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  • 151.
    Glorieux, Emile
    et al.
    University West, Department of Engineering Science, Division of Automation Systems.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Automation Systems.
    Svensson, Bo
    University West, Department of Engineering Science, Division of Automation Systems.
    Lennartson, Bengt
    University West, Department of Engineering Science, Division of Automation Systems. University West, Department of Engineering Science, Division of Production Systems. Chalmers University of Technology, Department of Signals and Systems, Gothenburg, Sweden.
    Constructive cooperative coevolutionary optimisation for interacting production stations2015In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 78, no 1-4, p. 673-688Article in journal (Refereed)
    Abstract [en]

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

  • 152.
    Glorieux, Emile
    et al.
    University West, Department of Engineering Science, Division of Automation Systems.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Automation Systems.
    Svensson, Bo
    University West, Department of Engineering Science, Division of Automation Systems.
    Lennartson, Bengt
    Chalmers University of Technology, Department of Signals and Systems.
    Optimisation of Interacting Production Stations using a Constructive Cooperative Coevolutionary Approach2014In: Proceedings of 2014 IEEE International Conference on Automation Science and Engineering (CASE), IEEE conference proceedings, 2014, p. 322-327Conference paper (Refereed)
    Abstract [en]

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

  • 153.
    Glorieux, Emile
    et al.
    University West, Department of Engineering Science, Division of Production Systems.
    Franciosa, Pasquale
    University of Warwick, Warwick Manufacturing Group, CV4 7AL Coventry, UK.
    Ceglarek, Darek
    Warwick Manufacturing Group, University of Warwick, CV4 7AL Coventry, UK.
    End-effector design optimisation and multi-robot motion planning for handling compliant parts2018In: Structural and multidisciplinary optimization (Print), ISSN 1615-147X, E-ISSN 1615-1488, Vol. 57, no 3, p. 1377-1390Article in journal (Refereed)
    Abstract [en]

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

  • 154.
    Glorieux, Emile
    et al.
    University West, Department of Engineering Science, Division of Automation Systems.
    Svensson, Bo
    University West, Department of Engineering Science, Division of Automation Systems.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Automation Systems.
    Lennartson, Bengt
    University West, Department of Engineering Science, Division of Automation Systems. University West, Department of Engineering Science, Division of Production Systems. Department of Signals and systems, Chalmers University of Technology.
    Improved Constructive Cooperative Coevolutionary Differential Evolution for Large-Scale Optimisation2016In: Computational Intelligence, 2015 IEEE Symposium Series on, IEEE, 2016, p. 1703-1710, article id 7376815Conference paper (Refereed)
    Abstract [en]

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

  • 155.
    Glorieux, Emile
    et al.
    University West, Department of Engineering Science, Division of Production Systems.
    Svensson, Bo
    University West, Department of Engineering Science, Division of Production Systems.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Production Systems.
    Lennartson, Bengt
    University West, Department of Engineering Science, Division of Production Systems. Department of Signals and Systems, Chalmers University of Technology,Gothenburg, Sweden.
    Multi-objective constructive cooperative coevolutionary optimization of robotic press-line tending2017In: Engineering optimization (Print), ISSN 0305-215X, E-ISSN 1029-0273, Vol. 49, no 10, p. 1685-1703Article in journal (Refereed)
    Abstract [en]

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

  • 156.
    Glorieux, Emile
    et al.
    University West, Department of Engineering Science, Division of Automation Systems.
    Svensson, Bo
    University West, Department of Engineering Science, Division of Automation Systems.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Lennartson, Bengt
    University West, Department of Engineering Science, Division of Manufacturing Processes. University West, Department of Engineering Science, Division of Production Systems. Chalmers.
    Optimised Control of Sheet Metal Press Lines2014In: Proceedings of the 6th International Swedish Production Symposium 2014 / [ed] Stahre, Johan, Johansson, Björn & Björkman, Mats, 2014, p. 1-9Conference paper (Refereed)
    Abstract [en]

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

  • 157.
    Goel, Sneha
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Hybrid powder-suspension plasma spraying for diverse function-dependent coating architectures2016Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

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

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

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

  • 158.
    Gokavarapu, Naga Sai Pavan Rahul
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Termisk cyklisk utmattning studie av Gd2Zr2O7 / YSZ flerskikts termiska barriärbeläggningar2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

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

  • 159.
    Gran,, Ludvig
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Utveckling av parameter för svetsprocessen Nyckelhål-TIG i titan-6Al-4V för tjocklek 7 mm2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

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

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

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

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

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

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

  • 160.
    Granlund, Erik
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Framtagning av koncept för tryckindikator och informationsöverföring för luftaxel2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

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

  • 161.
    Gråsjö, Urban
    University West, School of Business, Economics and IT, Division of Law, Politics and Economics. University West, School of Business, Economics and IT, Divison of Law, Economics, Statistics and Politics.
    Accessibility to R&D and Patent Production2005Report (Other academic)
    Abstract [en]

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

  • 162.
    Grönberg, Christoffer
    University West, Department of Engineering Science.
    Simulering och cykeltidsberäkning av automatiserad produktionslina med hjälp av Process Simulate2010Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

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

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

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

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

  • 163.
    Gudfinnsson, Kriseins
    et al.
    University of Skövde, School of Informatics,Skövde, Sweden.
    Rose, Jeremy
    University of Skövde, School of Informatics,Skövde, Sweden.
    Aggestam, Lena
    University West, School of Business, Economics and IT.
    Tackling lack of motivation in aspirational analytics companies: SME examples from the manufacturing industry2019In: International Journal of Business Intelligence Research, ISSN 1947-3591, E-ISSN 1947-3605, Vol. 10, no 1, p. 1-18Article in journal (Refereed)
    Abstract [en]

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

  • 164.
    Guevara-Garca, Alfredo
    et al.
    McMaster University, Department of Chemistry and Chemical Biology.
    Echegaray, Eleonora
    Pontificia Universidad Catlica de Chile, Facultad de Qumica, Laboratorio de Qumica Terica Computacional (QTC).
    Toro-Labbe, Alejandro
    Pontificia Universidad Catlica de Chile, Facultad de Qumica, Laboratorio de Qumica Terica Computacional (QTC).
    Jenkins, Samantha
    University West, School of Business, Economics and IT, Division of Computer Science and Informatics.
    Kirk, Steven R.
    University West, School of Business, Economics and IT, Division of Computer Science and Informatics.
    Ayers, Paul W.
    McMaster University, Department of Chemistry and Chemical Biology.
    Pointing the way to the products Comparison of the stress tensor and the second-derivative tensor of the electron density2011In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 134, no 23, p. 234106-Article in journal (Refereed)
    Abstract [en]

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

  • 165.
    Gunnarsson, Håkan
    et al.
    University West, Department of Engineering Science.
    Johansson, Filip
    University West, Department of Engineering Science.
    Framtagning av koncept för monteringsstation2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

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

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

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

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

  • 166.
    Gupta, Mohit Kumar
    et al.
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Dwivedi, Gopal
    Stony Brook University, USA.
    Nylén, Per
    University West, Department of Engineering Science, Research Environment Production Technology West.
    Vackel, Andrew
    Stony Brook University, USA.
    Sampath, Sanjay
    University West, Department of Engineering Science, Research Enviroment Production Technology West.
    An Experimental Study of Microstructure: Property Relationships in Thermal Barrier Coatings2013In: Journal of thermal spray technology (Print), ISSN 1059-9630, E-ISSN 1544-1016, Vol. 22, no 5, p. 659-670Article in journal (Refereed)
    Abstract [en]

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

  • 167.
    Gupta, Mohit Kumar
    et al.
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Nylén, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    A modelling approach to design of microstructures in thermal barrier coatings2013In: Journal of Ceramic Science and Technology, ISSN 2190-9385, Vol. 4, no 2, p. 85-92Article in journal (Refereed)
    Abstract [en]

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

  • 168.
    Gupta, Mohit Kumar
    et al.
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Nylén, Per
    University West, Department of Engineering Science, Research Enviroment Production Technology West.
    Design of Low Thermal Conductivity Thermal Barrier Coatings by Finite Element Modelling2011In: Surface Modification Technologies XXIV: SMT24, Dresden, September 7-9, 2010 / [ed] T. S. Sudarshan, Eckhard Beyer, and Lutz-Michael Berger, 2011, p. 353-365Conference paper (Refereed)
    Abstract [en]

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

  • 169.
    Gupta, Mohit Kumar
    et al.
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Nylén, Per
    University West, Department of Engineering Science, Research Enviroment Production Technology West.
    Structure-property Relationships in Thermal Barrier Coatings by Finite Element Modelling2012In: Surface Modification Technologies XXV : proceedings of the Twenty Fifth International Conference on Surface Modification Technologies: SMT25, Trollhättan, June 20-22, 2011 / [ed] T. S. Sudarshan, and P. Nylén, [Chennai]: Valardocs , 2012, p. 175-184Conference paper (Refereed)
    Abstract [en]

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

  • 170.
    Gupta, Mohit Kumar
    et al.
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Weber, André
    Karlsruhe Institute of Technology, Germany.
    Markocsan, Nicolaie
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Gindrat, Malko
    Oerlikon Metco, Switzerland.
    Electrochemical Performance of Plasma Sprayed Metal Supported Planar Solid Oxide Fuel Cells2016In: Journal of the Electrochemical Society, ISSN 0013-4651, E-ISSN 1945-7111, Vol. 163, no 9, p. F1059-F1065Article in journal (Refereed)
    Abstract [en]

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

  • 171.
    Gupta, Mohit Kumar
    et al.
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Weber, André
    Karlsruhe Institute of Technology, Germany.
    Markocsan, Nicolaie
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Helden, Nadine
    Oerlikon Metco, Germany.
    Development of plasma sprayed Ni/YSZ anodes for metal supported solidoxide fuel cells2017In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 318, p. 178-189Article in journal (Refereed)
    Abstract [en]

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

  • 172.
    Gustafsson, Andreas
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Modalanalys av ett lågtrycksturbinhus till en jetmotor2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

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

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

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

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

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

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

  • 173.
    Gustafsson, Fredric
    et al.
    University West, Department of Engineering Science.
    Ulldal, Jonatan
    University West, Department of Engineering Science.
    Optimering av smidesgeometri för P-fläns på bakre turbinstativ (TEC)2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

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

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

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

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

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

  • 174.
    Gustafsson, Pontus
    et al.
    University West, Department of Engineering Science, Divison of Natural Sciences, Surveying and Mechanical Engineering.
    Larsson, Patrik
    University West, Department of Engineering Science, Divison of Natural Sciences, Surveying and Mechanical Engineering.
    Utkastbegränsning samt anpassning av krockgardiner vid sidorutor i bagageutrymme2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

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

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

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

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

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

  • 175.
    Gustafsson, Rickard
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Lunde, Petronella
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Möjligheter i restmaterialet från stickindustrin: En konceptstudie2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

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

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

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

  • 176.
    Gustafssson, Filip
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Mattsson, Idha
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Materialflödesoptimering: Siemens2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

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

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

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

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

  • 177.
    Gustavsson Christiernin, Linn
    et al.
    University West, Department of Engineering Science, Division of Production Systems.
    Augustsson, Svante
    University West, Department of Engineering Science, Division of Production Systems.
    Interacting with Industrial Robots: A Motion-based Interface2016In: AVI '16 Proceedings of the International Working Conference on Advanced Visual Interfaces / [ed] Paolo Buono, Rosa Lanzilotti, Maristella Matera, New York: ACM Digital Library, 2016, p. 310-311Conference paper (Refereed)
    Abstract [en]

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

  • 178.
    Göransson, Daniel
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Haaga, Jerry
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Framtagning av en mobilhållare för bilar2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

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

  • 179.
    Hadzic, Mirella
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Stridsberg, Louise
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Tejp som kraftöverförande fogmetod: en kartläggning2018Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor’s thesis is a survey of adhesive tape as a force-transmitting bonding method in partnership with TechROi Engineering, Trollhättan, Sweden. TechROi Engineering is a consulting company that works with design solutions frequently for the automotive industry and the manufacturing industry. The company wishes to implement taping as a bonding method but wants to evaluate the strength of the adhesive joint. A matrix that consists of characteristics of the tapes and established requirements are conducted with the purpose to enable an obtainment of correlations. The identified requirements are of surface preparation prior application of adhesives and its effects on the durability and the strength of the joint. Two methods for surface preparation is degreasing and abrasion. Further, factors and thus requirements are identified that are necessary whilst conducting an analysis and experiments of the strength of the adhesive joints. The identification of requirements for strength tests are done so with the benefit of a number of selected standards as well as previously conducted tests by researchers. The test methods are primarily intended to evaluate the mechanical properties such as fracture toughness and are sorted in the report depending on the fracture modes. Mode I, mode II and mixed-mode are studied in this thesis. The standardized test methods contain guidelines regarding how the tests shall be conducted. There is an importance to execute the tests, preparations and calibration according to the same circumstances. There is a need to rank the requirements although this may prove difficult since it depends on the application in which the adhesive joint shall be. Additionally, the occurrence of conflicting requirements is dependent on the application. Difficulties with obtaining test methods for mixed-mode arise, particularly due to the absence of standardized tests.

  • 180.
    Hagqvist, Petter
    et al.
    University West, Department of Engineering Science, Division of Automation Systems.
    Christiansson, Anna-Karin
    University West, Department of Engineering Science, Division of Automation Systems.
    Heralic, Almir
    GKN Aerospace.
    Automation of a laser welding system for additive manufacturing2015In: Proceedings of the 2015 IEEE International Conference on Automation Science and Engineering / [ed] Kazuhiro Saitou, Univ. of Michigan, IEEE, 2015, p. 900-905Conference paper (Refereed)
    Abstract [en]

    This paper presents the benefits and challenges ofusing a standard robotised laser welding cell for additive manufacturing(AM). Additive manufacturing, sometimes denoted3D-printing or rapid prototyping, has lately met strong interestin several areas of society, and a variety of technologies andmaterials have been in focus. The current paper summarisesautomation efforts for AM of advanced aero engine componentsusing high power laser with welding optics as power source formelting metal wire and using an industrial robot for obtaininga 3-dimensional feature shape. The challenges are related to theprocess itself encountering high and repeated temperatures withmelting and solidification of the metal as the main players. Themajor research solutions discussed in this paper are relatedto automation issues for obtaining a stable process and tohave control of the temperatures and temperature changes thatthe metals encounter during the process. The solutions aresuccessfully implemented in an industrial laser welding cell.

  • 181.
    Hall, Maria
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Henriksen, Sara
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Identifiering av mätetal för att öka effektiviteten inom inköp2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is performed at GKN Aerospace Sweden AB (GAS) in Trollhättan with purpose to map the purchasing process and find indicators to make the process more efficient. The target is that by the end of March 2016 to be able to determine if the efficiency of the purchasing process can be measured. The thesis has been limited to find metrics for the purchase of production materials and delimited to map the purchasing process from "purchase requisition" to stock. The thesis is a qualitative study and has been carried out through interviews, observations, benchmarking, concept screening and mapping in terms of a BPI-workshop. During the BPI-workshop a number of roles in the process participated to map the "current state", which contained 38 wastes. Based on the "current state" 15 improvement proposals was generated which GAS should implement to achieve "future state". If the proposed improvements are introduced the lead time for the process is expected to reduce from 96 to 42 days.Of the three companies that were visited during the study none of them had metrics for how efficient their process is. The companies including GAS only had measures for how well the suppliers are performing and other measurements for the internal process. The conclusion is that it is difficult to find a single metric that can represent the efficiency of the entire purchasing process, because of its complexity that is influenced by many factors. The only metrics the students suggests GAS to measure for the defined process is: Number of incorrect purchase requisitions The metric does not measure how efficient the process is, the metric will only measure how often errors occur which creates an inefficient process. In order for the metric to be relevant GAS need to implement the proposed improvements that were generated during the BPI workshop.The metric should be measured before and after the implementation of the improvement proposals to achieve the desired effect. Besides this metric, the students suggest GAS to measure the following metrics to eventually get an efficient process: Continuous improvement purchase Finally GAS is urged to continue to implement BPI-workshops for other parts of the purchasing process to identify wastes that are not discussed in this thesis.

  • 182.
    Hallqvist, Alexandra
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Effektivisering av genomloppstid inom termisk sprutning2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of the thesis was to investigate possible ways to increase the throughput efficiency for a part that is thermally sprayed at GKN Aerospace in Trollhättan.

    The goal of the project was to identify technical solutions that can reduce the lead time for the part by at least 40 % and to investigate improvements that could increase the efficiency for all the products that are coated at the department. The project was carried out because the part had one of the longest process times at the department due to a lot of handwork, masking, low-power spray gun and multiple machine stops during the spray operation. The process has been observed and employees have been interviewed to map the current state. Process documentation and part drawings have also been investigated to understand the requirements and ensure that the solutions are useful for the department. The time each activity took were mapped during the observations. Based on the recorded times histograms were made to investigate which moments are most time consuming and therefore needs to be improved. Through the interviews, observations and the benchmarking, solutions were found and further investigated and assessed to identify which ones are the most effective and implementable. Together with operators and technicians, the possible solutions were discussed for in terms of feasibility and improvements. The technicians also discussed the possible time reductions per activity that the proposed solutions are expected to entail when implemented. To achieve the goal, the masking needs to be changed as the masking tools cause the bouncing of coating on the tools and back on the gun, which makes necessary to stop the spraying process after each stroke. If the masking tools are redesigned, a five-hour deburring operation that is performed at another department can be eliminated.

    The conclusion from this work is that it is possible to increase the process efficiency by 49.5% if the existing spray gun is used. If a higher-powered gun can be employed, it enables further efficiency improvement. The increased efficiency of the process makes it possible that the lead time can be shortened from seven days to four days as the part can be completed in the department.

  • 183.
    Hallström, Kristoffer
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Olofsson, Björn
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Förslag på utformning av en monteringscell för att öka produktionskapaciteten: för VP1-pumpar på Parker Hannifin AB2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This work has been carried out at Parker Hannifin in Trollhättan and is describing concept work for design proposals of an assembly cell in which a hydraulic pump is produced. The current assembly cell does not have a high enough capacity to meet a rising demand. The aim of this work was to propose a balanced assembly cell whose capacity increases with increase in the workforce. The goal was to present a model of an assembly cell that can achieve a production capacity of at least 200 pumps per week.By observing the current assembly, and study the various operations time duration, different time balancing charts were created. Unlike the current time balancing charts the operations for calibrating and controlling the pumps functions in a test rig were now included. Various concepts were created and discussed with stakeholders and were followed by revisions of the concepts before a screening. The concepts were screened down to two concepts, which were modeled in full scale to allow for evaluation according to the working method Production Preparation, 2P. After that, a concept point matrix was created and the concepts were rated with the use of the evaluation of the models.The concept recommended to Parker is called "Two-sided assembly" and is a concept where the majority of the sub-assemblies for building a VP1 pump is made on one side and then transported on a roller conveyor to the other side where a smaller amount of sub-assemblies is made to be followed by the final assembly.The concept with the examples of time balancing charts results in a production capacity of 227 pumps per week. The concept is flexible and can be adapted to several workflow standards and there is potential for further development if the concept is deemed suitable to implement by Parker.

  • 184.
    Halmsjö, Jesper
    et al.
    University West, Department of Engineering Science, Divison of Natural Sciences, Surveying and Mechanical Engineering.
    Hansen Andreasson, Karl
    University West, Department of Engineering Science, Divison of Natural Sciences, Surveying and Mechanical Engineering.
    Påläggssvetsning av kylturbulatorer med kall metallöverföring2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Siemens Industrial Turbomachinery in Trollhättan, Sweden, manufacture combustion chambers for gas turbines. One of the most important products is the combustion chamber of the SGT-800 gas turbine. Cooling ribs are currently machined out of the combustor casing. Their purpose is to cool the construction by generating turbulence from the air flow.

    Siemens want to investigate the possibility of replacing the current manufacturing method with an additive manufacturing method. This study focuses on investigating the possibility of utilizing Cold Metal Transfer technology (CMT). CMT is derived from MIG/MAG and offers a lower heat input and splatter free welds. An implementation of CMT-technology would theoretically lead to reduced lead- and transport times as well as cost savings.

    A quantitative study involving CMT-welding was carried out at PTC, Trollhättan. The aim was to create welded ribs of a certain geometry and size. Factorial design of experiments was used. Regression models of how welding parameters influenced the height, width, angle, penetration and heat transfer of the welded rib were created. The regression models were based on the results of the experiments. Optimization of the process led to ribs with good metallurgical properties, free from cracks and lack of fusion. The dimensions were within the required limits. The optimized process was used to weld a zigzag pattern, which is believed to enhance the level of cooling. All experiments were limited to flat surfaces 

  • 185.
    Hamatuli, Cliff
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Skräddad mikrostruktur av gadolinium zirkonat baserade värmebarriärbeläggningar som utsätts för termisk cyklisk utmattning2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Yttria Stabilized Zirconia (YSZ) is the standard ceramic top coat material used for TBC application. Above 1200°C, issues such as CMAS (Calcium Magnesium Alumino Silicates) infiltration susceptibility, phase instability and high sintering rates limits its long durability. Therefore, new materials which can overcome these challenges without compromising the other requirements for TBCs are highly desirable. Gadolinium zirconate is one such material which has shown promising results for CMAS infiltration resistance. In this work, a relatively new TBC processing route, suspension plasma spray (SPS) has been employed to deposit gadolinium zirconate based TBCs. The primary aim of this study was to deposit two different coating systems (layered and composite) of gadolinium zirconate and YSZ composition using SPS technique and evaluate their thermal cyclic fatigue life performance. The layered system was a triple layered TBC with YSZ as the base layer, relatively porous GZ as the intermediate layer and dense GZ as the top layer. The blended TBC system comprised of a thin YSZ layer, an intermediate GZ+YSZ thick layer and dense GZ top layer. In the thermal cyclic fatigue test at 1100°C and 1200°C, it was observed that blended TBC had a lower thermal cyclic life than the layered TBC. It was shown that SPS is a promising technique to deposit columnar microstructure TBCs. 

  • 186.
    Hamid Elamin, Hamed
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Mohammad Taher, Handrin
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Utveckling av en skopkonstruktion med lägre produktionskostnader2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is about the development of a bucket design; intended for a range of excavatorbuckets consisting of four different types, but has only been implemented on the cablebucket. The work has been performed on behalf of a company that develops, produces andsells construction equipment for excavators and wheel loaders. At the present, the company'sexcavator buckets have high production costs, but the vision is to get into the low-costmarket. The goal of this work has been to develop a bucket design that reduces the company'sproduction costs.After a meeting with the company it became clear what needed to be achieved. The collectedneeds were interpreted in terms of customer requirements. A QFD was made, and thecustomer requirements were translated into product specifications for a successful bucketdesign. Particular focus has been put on simplifying the assembly of the bucket and adaptingits design for robot welding. Some essential factors have been to design interactingparts and to consider the accessibility for welding. The concepts were generated throughinternal and external searches, where methods as brainstorming and competitor analysiswere used.Concept selection was made by using Pugh's decision-matrix. A relatively optimal conceptwas selected for further development. During the development, various verification methodswere used, as for example risk analysis, finite element analysis (FEA) and cost estimate,to verify that the selected concept meets the set requirements for the excavator bucket.Several potential improvements were identified during the verifications phase and theseimprovements were implemented on the selected concept, which resulted in an even betterconcept than before.The final concept obtained a reduced production cost, with a more efficient assembly, reducedmaterial use and welding as well as a better performance than before.

  • 187.
    Hansson, Anders
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Detection of tool wear in drilling based on axis position signals2016Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Cutting operations are important and commonly used operations in the field of manufacturing. Automated machining is today commonly used in CNC-machines. One common drawback with automated machining is that the tool condition is challenging to predict which leads to a conservative tool replacement times. This leads to a low utilisation of the tool economical lifetime and an unnecessary high number of tool replacements. Methods for indirect continuous monitoring of the tool wear exist but usually require retrofitting of external sensors that can be both costly and also interrupt the machine operation due to the additional wiring. It is therefore of interest to investigate the possibility to use the, often high resolution, sensors already fitted in a CNC-machine to extract valuable data that can indirectly give an estimation of the tool condition.

    This thesis work has, with attention to the X-, Y- and Z-position sensors, resulted in development of algorithms that show relations between tool wear and data acquired from these sensors. The algorithms operate in the frequency domain to determine changes in the dynamic response over the time of tool degradation.

  • 188.
    Hansson, Hedvig
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Karlsson, Mattias
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Review of stable gas and its safety applications2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis has been performed at Autoliv Sverige AB in Vårgårda. The purpose of the thesis was to increase Autoliv’s knowledge regarding stable gas and its safety applications. To achieve this, a literature study, eight interviews and patent searches has been performed. To broader the understanding further, a concept study of an inflatable life buoy has been made. This idea was presented during a brainstorming session with nine employees at Autoliv. There are some certain characteristics that differentiates gas from solid and liquid substances. The first characteristic is that gases does not have a specific shape or volume. The volume is determined by the size of the container. Another property of gas is that it could be compressed to decrease its volume. The last characteristic is that a contained gas obtain pressure against all walls in the container. If the temperature increases, the pressure will increase as well. In this thesis, stable gas is defined as gases that not react with other gases when it is let out in the air. An unreactive gas means that the valence shell is full and that no electrons are missing or needs to be bound to another molecule. This corresponds to stable gases, for example the noble gases that is presented to the far right in the periodic table of elements. There are several safety products on today’s market that uses stable gas. This thesis includes a screening of three variants of inflatable vests, a bicycle helmet and a lifeboat. These products activate in different ways, both automatically and manually. The purpose of the life buoy was to do design a product that is easier to throw and takes less space than a traditional life buoy. Thus, demonstrate how stable gas can be applied in a real-world scenario. A complete solution has not been developed in this thesis due to the limiting time factor. Basic constraints, such as pressure and volume were calculated to show the necessary requirements on the buoy and the cylinder. The concept study of the inflatable life buoy resulted in a buoy of 35 litres with a cross section diameter of 1.6 dm. To be able to inflate this volume, a cylinder containing 90 ml is required. The dimensions of the cylinder have been calculated to minimize the use of material which resulted in a height and diameter of 50 mm. One of the conclusion of this thesis is that stable gas is useable for safety applications. The choice of gas depends on the specific product and its conditions and requirements. Therefore, a specific gas cannot be considered as the most optimal.

  • 189.
    Hansson, Jonas
    University West, Department of Engineering Science.
    Integrated Management Systems – advantages, problems and possibilities2010In: 13thToulon-Verona international quality conference. 2-4 sept, 2010: Organizational Excellence in Service, 2010Conference paper (Refereed)
    Abstract [en]

     Effective management in the globalized world requires an effective, efficient and flexible management system. Effective could be interpreted as addressing all relevant stakeholder concerns in a context of Corporate Social Responsibility (CSR). Efficient would mean that it does the job with low resource use. Flexibility requires that changed conditions and new requirements easily can be included. Many organizations are already working with Integrated Management Systems (IMS). Interesting questions are to what extent current integration covers the above mentioned needs and if not what changes are needed. This conceptual paper looks at the advantages and problems of integration. Possibilities for development of fully integrated management systems are studied from the perspective of managing stakeholder needs, with the forthcoming ISO 26000 – “Guidance on social responsibility”, as inspiration. Results show that there are advantages in integration, but that the scope and level of integration often is limited. A conceptual model for integrating all stakeholder needs in value networks is presented.

  • 190.
    Hansson, Jonas
    et al.
    University West, Department of Engineering Science, Division of Process and Product Development.
    Klefsjö, Bengt
    Luleå University of Technology, Division of Quality and Environmental Management.
    Sustaining quality management implementation in small organisations: Experiences from quality award recipients2008In: International Journal of Management Practice, ISSN 1477-9064, Vol. 3, no 1, p. 31-50Article in journal (Refereed)
  • 191.
    Hansson, Mattias
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Palmgren, Mats
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Product Development: Steering solutions for Easy Boating2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor's thesis consists of a product development project performed for Volvo Penta's transmissions department. In line with Volvo Penta's vision of Easy Boating, the problem description entailed, to make boating easier by developing concepts for the steering of boats. The goal was to develop three concepts which suited the requirements provided by the project owner. The bachelor's thesis was preceded by a study, in the form of a concept generation process. The project was initiated with a concept generation process, in parallel with a requirement analysis. This concept generation was performed with the assistance of tools from the Teoriya Resheniya Izobretatelskikh Zadatch (TRIZ) methodology. Utilised parts from TRIZ are tools for identifying free resources, finding and resolving undesirable contradictions and predicting the next step of development of a system. In accordance with the methods of Set-Based Engineering, the generated concepts were not chosen for their merit, but instead eliminated based on requirements and developed knowledge. To accomplish this, the requirements were collected from the identified stakeholders of the project and ranked based on their respective weight. The requirements were used in the elimination of the concepts which was performed in three stages: pruning of concepts, concept screening and ultimately, concept scoring. These three stages were based on the literature and chosen because of their ability to incorporate the requirements in the elimination. As a result of the elimination process six concepts of two different product categories, addons to existing solutions and complete new systems, were presented to Volvo Penta in combination with a product development plan. The result of six concepts was obtained since none of the concepts categories could be eliminated by the requirements collected in the process and therefore it was decided to present tree from each category.

  • 192.
    Hansson, Tobias
    et al.
    University West, Department of Engineering Science.
    Skogsberg, Kristoffer
    University West, Department of Engineering Science.
    Comparison of stress behaviour in thermal barrier coatings using FE analyses2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The objective of this thesis project was to compare the stress behaviour in thermal barrier coatings (TBCs) with FE analyses in both 2D and 3D. The main focus was to analyse the vertical stresses in the topcoat (TC) and how they varied in relation to different thicknesses of the thermally grown oxide (TGO), spraying methods of the bondcoat (BC) and the topography of the BC.

    For the 2D simulations six samples were used; three with BCs sprayed with high-velocity oxy-fuel spraying and three sprayed with atmospheric plasma spraying. The samples had been exposed to isothermal heat treatment at 1150 °C for 0, 100 and 200 hours. Five images of each sample were taken with a scanning electron microscope, resulting in a total of 30 images. FE simulations based on these 30 images were done simulating a cooling from 1100 °C to 100 °C.

    The 3D simulations were based on surfaces created from coordinates measured with stripe projection technique on three samples consisting of only substrate and BC. Three domains of each sample had been measured and three CAD models based on randomly selected surfaces of each domain were made, resulting in 27 CAD models. The CAD models were used in the 3D FE simulations also simulating a cooling from 1100 °C to 100 °C.

    The results showed that the 2D simulations corresponds to published assertions about a stress inversion after TGO growth and that cracking will propagate from one peak to another, presuming the roughness of the TGO can be expressed as a wave. No conclusions of differences between spraying methods of the BC could be drawn.

    The stress inversion phenomenon was also found in the 3D simulations. By inspecting the TGO/TC-interface profile in different sections of a 3D model, difficulties in predicting the stress behaviour in a TBC with 2D were explained. No differences in stresses in relation to the BC roughness could be stated.

  • 193.
    Haraldsson, Jenny
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering.
    Karlsson, Christian
    University West, Department of Engineering Science, Division of Mechanical Engineering.
    Ersättning av skruvförband till VE152012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Fordonsindustrin strävar efter ständiga förbättringar på transmissionssystem inom exempelvis hållfasthet och viktminskning. För att reducera vikten på växellådshuset (VE15) har alternativ till det befintliga skruvförbandet granskats. Målet med examensarbetet var att välja två olika fogningsmetoder, en inom svetsning och en inom limning. De valda fogningsmetoderna jämfördes med det befintliga skruvförbandet utifrån bland annat viktminskningspotential och hållfasthet.

    Information inom svetsning, limning, skruvförband och aluminium införskaffades med hjälp av kvalificerade databaser, vetenskapliga artiklar samt rådfrågning av sakkunniga inom respektive område. Utifrån de valda fogningsmetoderna, friktionsomrörningssvetsning (FSW) och epoxi, idégenererades utformning av flänsen.

    Vid användning av FSW som fogningsmetod reducerades vikten på VE15 med 13,7 % och med epoxi var viktminskningen 25,5 %, i jämförelse med skruvförbandet. Då mekaniken i växellådan genererar krafter på flänsen är hållfasthetsegenskaper hos fogningsmetoderna viktiga. Epoxi, FSW och skruvförbandet klarar belastningarna med god marginal. Med avseende på bland annat hållfasthet, vikt och miljö/hälsopåverkan valdes FSW som potentiell ersättare av skruvförbandet på VE15. Valet utfördes med en konceptvägningsmatris.

  • 194.
    Harati, Ebrahim
    et al.
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Malek Ghaini, Farshid
    Tarbiat Modares University,Tehran.
    Torkamany, Mohammad Javad
    Tarbiat Modares University, Tehran.
    Microstructural Analysis of Laser Cladding of Stellite 6 on Ductile Iron2014In: Proceedings of The 6th International Swedish Production Symposium 2014 / [ed] Johan Stahre, Björn Johansson,Mats Björkman, 2014, p. 1-8Conference paper (Refereed)
    Abstract [en]

    Stellite 6 alloy in the form of powder was deposited on a ductile cast iron substrate using a low power pulsed Nd:YAG laser. The effects of process parameters on the resulting microstructure and hardness were studied with emphasis on the single and multi-track deposits. The results revealed that the cladded layers consist of carbides dispersed in a Co-based solid solution matrix with a dendritic structure. Multi-track cladded layers have coarser dendrites compared to those of single-track cladded layer due to a longer exposure time at high temperature and slower cooling rates as more layers were deposited

  • 195.
    Hardan, Salem
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    AL-Rumaiss, Hussain
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Simulering av produktionsflöde före produktionsökning i Volvo Penta, Varafabriken2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Volvo Penta, Varafabriken has planned to close by the end of 2019, another engine variant under the name Compact Engine will begin to be produced in the factory. According to the plan, the number of engines to be produced is estimated at seven hundred engines. This means that the plant will produce three to four engines daily of this variant. The new engine will use the same flow as three other engines already produced in the factory. The new Compact Engine variant has undergone a major change before production, which means that more than 80 percent of the included parts were changed for the purpose of achieving higher performance, reducing emissions and increasing reliability in maneuvering. The motors manufactured in the current production flow are used almost entirely in boats and the new variant has sailboats as a target group.

    The engineering department responsible for the planning and implementation of the production wanted the project work, which is reported in this paper, to analyze the flow and carry out a simulation project to map the maximum capacity of the system in the form of manufactured engines and to predefine batch sizes for the plant if the production pattern for upcoming engine variants into the flow can affect production capacity. The latter goal for batch sizes has been a secondary target that is desired if the time is enough and it did. The project team has never used the software, FACTS ANALYSER, which the factory uses as a simulation system.

    The project resulted in the production inflow two being able to increase the number of engines produced by as much as 35.29 percent. The simulation showed that the number of motors produced would increase from 34 to 44 engines per shift, which is an increase of 12 engines per shift. The simulation also showed that the bottleneck would occur at Station 835, but that the painting with its components, robots, and the furnace had the highest utilization rate of 90.3 percent.

    After analysis of the result, one could draw a conclusion that the painting can appear as a future bottleneck if Volvo Penta decides to reduce the processing time at Station 835 which is assumed to be the bottleneck by, for example, that more operators can be supplied to reduce the processing time. A simulation with changed batch sizes was run and showed no differences in the TH value.

  • 196.
    Hatefipour, Saeid
    et al.
    University West, Department of Engineering Science, Division of Automation Systems. saeid@termisk.se.
    Ahlberg, Jörgen
    Linköping University.
    Wren, Joakim
    University West, Department of Engineering Science, Division of Automation Systems.
    Runnemalm, Anna
    University West, Department of Engineering Science, Division of Automation Systems.
    Thermal non-destructive testing: modeling, simulation and experiments for improved localization of hidden defects2014In: The 12th International Conference on Quantitative Infrared Thermography, 2014, p. 1-8Conference paper (Refereed)
    Abstract [en]

    During the last decades, a substantial amount of research and practical work has been conducted on non-destructive testing of materials using thermography. The performed studies elucidate the potential of various types of thermal non-destructive testing (TNDT) for different materials and applications, including various types of defects. This paper presents a method for detecting in-depth defects in metallic materials and a simulation model for the heat transfer in the material. Experiments are performed on a test specimen with artificial defects (flat-bottom holes). The detection method exploits spatiotemporal analysis in order to find deviations from a model of normality, and shows novel results. Thermal modelling is performed in order to have a base-line simulation model enable us to (a) investigate affecting parameters without repeating the experiments and (b) generalize the results and extend their validity to other cases. Results show that there is an acceptable compliance between simulated and measured thermal data. 

  • 197.
    Hattinger, Monika
    University West, Department of Engineering Science, Division of Production Systems.
    Researchers design conceptions of e-learning courses targeting industry practitioners’ competence needs2018In: International Journal of Continuing Engineering Education and Life-Long Learning, ISSN 1560-4624, E-ISSN 1741-5055, Vol. 28, no 3-4, p. 235-253Article in journal (Refereed)
    Abstract [en]

    This paper addresses two overall challenges that concern university research teachers' professional identities when they make design plans for blended e-learning courses targeting practitioners' competence needs. Research teachers' are challenged by finding applicable learning material that matches practitioners' experiences and workplace knowledge demands. They are also challenged when they need to digitise engineering learning content such as virtual labs, and machine-related cases such as turning and milling aligning to workplace needs. Design plans used for campus education is argued to be insufficient meeting these challenges. Consequently, researchers' professional identities become vulnerable when they cross boundaries between university and industry practices. Results show that even if researchers are not trained for educational e-learning design they identify concepts for digitising cases and labs. By applying a work-integrated learning strategy, the courses integrate practical and theoretical tasks and cases collected from the manufacturing industry workplaces and thereby support competence development. © 2018 Inderscience Enterprises Ltd.

  • 198.
    Hattinger, Monika
    et al.
    University West, Department of Engineering Science, Division of Production Systems.
    Eriksson, Kristina M.
    University West, Department of Engineering Science, Division of Production Systems.
    Co-construction of Knowledge in Work-Integrated E-learning Courses in Joint Industry-University Collaboration2018In: International Journal of Advanced Corporate Learning, ISSN 1867-5565, E-ISSN 1867-5565, Vol. 11, no 1, p. 10-16Article in journal (Refereed)
    Abstract [en]

    Blended e-learning in higher education targeting company knowledge needs, can support continuous competence development for practitioners in the manufacturing industry. However, university education is traditionally not designed for workplace knowledge needs that strengthen practitioners' learning in everyday work, i.e. work-integrated learning.

    Designing for such learning efforts is even more challenging when the pedagogical strategy is to stimulate practitioners own work experiences as a valuable knowledge source in construction with other peers or teachers. The aim is to explore how engineering practitioners and research teachers mutually co-construct knowledge. In particular, three types of case-based methodologies are examined within a range of industry targeted e-learning courses. The study is part of alongitudinal joint industry-university project. Eleven courses were analyzed through focus group sessions with 110 practitioners from 15 different companies. Results show that 1) Virtual digital cases stimulate high technology learning, but show low collaboration with peers, 2) On-line collaborative negotiation cases stimulate both web conferencing and high interactivity, and 3) Real workplace cases do not stimulate e-learning, but motivate strong work-integrated learning and knowledge expansion.

  • 199.
    Henriksen, Daniel
    et al.
    University West, Department of Engineering Science, Divison of Natural Sciences, Surveying and Mechanical Engineering.
    Lööf, Rebeca
    University West, Department of Engineering Science, Divison of Natural Sciences, Surveying and Mechanical Engineering.
    Fält, Jonas
    University West, Department of Engineering Science, Divison of Natural Sciences, Surveying and Mechanical Engineering.
    Verksamhetsmodell för införande av nya produkter2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report describes a thesis work performed at GKN Aerospace in Trollhättan. The goal of this thesis has been to improve the process for new product introduction with focus on reducing lead time, cost and quality issues. To describe the work methodology regarding manufacturing preparation and production ramp-up, a proposal for a new business model was created.

    The thesis work has been based on a product development perspective. Information was gathered from interviews with GKN Aerospace employees and literatures about different work methodologies.

    To define final requirements for the business model, customer needs was identified and weight relative each other. As the final requirements were defined, a number of concepts were created and end one of them was selected for further development.

    The thesis work resulted in a new business model where work methodology and instructions are documented in a handbook. The handbook describes the different phases of the business model and a short presentation of the involved functions along with input and output. The purpose of the handbook is to be used as a tool for project managers and employees in the start-up of new products.

    For further development and implementation of the new business model, a document was created where potential risks have been analyzed and recommendations regarding implementation of the new business model are described

  • 200.
    Heralic, Almir
    University West, Department of Engineering Science.
    Towards full Automation of Robotized Laser Metal-wire Deposition2009Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Metal wire deposition by means of robotized laser welding offers great saving potentials, i.e. reduced costs and reduced lead times, in many different applications, such as fabrication of complex components, repair or modification of high-value components, rapid prototyping and low volume production, especially if the process can be automated. Metal deposition is a layered manufacturing technique that builds metal structures by melting metal wire into beads which are deposited side by side and layer upon layer. This thesis presents a system for on-line monitoring and control of robotized laser metal wire deposition (RLMwD). The task is to ensure a stable deposition process with correct geometrical profile of the resulting geometry and sound metallurgical properties. Issues regarding sensor calibration, system identification and control design are discussed. The suggested controller maintains a constant bead height and width throughout the deposition process. It is evaluated through real experiments, however, limited to straight line deposition experiments. Solutions towards a more general controller, i.e. one that can handle different deposition paths, are suggested.

    A method is also proposed on how an operator can use different sensor information for process understanding, process development and for manual on-line control. The strategies are evaluated through different deposition tasks and considered materials are tool steel and Ti-6Al-4V. The developed monitoring system enables an operator to control the process at a safe distance from the hazardous laser beam.

    The results obtained in this work indicate promising steps towards full automation of the RLMwD process, i.e. without human intervention and for arbitrary deposition paths.

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