    Beno, Tomas
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Tu, Juei-feng
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing. North Carolina State University, Department of Mechanical and Aerospace Engineering, Raleigh, North Carolina, United States.
    Detectability of various machining conditions by using internal encoder signals2016In: The 7th International Swedish Production Symposium, SPS16, Conference Proceedings: 25th – 27th of October 2016, Lund: Swedish Production Academy , 2016, p. 1-7Conference paper (Refereed)
    Abstract [en]

    Automated Tool Condition Monitoring (TCM) often relies on additional sensors sensitive to tool wear to achieve robust machining processes. The need of additional sensors could impede the implementation of tool monitoring systems in industry due to the cost and retrofitting difficulties. This paper has investigated the use of existing position encoder signals to monitor a special face turning process with constant feed per revolution and machining speed. A signal processing method by converting encoder signals into a complex-valued form and a new vibration signature extraction method based on phase function were developed to analyze the encoder signals in the frequency domain. The cumulative spectrum indicated that the spectral energy would shift from the lower to the higher frequency band with increasing cutting load. The embedded vibration signatures extracted from the encoder signals provided additional detectability of the machining condition with distinguishable spectral modes. This paper confirms the sensitivity of the encoder signals and more signatures could be extracted for tool wear detection in the future work.

  • 297.
    Riisggard, Anton
    et al.
    University West, Department of Engineering Science, Division of Production System.
    Eliasson, Per-Albin
    University West, Department of Engineering Science, Division of Production System.
    Mapping of camera-controlled front lighting systems for passenger cars2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    More and more carmakers equip their cars with lighting systems that adapt to different driving conditions. Recently, new systems have arrived on the market and it is important for ÅF Automotive & Vehicle in Trollhättan to acquire knowledge regarding several aspects of the European market. The main objective of the thesis is therefore to provide a general idea of various LED-array/matrix concepts available on this market. Other objectives comprise price-setting strategies, purchasing costs, brand awareness using signature headlights, legal requirements and customer experience. Several research questions have been defined in order to fulfil the thesis aims.

    The methodology leading up to the results is mostly based on literature studies but also comprises interviews, car dealer visits and test driving cars. LED-array/matrix systems are available on:

    •  Audi – Audi Matrix LED
    •  Mercedes-Benz: Multibeam
    •  Mazda – Adaptive LED Headlights
    •  BMW – BMW Adaptive LED
    •  Opel – Opel IntelliLux

    The systems are available on models in the C-, D-, E-, F-, S- and J-segments and are available as either standalone features, part of packages or included in the baseline equipment. Comparisons are made regarding the purchasing costs of identified systems. Signature headlights and design philosophy's, which different car makers use in order to create brand awareness have also been outlined. Furthermore, systems have been identified which yet are not fitted in specific cars. These systems are also described and in addition, the suppliers of these have been mapped. Valeo, Automotive Lighting, Koito, Varroc and ZKW have been identified. The legal requirements that need to be considered as limiting factors, as stated in ECE Vehicle Regulations No. 48 and 123, have also been identified and summarised. Finally, test driving results from two occasions are presented and analysed, featuring Mercedes-Benz A-class in the first and Mazda CX-5 in the second.

    The delivered results are discussed and several conclusions are drawn in this thesis, which hopefully sets a platform for this field of engineering and future work at ÅF.

  • 298.
    Rohdin, Patrik
    et al.
    Linköpings universitet.
    Johansson, M
    Saab Automobile AB.
    Löfberg, J
    Automatic Control, Linköping University, Sweden.
    Ottosson, Mattias
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Energy efficient process ventilation in paint shops in the car industry: Experiences and an evaluation of a full scale implementation at Saab Automobile in Sweden.2012In: Ventilation 2012, 2012, p. 1-6Conference paper (Refereed)
    Abstract [en]

    Support processes in industrial energy systems, such as heating, ventilation and cooling systems, are important processes in industrial premises as they are related to energy cost, product quality as well as the indoor environment.

    In the vehicle production process the paint shop is the most energy intensive part, and about 75% of the energy is used in the ovens and spray booths. The spray booth line, which includes paint application and the oven, uses large quantities of air in order to keep the air quality in an optimal range to achieve the desired paint quality. The approach used in paint shops has up to now been to keep as much of steady state conditions as possible to avoid paint defects due to disturbances in the balance. This means that these high air flows are used also at low and non production hours. There is thus a large potential to increase energy efficiency by controlling the air flow and heating without losing the critical balances. This paper will present an initial post-implementation evaluation of the energy efficiency potential and experiences after running this type of system. CFD has been used to investigate the control strategy.

  • 299.
    Roskvist, Jimmy
    et al.
    University West, Department of Engineering Science.
    Rydell, Richard
    University West, Department of Engineering Science.
    Konceptframtagning av inspektionspluggar till flygmotorer2009Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report describes the results of the project "Concept development of jet engine inspection plugs" carried out in the spring of 2008. The work was done at the department of product definition at the company Volvo Aero in Trollhättan. The objective of the work was to develop concepts for a "Volvo-unique" inspection plug. The work is part of Volvo Aero's focus on proprietary (self-developed) technologies. Inspection plugs can be found on virtually all aircraft engines and gas turbines. They are used during inspections with fiber optics done at regular intervals during engine operation. Since the inspection plugs are screwed in and out many times during the life of an engine, it is important that the handling (the assembly and disassembly) is simple. It is also very important that the plugs are properly fixed in position to prevent them from coming off during operation. The focus of the work was to develop proposals on how the assembly and fixing of plugs could be designed to simplify the handling and have adequate and simple function. The procedure during the work was to first study relevant theory and methods that could be used. Then development was carried out according to the first steps of the systematic design methods. These steps include product specifications, concept generation, evaluation and selection of concepts, and development of selected concept. During the implementation, a number of tools and methods, including QFD, FMEA and decision matrices were used. Out of 14 developed concepts, two were chosen for comparison with a leading rival. Both developed concepts turned out to outscore the competitor and the main difference was the cost of production. One of the concepts was considered to have advantages over the other and was consequently chosen for further development. Geometry, manufacturing, materials, sealing and misalignment were the focus areas of the development. CAD models were made of the various design ideas that were identified and one principal inspection plug was recommended for further development.

  • 300.
    Ru, Tao
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Spray Parameters Influence on Suspension Plasma Sprayed Zirconia coatings properties2014Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Thermal barrier coatings (TBCs) are a simple and proven method to protect hot section components. Suspension Plasma Spray (SPS), an emerging process technology to generate TBCs, compared with traditional Atmospheric Plasma Spray APS, can deposit thinner coat-ings with finer microstructure. Operating parameters play an important role in developing certain properties of coating. In this thesis work, power level, gas flow rate, number of spray-ing strokes, spray gun's nozzle size i.e. internal diameter and suspension rate were controlled to produce coatings with different microstructures and porosity levels. According to the ex-perimental results, the power level of plasma gun play an essential role on coating micro-structure, for instance, the density of vertical cracks increased with growing the power level. The number of spraying strokes showed also an impact on coating porosity. However, due to different nozzle sizes i.e. diameter, the same coating property were controlled by different operating parameters. For coatings deposited by small and large nozzles, their coating thick-ness and roughness mainly relied on power level and gas flow rate. In contrary, it seems that the coating roughness was not influenced by the same parameters when it was deposited by medium nozzle. Also, gas flow rate do not have as big as influence on coating thickness

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