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  • 1.
    Abdalameir, Hussein
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Daher, Maher
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Standardization of interfaces for electrical cabinets: How to optimize time saving and cost efficiency for electrical cabinets in submarines2022Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background: In general, it is very complicated to build submarines. There are many parts and equipment that must be in place, and there are tight spaces on the boat. As submarine development progresses and new modern concepts take shape, the installation of new equipment on board becomes more complex, placing higher demands on well-defined interfaces, both geometrically and logically. The approach to electrical cabinets today is to run the cables from the bottom or top through a cable transit system, and only after the cabinet is installed on the submarine can the cables be installed in the proper terminals. This means that the installation takes a lot of time and combined with the fact that there are so many cables sticking out of the cable grommet, the work becomes even more superficial as installers are also constrained by the tight space. Sometimes workers also must move around to make room for others to pass through other parts of the submarine. This means that workers must leave their jobs and move before resuming their work. The following can happen several times a day, which means more time is needed to install electrical cabinets on the submarine.

     

    Purpose: The purpose of this work is to develop and design a solution that is a standardized interface for equipment in the form of electrical cabinets that are present and used in submarines. In this way, the solution must be able to satisfy the different interfaces of the devices that the different subcontractors provide to the company. The created proposals must be illustrated with a CAD software to visualize the concept.

     

    Methodology: The research methodology used in this project is a combination of Participatory Action Research (PAR) and Design Thinking (DT).

     

    Result: The result presents a solution (ISO-box) that shows that it is possible to reduce and optimize the time to install the cabinet once the cabinet is permanently mounted on the submarine. The solution is presented in the form of a CAD model. The model is set up so that all the cables coming from the cable transit system have an adapter at the end, which has a counterpart in a box to the cabinet that is installed on the submarine. Then when the cabinet is assembled, all that must be done is to plug the right connector into the right place in this box. The box has colors for the connectors and numbering that makes it easier for the installer to know which adapter to use.

     

    Conclusions: The work shows that it is quite possible to change the current solution so that less time is needed in the final assembly of the cabinets. It will be easier to just connect the contacts and then leave room for others to pass in the confined spaces. It will also be easier to maintain, as the installer can replace broken contacts as the solution is modular, and there is the possibility of installing new equipment with ISO-box if necessary.

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  • 2.
    Abdulkarim, Abrahim
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Al Outa, Nima Nova
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Conceptualizing an automated sorting system for the recycling of plastic-floors2020Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background

    Tarkett AB Ronneby (Sweden) is a flooring solutions company, recognized for the manufacturing and recycling of homogeneous plastic flooring. Tarkett AB recycles mainly installation spill and manufacturing defects. However, Tarkett AB is considering widening its recycling capabilities to include old and torn plastic floors which may contain impurities and banned substances or plastic floors of competing brands. To accomplish this, Tarkett is considering a completely new recycling line with an automated sorting process instead of the current manual process. Thus, Tarkett proposes a dissertation to conceptualize a new automated sorting system with added capacity and increased functionality.

    Purpose

    This work aims to investigate the current sorting process and introduce conceptual solutions for a new automated sorting process capable of identifying and separating plastic floors according to the manufacturer, type, condition, and external waste by using existing technology.

    Method

    The methods and tools used in this work are mainly based on a modified product development process. Starting with data collection of the current sorting process, performing a need-finding, and extracting requirements for an automated sorting process, investigating relevant technology, evaluating technology based on scientific literature and tests. The testing was conducted in collaboration with two companies. Near-infrared scanners were tested with Holger AB, while pattern recognition systems were tested with Vision-Geek. Finally, three concepts for the automated sorting process were developed and shown through flow charts and 2D-3D illustrations.

    Results

    The results of this work showed that it was possible to use near-infrared and pattern recognition for the separation of plastic floors. Besides, three conceptual solutions for an automated sorting process were generated and showcased with schematic graphs and 2D-3D illustrations. The concepts describe how the sorting process functions and what technology is used for each step of the process. Concept 1 and Concept 2 used both pattern recognition and spectroscopy methods. While Concept 3 only used spectroscopy methods. Moreover, spectroscopy methods were used to sort plastic floors by content while pattern recognition by appearance.

    Conclusions

    Recycling of torn and old plastic flooring can be beneficial for both the environment and the recycling industry. Yet, it presents some challenges relating to reliable, fast, and nondestructive identification for sorting and separation purposes. New and proven technology such as near-infrared hyperspectral imaging and pattern recognition can be used. However, high-quality pattern and spectrum libraries of multiple plastic floors have to be created for optimal and reliable reference models. Furthermore, pattern recognition and near-infrared methods need to be tested further at an industrial scale. 

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  • 3.
    Abid, Usman
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Mustafa, Ghadir
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Effektivisering av arbetsmetod vid framtagning av detaljritningar för produktion och montage inom byggbranschen2021Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    STARKA Betongelement AB is a privately owned company with a focus on manufacturing prefabricated concrete elements. STARKA works with everything from design, manufacturing to the assembly of concrete elements. The process that is mainly studied is their design process, here the different elements are planned to be manufactured and assembled. For the manufacture and assembly, drawings are produced as a basis for this work, these drawings consist of detailed drawings. The creation of these details is currently a time-consuming process; hence, this study aims to develop a more efficient working method that can both make it easier for designers and reduce demanding working hours.

    During the work, the design thinking process is followed as a method when developing the solution. The method consists of four primary phases, starting with understanding the problem that has been given. Furthermore, the area of the problem is studied, through various literature studies, observations, interviews and various tests. After forming a good foundation, different ideas are created to solve the problem. Finally, the final solution is implemented at the company and the implementation was evaluated.

    Results consist of an AutoLISP-program that consists of all the necessary functions under one program, to create the detailed drawings for production. The functions that appear in the program are as follows: measurement of details, in-cast goods measurement, cut line, reinforcement text and “hitsymbol”. Features and their specifications used in the program have been identified through interviews and observations with the engineers at STARKA.

    For assembly drawings, two different solutions have been developed, the first of which tackles engineers' problems in creating complicated details. This is achieved by utilizing the construction’s 3D-model to create the desired detailed drawings. The second solution focuses on generalizing different standard parts and eliminating excess information, such as external dimensions. This in turn creates a better prerequisite for more general details that can be reused in new drawings to save working time.

    s a conclusion for production drawings, the work is facilitated by the program consist of all the necessary functions. Since the features have their pre-inserted specifications, there is no need to configure them afterwards and the insertion becomes correct from the first step. The designers have found the solution helpful and have simplified their work by making “handpåläggning” more efficient and reducing working hours. “Handpåläggning” consist of the functions and methods that the engineers at STARKA use to finalize the drawings. Regarding assembly drawings, the use of 3D-models is considered to be very demanding on computers, but good assistance in complicated details. The standard details make it easier to use standard generalized details to avoid creating and editing new ones for each project. 

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  • 4.
    Abou El Alamien, Karim
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Standard vs. revolutionary sealing:: An investigative thesis on two methods of conceptual designing with regards to the root causes of failure mode in raw mill 7.2020Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The grinding rollers of raw mill 7 operate in very harsh conditions and, because of this, suffer from excessive failure mode due to lip seal deterioration. Foreign material penetrates the deteriorated lip seal and enters the bearings resulting in bearing failure. Failure mode brings about high maintenance costs for the cement-producing company Cementa AB. This thesis aims to accomplish two things. 1- Hypothesize a set of root causes for failure mode and link them to existing literature studies to determine what actions should be taken to prevent or at least postpone failure mode. 2- Generate several new conceptual designs for the sealing mechanism by either creating a revolutionary sealing design or taking inspiration from standard seals currently on the market. The generated concepts aim to provide Cementa AB with a new perspective as well as mitigate some or all the root causes for failure mode if implemented.

    The hypothesized root causes for failure mode are categorized through the creation of a problem tree and are defined as lip seal failure, lubricative pressure and contamination, tribologically improper friction, vibration, and finally very harsh conditions that are indigenous to raw mills in general and that are seemingly incompatible with the current sealing mechanism. Revolutionary concepts are brainstormed entirely from an experimental perspective, while standard concepts are inspired by established sealing technology on the market. Both alternatives are then conceptually adapted to the grinding roller of raw mill 7 and, with inaccurate scaling, 3D modelled with the aid of Autodesk Inventor.

    7 concepts, revolutionary and standard combined, are generated as a result. The revolutionary concepts have been deemed non-viable due to the limited timeframe and scope of the thesis. Instead, the selected seal for the upgrade is a labyrinth seal, which is a non-contact standard seal that has the potential to mitigate many of the root causes for failure mode. The literature studies on the hypothesized root causes also indicate that there are actions that could postpone failure mode should Cementa AB chose to retain the original sealing mechanism for a longer period.

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  • 5.
    Aco, Dekan
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Tillverkningsekonomisk utvärdering av återvinning och återanvändning av blyfri mässing2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This master thesis is part of a larger project (Evochip), conducted at Lund University, faculty of engineering, Industrial Production Department (iProd). The project is in collaboration with AB Markaryds metallarmatur and Mistra innovation. In this work, a dynamic cost model has been developed to calculate the manufacturing costs of components made from recycled chips of lead-free brass from the manufacturing processes of AB Markaryds metallarmatur (MMA).

    In the current situation, all rejected details and waste materials are sent to the material supplier in southern Europe for recycling. The transport takes place by trucks and the recycling process is based on an energy-intensive melting step. Development projects are currently underway to reuse the chips without melting at sight at MMA´s facilities, but the cost per detail has been unknown for the company. With the help of this thesis, the manufacturing price will be presented. The manufacturing process is divided into a total of 11 different processing stations. To estimate the costs, Jan-Eric Ståhl's dynamic cost model is used. Necessary data and information have been collected using interviews with the employees of the company and through the company's own documentation regarding the production lines. In order to reduce the error margin in the results, suitable Monte Carlo simulations have been performed.

    The work is also based on a sustainability perspective. In addition to eliminating transportations by trucks and energy-intensive melting processes for the products, the work also promotes the use and reuse of lead-free brass by pressing metal chips to form new bars. All this in order to avoid leaded brass components due to the negative health effects caused by the lead.

    The component investigated in this work is a radiator valve called EVO 10. The valve is found in the company's lead-free standard range. The cost model in this project is dynamic to the extent that it could be applied in the future to other lead-free brass components at MMA.

    A comparison of two different concepts is presented in the results section. Concept one represents the current manufacturing system, and concept two, the future compacting technology. Since many of the processing steps are the same for both systems, a comparison was made between the productions of the pellet through the two different concepts. The results show that pellets made according to today's manufacturing system cost 12.75 SEK / detail, and pellets manufactured according to concept two costs 9.61 SEK / detail.

    As concept two is dependent on chips from today's manufacturing system, MMA cannot completely switch to compacting chips to new pellets. More work must be done to find a balanced model between the two different manufacturing systems for the best possible results.The results from the Monte Carlo-simulations shows that the manufacturing cost with the chosen parameters and variables is 12.96 SEK/detail.

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  • 6.
    Adnan, Md Asif
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Shehata, Ahmed
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Stress Analysis Validation for Gear Design2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Gear stress analysis and understanding the effect of misalignment and microgeometry is important for gear designers and for those who work in gear maintenance. The misalignment can lead to the higher stress acting in one side of the gear tooth and the micro-geometry modification can improve the stress distribution in the gear teeth. In this research, a helical gear pair was modeled using three different software and tools; LDP, KISSsoft and Abaqus. Three different cases were modeled to study the effect of misalignment and microgeometry. Finally, the results from different tools were presented and discussed. It was observed that the tooth contact analysis software resulted in significantly higher stresses than the FE software. The results have been discussed to understand the differences in the cases obtained from the used tools. The results showed how bad is the effect of the misalignment on the gear mesh and the stress distribution and how the microgeometry modifications are used to compensate that effect.

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    BTH2018Adnan
  • 7.
    Adolfsson, Erika
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Automatiseringskonstruktion till mätfixtur2019Independent thesis Basic level (university diploma), 12 credits / 18 HE creditsStudent thesis
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    BTH2019Adolfsson
  • 8.
    Aeddula, Omsri
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Data-Driven Decision Support Systems for Product Development - A Data Exploration Study Using Machine Learning2021Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Modern product development is a complex chain of events and decisions. The ongoing digital transformation of society, increasing demands in innovative solutions puts pressure on organizations to maintain, or increase competitiveness. As a consequence, a major challenge in the product development is the search for information, analysis, and the build of knowledge. This is even more challenging when the design element comprises complex structural hierarchy and limited data generation capabilities. This challenge is even more pronounced in the conceptual stage of product development where information is scarce, vague, and potentially conflicting. The ability to conduct exploration of high-level useful information using a machine learning approach in the conceptual design stage would hence enhance be of importance to support the design decision-makers, where the decisions made at this stage impact the success of overall product development process.

    The thesis aims to investigate the conceptual stage of product development, proposing methods and tools in order to support the decision-making process by the building of data-driven decision support systems. The study highlights how the data can be utilized and visualized to extract useful information in design exploration studies at the conceptual stage of product development. The ability to build data-driven decision support systems in the early phases facilitates more informed decisions.

    The thesis presents initial descriptive study findings from the empirical studies, showing the capabilities of the machine learning approaches in extracting useful information, and building data-driven decision support systems. The thesis initially describes how the linear regression model and artificial neural networks extract useful information in design exploration, providing support for the decision-makers to understand the consequences of the design choices through cause-and-effect relationships on a detailed level. Furthermore, the presented approach also provides input to a novel visualization construct intended to enhance comprehensibility within cross-functional design teams. The thesis further studies how the data can be augmented and analyzed to extract the necessary information from an existing design element to support the decision-making process in an oral healthcare context.

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  • 9.
    Aeddula, Omsri
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Flyborg, Johan
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    Larsson, Tobias
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Anderberg, Peter
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    Sanmartin Berglund, Johan
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    Renvert, Stefan
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health. Kristianstad University, SWE.
    A Solution with Bluetooth Low Energy Technology to Support Oral Healthcare Decisions for improving Oral Hygiene2021In: ACM International Conference Proceeding Series, Association for Computing Machinery (ACM), 2021, Vol. 1, p. 134-139Conference paper (Refereed)
    Abstract [en]

    The advent of powered toothbrushes and associated mobile health applications provides an opportunity to collect and monitor the data, however collecting reliable and standardized data from large populations has been associated with efforts from the participants and researchers. Finding a way to collect data autonomously and without the need for cooperation imparts the potential to build large knowledge banks. A solution with Bluetooth low energy technology is designed to pair a powered toothbrush with a single-core processor to collect raw data in a real-time scenario, eliminating the manual transfer of powered toothbrush data with mobile health applications. Associating powered toothbrush with a single-core processor is believed to provide reliable and comprehensible data of toothbrush use and propensities can be a guide to improve individual exhortation and general plans on oral hygiene quantifies that can prompt improved oral wellbeing. The method makes a case for an expanded chance to plan assistant capacities to protect or improve factors that influence oral wellbeing in individuals with mild cognitive impairment. The proposed framework assists with determining various parameters, which makes it adaptable and conceivable to execute in various oral care contexts 

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    ICMHI-OKA
  • 10.
    Aeddula, Omsri
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Gertsovich, Irina
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mathematics and Natural Sciences.
    Image-Based Localization System2020In: Proceedings of the 8th ICIECE 2019, Springer , 2020, Vol. 107, p. 535-541Conference paper (Refereed)
    Abstract [en]

    The position of a vehicle is essential for navigation of the vehicle along the desired path without a human interference. A good positioning system should have both good positioning accuracy and reliability. Global Positioning System (GPS) employed for navigation in a vehicle may lose significant power due to signal attenuation caused by construction buildings or other obstacles. In this paper, a novel real-time indoor positioning system using a static camera is presented. The proposed positioning system exploits gradient information evaluated on the camera video stream to recognize the contours of the vehicle. Subsequently, the mass center of the vehicle contour is used for simultaneous localization of the vehicle. This solution minimizes the design and computational complexity of the positioning system. The experimental evaluation of the proposed approach has demonstrated the positioned accuracy of 92.26%. © Springer Nature Singapore Pte Ltd. 2020.

  • 11.
    Aeddula, Omsri
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Wall, Johan
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Larsson, Tobias
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    ARTIFICIAL NEURAL NETWORKS SUPPORTING CAUSE AND EFFECT STUDIES IN PRODUCT-SERVICE SYSTEM DEVELOPMENT2021In: Design for Tomorrow—Volume 1: Proceedings of ICoRD 2021 / [ed] Chakrabarti, A., Poovaiah, R., Bokil, P., Kant, V. (Eds.), Springer, 2021, Vol. I, article id 132Conference paper (Refereed)
    Abstract [en]

    A data analysis method based on artificial neural networks aiming to support cause-and-effect analysis in design exploration studies is presented. The method clusters and aggregates the effects of multiple design variables based on the structural hierarchy of the evaluated system. The proposed method is exemplified in a case study showing that the predictive capability of the created, clustered, a dataset is comparable to the original, unmodified, one. The proposed method is evaluated using coefficient-of-determination, root mean square error, average relative error, and mean square error. Data analysis approach with artificial neural networks is believed to significantly improve the comprehensibility of the evaluated cause-and-effect relationships studying PSS concepts in a cross-functional team and thereby assisting the difficult and resource-demanding negotiations process at the conceptual stage of the design.

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    ICORD_21
  • 12.
    Ahlin, Simon
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Återbrukande - kron- & rustikljusstake2022Independent thesis Basic level (professional degree), 5 credits / 7,5 HE creditsStudent thesis
  • 13.
    Ahmad, Abu ul Hasnat
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Review of Earlier Thesis work at BTH Related to Packaging and Packaging Field2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This work aims at giving a systematic review of the numerical approaches and obtained results published in recent years. Focus is set on both the recent trends and achievements as well as challenges and open questions. Thesis critically reviews work done in previous thesis related to food packaging material and design, at Blekinge Institute of Technology with the collaboration of Tetra Pak liquid food packaging company. Here, 27 numbers of master’s thesis are critical review all the while using 4 PHD works for referencing.

     Focus of these thesis works relates to the mechanics and its sub-branch fracture mechanics. Due to this all the theory related to mechanics and fracture mechanics, which is compulsory to know for understanding is defined initially. Main material which are under consideration throughout the work are PP, LDPE, PET-LDPE, and aluminum foil. As three materials are used in the liquid food packaging which are PE, paper board and aluminum. Uses of this material and there required physical properties are measured. Testing methods which are used to check whether the material meets the required parameters are tensile testing, tear testing, peel testing and shear test.

     Also, some methods are used along with these tests to perform the test more precisely, to evaluate and compare result i.e., Nakajima test, Digital image correlation. DIC testing technique is used to compare the results obtained from simulation. It is also understood that DIC method provided the user with increased quality of obtained results.

     Most of the topics of discussions have been reviewed for corresponding thesis, displaying the used ideas, theory, applied experimentation and realized conclusions. Using these above it was able to derive a conclusion based on the developed research questions and hypothesis. Defined problems in previous work are studied also solution as a future work is suggested to overcome these problems. Mainly the slippage issue while holding PE in clamps. Furthermore, various development is discussed which is done to introduce new material which is more possible being used in the future.

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  • 14.
    Aisvaran, Chandramohan
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Study of non-linear strain path in sheet metal forming2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    At present, Sheet Metal Forming (SMF) is not just limited to increasing demand from automobile industries but also to various other manufacturing industries that utilize sheet metal forming processes. The surplus demands for optimised manufacturing products warrant the need for an extended decisive study on SMF. 

    One such area of study in SMF is formability. Traditionally, formability is predicted using the conventional Forming Limit Curve (FLC). But when it comes to complex SMF processes, FLC failure model can sometimes overestimate (for low uniaxial straining) or underestimate (for bi-axial straining) failure. This thesis focuses on suitable test procedures to generate non-linear strain paths and prediction of formability using the concept of Generalized Forming Limit Curve (GFLC). Initially, through systematic literature review, two-step process is chosen as the test procedure in this thesis. The test procedure was simulated in LS-Dyna to obtain results which are then used by GFLC concept to predict formability for a bi-linear deformation history. The predicted formability using the concept of GFLC is then compared with the predicted formability using FE-simulation and using experimentation.  The found percent error for GFLC prediction compared to that of FE-simulation prediction is 11% and the percent error for GFLC prediction and experimentation prediction is 14%. However, these two predictions can not be used to validate the GFLC prediction. This is because in this thesis GFLC procedure uses data obtained from FE-simulation with GISSMO failure model. Through literature, it is identified that the GFLC concept can be applied for multi-linear deformation histories to predict formability and the method to do so is explained in detail in this thesis. Finally, it is concluded that the use of the GFLC concept in conjunction with the two-step drawing process to predict formability for bi-linear deformation history is acceptable.

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  • 15.
    Akulavicius, Milvydas
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Lamellgardiner2020Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
  • 16.
    Akurati, Parthasri
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Kumar, Karan
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Development of a 3D Ring Dynamics Model For a Heavy-Duty Piston Ring-Pack2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    With the increasing restrictions in emission legislations, the automotive industry aims to improve the efficiency of the lubricating system and to decrease fuel consumption. In the power cylinder unit (PCU), the piston rings are the major contributor to these consumptions. Hence, focus on the dynamic behaviour of the rings to reduce lube oil consumption (LOC) becomes a key factor in thriving towards sustainability. Several studies have been conducted on the piston ring-pack specifically using a 2D ring dynamics approach. This study focuses on developing a 3D ring dynamics model, in the software tool AVL EXCITE™ Piston&Rings, which is capable of observing the behaviour of the ring along the third dimension i.e. circumferential direction. A coordinated approach used in the methodology gives an insight into the parameters affecting the model behaviour. Within the PCU, wear on the cylinder liner surface and in the piston ring grooves can lead to accelerated LOC. This study further focuses on using the 3D model to analyse the friction and wear on the piston rings. Factors contributing towards LOC are individually studied and the results obtained are compared to the experimental engine test data. The outcome of the 3D numerical model developed shows promising results. The model can therefore be used to simulate different piston ring-packs and analyse the behaviour of the piston ring with a better prediction of friction, wear and LOC. Thus, the model will contribute to reducing the number of physical tests conducted, the expense involved in conducting those tests and would provide satisfactory products to the customer and would manage future emission requirements.

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    Development of a 3D Ring Dynamics Model For a Heavy-Duty Piston Ring-Pack
  • 17.
    Al Choueyri, Yousef
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Fayazi, Mojtaba
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Digital models of manufacturing: with emphasis on titanium welding for early product development2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis work is part of the BTH research lab, focusing on developing the early product development, by analyzing how to integrate the manufacturing process with the early design process. A known problem in the manufacturing industry is the knowledge gap between the designers and the manufacturing process. Where in the early stages of the product development a knowledge regarding the manufacture process is needed. This is in many cases ignored by the designers because it is commonly thought that the responsibility of selecting the manufacturing processes for a product falls upon the manufacturers, despite the fact that the manufacturing processes in reality is highly dependent upon the design choses such as materials, size, shape, finishing and tolerances of the product. To mitigate this problem a variations of product ‘team’ approaches have been used where the idea is to involve a multitude of people with the necessary experience to produce a ‘production friendly product’. Those approaches have a few drawbacks mainly the problem of finding people with the relevant experiences or that the expertise only covers the manufacturing processes already used in the organization, losing the opportunity to benefit from any alternative manufacturing process.

    This thesis focuses on how the welding manufacturing technic, analysis can be integrated into the design process with the help of a digital model?

    To improve the communications between the manufacturers and designers, two excel files were developed. The first excel file aimed at the manufacturers where they can present the specific machines used in the workshop. Focusing on specific machine and workshops instead of on the general welding method will give the designers a better understanding of the feasibility of producing their design in a specific workshop instead of focusing on a specific manufacturing method.

    The second excel file is aimed at calculating and comparing the weld methods where the cost and requirements are derived for general welding methods and compared with the machine specifications gathered from the manufacturers using the first excel file. To assess the excel files, a parametrized CAD model of the rear engine turbine structure was developed, and three different cases were used to evaluate the developed excel files.

    The values used are presented in Appendix A: Table 11–15, and were gathered from public sources. Values were also approximated using regression analysis.

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  • 18.
    ALAMSETTY, SREETEJA
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    VEMURI, SAITEJA
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Springback Analysis of Aluminium Alloy 2024 in Flex-forming Process2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 19.
    ALFEKY, AHMED
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Analys och korrelation av data från värmekamera2020Independent thesis Basic level (degree of Bachelor), 12 credits / 18 HE creditsStudent thesis
    Abstract [en]

    The thesis is about seeing if there is any correlation between temperature deviation and selected variables to increase the understanding of what affects the camera. The work is an improvement method where R programs are used for mathematical solutions. 

    The methods used for this include data collection and scientific research. Based on the collected input data, the result could be obtained using these methods. An additional method was to connect two or more substances such as statistics and programming in a work where prior knowledge is used, the result is verified and the acquisition of knowledge continues. 

    The purpose was to use prior knowledge and software to see if there is any connection between input data that is on company’s database. The correlation between different variables is something that is used daily in society, industry and the international conventions. The correlation between two variables shows the extent to which they are related. 

    The result was obtained in the form of calculations, graphs and tables. There are indications that there is a weak correlation between camera angle and temperature deviation while there is a mean correlation between position and temperature deviation. There is a very weak correlation between holding times and temperature deviation, something that needs to be verified with several measuring points. 

    There are no definite results due to various factors such as the number of measuring points, although there are some indications that all camera angles except 25 ̊ can be a solution by performing several number of measuring points at both angles. The indication is largest for position in the camera's field of view. As for holding time, there is an indication that it does not affect the camera, but more measurements are needed to verify that indication. 

    The spread is also interesting. If the distribution is reasonably equal in the different cases, the position of the temperature deviation can always be adjusted with the aid of the emissivity.

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    Analys och korrelation av data från värmekamera
  • 20.
    Ali, Mazin
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Shahin, Mahdi
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Framtagning av kalibreringsverktyg för referensmätningar: Vardaglig kontroll av kalibrering i industriell provbänk för pneumatiskt styrda tågbromsar2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Faiveley Transport Nordic AB is a company in Landskrona and which is an international supplier in the railway industry. The industry sight in landskrona is mostly focused on developing and manufacturing train brakes.Today, Faiveley has a number of test benches that needs regular checks and re-calibration every three months. In the current situation, it is the responsibility of the lab engineer to check that the calibration is correct on the test benches and adjust if needed. The purpose of this research is to design a reference object that will be used for checking the calibration on a test bench.During the research, the product development process was used with some tools from the design thinking process. The research begins with a lot of theoretical background about BFC (Brake Friction Concept), test benches and calibration to develop a deeper understanding for the different concepts.Since Faiveley had already identified the problem, the method was started directly by looking for other solutions that could inspire the solution to the problem. The search for inspiration was conducted through various methods such as patent searching, trend watching and techwatching. The authors proceeded by choosing the best possible ideas for them to create a prototype of the best concepts.After creating a prototype of the reference object, the objects function was verified by testing on a test bench to check if it meets the preset requirements. The authors were able to get the result for each one of them three measurement parameters such as force, distance and pressure. Results showed that most of the requirements was accomplished.Based on the results several conclusions could be drawn. Such as that the reference object that was the solution to the problem worked and partly fulfills the associated requirements. Through this research a method has been created for how to generate reference values for similar parameters in general contexts, which others interested can use in the future.

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  • 21.
    Aljafari, Mohammed
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Support for autonomously driven systems in harsh environments.: Degree project for Master of Science in mechanical engineering with focus on innovation and sustainable product development2023Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Symptoms of harsh environments create pressure on autonomous machines to work wellwith the use of measurement devices. Sensors used within construction equipment vehiclessuffer from being covered with fogs of dirt, oil, water, and dust. Autonomous vehicle’sdependency on fully functional sensors paves roads for research to be made on ways to keepsensor data from being compromised and automation to be improved.In cooperation with Dynapac Compaction Equipment AB, this master’s thesis problemopted for innovative and sustainable product development to tackle the problem. The thesiscomprises of 30 credits. In this thesis, work will be done emphasizing on ways to keepautonomous performance at peak for construction equipment vehicles with low to no capacityfor sophisticated equipment and supply of power and water. For reference, the project targetsasphalt rollers due to their relevance at Dynapac.With the use of innovative product development tools, the problem is to be tackled with anengineering approach revolving around the design thinking process. All progress will beconstituted at Dynapac’s facilities in Karlskrona. Interviews and dialogue with relevantindividuals are to be held to create value based on customer needs which has been of highpriority and is to be iteratively monitored throughout the project. Prototyping will play a partwith large amount of testing to prove concept, including processes of 3dmodeling andmanufacturing of components.With measurement incorrections reaching up to 80 degrees out of a measurement spanwithin the range of 0 to 150 degrees, three concepts have been established, each of which areequipment neutral to benefit construction vehicles which has shown to be valuable within theindustry.A pipe concept which’s purpose is to hide the sensor further and create distance betweensensor lens and measurement surface has been established. The concept is feasible for theconstruction industry, protects the sensor from debris and supports autonomous systems.

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  • 22.
    Alkhalili, Ahmad
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Effektivisering av reservdelsutvärdering inom fordonsindustrin2023Independent thesis Basic level (university diploma), 12 credits / 18 HE creditsStudent thesis
    Abstract [en]

    This thesis has been done during the spring term 2023 in the company Scania

    in Södertälje, Stockholm. The degree project is about streamlining spare parts

    management in the automotive industry by using Lean principles, Scania

    production system and spare parts classification. The work is an improvement

    project where the spare parts produced on the e-mobility production line and

    this is the focus of the work.

    The work began by collecting data through interviews, observations, and the

    company's production system. Next, the current state of production was studied,

    where production volumes were followed up and linked to appropriate

    classification methods, then value flow mapping was created for the current

    state.

    The results obtained from the current situation description, production process

    and production analysis showed that the company works based on its principles

    and priorities, spare parts classification, and largely applies the lean principles.

    The degree project involves carrying out an improvement project that is not

    only about analyzing and investigating the problems, but it focuses on

    identifying relevant methods and solutions that can be implemented. Finally, a

    conclusion is done, and suggestions are made as to whether the solution and

    method can contribute to improvement. The conclusions suggest that the

    company focuses on the most demanded spare parts and manufacture them on

    the dedicated production line for the next two years, which is a proven way of

    working that proves to be suitable and effective as it is used and works well in

    other production lines within the same company.

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    Effektivisering av reservdelsutvärdering inom fordonsindustrin
  • 23.
    Allesson, Sara
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Sheet Metal Forming Simulations with Elastic Dies: Emphasis on Computational Cost2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The car industry produces many of their car parts by using sheet metal forming, where one of the most time-consuming phases is the development and manufacturing of new forming tools. As of today, when a new tool is to be evaluated in terms of usability, a forming simulation is conducted to predict possible failures before manufacturing. The assumption is then that the tools are rigid, and the only deformable part is the sheet metal itself. This is however not the case, since the tools also deform during the forming process. A previous research, which is the basis of this thesis, included a model with only elastic tools and showed results of high accuracy in comparison to using a rigid setup. However, this simulation is not optimal to implement for a daily based usage, since it requires high computational power and has a long simulation time. 

    The aim and scope for this thesis is to evaluate how a sheet metal forming simulation with elastic tool consideration can be reduced in terms of computational cost, by using the software LS-DYNA. A small deviation of the forming result is acceptable and the aim is to run the simulation with a 50-75 % reduction of time on fewer cores than the approximate 14 hours and 800 CPUs that the simulation requires today.

    The first step was to alter the geometry of the tools and evaluate the impact on the deformations of the blank. The elastic solid parts that only has small deformations are deleted and replaced by rigid surfaces, making the model partly elastic. Later, different decomposition methods are studied to determine what kind that makes the simulation run faster. At last, a scaling analysis is conducted to determine the range of computational power that is to be used to run the simulations as efficient as possible, and what part of the simulation that is affecting the simulation time the most.

    The correlation of major strain deviation between a fully elastic model and a partly elastic model showed results of high accuracy, as well as comparison with production measurements of a formed blank. The computational time is reduced by over 90 % when using approximately 65 % of the initial computational power. If the simulations are run with even less number of cores, 10 % of the initial number of CPUs, the simulation time is reduced by over 70 %.

    The conclusion of this work is that it is possible to run a partly elastic sheet metal forming simulation much more efficient than using a fully elastic model, without reliability problems of the forming results. This by reducing the number of elements, evaluate the decomposition method and by conducting a scaling analysis to evaluate the efficiency of computational power.

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  • 24.
    Al-Shuwaili, Mustafa
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Helo, Zeid
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science.
    Optimering av interna materialflödet på Scandinavian Stone2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The thesis focuses on analysis and development of a material flow on a quarry, which belongs to the company Scandinavian Stone. A material flow that is dependent on heavy vehicles, which causes high costs and carbon dioxide emissions. The company strives for a development that focuses on carbon dioxide emissions - and cost reduction. The process was examined in several activities, such as study visits, interviews and observations. A survey is the basis for a process analysis that takes to the surface development needs and shortage factors. The analysis was based on the Lean philosophy, to distinguish between value-adding and non-value-adding parameters from a customer perspective. The results of the analysis showed that the distance between the lowest point in the hole to the processing station, is the part that contributes the highest energy consumption. A calculation model has been created to be able to calculate the energy consumption that is resulted from product transports within the process. The calculation was made on a simplified driving cycle with varied product weights. The results from the calculation model showed that an increase in product weight leads to small energy increases. This was the basis for a concept that focuses on a reduction in the number of runs along the identified route. To maintain process productivity, it is necessary to transport several products and heavier waste materials at a time. The proposed concept changes the layout of the process, as the processing station is moved down to the hole, instead of its current location outside the hole. It enables the transport of several products at a time, as the products lose about 50% of their weight after processing. The waste material is temporarily stored in a container and then transported up when the weight has reached a maximum level. This maximum weight is observed by means of a scale on which the container is placed. The scale indicates when that limit has been reached and it is time for emptying. The concept showed a profitability in energy consumption of up to 40%.

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  • 25.
    Ameen, Noor
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Safawizadeh, Hassan
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Visualizing Material on Site for Machines and Humans: A Step toward an Autonomous Construction Site2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The construction industry has not seen the same growth in productivity as e.g. the manufacturing- and automobile industry. This is largely due to the ease of implementing automation and robotics in the latter mentioned industries. Now more than before when the urbanization rate is increasing, there is a strong need in increasing the efficiency of the construction industry. That is why the research questions of this thesis work involves finding a complementary solution that will help autonomous construction machines operate in a dynamic construction site. The aim is permeated by two visions. The first one being to have autonomous construction machines collaborating with humans in the most remote places in the world. The second vision is that multiple smaller construction machines is more beneficial. Meaning a few machine breakdowns would not halt the entire construction process.

    During the research work, using the design research methodology and the innovation process, data showed that a construction site is very dynamic and complex. Having a change in factors such as size of construction site, number of involved stakeholders, location of the construction site, and time phase heavily affects the complexity of the site. Throughout the three case studies there were different characteristics, but there was a pattern. All the mentioned factors played a huge role in what needs expressed by the interviewees. The more complex a site was, the more there was a need to organize the material, personnel and machine flow. Therefore, the final solution is to decentralize the information flow of the construction site. Meaning that all humans, machines and material on site is to communicate its information. The suggested solution is the usage of a tag using GPS and Wi-Fi to communicate location and the necessary information. Thus, when attaching the tag onto a material, the workers and the machine will know of its information.

    The analogy is that when the implementation of autonomous machines is up to pace, the sites need to be prepared with all the errors and issues that might come with it. Since the autonomous construction machines will be collaborating with humans, it means that the issues expressed today will reappear in the future. Also, since the implementation of autonomy and robotics has been slow for the construction industry, there is a clear need of a complementary solution to speed up the process. By decentralizing the construction site and implementing tags on each interesting point, the once complex and changing construction site, will turn into a fully digitized infrastructure.

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    VisualizingMaterialOnSite
  • 26.
    An, Hai
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Gu, Lujun
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Main Success Factors for Developing Car-sharing in China2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
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  • 27.
    Andersson, Andreas
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Measuring the contact pressure during sheet metal forming of automotive components2020Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The competition in the car market in the world is continuously intensifying. To gain an advantage in the market while making a profit, each car manufacturer needs a strong focus on always improving in the technology development. It is not just technology of the cars that need development, but it is equally important to improve the manufacturing processes itself. In the end, this will result in more appealing products for the customer at a competitive cost.

    The aim and scope of this master thesis is to get a deeper understanding of the forces in the stamping die during sheet metal forming in manufacturing. By using strain gauges and microcontrollers, the forces during the entire forming process could be measured and analyzed. The relationship between the force on the pressure pins in the die and the length of the pressure pins was also investigated by adding shims on the pressure pins.

    A modular system using Arduino Uno with 3D-printed parts was developed to measure the forces in the blank holder during sheet metal forming. An Arduino software system and TeraTerm was found the most appropriate for collecting and organizing data from the strain gauge sensors and microcontrollers. Tests were then conducted using different settings of the press, and these showed that the forces in the blank holder were uneven. Adding shims to the pins so that they were all of equal length evened out the forces in the blank holder. Another test showed that adding more shims to only one of the pins increased the force in that pin, and that adding 0.5mm of shims to that pin more than doubled the maximum force.

    The system developed in this thesis can measure the forces in the blank holder during the sheet forming process at a lower speed of production. This system can also detect different force settings in the press. Lastly, it can also detect a difference in force for different pressure pin lengths.

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  • 28.
    Andersson, Carolina
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Fritidsbåt för alla2015Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [sv]

    Ett fysiskt handikapp kan innebära stora begränsningar i livet. För de som sitter i rullstol kan det vara mycket svårt eller till och med omöjligt att förflytta sig dit de vill och få uppleva aktiviteter som personer utan handikapp tar för givet. Det här kandidatarbetet har haft som syfte att ta fram en handikappanordning som ska göra det möjligt för rullstolsburna att kunna ta sig ombord och iland från fritidsbåtar. Det finns redan olika lösningar på marknaden som syftar till att möjliggöra en sådan förflyttning, men målet med det här arbetet har varit att ta fram en lösning som är annorlunda jämfört med de befintliga lösningarna framförallt vad gäller möjligheten till att använda den från båten istället för från kaj, samt att den ska kunna installeras till en rimlig kostnad och dess design ska passa flertalet fritidsbåtar utan alltför stora krav på båtens utformning. 

    Det viktigaste kravet på produkten är att den ska vara säker att använda. Det får inte föreligga någon risk för personskada. Andra krav som ställdes upp när problembeskrivningen arbetades fram är att anordningen ska vara enkel att använda. Installationen ska vara möjlig att göra i flertalet fritidsbåtar till en rimlig kostnad. Detta för att ett plötsligt behov av rullstolsanpassning inte nödvändigtvis ska behöva innebära inköp av en ny båt. Produkten ska vara hållbar (kunna vara monterad och användas under många år) och inte kräva service under den primära utnyttjandeperioden (under sommaren). Under utvecklingen togs hänsyn till miljöaspekter i val av tillverkningsmetoder och materialval. 

    Det slutliga produktförslaget, som arbetats fram efter att ha gjort flertalet analyser och utvärderingar av på marknaden befintliga lösningar, är en mast som monteras i durken på båten. Masten har ett stödben som placeras på bryggan/kaj, vilket ger stabilitet och därmed hög säkerhet för användaren. Detta då motorbåtar inte har en köl som kan fungera som motvikt för den sidobelastning som ombordstigningen innebär. 

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  • 29.
    Andersson, Isac
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Utveckling av beräkningsmalltill ramar belastade med rör2022Independent thesis Basic level (degree of Bachelor), 12 credits / 18 HE creditsStudent thesis
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    Utveckling av beräkningsmall till ramar belastade med rör
  • 30.
    Andersson, Johan
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Andersson, Peter
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Konceptlösning för upptagning av kabel ur karusell2019Independent thesis Basic level (degree of Bachelor), 12 credits / 18 HE creditsStudent thesis
    Abstract [en]

    In collaboration with Semcon Karlskrona, a conceptual solution regarding withdrawal of cable from a carousel was developed. The diameter of the cable were 300 mm and its weight were 160 kg/m. By brainstorming, a number of draft was conceived whereof one were chosen by Pugh's concept screening.

    The solution was an arm supported by a framework construction. The end of the arm is bent to match the minimum bending radius of the cable. The arm is capable to translate sideways by a puck located in runners. These runners are coated by the plastic material Robalon to achieve a good sliding surface. The translation will be made possible by using a wire and a a winch. At the back edge of the arm a hinge were attached, allowing rotation around the supporting pillar. At the centre och the carousel, an axis is located which will be used to fasten the centre pillar against.

    All of the bars that are used in the construction are hotrolled rectangular hollow sections as these are seen to be advatageuos from a manufacturing perspective. The dimensions of the construction was determined regarding buckling, compression, tension and shear. As were the welded and screwed joints.

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    Konceptlösning för upptagning av kabel ur karusell
  • 31.
    Andersson, Karl-Henrik
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Liedman, Stefan
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Off-grid portable production and distribution of sustainable energy: A product service system solution developed for the energy market2022Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background. At the year of 2021, 770 million people worldwide were living without access to electricity. In parallel with this, electrification of vehicles and other equipment constantly increases which results in a demand for access to reliable off-grid energy to allow for operation in remote locations or places without sufficient energy infrastructure due to external factors such as natural disasters. As the use of fossil fuels is predicted to decrease, the need for sustainable energy production utilizing renewable energy sources has proved to be critical. The combination of these factors results in a need for the development of sustainable off-grid energy systems utilizing renewable energy sources. 

    Objectives. The objective of this thesis is to highlight needs and present a developed solution to portable off-grid energy production and distribution utilizing renewable energy sources. The goal is to highlight problems within the area of focus and present a potential solution to one, or multiple, of these problems. The presented solution shall be based on a solid engineering foundation and meet the technical requirements developed from needs that arise during the project.

    Methods. The work presented in this thesis was conducted with the use of DRM, Design Research Methodology, as the choice of research methodology while Design thinking was the choice of design approach. The use of DRM allowed for a structured and efficient research process that allowed for the possibility to validate result. The use of Design thinking as design approach provided methods and tools to support innovation while working with problems that were initially unknown or vaguely defined.

    Results. The result of the work presented in this thesis provides information regarding multiple problems and critical aspects within the area of focus. A list of requirements for a sustainable energy system to satisfy in order to enter the market is presented, where portability, reliability and redundancy are marked as key requirements. A proposed solution in the form of a portable modular sustainable energy production trailer utilizing different renewable energy sources was developed to allow for off-grid electricity generation. This combined with an energy distribution solution in the form of a energy storage module mounted on the Volvo TA15 system allows for autonomous energy transportation to the location of the energy need. 

    Conclusions. As the need for sustainable energy constantly increases, development of sustainable energy production and distribution systems that can operate off-grid has proven to be critical. The utilization of renewable energy sources has also been identified as a critical factor in parallel with the phasing out of fossil fuels. The proposed solution has provided evidence of the potential for a portable off-grid hybrid energy system and its potential impact on the global 2030-agenda goals for sustainability. 

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  • 32.
    Andersson, Mattias
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Sildén, Daniel
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Vidareutveckling av parkeringsbroms2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis report is the final work and summary for Bachelor of Science degree in Product Development. The program has emphasis in Mechanical Engineering, at Blekinge Institute of Technology, 2016.

    This assignment consists of a continued research and development study of a conceptual brake caliper operated by an electric servo-assisted motor.

    In the current situation there is a concept both as a CAD model and a 3D-printed physical plastic model of a parking brake. After a prolonged investigation seems to have brake for large physical dimensions, high weight, as well as for complex surface geometry. Another important part is that you do not in the current situation have found a suitable electric motor for the linear movement required for functionality to be maintained. Which led to the desire to explore the opportunities that exist to improve these points.

    The assignment has led to a series of improvements through further development based on the earlier concept proposal which found new solution proposals and component taking into account the comments they had regarding previous design and technical solutions. These design improvements have very little or no negative impact of previously established requirements and requests for the product, which has been seen as very positive.

  • 33.
    Andersson, Oscar
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Lu, Anqi
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Elektriskt drivsystem för tandemvält: En utvecklingsprocess2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    I dagens samhälle har det blivit mer och mer populärt med miljövänliga lösningar. Inom detta område har fordonsindustrin utmärkt sig de senaste åren genom utvecklandet av eldrivna bilar. Därför börjar även företagen som utvecklar tunga maskiner bli intresserade av att börja utveckla mer miljövänliga produkter.

     

    Syftet med arbetet som vi utfört i samarbete med Dynapac Compaction Equipment AB i Karlskrona har varit att utveckla ett koncept till en lösning av ett miljövänligt drivsystem för deras minsta tandemvält. Det är tänkt att motsvara den vardagliga prestationen av det dieseldrivna systemet, utan att bli för dyrt, samt undvika att använda specialbeställda produkter.

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  • 34.
    Andersson, Oscar
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Wiklund, Alexander
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Strain rate-dependent mechanical properties of high-density polyethylene(HDPE)2022Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In today’s packaging industry HDPE is widely used and correct understanding of itsproperties and how to model them is of vital importance. HDPE is a semi-crystallinepolymer with a known strain rate dependence, that is a higher yield and lower strainto failure at higher strain rates. HDPE does also exhibit the phenomena of cold-drawing, together with other polymers. Cold-drawing is where after the specimenhas necked, the necking stabilizes and starts to pull material above and below intothe neck, effectively elongating the neck while maintaining its width.

    The objective of the study is to look at the local strain rates as the specimen necksand if a simple Abaqus model can capture those effects. The effect of strain rate onthe shape of the neck was also studied.

    The work was to test HDPE in uniaxial tension with different strain rates (∼10-3 s-1to ∼10-1 s-1) and measure the local strain rates with 2D-DIC. A decent amount oftime was used to make sure the camera setup gave the best quality possible for theequipment available. The videos produced was used for the DIC analysis as well asfor the image analysis to measure the width of the neck. After the tests a calibrationscheme was used to create a material model that matched the force-displacementfrom the physical 100 mm/min test data.

    Studying the force displacement the strain rate effects noted in previous researchare present. The results from the DIC show a very high local strain rate as the spec-imen necks, between 11-65 times higher than the global (grip-to-grip) strain rate.From the measurement of the width there are some rate effects as well. The slowerspeeds (5 and 10 mm/min) shows a continually reducing width while the 50 and 100mm/min shows a more stable neck and the 500 mm/min test does not have any sig-nificant neck propagation. The simple elastic-plastic model show similar local strainrates as the experiment however does show a noticeable thinner neck.

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  • 35.
    Andraéy, Erik
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Development of verified FE simulation method on crimp joint with gasket: A combined experimental and numerical study2021Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    When developing drivetrain cooling modules for commercial vehicles, the top priority is the strength of the products. The reason lays within the structural change that companies are undergoing where the warehouses are minimized and the companies are relying on the transportation of commercial vehicles. If a drivetrain cooling module would fail to maintain a targeted temperature range of the drivetrain, there is not long until the vehicle is forced to a stop. At worst, the downtime of commercial vehicles can cause companies to come to a halt as well. Therefore, developing verified FE simulation methods together with strength verification tests, are some of the core activities to ensure the strength of the cooling modules before implementation in vehicles.

    One of the methods that have not been sufficiently verified regards how to perform structural FEA on a crimp joint with a gasket. A crimp joint is established through a hemming process, where the aluminium header tabs are crimped over the polyamide tank, creating a watertight seal together with a gasket. The objective of this master’s thesis is to verify the existing simulation methods of the crimp joint and determine the margin of error with respect to strains. The objective of this thesis is also to develop a verified FE simulation method with a lower margin of error compared to the existing methods. The verification of the methods has been conducted through a comparison between numerical results and an experimental stress analysis, where the strain located on the header is measured with strain gauges in a pressure pulsation rig.

    The average margin of error found on the three existing methods of simulating the crimp joint was 39,7%, 13,4%, and 11,5% located on the outer bottom dimensioning radius of the crimp joint at a pressure of 100 kPa. However, the method used to determine the margin of error was found to be invalid, but the margin of error is only slightly affected by the verification method where the existing methods still are insufficiently representing the crimp joint. The method of determining the margin of error was then corrected for the development of the new method to represent the crimp joint in the FE model. The developed method in this thesis has an average margin of error of 6,9% at 100, 160, 220, and 260 kPa.

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  • 36.
    Andreasson, Eskil
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Mechanics and Failure in Thin Material Layers: Towards Realistic Package Opening Simulations2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The final goal of this PhD-work is an efficient and user-friendly finite element modelling strategy targeting an industrial available package opening application.  In order to reach this goal, different experimental mechanical and fracture mechanical tests were continuously refined to characterize the studied materials. Furthermore, the governing deformation mechanisms and mechanical properties involved in the opening sequence were quantified with full field experimental techniques to extract the intrinsic material response. An identification process to calibrate the material model parameters with inverse modelling analysis is proposed. Constitutive models, based on the experimental results for the two continuum materials, aluminium and polymer materials, and how to address the progressive damage modelling have been concerned in this work. The results and methods considered are general and can be applied in other industries where polymer and metal material are present.                                                                   

    This work has shown that it is possible to select constitutive material models in conjunction with continuum material damage models, adequately predicting the mechanical behaviour in thin laminated packaging materials. Finally, with a slight modification of already available techniques and functionalities in a commercial general-purpose finite element software, it was possible to build a simulation model replicating the physical behaviour of an opening device. A comparison of the results between the experimental opening and the virtual opening model showed a good correlation.

    The advantage with the developed modelling approach is that it is possible to modify the material composition of the laminate. Individual material layers can be altered, and the mechanical properties, thickness or geometrical shape can be changed. Furthermore, the model is flexible and a new opening design with a different geometry and load case can easily be implemented and changed in the simulation model. Therefore, this type of simulation model is prepared to simulate sustainable materials in packages and will be a useful tool for decision support early in the concept selection in technology and development projects.

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  • 37.
    Andreasson, Eskil
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Realistic Package Opening Simulations: An Experimental Mechanics and Physics Based Approach2015Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    A finite element modeling strategy targeting package opening simulations is the final goal with this work. The developed simulation model will be used to proactively predict the opening compatibility early in the development process of a new opening device and/or a new packaging material. To be able to create such a model, the focus is to develop a combined and integrated physical/virtual test procedure for mechanical characterization and calibration of thin packaging materials. Furthermore, the governing mechanical properties of the materials involved in the opening performance needs to be identified and quantified with experiments. Different experimental techniques complemented with video recording equipment were refined and utilized during the course of work. An automatic or semi-automatic material model parameter identification process involving video capturing of the deformation process and inverse modeling is proposed for the different packaging material layers. Both an accurate continuum model and a damage material model, used in the simulation model, were translated and extracted from the experimental test results. The results presented show that it is possible to select constitutive material models in conjunction with continuum material damage models, adequately predicting the mechanical behavior of intended failure in thin laminated packaging materials. A thorough material mechanics understanding of individual material layers evolution of microstructure and the micro mechanisms involved in the deformation process is essential for appropriate selection of numerical material models. Finally, with a slight modification of already available techniques and functionalities in the commercial finite element software AbaqusTM it was possible to build the suitable simulation model. To build a realistic simulation model an accurate description of the geometrical features is important. Therefore, advancements within the experimental visualization techniques utilizing a combination of video recording, photoelasticity and Scanning Electron Microscopy (SEM) of the micro structure have enabled extraction of geometries and additional information from ordinary standard experimental tests. Finally, a comparison of the experimental opening and the virtual opening, showed a good correlation with the developed finite element modeling technique. The advantage with the developed modeling approach is that it is possible to modify the material composition of the laminate. Individual material layers can be altered and the mechanical properties, thickness or geometrical shape can be changed. Furthermore, the model is flexible and a new opening device i.e. geometry and load case can easily be adopted in the simulation model. Therefore, this type of simulation model is a useful tool and can be used for decision support early in the concept selection of development projects.

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  • 38.
    Andreasson, Eskil
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Jönsson, Joel
    Tetra Pak, SWE.
    Advancements in package opening simulations2014In: Procedia Materials Science / [ed] Zhang, Z; Skallerud, B; Thaulow, C; Ostby, E; He, J, Elsevier, 2014, Vol. 3, p. 1441-1446Conference paper (Refereed)
    Abstract [en]

    The fracture mechanical phenomenon occurring during the opening of a beverage package is rather complex to simulate. Reliable and calibrated numerical material models describing thin layers of packaging materials are needed. Selection of appropriate constitutive models for the continuum material models and how to address the progressive damage modeling in various loading scenarios is also of great importance. The inverse modeling technique combined with video recording of the involved deformation mechanisms is utilized for identification of the material parameters. Large deformation, anisotropic non-linear material behavior, adhesion and fracture mechanics are all identified effects that are needed to be included in the virtual opening model. The results presented in this paper shows that it is possible to select material models in conjunction with continuum material damage models, adequately predicting the mechanical behavior of failure in thin laminated packaging materials. Already available techniques and functionalities in the commercial finite element software Abaqus are used. Furthermore, accurate descriptions of the included geometrical features are important. Advancements have therefore also been made within the experimental techniques utilizing a combination of microCT-scan, SEM and photoelasticity enabling extraction of geometries and additional information from ordinary experimental tests and broken specimens. Finally, comparison of the experimental opening and the virtual opening, showed a good correlation with the developed finite element modeling technique.

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  • 39.
    Andreasson, Eskil
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Lindström, Tommy
    Lunds Universitet, SWE.
    Käck, Britta
    Altair Engineering AB, SWE.
    Malmberg, Christoffer
    Saab AB, SWE.
    Asp, Ann Magret
    Tetra Pak AB, SWE.
    Simulation of thin aluminium-foil in the packaging industry2017In: AIP Conference Proceedings / [ed] Brabazon D.,Ul Ahad I.,Naher S., American Institute of Physics Inc. , 2017, Vol. 1896, article id 160014Conference paper (Refereed)
    Abstract [en]

    This work present an approach of how to account for the anisotropic mechanical material behaviour in the simulation models of the thin aluminium foil layer (≈10 μm) used in the Packaging Industry. Furthermore, the experimental results from uniaxial tensile tests are parameterised into an analytical expression and the slope of the hardening subsequently extended way beyond the experimental data points. This in order to accommodate the locally high stresses present in the experiments at the neck formation. An analytical expression, denominated Ramberg-Osgood, is used to describe the non-linear mechanical behaviour. Moreover it is possible with a direct method to translate the experimental uniaxial tensile test results into useful numerical material model parameters in Abaqus™. In addition to this the extended material behaviour including the plastic flow i.e. hardening, valid after onset of localisation, the described procedure can also capture the microscopic events, i.e. geometrical thinning, ongoing in the deformation of the aluminium foil. This method has earlier successfully been applied by Petri Mäkelä for paperboard material [1]. The engineering sound and parameterised description of the mechanical material behaviour facilitates an efficient categorisation of different aluminium foil alloys and aid the identification of the correct anisotropic (RD/TD/45°) mechanical material behaviour derived from the physical testing. © 2017 Author(s).

  • 40.
    Arif, Habib Ullah
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Koncept för automatisk bromsning & parkeringssystem i bilar vid sömnig eller akuta hälsofel situationer2020Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
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    Koncept för automatisk bromsning & parkeringssystem i bilar vid sömnig eller akuta hälsofel situationer
  • 41.
    Asbjorn Sorensen, Charlotte
    et al.
    Malmö Högskola, SWE.
    Warell, Anders
    Lunds universitet, SWE.
    Jagtap, Santosh
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Material selection: A qualitative case study of five design consultancies2017In: DS87-1 PROCEEDINGS OF THE 21ST INTERNATIONAL CONFERENCE ON ENGINEERING DESIGN (ICED 17), VOL 1: RESOURCE SENSITIVE DESIGN, DESIGN RESEARCH APPLICATIONS AND CASE STUDIES / [ed] Maier, A; Skec, S; Kim, H; Kokkolaras, M; Oehmen, J; Fadel, G; Salustri, F; VanDerLoos, M, The Design Society, 2017, no DS87-1, p. 439-448, article id DS87-1Conference paper (Refereed)
    Abstract [en]

    This qualitative case study aims at understanding when and how industrial designers, working in design consultancies, engage in activities that will influence material selection in the design process. While the extant literature presents material selection processes as a sequence of activities aimed at finding candidate materials, there is paucity of research on material criteria activities. Formulating material criteria is an activity that is performed during all design phases and they become clearer and more complete throughout the project. For the case studies, explorative semi-structured interviews were conducted with five industrial designers with 10 years of work experience or more. The results suggest (a) that risk management has a major influence on the material selection process, (b) that negotiations of project boundaries in the 'fuzzy' pre-design phase has crucial influence on the risk management aspect of the material criteria activities, and (c) a lack of awareness that design briefs usually outline material criteria expressed as sensorial characteristics, which are later translated by engineering into final material criteria used for the material selection process.

  • 42.
    Asbjörn Sörensen, Charlotte
    et al.
    Malmö Högskola, SWE.
    Jagtap, Santosh
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Warell, Anders
    Lunds Universitet, SWE.
    A shift from technical properties towards sensorial characteristics in product design education2017In: Proceedings of the 19th International Conference on Engineering and Product Design Education:: Building Community: Design Education for a Sustainable Future / [ed] Gulden T.,Pavel N.,Kovacevic A.,Buck L.,Bohemia E.,Berg A., Institution of Engineering Designers, The Design Society , 2017, p. 388-393Conference paper (Refereed)
    Abstract [en]

    The aim of this study is to evaluate a new pedagogic approach implemented in a compulsory materials course for product design students at bachelors level at ABC University. When developing a new curriculum for the material course, a decision was made to teach materials and production methods in a contextualized setting with emphasis on how students can deal with materials in a design process. Methods can be seen as mental tools that aid the design students in navigating complexity and offers them a structure to deal with unfamiliar territories. After an evaluation, some methods, guidelines and tools were selected to integrate in the compulsory materials course for the product design students, e.g. the Expressive-Sensorial Atlas [1], Meaning Driven Materials Selection [2] and the Material Driven Design method [3]. The implementation is made in two steps in order to test, evaluate and further develop a framework for teaching materials courses to product design students. The study evaluate the first step of implementation in general, and the implementation of the Material Driven Design method in particular. It is hoped that this research can contribute to further development of pedagogical approaches for teaching materials and production methods in a contextualized setting for product design students at bachelors level.

  • 43.
    BAKTASH, IMAN
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Modeling of Electromagnetic Heating of Multi-coil Inductors in Railway Traction Systems2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Inductors are frequently used in railway electrical tractions systems in

    filtering and current limiting operations. Magnetic fields are generated due

    to the flow of large AC currents through the coils, which intend induce

    currents on the coils as well as the metallic components in the vicinity,

    causing electromagnetic heating. The heating may cause temperatures to

    exceed project temperature requirements and in the worst case distort the

    functionality of drive system. The purpose of this work is to simulate the

    Electromagnetic Heating effect of inductors in 3D using COMSOL Multiphysics.

    First a 3D CAD model of the inductor geometry is imported to

    COMSOL and the magnetic fields for a giving current excitation are

    estimated. Then the power losses are fed in to a heat flow simulation to

    predict the temperature distributions. Cooling is simulated by driving cool

    air through the heated coils and the surrounding metal objects. The

    temperature distributions for different current excitations and air flow

    velocities are estimated. Simulation is performed on conceptual project

    inductor model. The 3D inductor modeling approach established in this thesis

    work could be used to characterize the electromagnetic heating issues early

    in the project design phase.

     

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    BTH2015Baktash
  • 44.
    Bandari, Shiva Ram
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Investigation on Flow Control Valve by CFD Simulation2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In a water distribution system, Flow Control Valve is used to control the flow rate in the pipeline connections. In this thesis, a fixed flow control valve is investigated to reduce the flow rate and set to deliver the pre-set flow of 5-6 LPM (litre per minute). Which helps to distribute the water for a maximum period and maintains the usage only for the drinking purpose. A geometry of FCV with a ball check valve is implemented, where the ball check helps to stop the back flow of the fluid from the valve. Detailed inspection of dynamic changes in pressure and flow velocity in the valve are conducted through simulation. The study of fluid properties describes the expected design and specifies the flow structure in the valve. The results of this project demonstrate a good performance of the design-build and influence the requirements. The obtained values in the simulation, analytical and experimental results are compatible, which concludes the survey of FCV is equipped to custom.

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  • 45.
    Bankaoglu, Cagatay
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    IMPACT FAILURE ASSESSMENT ON CRUSHER DISK BY RIGID AND ELASTO-PLASTIC BODY APPROXIMATIONS2014Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Rigid and elasto-plastic body simulations and analytical methods were carried out to identify and assess impact forces based on their contact durations and force magnitudes. Based on the estimations, most severe cases were simulated in ABAQUS to assess the possible damage on crusher disk component of crusher machines, designed and manufactured by MRT System Karlskrona. Further analyses were carried out to combine both impact force estimations and damage assessment. It was concluded that studied case of impact was not a likely scenario to cause the damage occurring under normal operation conditions in the studied type of crusher machines with the material properties considered in this work.

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  • 46.
    Barlo, Alexander
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Failure Prediction of Complex Load Cases in Sheet Metal Forming: Emphasis on Non-Linear Strain Paths, Stretch-Bending and Edge Effects2023Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    With the increased focus on reducing carbon emissions in today’s society, several industries have to overcome new challenges, where especially the automotive industry is under a lot of scrutiny to deliver improved and more environmentally friendly products. To meet the demands from customers and optimize vehicles aerodynamically, new cars often contain complex body geometries, together with advanced materials that are introduced to reduce the total vehicle weight. With the introduction of the complex body components and advanced materials,one area in the automotive industry that has to overcome these challenges is manufacturing engineering, and in particular the departments working with the sheet metal forming process. In this process complex body component geometries can lead to non-linear strain paths and stretch bending load cases, and newly introduced advanced materials can be prone to exhibit behaviour of edge cracks not observed in conventional sheet metals. This thesis takes it onset in the challenges seen in industry today with predicting failure of the three complex load cases: Non-Linear Strain Paths, Stretch-Bending,and Edge Cracks. Through Finite Element simulation attempts are made to accurately predict failure caused by aforementioned load cases in industrial components or experimental setups in an effort to develop post-processing methods that are applicable to all cases.

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  • 47.
    Barlo, Alexander
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Manopulo, Niko
    AutoForm Engineering GmbH, Switzerland .
    Sigvant, Mats
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Endelt, Benny
    Aalborg University, Denmark.
    Trana, Kristoffer
    Volvo Cars Stamping Engineering, Olofström.
    Investigation of a Bending Corrected Forming Limit Surface for Failure Prediction in Sheet Metals2019In: Forming Technology Forum, 2019Conference paper (Refereed)
    Abstract [en]

    Ensuring process feasibility is a high priority in the automotive industry today. Within theCAE departments concerning the manufacturing of body components, one of the most important areas ofinterest is the accurate prediction of failure in components through Finite Element simulations. This paperinvestigates the possibility of introducing the component curvature as a parameter to improve failureprediction. Bending-under-tension specimens with different radii are used to create a Bending CorrectedForming Limit Surface (BC-FLS), and a test die developed at Volvo Cars, depicting production-like scenariosby exposing an AA6016 aluminium alloy blank to a stretch-bending condition with biaxial pre-stretching, isused to validate the proposed model in the commercial Finite Element code AutoFormTM R8. The findings ofthis paper showed that the proposed BC-FLS approach performed well in the failure prediction of the test diecompared to the already in AutoFormTM R8 implemented max failure approach.

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  • 48.
    Barlo, Alexander
    et al.
    Volvo, SWE.
    Sigvant, Mats
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Endelt, Benny
    Aalborg Universitet, DEN.
    On the Failure Prediction of Dual-Phase Steel and Aluminium Alloys Exposed to Combined Tension and Bending2019In: IOP Conference Series: Materials Science and Engineering / [ed] VanDenBoogaard, T; Hazrati, J; Langerak, N, Institute of Physics Publishing , 2019, Vol. 651, no 1, article id 012030Conference paper (Refereed)
    Abstract [en]

    The interest in accurate prediction of failure of sheet metals in the automotive industry has increased significantly over the last two decades. This paper aims to evaluate two failure prediction approaches implemented in the commercial Finite Element code AutoFormplus R7.04; (i) the standard Forming Limit Diagram (FLD), and (ii) the Non-linear Forming Limit Diagram. The evaluation will be testing the two approaches accuracy on predicting failure of both an AA6016 aluminium alloy and a CR440Y780T-DP dual-phase steel alloy specimen exposed to combined tension and bending. Based on the findings of this study, it is concluded that neither of the evaluated approaches is able to accurately predict failure in both cases presented. © Published under licence by IOP Publishing Ltd.

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    On the Failure Prediction of Dual-Phase Steel and Aluminium Alloys
  • 49.
    Barlo, Alexander
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Sigvant, Mats
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Islam, Md. Shafiqul
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Perez, Ll
    RISE, Sweden.
    Olofsson, E.
    Volvo Cars, Gothenburg, Sweden..
    Al-Fadhli, M.
    Volvo Cars, Olofstrom, Sweden..
    Tuan Pham, Quoc
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Pilthammar, Johan
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Odenberger, E-L
    RISE, Sweden.
    Proposal of a New Tool for Pre-Straining Operations of Sheet Metals and an Initial Investigation of CR4 Mild Steel Formability2023In: 42ND CONFERENCE OF THE INTERNATIONAL DEEP DRAWING RESEARCH GROUP / [ed] Asnafi, N Lindgren, LE, IOP PUBLISHING LTD , 2023, Vol. 1284, article id 012079Conference paper (Refereed)
    Abstract [en]

    With the increased focus on reducing carbon emissions in the automotive industry, more advanced materials are introduced to reduce the vehicle weight, and more complex component geometries are designed to both satisfy customer demands and to optimize the vehicle aerodynamically. With the increase in component complexity, the strain paths produced during the forming operation of car body components often display a highly non-linear behavior which makes the task of failure prediction during the manufacturing feasibility studies more difficult. Therefore, CAE engineers need better capabilities to predict failure induced by strain path nonlinearity. This study proposes a new tool designed for creating bi-linear strain paths, by performing a pre-strain of a sheet large enough to cut out Nakajima specimens to perform the post-straining in any direction. From five pre-straining tests the tool present a stable pre-straining operation with a uniform strain field in a radius of 100 [mm] from the centre, corresponding to the region of interest of a Nakajima specimen. From the five pre-strained samples, different Nakajima specimens are cut transverse and longitudinal to the rolling direction and a failure prediction approach in an alternative, path independent evaluation space was used to predict the onset of necking with promising results.

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  • 50.
    Barlo, Alexander
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Sigvant, Mats
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Kesti, V.
    SSAB Europe Oy, Finland..
    Islam, Md. Shafiqul
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Tuan Pham, Quoc
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Pilthammar, Johan
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Determination of Edge Fracture Limit Strain for AHSS in the ISO-16630 Hole Expansion Test2023In: 42ND CONFERENCE OF THE INTERNATIONAL DEEP DRAWING RESEARCH GROUP / [ed] Asnafi, N Lindgren, LE, IOP PUBLISHING LTD , 2023, Vol. 1284, article id 012027Conference paper (Refereed)
    Abstract [en]

    With the increased demand for application of sustainable materials and lightweight structures, the sheet metal forming industry is forced to push existing materials to the limits. One area where this is particular difficult is when it comes to assessing the formability limit for sheet edges. For decades, the ISO-16630 Hole Expansion Test (HET) has been the industry standard for expressing the edge formability of sheet metals through the Hole Expansion Ratio (HER). However, in recent years, this test has been criticized for its high scatter in results for repeated experiments. This scatter has been suspected to be caused by the operator-reliant post-processing of the test, or variations in the cutting conditions for the different test specimens. This study investigates the impact of shifting the evaluation point of the test from the through-thickness crack to the onset of surface failure on the reported scatter, as well as performs inverse modeling of the Hole Expansion Test to obtain an edge limit strain value.

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