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  • 1.
    Aarenstrup, Filip
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Effektivisering av informationsflödet mellan säljkontoren i orderprocessen inom Höganäs AB2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Höganäs AB is one of Sweden’s oldest companies established in 1797, the company have 1900 employees today and is one of the leading producers of metal powder in the world. From the subsidiary Höganäs Sweden AB 300,000 tonnes of metal powder was dispatched 2015. The material was sent to Höganäs customers that mainly consist of component manufacturers in the automotive, wood and other manufacturing industry.

    The purpose of this thesis is to suggest a new operational working process that will increase the efficiency of the order handling process. Throughout the investigation the present state of the process has been outlined and identified at Höganäs Sweden AB.

    Höganäs AB’s order handling process consists of many operations and interfaces that are involved to secure high delivery performance to the customers. The complexity of the process increases due to this and demands an effective communication between involved interfaces. The order handling process may vary depending on factors such as delivery terms, payment terms, transport, product, country, customs clearance and quantity. The variation of these factors makes it difficult to implement a standardized approach.

    It is valuable to Höganäs AB to streamline the process. The data recorded in the business system from the customer order is an important basis for production-, dispatch- and planning departments. The recorded data can be obtained earlier if high quality conditions are created that can increase the delivery performance and affect customer relationships positively.

    With support from the collected theory and the study that contains qualitative and quantitative primary data from Höganäs Sweden AB a new working process have been formed that excels the efficiency in the process. The new approach streamlines the overall process time by 40 percent and the overall lead time with 32 percent. In addition to the increased efficiency the number of information exchanges in the process was reduced significantly.

  • 2.
    Abdallah, Karl
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Sisodia, Raoul
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Kvalitetsproblem med inre dörrpanel2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis work has been conducted at International Automotive Components Group in Torslanda, Sweden. The company produces door panels, instrument panels, consoles and cockpits for the automotive industry.

    During the production of door panels, defects such as pressure marks and scratches emerge which results in scrap and rework. The objective of the thesis work was to identify the causes of pressure marks and scratches and also to suggest measures to reduce the amount of scrap and rework on door panels.

    Through observations, interviews and experiments, several causes leading to pressure marks and scratches on door panels were identified. Small pieces of plastics on fixtures, the operator's rough handling and specific process steps are the main causes that result in pressure marks and scratches.

    Pressure marks and scratches emerge at several places on the door panels during the production. To reduce the amount of pressure marks and scratches both short-term and long-term measures were suggested. Some of the measures are:

    •  Use vacuum cleaners at some stations
    •  Add padding on unpadded areas and edges
    •  Make new instructions that emphasize to keep production stations clean and to avoid rough handling
    •  Introduce workshops to engage operators
  • 3.
    Abdallah, Kristian
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Pedestrian Protection System: Hood lift study2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Every year approximately 400 000 pedestrians are killed worldwide in road related injuries where children and elderly are the most exposed age groups. The design of the front-end of a vehicle and the structural stiffness have a significant influence on the kinematics and injury risks of the pedestrian body. To create a clearance between the rigid hood structure and the hood, the hood is lifted. A lifted hood does however not provide protection over the cowl, windscreen and A-pillar areas.

    This study is performed at Autoliv Sverige AB and the purpose is to examine how fast the hood can be lifted 100 mm using a pedestrian protection airbag. The airbag give an extended protection while covering the cowl, windscreen and A-pillar areas.

    A concept generation session was performed where modifications of the current pedestrian protection airbag, for a faster hood lift, were proposed. The generated concepts proceeded to a concept screening session where the Autoliv evaluation matrix was used.

    The selected concepts went further to static testing where the performance of each concept was tested. The performance include the lift time of 100 mm for the most rearward section of the hood, positioning of the cushion and pressure distribution. The tests were carried out in a room temperature environment.

    To conclude the thesis work, one winning concept could not be obtained. Two concepts excelled themselves from all the concepts and a difference in the performances between these two concepts could not be found.

    In this thesis no calculations on costs such as material costs and manufacturing costs has been made. This can be the major aspect on choosing one winning concept but due to the fact that there is no time for a cost analysis in this thesis, the PPA development team will take over.

  • 4.
    Abdulmohsin, Haider
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Prediction of cutting forces for second layer removal in metal cutting process2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Machining processes studies and theories can be referred back to the beginnings of machine age, but recent developments in information technologies (Computers, processors, etc.) make it easier for the researchers to predict material behaviour during different machining processes.

    Machining is not a simple process to analyse due to the amount of variables affecting on it, in this study the author is trying to analyse and explain the forces acting on a AISI 1045 workpiece during the removal of material’s second layer using FEM, one of the challenging problems was to re implement the forces resulted from the first layer removal in the new cutting process to give the study more reliable output to compare with the actual results obtained previously the procedure used to reach this is explained in chapter 3, there are many software used to define FEM analysis each has its benefits and limitations, LS-DYNA which is used in this study is one of those software "it is capable of simulating nonlinear problems involving large deformations, sophisticated material models and complex contact conditions".

    As well as LS-DYNA, HyperMesh and Ls-prepost are used in this study to mesh the tools and workpiece, and pre-set the material parameters respectively.

  • 5.
    Agardsson, Edvin
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Leijer, Malin
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Verktyg för identifiering av tidsåtgång för materialhantering2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Autoliv Sverige AB är ett företag som ligger i Vårgårda och tillverkar airbagar, gasgeneratorer samt elektronik till radarsystem. I framtiden finns planer för att expandera produktionen men i dagsläget vet företaget inte hur mycket resurser som går åt för materialflödet till de olika produktionslinorna. För att ta reda på hur mycket personella resurser som behövs både i befintligt materialflöde och i framtida produktionslinor vill företaget undersöka systemet som matar fram material till produktionen. För att ta fram ett verktyg som gör detta används aktionsforskning som huvudmetodik. Aktionsforskning utgör en iterativ process som består av observationer, framtagning av lösningsförslag och utvärdering av lösningsförslag. Observationerna genomfördes i samband med datainsamlingen där Kanbanrundan undersöktes, definierades och mätetal togs fram. Detta för att få en grundförståelse för vad innehållet i verktyget skulle vara.Nästa steg i processen var framtagning av lösningförslag, vilka skapades med hjälp av benchmarking av interna dokument och informationen som samlats från observationerna. En konceptmodell per person skapades och ett koncept valdes sedan ut som utgångspunkt för fortsatt utveckling av verktyget. Modellen blev sedan granskad respektive förbättrad av medlemmarna och handledaren på företaget i en iterativ process.När modellen ansågs klar verifierades det mot verkligheten och den insamlade datan. Verktyget validerades sedan genom att en anställd på Logistikavdelningen fick testa det. Utöver utvecklandet av verktyget och insamlingen av datan utfördes en benchmarking både internt på företaget och externt på ett annat företag för att studera olika materialhanteringsprocesser.I analysen diskuterades för- och nackdelar med olika val och iakttagelser som gjorts, både i arbetssättet för detta examensarbete och dess olika delar men också för materialhanterarens arbetssätt och instruktioner. Resultatet av arbetet blev ett verktyg som uppfyller de krav som formulerades i början av arbetet. Utöver verktyget upptäcktes även ett flertal förbättringsmöjligheter kring materialflödet och produktionen.

  • 6.
    Agell, Ulrica
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Robotmanipulering med Leap Motion: För små och medelstora företag2016Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    On-line programming of industrial robots is time consuming and requires experience in robot programming. Due to this fact, small and medium sized enterprises are reserved about the implementation of robots in production. Ongoing research in the field is focused on finding more intuitive interfaces and methods for programming to make the interaction with robots more natural and intuitive. This master thesis presents a method for manipulation of industrial robots utilizing an external device other than the traditional teach pendant. The base of the method is a PC application which handles the program logic and the communication between an external device and an ABB robot. The program logic is designed to be modular in order to allow customization of the method, both in terms of its functions and the type of external device that is used for the method.

    Since gestures are one of the most common forms of communication between humans, it is interesting to investigate gestures for the purpose to make manipulation of industrial robots more intuitive. Therefore, a Leap Motion controller is presented as an example of an external device which could be used as an alternative to the teach pendant. The Leap Motion controller is specialised on hand and finger position tracking with both good absolute accuracy and precision. Further, its associated Software Development Kit (SDK) has the capabilities which are required to enable implementation of a teach pendants most fundamental functionalities. Results obtained by a user test show that the developed application is both easy and fast to use but has poor robustness.

  • 7.
    Ahlgren, Rikard
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Dörrich, Wictor
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Processutveckling av förslagsverksamheten vid GKN Aerospace Sweden2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The business world is constantly subject to intense competition that requires continuous development of products, personnel and operations within the company. The development towards a better state comes at the expense of strict requirements in job descriptions where continuous improvement is part of the working role of individuals. In order to link the continuous improvement of the business well-being, there is a need of structured work for improvement in ways of a well-functioning suggestion scheme. Suggestion schemes main purpose is to utilize the experience and knowledge of all employees by encouraging individuals' skills and creativity, which will contribute with innovative and competitive suggestions. Personnel is a resource that covers particular knowledge that no other company can copy; therefore it should be utilized to the maximum extent possible.

    The aim of the project is to identify and specify improvement measures for the suggestion scheme at GKN Aerospace Sweden AB in Trollhättan. The work consisted of an initial literature review, which included direct and indirect factors effecting the continuous improvement with linkage to the proposed suggestion scheme. In order to concretize the theoretical framework of the tools main purpose for the continuous improvement, a theoretical and a practical benchmarking was utilized. The company's current suggestion scheme was mapped and analyzed, and a foundation for future improvements was established.GKN Aerospace Sweden is part of the GKN Group, which operates in more than 30 countries around the world and employs about 50 000 individuals. The company manufactures components for aircraft and rocket engines, as well as service and maintenance. In the current situation GKN Aerospace manages a suggestion scheme that depends entirely on an internal IT system and has an average lead time of 43 weeks until a decision is made. The reward system for received suggestions is an economic reimbursement calculated through a complex formula. The entire suggestion scheme process is extensive and includes several loops for conducting the evaluation of suggestions.

    The thesis resulted in improvement propositions based on studies and situation analysis, but differs from the expected target to improve and develop the current system. The problem that arose was that the current system does not support the company's expectations for the suggestion scheme process. It resulted in a completely new system with associated procedures and reward guidelines were developed to create incentives and higher motivation for the submission of suggestions for improvement. The improvement propositions resulted in: dedicated time for improvements, group-based activities for continuous improvements, start-up meetings, new process, basis for the development of a new IT system, economic and symbolic rewards.Date: 2015-

  • 8.
    Allgurén, Olivia
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Patama, Sanna
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Securing the just-in-time delivery for the after-market: Study at Volvo car customer service2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The thesis has been performed at Volvo Car Customer Service in Gothenburg, Sweden. The output from the study will support Volvo to secure the Just-In-Time delivery of referrals for the after-market. The scope was limited to referrals from pre-planned orders, which occurs when there is no availability in the distribution centre where the orders were placed.

    Volvo's main warehouse in Europe is the Central Distribution Centre, which process referrals. The warehouse had an ongoing organisational change during this study. The concern was that the change would not lead to optimal conditions for processing referrals for different markets. It was therefore important to preserve the market knowledge in order to maintain a reliable referral service.

    A qualitative study was used and the information was gathered primarily through semi-structured interviews. Literature was studied both initially and continuously through the study. Analyse of the literature, current situation and data collection generated ideas for possible ways of securing the referral process and improvements. Benchmarking and Workshop was also performed in order to obtain further ideas.

    The result of this study was an information material containing information about all concerned markets, overview of referral flow and information regarding how the Central Distribution Centre needs to print referrals. The proposals suggested for future work were explained in long- and short-term. The short-term suggestions include use of the developed material in order to preserve the knowledge along with providing correct working conditions. For long-term suggestions focus has been on how to reduce or remove the printing problem. For future work Volvo Car Customer Service should consider these proposals in order to secure and improve the referral service.

  • 9.
    Andersson, Elin
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Boström, Viktoria
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Emballagenedbrytning: Framtagning av förslag till utformning av ny arbetsstation till Volvo Pentas fabrik i Vara2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    AB Volvo Penta manufactures and sells motors and drive systems for marine and industrial applications. The plant in Vara is specialized within manufacturing of marine diesel engines.The plant in Vara is about to go through major changes. The reason is a merger with Volvo Penta Production (VPP) located in Gothenburg. In connection with the merger there is going to be redevelopment of the plant. The station for packaging degradation is going to move and it needs to be redeveloped because it is not an efficient neither ergonomic workstation.The purpose of this project was to develop a suggestion of a new workstation for the packaging degradation. The goal was to develop a suggestion that is more efficient and ergonomically adapted. Data was collected through a situation analysis.To fulfill the purpose the project group performed literature studies, collected data and facts. The theory that was studied focused on lean, station design and layout, work environment and ergonomics. Stakeholders, earlier studies and packaging materials were examined. The next step was benchmarking, the group visited VPP in Gothenburg, Logent AB in Skövde and Mape Sweden AB in Trollhättan. Facts were collected through observations, interviews and a workshop with operators.After that the group studied different flows for the station. The result was to move forward with a parallel flow and a U-shaped flow. Then the group used the flows to form layouts. The final result was a U-cell with the operator and material placed outside the cell. The U-cell is most suitable from a lean perspective and from an ergonomic perspective.Further, today’s station needs to change because it is classified as a risk workstation. The final suggestion for a new station is supposed to work as a guideline for Penta. The suggestion with a U-cell needs to be developed further and more delimitation also needs to be done.

  • 10.
    Andersson, Johan
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    A computational geometry method for centrifugal compressor impellers2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Modern centrifugal compressor impeller geometry often consist of curves and surfaces with a high degree of three dimensionality. This makes the geometry of the impeller difficult to model with commercial CAD-tools. Additionally, in modern optimization processes of impellers the geometry is commonly altered, this puts high demands on the method that is used for generating the geometry. In this work a new computational geometry method for centrifugal compressor impellers is compiled. The new method is designed to be flexible and to support present day optimization processes.The new method is a compilation based upon publications regarding impeller geometry and impeller optimization. It utilizes Bezier curves and B-splines to generate geometry and supports optimization by allowing control points of the constructing curves to be relocated to change the shape of the geometry. To test the new method, a standalone application was successfully developed with the aid of the SCRUM development process. With an easy to use graphical user interface the application generates and displays a 3D model of the geometry generated with the new method.

  • 11.
    Andersson, Martin
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Andreasson, Kristofer
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Parameterization of a B-pillar2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis work has been performed at Benteler Engineering Service in Gothenburg in cooperation with Benteler Aluminium System Norway AS in Raufoss. Since the requirements on a product are changed several times during a product development process in the automotive industry, the desire to develop parts faster has increased. Components with complex geometries can take a large amount of time to design and when requirements on the design are changed the CAD-model has to be remade. A model with a complex geometry, which often is exposed to changes, is the B-pillar in the car. To achieve a more time efficient process for the B-pillar, an investigation was made to see if parameterization of the CAD-model could be made to save time in the development process. The result of this has shown that if the model is supposed to be changed more than three times parameterization is something that should be considered.

    Different strategies for parameterization that could support the development process of the CAD-model of a B-pillar have been compared to investigate which strategy that was best suited for this project.

    The goal to create a CAD-model of a generic B-pillar as a showpiece where parameters control the geometry and where changes of the main dimensions can be implemented faster than in a model without parameterization, has been fulfilled.

  • 12.
    Augustsson, Nathalie
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Löfström, Helena
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Evaluation of the virtual training softwares SeQualia and Vizendo2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The automotive industry is constantly developing and manufacturing industry is facing modernisation and need for increased efficiency which implies that the automotive industry is facing changes for assembly training. To minimise quality errors and save time computerbased training virtual training can be used to practice on product knowledge, variants and sequences. Currently in traditional training in automotive industries, the operators practice on psychical products. The purpose of this bachelor thesis is to obtain knowledge of the effects of virtual training with cycle times longer than five minutes by evaluate the virtual training methods at Scania in Södertälje, Sweden. To achieve the purpose of the thesis the objective is to create a basis of the advantages and disadvantages. Scania is part of the Volkswagen Group and is a world leading supplier in the automotive industry which develops custom made and high-quality products with short lead times. Scania’s core products are heavy trucks, buses and engines for marine and industrial applications. Scania has 46 000 employees in 100 countries. Today Scania use standardised work and Job Instructions Training tools for learning the assembling processes which could be time consuming, ineffective and resource-intensive. Therefore, Scania’s vision with virtual training is to shorten the learning time on-line by implementing virtual training to practice off-line. The main objectives are to reduce the time for training simultaneously as the product quality increases. To obtain reliable information to reach the purpose a qualitative approach has been used in the study. To obtain primary data the methods have been semi-structured interviews, observation and questionnaires that have been performed and literature studies have been used to collect secondary data to obtain a broad knowledge of the subject. Through this the bachelor thesis resulted in recommendations that will contribute to Scania’s decision of future work with virtual training. The recommendations have been based on the previous accomplished studies, results and obtained comments which together were connected in the discussion and by the recommendations the authors believe that Scania can use virtual training with success.   

  • 13.
    Backelin, Christoffer
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Experimental study of trepanning process with nickel-base superalloy sheet, using CO2 laser.2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis experimentally investigates the defect generated at the start and stop zone when trepanning, using CO 2 laser and the nickel-base superalloy Hastelloy X. The project has been performed at Siemens Industrial Turbomachinery AB (SIT) in Trollhättan. Experiments which investigates the effect of altering entrance radius, exit radius (withdrawal) and nozzle distance have been performed. Samples were created by using a Trumpf 2D-laser machine and they were prepared for evaluation by grinding, polishing and etching. The Sample were then evaluated and measured by using an optic microscope. Experiments have been planned according to the method, design of experiments (DOE).

    By using the programme Minitab, regression analysis and empirical models were created which describes the effect of the tested parameters. The results show that it is possible to decrease the start and stop defects by altering of the process parameters.

  • 14.
    Bari, Mahdi
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    A finite element study of shell and solid element performance in crash-box simulations2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis comprehends a series of nonlinear numerical studies with the finite element software's LS-Dyna and Impetus AFEA. The main focus lies on a comparative crash analysis of an aluminium beam profile which the company Sapa technology has used during their crash analysis.

    The aluminium profile has the characteristic of having different thickness over span ratios within the profile. This characteristic provided the opportunity to conduct a performance investigation of shell and solid elements with finite element analysis.

    Numerical comparisons were made between shell and solid elements where measurable parameters such as internal energy, simulation times, buckling patterns and material failures were compared to physical tests conducted prior to this thesis by Sapa technology.

    The performance investigation of shell and solid elements was initiated by creating models of the aluminium profile for general visualization and to facilitate the meshing of surfaces. The meshing procedure was considered to be an important factor of the analysis. The mesh quality and element orientations were carefully monitored in order to achieve acceptable results when the models were compared to physical tests.

    Preliminary simulations were further conducted in order to obtain a clear understanding of software parameters when performing crash simulations in LS-Dyna and Impetus AFEA. The investigated parameters were element formulations and material models. A general parameter understanding facilitated in the selection of parameters for actual simulations, where material failure and damage models were used.

    In conclusion, LS-Dyna was observed to provide a bigger internal energy absorption during the crushing of the beam with longer simulation times for solid elements when compared to shell elements. Impetus AFEA did on the other hand provide results close to physical test data with acceptable simulation times when compared to physical tests.

    The result difference obtained from the FE-software's in relation to physical crash experiments were considered to be varied but did indicate that shell elements were efficient enough for the specific profile during simulations with LS-Dyna. Impetus AFEA proved that the same time to be numerically efficient for energy approximations with solid elements refined with the third polynomial.

  • 15.
    Beno, Tomas
    et al.
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Repo, Jari
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Pejryd, Lars
    Örebro Universitet.
    The Use of Machine Tool Internal Encoders as Sensors in a Process Monitoring System2013In: International Journal of Automation Technology, ISSN 1881-7629, E-ISSN 1883-8022, Vol. 7, no 4, p. 410-417Article in journal (Refereed)
    Abstract [en]

    Tool wear in machining changes the geometry of the cutting edges, which affects the direction and amplitudes of the cutting force components and the dynamics in the machining process. These changes in the forces and dynamics are picked up by the internal encoders and thus can be used for monitoring of changes in process conditions. This paper presents an approach for the monitoring of a multi-tooth milling process. The method is based on the direct measurement of the output from the position encoders available in the machine tool and the application of advanced signal analysis methods.

    The paper investigates repeatability of the developed method and discusses how to implement this in a process monitoring and control system. The results of this work show that various signal features which are correlated with tool wear can be extracted from the first few oscillating components, representing the low-frequency components, of the machine axes velocity signatures. The responses from the position encoders exhibit good repeatability, especially short term repeatability while the long-term repeatability is more unreliable.

  • 16.
    Bergqvist, Anton
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Wellme, Andreas
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Kvalitetssäkring med Visionteknik: Inspektion av monterade produkter2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Tyri Sweden AB is a company that produces LED-lights for heavy vehicles. Tyri wants to investigate if machine vision can help them to assure that gaskets and membranes are assembled to ensure that the end customer doesn't get a faulty product. The purpose of the project is to create an understanding on how machine vision can be a tool to detect faulty products. The goal is to answer the question regarding if machine vision is a suitable technique to detect gaskets and membranes. Another thing that is to be investigated is whether the movement of the object and if light conditions affects the reliability of the inspection method. To answer these questions is a literature study conducted followed by an experiment with the suitable method. The company has previously done studies on threedimensional inspection methods and therefore want the focus to be on two-dimensional methods. The two-dimensional methods that are presented are traditional camera and thermal images. A suitable method is identified based on the literature study and criteria from the company. The chosen method is a smart-camera with software developed by the camera manufacturer. This method is used in an experiment with the purpose to collect data for a statistical analysis to determine how reliable the method is. The reliability is tested via hypothesis testing where it is examined how often the method makes a wrong decision. The null hypothesis states that more than one percent of the decisions are incorrect and the counter hypothesis states that less than one percent are incorrect.

    The experiment is done in a production environment that simulates the production of the company. A smart-camera is placed above a conveyer and each time a product pass below the camera a photo is captured. The photo is then analyzed in a software to identify if gaskets and membranes are assembled or not. Four test runs are conducted where gaskets and membranes are tested separately in either factory lighting or controlled lighting. From the statistical calculations based on the results from the test runs the null hypothesis can be seen as false in three of the test runs. The test run where the null hypothesis is true is when gaskets are being detected in factory lighting.

    A conclusion is then made that machine vision is a suitable method to detect if gaskets and membranes are missing. Another conclusion is that the inspection can be made in a reliable way in spite of the movement of the object as long as controlled lighting is used. Controlled lighting is not as critical if the object to inspect is standing still. Controlled lighting can be used to create shadows to optimize the accuracy of the inspection and therefore the importance of the light can be seen as situational.

  • 17.
    Birgersson, Eric
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Kunéll, David
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Evaluation of logistical capacity and future storage needs at the Technical Material Analysis department of Volvo Cars2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study has been performed at Volvo Car Corporation in Gothenburg, Sweden. Volvo’s Technical Material Analysis department, TMA, has experienced large increases in incoming material quantities since 2015. The objective of the study was to establish a well-founded proposal for improvement that can make the logistical situation at TMA sustainable in a long-term perspective. TMA is a business within Volvo’s Warranty department. Its main purpose is to store material on behalf of other departments within Volvo, and to perform analyses on warranty claims from dealers. In order to collect relevant information, several conventional methods have been used. Semistructured and unstructured interviews were used when studying the business structures and learning about the effects of different departments on TMA. Data collection was performed via archive studies, collecting historical data within Volvo’s internal computer system. Brainstorming and a workshop were used together with TMA staff in order to capture advantages and disadvantages concerning the potential improvement proposals. After the evaluation of a number of concepts, only one remained: to move the business to new facilities. This is considered the only proposal that can establish a long-term sustainable logistical situation for TMA. The other concepts that were considered can potentially solve the current logistical situation, but certainly not tomorrow’s, due to the expected increases in incoming material quantities. The study’s conclusion is thus that the TMA business must be moved to larger facilities, in order to be able to fully maintain its business. The improvements that did not meet the long-term objectives are still considered valuable for the business. They are: Higher inventory turnover and New storage layout with new pallet racks. The implementation of these can establish a better work environment due to decreased amounts of storage, shorter lead times, higher work efficiency and a better over-all control over the storage business.   

  • 18.
    Blomgren, Anton
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Konceptförslag på tunnelkonsol med mugghållare och förvaring2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The background to this project is that Volvo Cars AB wants to give the customer more opportunities to store things in their cars. Today, the customer brings many different objects into their cars, for example cups, bottles and cell phones. The customer would like to have the ability to store these things in a practical and easily accessible way.

    Volvo Cars AB wanted new ideas for the centre stack with focus on the cup holder and storage facilities. The centre stack is the component that are located between the driver's seat and passenger seat of the car where the armrest and gear lever are. The concepts that were developed shall make the centre stack into a more efficient and smarter way to store things. The project was to develop a cup holder that can be used as a cup holder and at the same time as a storage space, a dual functional cup holder. It was also included in the task to find other storage facilities that can improve the centre stack.

    In this project a product development process has been used to produce concepts for the centre stack. By analysing the assignment and the use of brainstorming about 70 ideas was produced. They were reduced to 24 through a discussion with the supervisor at Volvo. Then a discussions was conducted with engineers at Volvo from the interior department, that resulted in eleven concepts remained to be developed further. From these eleven concepts three end concepts were chosen with the help of a decision matrix.

    The three end concepts were two dual functional cup holders and one bottle holder. All these end concepts are easy to apply to the centre stack and are also easy for the customer to use.

  • 19.
    Buvarp, Daniel
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Cost effectiveness of methods for reducing particulate matter emissions from shipping2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Marine diesel engines form particulate matter when the fuel is combusted inside the cylinders. This is due to the fuel and air not being homogenously mixed and chemical processes occurring as a result. These particles are then discarded into the atmosphere together with the exhaust gases, where they then may end up harming humans and the environment. Coal power plants, industry and diesel powered cars and trucks have regulations on them limiting the amount of particulate matter that they may emit. Ships have no such regulations on them yet, but they are expected to come.

    There are many ways that these emissions may be reduced, but the methods also need to have low costs associated with them both considering one time investments and long term maintenance and operation. Since it may soon be relevant for ships to start implementing methods for reducing their particulate matter emissions, there is a need for information regarding both effectiveness and cost for different available mitigation methods. Therefore, this study looked at available methods from this viewpoint and analysed the data. A variety of methods were found, ranging from reducing energy usage aboard, to using nuclear propulsion. Some of the methods were found to be quite effective and others not effective at all. The costs ranged from a net gain to doubling the cost of the ship.

    In the end several recommendations are made in order to provide clear information to the industry about which methods are worth looking in to, and in which circumstances these methods should be used. All ship operators are recommended to increase the fuel efficiency of their ships, reduce energy consumption, and if logistically possible reduce their cruise speed, as well as consider converting to alternative fuels. If those recommendations are not possible or not enough, the use of certain suggested exhaust gas cleaning methods is recommended.

  • 20.
    Carlsson, Ivar
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Reducing variation in the riveting process and measurement system2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the automotive industry the attention to quality has increased. A common concept regarding quality improvement is the Six Sigma methodology. Six Sigma methodology is about improving the process and reducing variation. Six Sigma is a structured method with statistical and management tools to solve quality problems.

    The bachelor thesis was performed at Autoliv Sweden AB and considered improving the company's riveting process. The objective was to suggest potential improvements for the riveting process and the measurement system. The pragmatic approach for the study was to perform a literature study and a data collection. Then the thesis was performed according to the theory with Six Sigma methodology. The riveting process and measurement system were defined, measured and analysed. After the analysing phase potential improvements were suggested.

    The improvements were identified based on literature study, data collection and six sigma methodology. The improvements for the measurement system were operator training, constructing a new measuring fixture, updating the measuring instructions and reconstructing the measuring instruments. The improvement for the riveting process was to implement new levels for each significant factor to attain an acceptable output.

    The conclusion of the study is that if Autoliv Sweden AB implements all the improvements the variation will be reduced in both the riveting process and the measurement system. The improvements will also reduce the potential costs with claims, rework and recalls.

  • 21.
    Dahlberg, Simon
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Implementering av förebyggande underhåll som en del av ISO-certifieringar2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    To become more competitive on the market Stålprofil AB has decided to obtain ISO 9001, 14001 and the upcoming 45001. As a part of this work, Stålprofil would like to implement preventive maintenance on four of the companies machines. This thesis has developed a proposal on preventive maintenance and how the company should implement it. Further an analysis of the company's current maintenance work and a study of the correlation between the three standards and preventive maintenance is carried out.

    A literature study was carried out to gathered information about maintenance. Based on this literature study and the small amount off documentation available at the company a proposal for preventive maintenance was carried out.

    In order to analyze and describe the company´s current maintenance work two observations were carried out. One observations were performed on a scheduled maintenance work and one a corrective maintenance. In addition to this reliability measurement on the four machines was carried out. The measurements should be considered whit great cautions as it only was performed during 900 minutes.

    The conclusions drawn are that the company wasting time by the staff is busy with other tasks and that the maintenance work that was observed was carried out in an unplanned way, even if they were planned.

  • 22.
    Dai, Kaixiang
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Battery cell thermal modelling and fault injection2016Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Lithium-ion batteries are widely used in electrical vehicles due to their high energy density and high discharge current. During the charge and discharge phases, the internal resistance of batteries can generate great amounts of heat. Temperature is a very crucial factor that affects the battery life and safety. The lithiumion batteries’ heat generation and temperature distribution were studied to provide a good reference for designing cooling systems. Furthermore, extreme thermal abusive conditions such as internal short-circuit are also simulated in this project.

    This project was conducted at NEVS in collaboration with University West in Trollhättan. The heat generation of battery cells and fault injection were simulated based on experiments and CFD (computational fluid dynamic) method.

    A number of tasks had to be done in order to build the battery thermal model. The first issue that had to be resolved was being able to gain sufficient physical parameters of Lithiumion battery and this was accomplished through experiments. Once this had been achieved, the final step was to implement the constructed battery thermal model via CFD. The surface temperature of the battery cells was used to validate the simulation model. Three different discharge tests were performed in the experiment part, the discharge currents were 1C, 2C and 3C respectively. The simulated temperatures were compared with real battery temperatures and they were closely corresponding to each other in temperature. Fault injections of the battery were also simulated to have a view on the battery thermal behaviour under extreme abusive conditions. The battery internal shorting has been simulated with different internal resistance and different cross-section areas.

  • 23.
    Danielsson, Rebecka
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Kortläsare för återvinningscentral2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Avfallshanteringen Östra Skaraborg (Waste management Eastern Skaraborg) (AÖS) needs a new card reader for their recycling centers. This project will develop this with consideration to different forms of identification and user friendliness. The project is limited to reading the identification forms of passport, driver's license, European ID-card, national ID-card and ID-cards from banks. The information will be interpreted and translated before it is sent further to the database of AÖS, and after that ends the project's responsibility for the information. Product development methods like concept screening and concept scoring are used. Other tools include programming in C language in a programming environment, design of the box in a computer aided design program and a material selection from a material database.

    Information that steered concept generation and selection were for instance customer demands, climate data, technology in the realm of information reading and the layout of earlier mentioned identification forms.

    The chosen concept is a designed box containing a flatbed scanner (Canon CanoScan LiDE 220) that is connected to a computer (ASUS VivoPC VM42) that is powered on by the user with a start button. This computer is in turn connected to an I/O module (National Instruments USB-6002) that turns on lamps to inform the user if they need to rescan. The computer reads the characters on the ID-card and isolates the personal ID number before sending it in the form of three four digit 16 bits integers via network cable to the database that is localized in a raspberry pi server. The computer does this in its startup routine by first starting the program that scans and turns the scanned information into a pdf, then a translation program takes over that turns the information in the pdf into a string that another program processes to get the personal ID number. This program then sends a signal integer to the I/O-module, and the personal ID number (if found) via Modbus tcp to the database.

  • 24.
    Edström, Johan
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Hammar, Samuel
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Framtagning av beräkningsmodell för uppvärmningssystem: med fokus på kombinationen fjärrvärme och frånluftsvärmepumpar2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    As a result of the EU's environmental 2020 goal, the Swedish government and municipal boards has put up internal goals to reduce energy consumption. EU 2020 goal aims to reduce energy consumption in Europe by 20 percent by the year 2020 from that the target was set in 2010.

    At the municipal level, this has meant that private but mainly public housing properties have been required to review their energy use. The work in this report is based on one of the savings measures that have been taken, which is to supplement existing district heating systems with exhaust air heat pumps. The project aims to develop a calculation model for evaluation and computation for this type of system.

    To create a reliable basis for decisions, efforts were made to produce just calculations. Existing computational models are focused on economic factors and thus takes little consideration of technological aspects and environmental factors. The aim of the work has been to create a computational model which more closely reflects the real situation and demonstrates a more informative decision basis.

    The work began with a literature review which included relevant research and basic facts about exhaust air heat pumps and district heating systems. The calculation model has been developed continuously during the project in which new functions and new information constantly has been added.

    The project has resulted in a working computational model which includes many more parameters than previous reviewed models. Together with the client three sub goals were set up for the model, these were:

    •  To intuitively present information and data.
    •  To create a transparent structure which is simple to follow.
    •  To create a flow through the model, which follows a desired work process.

    These goals are considered to have been fulfilled in the developed calculation model, however, it's possible to further develop this model. The model could, for example, be supplemented with more automated optimization calculations and be adjusted to handle other kinds of heating systems.

  • 25.
    Edvinsson, Åke
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Förbättringsförslag för kyl och värmesystemet i en GasHub-anläggning för Stirlingmotorer2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In 1816 the Stirling engine was invented and has since been tested in a variety of applications. Cleanergy using Stirling technology in its solar and gas plants to produce electricity and heat. The goal of this work is to develop proposals for an energy-efficient way to control the cooling of a GasHub plant to the desired temperatures and draft proposals on combined heat and power solutions known as CHP (Combined Heat and Power). The method of work was to identify how the system looks like, customer visits and the development of proposals for improvement. A GasHub is a facility built out of a container in which this has been designed to connect and place GasBox units. A GasBox is a unit of the Stirling engine, generator and gas burners. A necessary feature of a Stirling engine is its cooling, partly to engine components is not too hot and partly to cool the heated gas. This is because the pressure and volume of gas to be reduced in the cooling phase of the motor to rotate. Cooling and heating system in GasHub linking together all GasBox where glycol mixed cooling water rotates around in a loop. The heat from the Stirling engines is transmitted in the heat exchanger to the cooled coolant from GasHub and in this way is reduced when the heat in the cooling system to Stirling engines. A GasBox produces about 7,2kW electricity when it runs on biogas and 20kW heat energy. The customers who have chosen to install the heating system uses this mainly to heat buildings and land heat outdoors to keep this clean of snow and ice. A GasHub 5 plant produces about 36 kW of electricity. According to the data Cleanergy has estimated the average parasitic loads to about 1.5kW or about 4% of the total energy production. A study was conducted on a GasHub facility in Ulricehamn to, among other things to find out how the customer experienced how large parasite loads were and what could be the reason for this. The calculations are carried out shows that the circulation pump is correctly sized. The pump needs to cope with a delivery height of 9 meters and need a flow of 8.6 m3 / hour. The result has three suggestions for improvement of control system for the cooling presented. The first proposal is control by the temperature, then the circulation pump speed is controlled so that a temperature difference of 12 degrees from the input heat to GasBox and out of this. The second proposal involves driving at various differential pressures for various operating conditions. The third proposal involves installing a thermostat on GasBox to regulate the heat out of it. The improvement proposal is about reducing waste heat and energy are proposed to isolate pipes in GasHub. Calculations show that it is possible to save 35kWh heat-energy per day. The proposals of the CHP solutions suggested that the heat can be used for air conditioning if an adsorptions-chiller is used. It is further proposed that the heat stored in the bedrock and cooling taken from there to cool GasHub. The discussion and analysis section of the report assesses improvement proposals and temperature differential regulation proposal is considered that it is relatively easy to implement and is the most optimal for the circulation flow and lower energy consumption. Among CHP proposals considered to be relatively easy to install an adsorptions-chiller to use the heat to the air. Furthermore, the chapter raises the question whether it would be possible to cool using a lower flow in the system because this could save more energy. The question of whether it would be possible to raise the temperature in the engine of a major gas coolers are used are highlighted. The conclusion of the report states that GasHub is today a fully functional facility for the production of electricity and heat, however, that there is much potential for improvement in the plant. It is found that rules the proposals is estimated to halve the energy consumption of the circulation pump.

  • 26.
    Engman, Linus
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Stanisic, Oliver
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Kravspecifikation som förbättrar förpackningslogistik och arbetsmiljö: En problemlösande studie hos smaksättningsföretaget Santa Maria2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The study presented in the report is a qualitative study conducted by two students at Högskolan Väst. It includes a logistics and a working environment problem at the spice company Santa Maria. The report writers have been told by Santa Maria to review a certain number of articles/commodities that are delivered from different suppliers in a way that makes it unfavorable for employees when they handle the raw materials. The problem can be anything from high pallets, to pallets packed in a way that makes it difficult for employees to handle in certain parts of Santa Maria's production process. To try to fix this, a requirement specification must be prepared which is also the goal of the study. The idea is that Santa Maria will have the opportunity to demonstrate to its suppliers how the raw materials should be packaged and dispatched, and using a requirement specification as a source for decision making. The procedure in the study is based on the steps that follows in a product development process, which means that several different methods have been used to obtain useful information. Such as a current situation analysis, stakeholder analysis, benchmarking and SWOT analysis. Using these methods, we received the necessary information about Santa Maria, such as the current situation, the stakeholders included in the study, and the strengths and threats that the study and requirement specification causes. By carrying out a variety of interviews with Santa Maria, the report writers have gained a good picture and understanding of the problem that the employees experienced.

    The preparation of the requirement specification was based primarily on two aspects, such as economic and work environment aspects. This resulted in a requirement specification that covered both the working environment of Santa Maria employees and the economic aspects, such as how the raw materials should be loaded to optimize loading in a container. With the recommendations made by the report writers, Santa Maria should now have a good awareness of what things that should be improved and how to proceed to get a successful modification.

    The result in the form of the specification was analyzed in the discussion to determine its relevance. This led to the theory and previous research being rooted in the requirements specification. Both theory and previous research were in line with the requirements of stakeholders for the design of pallet goods. The conclusion drawn is that the study is relevant and the problem is appropriate for Santa Maria to consider. By demonstrating that employees' needs are considered, it can gain commitment and motivation can be generated by employees.

  • 27.
    Eriksson, Amanda
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Westman, Anna
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Uppgiftsväxling: identifikation av motstånd och förslag tillförbättringar vid NU-sjukvården2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The lack of nurses is becoming a national problem in Sweden as well in NU-Hospital Group, region Trollhättan and Uddevalla. In 2016 NU-Hospital Group area I of III started a program for switching duties performed by nurses with focus on optimizing the resources. During the winter of the same year as the project started the leaders of the clinics began to resist the change. This year in autumn of 2017, NU-Hospital Group will launch a new program to switch nurses’ duties throughout the organization. This report addresses why the project “task switching” stagnated and what could be done differently in the upcoming program. The purpose of this report is to help NU-Hospital Group to achieve an improvement, avoid resistance from the co-workers and thereby implement a successful program. The authors have completed their work through performing an organizational charting, studying status reports, and applying the methods of literature reviews, interviews, surveys and a compilation of other hospitals achievements and what they have accomplished. These selected methods are chosen to ensure the result is valid and reliable. The healthcare needs to constantly improve their organization. The program “task switching” stagnated because the management perceived the resistance, which was of importance. The change made the leaders of the clinics feel lack of treatment, participation and trust. The purpose and goal of the project was unclear and changed during time. NU-Hospital Group still understand that this change is necessary for the healthcare and therefore they are planning to start the new program of switching duties, which concerns the entire organization. Ahead of the upcoming program the authors have identified a number of suggestions to improve the program. The suggestions are: focus on the project management, focus on the existing processes before switching duties, involvement from the employees and apply a Lean-philosophy. The result of this thesis is considered reliable because several methods have been used and the result have been analyzed from different perspectives. Therefore, we assert the validity and reliability of the study.   

  • 28.
    Eriksson, Matilda
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Samuelsson, Andreas
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Framgångsfaktorer inom partneringanbud: en fallstudie utförd på Peab i Trollhättan2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Peab in Trollhättan have in recent years completed more and more constructions projects in the form of partnering. Partnering means that the buyer mutually plans and implements the project together with the builder. Procurement of partnering projects are done by evaluation of proposals and Peab feels that there are underlying factors for why the proposals win or lose. The aim for this thesis was to present a supportive basis for Peabs proposal process and to increase the possibility of influence the outcome. Method for the study was case study which gave opportunity for deeper knowledge within the area. Through interviews with six buyers and one educator qualitative data could be gathered. Qualitative data was also collected from analysis of former requests for proposals (RFP) from buyers. The current situation analysis was performed with an employee from Peab. During the interviews with buyers and the educator it was confirmed that partnering lacks a definition and a common meaning. There was, on the other hand, a common perception of what partnering is. The buyer’s interpretation and knowledge of partnering can affect the valuation of proposals. Buyers who have knowledge and competence of what partnering is ensures that the request for proposals is based on demanded needs and conditions. As per the buyers, the most difficult part of the evaluation was the interview, since it is subjective evaluation. A balance in knowledge and competence for partnering between the actors would contribute to a more stable process and minimize uncertainty. It is not only the builders proposals process that need to be improved, but also the buyer´s understanding for the evaluation model and demands. Peab ought to implement a process for evaluating contract award decisions. It will generate possibility to improve the proposal process and to develop its activities. The study has identified a number of factors for success to develop the proposal process and Peab should prioritize the following subjects: - Coordinate the knowledge and competence within the organization - Implement a process for evaluation of all contract award decisions - Prioritize the two initial parts of the proposal process  

  • 29.
    Fransson, William
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Svetsbarhetsutvärdering av ATI® 718Plus™: Inverkan av δ-fas2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    ATI® 718Plus™ is a newly developed nickel-based Superalloy. The predecessor, Alloy 718, have been used, among other things, in the turbine part of jet engines due to its ability to maintain its mechanical performance at high temperatures. As the temperature of the turbines is gradually raised to increase the combustion efficiency and reduce emissions, Alloy 718 have disclosed weaknesses. The alternative has been the more expensive alloy Waspaloy which unfortunately shown deficiencies when welded. Welding is a well-used method for this type of products. To replace the Alloy 718, ATI® 718Plus™ was developed as a more cost-effective alternative. Research on Superalloys is done continuously to see how these materials are affected by the extreme environments they are designed for.

    This work investigates how an increased amount of δ-phase affects the weldability of ATI® 718Plus™. δ-phase can transform from the strengthening phase γ" at prolonged exposure to high temperatures, when the alloy is solution heat treated repeatedly. This is expected to occur after repeated heat treatments, that is to say, when being repair welded. δ-phase positively affects the properties of alloys at small concentrations, but negative with more presence.

    The comparison is made between the ATI® 718Plus™ that has been solution heat treated in 954°C for 15 hours and 1 hour. Longer heat treatment results in an increased amount of δphase. Then a Varestraint weldability testing was carried out to compare the crack propagation at different strains. In order to increase the decision base, measurements of hardness and grain size are also implemented as this normally are important factors that affects the weldability. Investigation of microstructure and resulting cracks are carried out using microscopy.

    Weldability test shows an increased susceptibility to hot cracking with more presence of δ-phase. Because hardness and grain size differ minimally the δ-phase is assumed to negatively affect weldability. The hypothesis is that the δ-phase's ability to transform to Laves prompts the crack propagation in the heat-affected zone. The presence of Laves weakens the grain boundaries. This transformation is expected to take place at rapid heating during the welding process.

  • 30.
    Fredriksson, Fredric
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Optimering av skärande bearbetning för detalj tillverkad i höghållfast nickellegering2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The manufacturing industry is met today by increasing demands in regards to both efficient, economical methods for manufacture, as well as better precision. An effective means of meeting these demands is machining processes, such as turning and milling. However, in-creased demands for higher material removal rates (MRR) increase the risks that the ma-chining process is affected by problems as for instance vibrations, which have negative con-sequences on both quality and MRR. In addition, the use of difficult-to-machine materials, such as high-strength nickel-alloys, is increasing. A good knowledge-base of the properties of such materials is required to be able select the correct tools and cutting parameters in order to machine them effectively.

    In this report, the possibilities of reducing tool wear and generating optimized cutting pa-rameters for the processing of a part manufactured from high-strength nickel-alloy was explored. One specific milling operation was examined in regards to vibration problems, tools used and cutting parameters.

    The vibration analysis performed on the tool machine and part was based on the method for vibration prevention developed by prof. Altintas, in which areas of stable, vibration free ma-chining can be identified by performing modal analysis of the machining system.

    Additionally, the tool material and geometry was studied in order to determine suitable tools for the operation as well as determining sets of machining conditions where different tools could be used.

    Analysis of the results in this report shows that the machining operation currently takes place in vibration free conditions. The high rate of tool wear seems to be a result of the poor machinability of the part material. However, suggestions for changes to the cutting parame-ters has been generated that may have a positive impact on the cutting process.

  • 31.
    Gao, Jiaming
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Industrial robot motion control for joint tracking in laser welding2016Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

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

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

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

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

  • 32.
    Gislén, Linda
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Alternative design of robot cell concepts for flexible production2016Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

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

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

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

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

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

  • 33.
    Gislén, Linda
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Agell, Ulrica
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Flödesanalys av orderhantering vid SKF Logistics Services Sweden2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

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

  • 34.
    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.

  • 35.
    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.

  • 36.
    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.

  • 37.
    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.

  • 38.
    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.

  • 39.
    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.

  • 40.
    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.

  • 41.
    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.

  • 42.
    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.

  • 43.
    Hill, Richard
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Solljusdriven avsaltningsanläggning Richard2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this thesis, a concept for a sunlight-powered desalination system has been developed. The work has been based on an original concept that utilizes recycled PET plastic (from for example PET-bottles) and pollution free water. The plastic is shaped in such a way that, together with the pollution free water forms a liquid-filled lens. The water must be particle-free so that no particles can reflect sunlight in the wrong direction. With this type of lens sunlight can be concentrated and focused on a container with salt water, which then evaporates. The evaporated stem is then condensed back to distilled water.

    Methods used for identification of customer requirements were an interview, the study of reports, books, magazines, patents and regulatory framework for similar solar facilities. There has also been some prototype experiments conducted that contributed to the identification of further customer requirements.

    Several of today’s solar concentrating plants have been studied, their advantages and disadvantages have been identified from several literature sources. The methods implemented during the concept generation consisted of sketches, prototype tests and examinations of similar concepts. The choice of the final concept was made with the help of matrices. These showed which met most requirements, by efficiency calculations and prototype testing.

    The result consist of a four-meter long and one meter wide water-filled lens with rounded ends. The lens is used to heat a Receiver filled with salt water. When the saltwater becomes warm enough, the water evaporates into a vapor pipe which is led down through a cooling coil which is in a water tank, the same water tank that distributes saltwater into the receiver tube.

    The solar concentrating lens is made of about 100 kg recycled transparent PET plastic, collected in countries with access to non-recycled plastic debris. It is constructed of two halves which can be used as small greenhouses or as construction parts for large greenhouses. The lens is filled with particle-free water, some alcohol (to prevent the lens from freezing during the night) and a little bleach (to discourage algae formation inside).

    The effect that was calculated showed that a plant with a lens could produce about 55 liters of fresh water per hour. When calculating the manufacturing cost of a lens it was done under the assumption that it would be made in a factory in Kenya, where the recycled plastic cost 1 SEK/ Kg. The total cost became SEK 300 per lens during the first two years. The machinery were presumed to be payed for by the end of the second year, which would lead to a reduced production price and the lenses would then cost 183 SEK each. A preliminary calculation of cost per produced cubic meter of freshwater then gave a final price of 0.75 SEK per cubic meter, which is the cheapest price for desalinated water on the market today, which otherwise is 3.6 SEK ($ 0.56 in 2011) per cubic meter.

  • 44.
    Hillström, Oscar
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Johannesson, Mattias
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Integration of a belt in a seat: Safety in autonomous cars2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The world's first driverless ride on public roads was performed in 2015 by Google with their concept car Waymo. The Swedish transport agency investigated what could be expected to be seen on the market at the year of 2020. Several companies announced that self-driving cars will be produced during 2020 with "Limited Autonomous Driving".

    Autonomous driving is defined in several levels. There is no automation at level 0 and fully autonomous driving at level 4. Consequently, new cars may incorporate interior design with flexible seating positions. In order to achieve this, belt integrated seats, BIS, are a favored solution by the vehicle manufactures, because the seatbelt is mounted on the seat structure, independently from the vehicle chassis.

    Autoliv, which is one of the world's largest automotive safety supplier, were interested to gain increased knowledge about BIS, and initiated this project. The project goals were to examine regulating laws for the design of BIS and to create concepts of how a seatbelt may be integrated in a conventional seat structure. Boundaries were set to limit the research on regulations and also the number of concepts that were generated and evaluated.

    Ulrich and Eppinger's product development process was the primary applied method for the project. Experts at Autoliv and external companies were consulted for guidance and knowledge during the project to validate a more reliable outcome.

    Three regulations that the authors judged to be important in order to validate a concepts performance were the ECE R14, ECE R17 and FMVSS 301. In R14, three static loads shall be supplemented on the seat. In R17, the seat shall withstand displaced luggage which is the dynamic scenario often used to dimension seats. The FMVSS 301 is a dynamic crash test that provides a good indication on the crash performance of the seat.

    The concept generation phase was influenced by an external search consisting of benchmarking and discussions with experts about BIS, which provided a total of five unique BIS positions. The internal search resulted in 13 concepts which were evaluated with a scoring matrix during a group session with the project group and experienced experts.

    The result provides a guidance of where it may be best to implement the seatbelt in the seat structure in terms of packaging, day to day use, crash performance and comfort. Concepts with a webbing guide across the seatback were considered to less feasible due to the luggage crash test in ECE R17, compared to concepts without. Concepts in the upper seatback area received general higher score, due to the increased ride-down efficiency and comfort.

    The project managed to comply with the project goals within the specified timeframe and is satisfied with the outcome, which hopefully is shared by the customers, Autoliv.

  • 45.
    Hiuhu, John
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Shear spinning of nickelbased super alloys and stainless steel2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Shear spinning of Haynes 282, Alloy 718, Alloy 600 and AISI 316L was done using several tool feeds and mandrel clearances. Multi passing of the materials was limited due to strain hardening and circumferential cracking except for AISI 316L. The effect of the tool feed and the mandrel clearance on the successful forming of the materials was established. The successfully spun samples were solution heat treated at varying temperatures and holding times to establish a range of grain sizes and hardness levels. An aging heat treatment process was performed for Haynes 282 and Alloy 718 to achieve precipitation strengthening. The micro hardness measurements were conducted for the materials prior to spinning and after spinning. The same was also done after the various heat treatment processes. Grain size mapping was conducted by the use of lineal intercept methods. Comparison of the results in terms of grain sizes and hardness values was done. The temperature ranges suitable for full recrystallization of the materials after the shear spinning were identified and the effect of the holding times on the grain growth established. Comparison with unspun samples showed that the heat treatment times required to achieve comparative hardness and grain sizes were distinctively different.

  • 46.
    Hjälm, Anton
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Jansson, Henrik
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Development of an All-Terrain Chassis for a Modular Platform Based Electric Vehicle2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report presents the execution of a thesis work regarding the development of a modular chassis for an electric vehicle. The work is based on a concept by Cubix Drives AB. In this thesis work, their concept has been further developed in order to ensure that it can withstand the loads that the components are subject to when the vehicle is being used.

    Throughout the work, by using CAD- and FEA-software's, the components have been designed and exposed for load cases that intends to simulate possible scenarios during off road driving. As the stresses were identified the components have been improved to keep the stress levels below the fatigue limit.

    The components have been assembled into a chassis designed to utilize predetermined components regarding the electric drives, steering mechanism and power source that should be able to withstand the loads that it is estimated to being subject for when driving in a forest environment.

    Suitable manufacturing methods, materials and surface treatments have also been chosen. Further work is required mainly regarding the brake system but also regarding adaption for the electrical wiring and control boxes. Other areas of application for the chassis have also been investigated, such as a boat trailer and a dumper.

  • 47.
    Holmer, Anna
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Carlsson, Lisa
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Tomträttens värdepåverkan vid försäljning: En jämförande studie av radhus i Göteborg2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Köpeskillingen på en fastighet påverkas av flertalet faktorer, såsom läge, utbud och efterfrågan. En fastighet kan ha flera typer av upplåtelseformer, två av dem är äganderätt och tomträtt, där man vid innehav av en tomträtt betalar en årlig avgäld. Avgälden kan ses som en form av hyra till markägaren, som enligt teorin ska vara en prispåverkande faktor. Syftet med studien är att undersöka om tomträtten som upplåtelseform är en prispåverkande faktor. Samt att undersöka om det finns tydliga skillnader på tomträttens värdepåverkan vid försäljning beroende på i vilket område fastigheten är belägen. Studien är en undersökning genomförd på Lantmäteriets sammanställda data av försålda småhus av typen radhus mellan åren 2011 – 2013 i Göteborgs kommun. Det är en jämförande studie med kvantitativa beräkningar med redovisning av den procentuella skillnaden av försäljningspriserna mellan de två typerna av upplåtelseformer. Resultatet av studien visade att det är en prisskillnad mellan försålda radhus upplåtna med tomträtt och försålda radhus med äganderätt, där tomträtterna hade ett något lägre försäljningspris i de flesta studerade områden. I fem av de åtta områdena var medelpriset i kr/kvm för de försålda tomträtten lägre än för de försålda äganderätten. I sex av de åtta områdena var medelvärdet för K/T lägre för de försålda tomträtterna än för de försålda äganderätterna. Avgäldens storlek hade en liten påverkan på prisskillnaden oavsett om fastigheten var belägen i ett billigare eller dyrare område. Tomträtten kan konstateras vara en prispåverkande faktor.

  • 48.
    Ignjatovic, Jelena
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Utredning av projekteringsverktygets ROL utvecklingsbehov: En anpassning för norsk marknad2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Rail Overhead Line (ROL) is a design tool, owned by the company Bentley Systems AB. The design tool is used by overhead line engineers at Sweco Rail to design contact line for electric railway. Sweco Rail intends to establish themselves on the Norwegian market together with their sister company Sweco A/S. Before entry into the new market, a development of ROL is required. The objective with the thesis has been to identify the requirements and the development needs, which are required to adapt ROL against the Norwegian market.The administrations Jernbaneverket and Trafikverket, which are major customers to Sweco, requires more often that Building Information Model (BIM) is to be used in their projects. The goal with the use of BIM is to lead the work to a more efficient management, as well as reduce the risk of information being lost between various stages and processes within the projects. Before entry on the Norwegian market, it is therefore necessary of Sweco Rail and Bentley to adjust ROL in order to be able to deliver 3D-models. The 3D-models have to fulfill the requirements that the Norwegian administration Jernbaneverket demands of the use of BIM in projects.To identify the development needs that are required for a Norwegian adjustment of ROL; interviews, observations and a study of governing documents was performed. Customer needs were identified and translated to requirements. These requirements led to the identified development needs.The result showed that 56 development needs have to be fulfilled before ROL can be used as a design tool on the Norwegian market. The identified development needs include actions with the intention that the design tool can be used in greater extension on the Swedish market. Sweco and their resources can rectify 22 of the 56 development needs. For the remaining 34 development needs, the owners Bentley Systems need to take responsibility for the solutions that is required to satisfy the needs.

  • 49.
    Janssen, Edward
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Concept development of a slat in a core shaft2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A slat in a core shaft is used to lock a core that is placed over it. Five slats in a shaft are pushed outwards to provide friction between core and shaft. The problem is that the slats do not provide enough friction in combination with some core materials. This project aims to solve this problem.

    The problem was studied by looking at the current situation, doing experiments and reading friction theory.

    About thirty concepts were generated by competition analysis, going through the TRIZ databases, doing a patent survey, interviewing, brainstorming and making a combination table.

    Two concepts were selected by screening and selection matrices. One concept is a rubber slat with a different shape than the current one, the other concept a laminate with an aluminum bottom and rubber top.

    Prototypes were made for the rubber slat and they were tested, resulting in a technical drawing. This was used to order several meters of the slat so final testing can be done. A cost analysis was made.

    For the laminate concept, the necessary strength of the aluminum part was calculated and the cost was examined.

  • 50.
    Jansson, Kristoffer
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Utvärdering av lagersystem i däckbranschen: En förstudie utifrån tekniska och ekonomiska aspekter2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background and problem: This study is a feasibility study of a new inventory system that a company in the tire industry has in mind to invest in. The company's inventory is currently full and they are forced to decline customers who want to store their wheels. By investing in a new warehouse system, the storage capacity is expected to increase.

    The company has a proposal for a new storage system, which is used as a base of the study. The specific case will be used as an example throughout the study where general approaches are presented. Furthermore, the result may be used for other types of studies in similar area.

    Purpose: The study evaluate the feasibility of an investment, with the aim of creating an approach that can be used in the evaluation of an investment.

    Method: A qualitative and quantitative feasibility study has been carried out, which is divided into two parts, economic and technical feasibility. The quantitative information is responsible for the economic feasibility of using profitability calculations, while the qualitative part responsible for the technical feasibility of using observational study and questionnaire. Furthermore theory about logistic and inventory management will be used in addition to the technical feasibility. The theory of profitability calculations and logistic have been collected with the help of a literature study.

    Conclusion: The investment in the case is expected to be profitable for the company, both financially and technically. The pay-back period is estimated at six years and three months. The investment is expected to generate positive effects for the workers, because the new warehouse system eliminates the hardest and most time-consuming steps in the warehouse management.

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