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  • 1.
    Abdul, Nishan
    et al.
    University of Skövde, School of Engineering Science.
    Palmborg, Henrik
    University of Skövde, School of Engineering Science.
    Analys och lösningsförslag för logistik inom Volvo Powertrain2020Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Volvo Powertrain in Skövde is a factory that manufactures truck and bus engines with various volumes. The factory has several departments and functions that together make up the three main parts: foundry, processing, and assembly. One of these departments is logistics, which has the task of organizing internal logistics activities at the company. The logistics department strives to provide good customer service with low costs and environmental impact. The work carried out concerns parts of the current data management system used within the departments warehouse management structure. The current system is not very user-friendly which makes it difficult to get an overview of the storage areas. This, together with other problems, causes the logistics department to experience the system as time-consuming and deficient. The purpose of this work is to produce solution proposals that address the shortcomings of the current system utilizing minimal investments, while facilitating data management and providing better visualization of the warehouses. The methods chosen to achieve the purpose of the work are motivated by a literature study.

    To compare solution proposals, standard IEEE-830 was used as a basis for producing a requirements specification. The requirements specification based on observations and interviews conducted with the logistics department. The solution proposals presented are based on interviews conducted at other sites within the Volvo Group and have been compared with the requirements specification to see how well they fit the needs of the logistics department. The methods used during the execution of the work are also discussed, and finally, recommendations are made for future work.

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  • 2.
    Adamson, Göran
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. De Montfort University, UK.
    A Novel Method for Adaptive Control of Manufacturing Equipment in Cloud Environments2018Doctoral thesis, monograph (Other academic)
    Abstract [en]

    The ability to adaptively control manufacturing equipment, both in local and distributed environments, is becoming increasingly more important for many manufacturing companies.

    One important reason for this is that manufacturing companies are facing increasing levels of changes, variations and uncertainty, caused by both internal and external factors, which can negatively impact their performance. Frequently changing consumer requirements and market demands usually lead to variations in manufacturing quantities, product design and shorter product life-cycles. Variations in manufacturing capability and functionality, such as equipment breakdowns, missing/worn/broken tools and delays, also contribute to a high level of uncertainty. The result is unpredictable manufacturing system performance, with an increased number of unforeseen events occurring in these systems. Events which are difficult for traditional planning and control systems to satisfactorily manage.

    For manufacturing scenarios such as these, the use of real-time manufacturing information and intelligence is necessary to enable manufacturing activities to be performed according to actual manufacturing conditions and requirements, and not according to a pre-determined process plan. Therefore, there is a need for an event-driven control approach to facilitate adaptive decision-making and dynamic control capabilities.

    Another reason driving the move for adaptive control of manufacturing equipment is the trend of increasing globalization, which forces manufacturing industry to focus on more cost-effective manufacturing systems and collaboration within global supply chains and manufacturing networks. Cloud Manufacturing is evolving as a new manufacturing paradigm to match this trend, enabling the mutually advantageous sharing of resources, knowledge and information between distributed companies and manufacturing units. One of the crucial objectives for Cloud Manufacturing is the coordinated planning, control and execution of discrete manufacturing operations in collaborative and networked environments. Therefore, there is also a need that such an event-driven control approach supports the control of distributed manufacturing equipment.

    The aim of this research study is to define and verify a novel and comprehensive method for adaptive control of manufacturing equipment in cloud environments.

    The presented research follows the Design Science Research methodology. From a review of research literature, problems regarding adaptive manufacturing equipment control have been identified. A control approach, building on a structure of event-driven Manufacturing Feature Function Blocks, supported by an Information Framework, has been formulated. The Function Block structure is constructed to generate real-time control instructions, triggered by events from the manufacturing environment. The Information Framework uses the concept of Ontologies and The Semantic Web to enable description and matching of manufacturing resource capabilities and manufacturing task requests in distributed environments, e.g. within Cloud Manufacturing. The suggested control approach has been designed and instantiated, implemented as prototype systems for both local and distributed manufacturing scenarios, in both real and virtual applications. In these systems, event-driven Assembly Feature Function Blocks for adaptive control of robotic assembly tasks have been used to demonstrate the applicability of the control approach. The utility and performance of these prototype systems have been tested, verified and evaluated for different assembly scenarios.

    The proposed control approach has many promising characteristics for use within both local and distributed environments, such as cloud environments. The biggest advantage compared to traditional control is that the required control is created at run-time according to actual manufacturing conditions.

    The biggest obstacle for being applicable to its full extent is manufacturing equipment controlled by proprietary control systems, with native control languages. To take the full advantage of the IEC Function Block control approach, controllers which can interface, interpret and execute these Function Blocks directly, are necessary.

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  • 3.
    Adamson, Göran
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Holm, Magnus
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Moore, Philip
    Academy of Innovation & Research, Falmouth University, Cornwall, United kingdom.
    Wang, Lihui
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. KTH Royal Institute of Technology, Stockholm, Sweden.
    A Cloud Service Control Approach for Distributed and Adaptive Equipment Control in Cloud Environments2016In: Procedia CIRP, ISSN 2212-8271, E-ISSN 2212-8271, Vol. 41, p. 644-649Article in journal (Refereed)
    Abstract [en]

    A developing trend within the manufacturing shop-floor domain is the move of manufacturing activities into cloud environments, as scalable, on-demand and pay-per-usage cloud services. This will radically change traditional manufacturing, as borderless, distributed and collaborative manufacturing missions between volatile, best suited groups of partners will impose a multitude of advantages. The evolving Cloud Manufacturing (CM) paradigm will enable this new manufacturing concept, and on-going research has described many of its anticipated core virtues and enabling technologies. However, a major key enabling technology within CM which has not yet been fully addressed is the dynamic and distributed planning, control and execution of scattered and cooperating shop-floor equipment, completing joint manufacturing tasks.

    In this paper, the technological perspective for a cloud service-based control approach is described, and how it could be implemented. Existing manufacturing resources, such as soft, hard and capability resources, can be packaged as cloud services, and combined to create different levels of equipment or manufacturing control, ranging from low-level control of single machines or devices (e.g. Robot Control-as-a-Service), up to the execution of high level multi-process manufacturing tasks (e.g. Manufacturing-as-a-Service). A multi-layer control approach, featuring adaptive decision-making for both global and local environmental conditions, is proposed. This is realized through the use of a network of intelligent and distributable decision modules such as event-driven Function Blocks, enabling run-time manufacturing activities to be performed according to actual manufacturing conditions. The control system’s integration to the CM cloud service management functionality is also described.

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  • 4.
    Adamson, Göran
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Wang, Lihui
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. Royal Institute of Technology, Stockholm, Sweden.
    Holm, Magnus
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Moore, Philip
    Falmouth University, Cornwall, UK.
    Adaptive Robot Control as a Service in Cloud Manufacturing2015In: ASME 2015 International Manufacturing Science and Engineering Conference: Volume 2: Materials; Biomanufacturing; Properties, Applications and Systems; Sustainable Manufacturing, ASME Press, 2015, Vol. 2, p. Paper No. MSEC2015-9479-Conference paper (Refereed)
    Abstract [en]

    The interest for implementing the concept of Manufacturing-as-a-Service is increasing as concepts for letting the manufacturing shop-floor domain take advantage of the cloud appears. Combining technologies such as Internet of Things, Cloud Computing, Semantic Web, virtualisation and service-oriented technologies with advanced manufacturing models, information and communication technologies, Cloud Manufacturing (CM) is emerging as a new manufacturing paradigm. The ideas of on-demand, scalable and pay-for-usage resource-sharing in this concept will move manufacturing towards distributed and collaborative missions in volatile partnerships. This will require a control approach for distributed planning and execution of cooperating manufacturing activities. Without control based on both global and local environmental conditions, the advantages of CM will not be fulfilled.

    By utilising smart and distributable decision modules such as event-driven FBs, run-time manufacturing operations in a distributed environment may be adjusted to prevailing manufacturing conditions. Packaged in a cloud service for manufacturing equipment control, it will satisfy the control needs in CM. By combining different resource types, such as hard, soft and capability resources, the cloud service Robot Control-as-a-Service can be realised.

    This paper describes the functional perspective and enabling technologies for a control approach for robotic assembly tasks in CM, and describes a scenario for its implementation.

  • 5.
    Adamson, Göran
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Wang, Lihui
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. Production Engineering, KTH Royal Institute of Technology, Stockholm, Sweden.
    Holm, Magnus
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Moore, Philip
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. Academy for Innovation & Research, Falmouth University, UK.
    Adaptive Robotic Control in Cloud Environments2014In: Proceedings of the 24th International Conference on Flexible Automation and Intelligent Manufacturing / [ed] F. Frank Chen, Lancaster, Pennsylvania, USA: DEStech Publications, Inc , 2014, p. 37-44Conference paper (Refereed)
    Abstract [en]

    The increasing globalization is a trend which forces manufacturing industry of today to focus on more cost-effective manufacturing systems and collaboration within global supply chains and manufacturing networks. Cloud Manufacturing (CM) is evolving as a new manufacturing paradigm to match this trend, enabling the mutually advantageous sharing of resources, knowledge and information between distributed companies and manufacturing units. Providing a framework for collaboration within complex and critical tasks, such as manufacturing and design, it increases the companies’ ability to successfully compete on a global marketplace. One of the major, crucial objectives for CM is the coordinated planning, control and execution of discrete manufacturing operations in a collaborative and networked environment. This paper describes the overall concept of adaptive Function Block control of manufacturing equipment in Cloud environments, with the specific focus on robotic assembly operations, and presents Cloud Robotics as “Robot Control-as-a-Service” within CM.

  • 6.
    Adamson, Göran
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Wang, Lihui
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. Department of Production Engineering, KTH Royal Institute of Technology, Stockholm, Sweden.
    Holm, Magnus
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Moore, Philip
    Academy for Innovation & Research, Falmouth University, Cornwall, United Kingdom.
    Cloud Manufacturing: A Critical Review of Recent Development and Future Trends2017In: International journal of computer integrated manufacturing (Print), ISSN 0951-192X, E-ISSN 1362-3052, Vol. 30, no 4-5, p. 347-380Article in journal (Refereed)
    Abstract [en]

    There is an on-going paradigm shift in manufacturing, in which modern manufacturing industry is changing towards global manufacturing networks and supply chains. This will lead to the flexible usage of different globally distributed, scalable and sustainable, service-oriented manufacturing systems and resources. Combining recently emerged technologies, such as Internet of Things, Cloud Computing, Semantic Web, service-oriented technologies, virtualisation and advanced high-performance computing technologies, with advanced manufacturing models and information technologies, Cloud Manufacturing is a new manufacturing paradigm built on resource sharing, supporting and driving this change.

    It is envisioned that companies in all sectors of manufacturing will be able to package their resources and know-hows in the Cloud, making them conveniently available for others through pay-as-you-go, which is also timely and economically attractive. Resources, e.g. manufacturing software tools, applications, knowledge and fabrication capabilities and equipment, will then be made accessible to presumptive consumers on a worldwide basis.

    Cloud Manufacturing has been in focus for a great deal of research interest and suggested applications during recent years, by both industrial and academic communities. After surveying a vast array of available publications, this paper presents an up-to-date literature review together with identified outstanding research issues, and future trends and directions within Cloud Manufacturing.

  • 7.
    Adamson, Göran
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Wang, Lihui
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. Royal Institute of Technology, Stockholm, Sweden.
    Holm, Magnus
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Moore, Philip
    Falmouth University, Cornwall, United Kingdom.
    Feature-Based Adaptive Manufacturing Equipment Control for Cloud Environments2016In: Proceedings of the ASME 11th International Manufacturing Science and Engineering Conference, 2016, vol 2, American Society of Mechanical Engineers (ASME) , 2016, article id UNSP V002T04A019Conference paper (Refereed)
    Abstract [en]

    The ideas of on-demand, scalable and pay-for-usage resource-sharing in Cloud Manufacturing are steadily attracting more interest. For implementing the concept of Manufacturing as-a-Service in a cloud environment, description models and implementation language for resources and their capabilities are required. A standardized approach for systemived virtualization, servisilisation, retrieval, selection and composition into higher levels of functionality is necessary. For the collaborative sharing and use of networked manufacturing resources there is also a need for a control approach for distributed manufacturing equipment. In this paper, the technological perspective for an adaptive cloud service-based control approach is described, and a supporting information model for its implementation. The control is realized through the use of a network of intelligent and distributable Function Block decision modules, enabling run-time manufacturing activities to be performed according to actual manufacturing conditions. The control system's integration to the cloud service management functionality is described, as well as a feature-level capability model and the use of ontologies and the Semantic Web.

  • 8.
    Adamson, Göran
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Wang, Lihui
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. Production Engineering KTH Royal Institute of Technology Stockholm, Sweden.
    Holm, Magnus
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Moore, Philip
    Academy for Innovation & Research, Falmouth University, Cornwall, United Kingdom.
    Function Block Approach for Adaptive Robotic Control in Virtual and Real Environments2014In: Proceedings of the 14th Mechatronics Forum International Conference, Mechatronics 2014 / [ed] Leo J. De Vin; Jorge Solis, Karlstad: Karlstads universitet, 2014, p. 473-479Conference paper (Refereed)
    Abstract [en]

    Many manufacturing companies are facing an increasing amount of changes and uncertainty, caused by both internal and external factors. Frequently changing customer and market demands lead to variations in manufacturing quantities, product design and shorter product life-cycles, and variations in manufacturing capability and functionality contribute to a high level of uncertainty. The result is unpredictable manufacturing system performance, with an increased number of unforeseen events occurring in these systems. Such events are difficult for traditional planning and control systems to satisfactorily manage. For scenarios like these, with a dynamically changing manufacturing environment, adaptive decision making is crucial for successfully performing manufacturing operations. Relying on real-time information of manufacturing processes and operations, and their enabling resources, adaptive decision making can be realized with a control approach combining IEC 61499 event-driven Function Blocks (FBs) with manufacturing features. These FBs are small decision-making modules with embedded algorithms designed to generate the desired equipment control code. When dynamically triggered by event inputs, parameter values in their data inputs are forwarded to the appropriate algorithms, which generate new events and data output as control instructions. The data inputs also include monitored real-time information which allows the dynamic creation of equipment control code adapted to the actual run-time conditions on the shop-floor. Manufacturing features build on the concept that a manufacturing task can be broken down into a sequence of minor basic operations, in this research assembly features (AFs). These features define atomic assembly operations, and by combining and implementing these in the event-driven FB embedded algorithms, automatic code generation is possible. A test case with a virtual robot assembly cell is presented, demonstrating the functionality of the proposed control approach.

  • 9.
    Adamson, Göran
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Wang, Lihui
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. Department of Production Engineering, Royal Institute of Technology, Stockholm, Sweden.
    Moore, Philip
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Feature-based control and information framework for adaptive and distributed manufacturing in cyber physical systems2017In: Journal of manufacturing systems, ISSN 0278-6125, E-ISSN 1878-6642, Vol. 43, p. 305-315Article in journal (Refereed)
    Abstract [en]

    Modern distributed manufacturing within Industry 4.0, supported by Cyber Physical Systems (CPSs), offers many promising capabilities regarding effective and flexible manufacturing, but there remain many challenges which may hinder its exploitation fully. One major issue is how to automatically control manufacturing equipment, e.g. industrial robots and CNC-machines, in an adaptive and effective manner. For collaborative sharing and use of distributed and networked manufacturing resources, a coherent, standardised approach for systemised planning and control at different manufacturing system levels and locations is a paramount prerequisite.

    In this paper, the concept of feature-based manufacturing for adaptive equipment control and resource-task matching in distributed and collaborative CPS manufacturing environments is presented. The concept has a product perspective and builds on the combination of product manufacturing features and event-driven Function Blocks (FB) of the IEC 61499 standard. Distributed control is realised through the use of networked and smart FB decision modules, enabling the performance of collaborative run-time manufacturing activities according to actual manufacturing conditions. A feature-based information framework supporting the matching of manufacturing resources and tasks, as well as the feature-FB control concept, and a demonstration with a cyber-physical robot application, are presented.

  • 10.
    Adamson, Göran
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Wang, Lihui
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. Department of Production Engineering, Royal Institute of Technology, Stockholm, Sweden.
    Moore, Philip
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Feature-based Function Block Control Framework for Manufacturing Equipment in Cloud Environments2018In: International Journal of Production Research, ISSN 0020-7543, E-ISSN 1366-588X, Vol. 57, no 12, p. 3954-3974Article in journal (Refereed)
    Abstract [en]

    The ability to adaptively control manufacturing equipment in cloud environments is becoming increasingly more important. Industry 4.0, supported by Cyber Physical Systems and the concept of on-demand, scalable and pay-for-usage resource-sharing in cloud environments offers many promises regarding effective and flexible manufacturing. For implementing the concept of manufacturing services in a cloud environment, a cloud control approach for the sharing and control of networked manufacturing resources is required. This paper presents a cloud service-based control approach which has a product perspective and builds on the combination of event-driven IEC 61499 Function Blocks and product manufacturing features. Distributed control is realised through the use of a networked control structure of such Function Blocks as decision modules, enabling an adaptive run-time behaviour. The control approach has been developed and implemented as prototype systems for both local and distributed manufacturing scenarios, in both real and virtual applications. An application scenario is presented to demonstrate the applicability of the control approach. In this scenario, Assembly Feature-Function Blocks for adaptive control of robotic assembly tasks have been used.

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  • 11.
    Adattil, Ruksana
    University of Skövde, School of Engineering Science.
    Review on impact of worker’s psychosocial environment under operator 4.0 framework2022Independent thesis Advanced level (degree of Master (One Year)), 12 credits / 18 HE creditsStudent thesis
    Abstract [en]

    In manufacturing, emerging digital technologies related to industry 4.0 are playing an assisting role for operators, and just as in previous industrial revolutions the paradigm for operators in the industry is changing. This study has two key goals. The first is to look into the impact of the worker's psychosocial impacts under the operator 4.0 typologies during assembly, training, and maintenance operations, and the second is to look into the potential changes in the operator framework as the industry progresses from 4.0 to 5.0. This study proposed a theoretical framework for assessing psychosocial impacts in operator 4.0 typologies. The proposed framework can be utilized by the company managers, researchers, production engineers, and human resource personnel for the psychosocial risk assessment of the operators in assembly, training, and maintenance operations as self-report questionnaires. This study employed a systematic literature review strategy to answer the study objectives. The findings reveal that the nature of work, the social and organizational environment of work, and individual impacts are all key categories, that might impact operators’ psychosocial environments in assembly, training, and maintenance operations under the operator 4.0 typologies.This study focuses on determining the psychosocial consequences of the operator 4.0 typologies and helps the operators to become more aware, and equipment designers should consider operator psychosocial work conditions when designing new augmented equipment for assisting operators in the work environment. Most advanced technologies are unfamiliar to operators, and they have exhibited a reluctance to accept new technology because it significantly changes their working environment. Which necessitates the training and awareness of operators regarding advanced technologies. Operator 4.0 typologies were introduced with a vision to create a socially sustainable environment for operators. However, the identified psychosocial impacts make it favorable and unfavorable to the operators.

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  • 12.
    Adattil, Ruksana
    et al.
    University of Skövde, School of Engineering Science.
    Thorvald, Peter
    University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment.
    Romero, David
    Tecnológico de Monterrey, Mexico City, Mexico.
    Assessing the Psychosocial Impacts of Industry 4.0 Technologies Adoption in the Operator 4.0: Literature Review & Theoretical Framework2024In: International Journal of Industrial Engineering and Management, ISSN 2217-2661, Vol. 15, no 1, p. 59-80Article, review/survey (Refereed)
    Abstract [en]

    Emerging digital and smart technologies, including wearable and collaborative ones, related to the Industry 4.0 paradigm are playing an assisting, collaborative, and augmenting role for the Operator 4.0, and just as in previous industrial revolutions, the nature of work and the workplace for operators on the shop floor is changing. This literature review aims to look into the impact of digital and smart technologies adoption on the workers’ psychosocial stage under the light of the Operator 4.0 typology. Based on the review conducted, a theoretical framework for assessing the psychosocial impacts (risks) of Industry 4.0 technologies adoption in Operator 4.0 is proposed. The framework can be utilized by company managers, researchers, production engineers, and human resources personnel for carrying out a psychosocial risk assessment of Operator 4.0 in assembly, maintenance, and training operations as these operations get digitally transformed and smartified based on self-report questionnaires. Findings reveal that the nature of work, the social and organizational environment of work, and related individual factors are key categories that might affect the Operator 4.0 psychosocial stage on the shop floor.

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  • 13.
    Adawi, Rahim
    University of Skövde, School of Engineering Science.
    Preventing fatal effects of overworking: Product design solution2018Independent thesis Basic level (university diploma), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    “Overworking to death” is a phenomenon that has been noticeable in developing countries. The cause of death is mainly through ischemic strokes. While the victims’ occupations differed, they all shared a common characteristic, being positioned in a sedentary work, ranging from IT workers to doctors. This project’s aim was to develop a product that prevented or decreased the strokes that derived from sedentary overwork. This was mainly tackled by preventing one of the three causes of developing blood props, slowed blood flow. In order to gather rich data of the phenomenon, a qualitative study was conducted in China, during two months. By doing an extensive structured sampling, information rich data could be gathered during a short period of time. Data were derived from observations, questionnaires and an interview, which then was interpreted to customer needs and the final product specification. The final product became a trouser with an in built dynamic compression mechanic, that can compress the veins mostly during sitting activities, in order to prevent blood stasis. The compression mechanic works like the Chinese finger trap; compressing the calves while sitting and stretching the legs forward. It is made only out of polysaccharides fibres; cotton and corn.

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    PREVENTING FATAL EFFECTS OF OVERWORKING – PRODUCT DESIGN SOLUTION / Rahim_Adawi
  • 14.
    Adolfsson, Anton
    et al.
    University of Skövde, School of Engineering Science.
    Norelius, Mattias
    University of Skövde, School of Engineering Science.
    Reducering av kundreklamationer på ett tillverkande företag med hjälp av lean- och produktionstekniska verktyg2020Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Kinnarps is a company that manufactures office furniture and provides workplace solutions for offices and public environments. This project is performed at a manual workstation that packages table legs, this station is responsible for a significant amount of customer complaint costs due to wrong table legs being packaged and sent to the customers. The purpose of this project is to present suggestions for improvement that reduce the risk of packaging errors by using production tools and methods. To achieve the purpose of this project a data collection is to be performed by analyzing historical data and performing observations and interviews. After the data collection the cause of the event is to be found.Theory used to strengthen the choice of methods performed is presented in the theoretical frame of reference. Similar projects have also been studied and are presented in the literature review. The similar projects that were studied can in some way be related to this project and its conclusions.The empirical study was performed by analyzing historical data of the last years customer complaints costs, observations according to the gemba methodology, interviews and conversations with the staff. The costs of customer complaints for the last year was around 723 000 SEK. With the results of the performed methods an Ishikawa diagram was created to identify the causes of the packaging errors. The Ishikawa diagram combined with the theoretical frame of reference and literature review was used to develop three suggestions for improvement that help reduce the amount of customer complaints caused by packaging errors.All suggestions for improvement have been validated by analyzing the effectiveness, cost and the amount of work needed to implement the suggestions. The validations process resulted in a barcode scanner being the most suitable suggestion. By implementing a barcode scanner, the customer complaints could be reduced by an estimate of 92% which corresponds to saving around 665 000 SEK per year in customer complaint costs.

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  • 15.
    Ahmed, Adell
    University of Skövde, School of Engineering Science.
    Analys och simulering av produktionsflödet på ett tillverkningsföretag: Simulering kombinerat med Lean-principer2018Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Production concurrence within manufacturing companies is continuously increasing due to production requirements and demand of mass produced customized goods. In order to meet customers’ requirements nowadays, companies need to increase customize production without suffering a loss of quality. In pursuance of an increased production on the main shop floor of the industrial partner involved in this project, the company investigates the idea of investing in an automated pressing machine to centralize the process outside different assembly lines. With the help of automation, simulation, and Lean, the potential of the company to reduce lead times to satisfy the customer needs can be increased.

    The aim of this final year project is to investigate the potential of a stator pressing machine to manage the supply of product parts to four assembly lines. One of the requirements is that the yearly volume of the new system could be increased by 50%.

    The methodology used in this study is based on Lean, simulation, and optimization. In order to have an overview of the problem, a situation analysis was made on the current production flow. Therefore, a data collection process was performed through observations, continuous communication with matter experts, and historical data. This data was used to analyze the system and feed the simulation model of the proposed new system. Different Lean tools were also used for the analysis and improvement of the system.

    The company presented ideas on how they wanted the production flow to look like, which were then further developed and used as a basis for the improvement suggestions. One requirement was that the solution had to be Lean inspired.

    The aim of the study was achieved by creating a simulation model to test how the system would behave in different configurations. A first scenario designed as a Pull flow system where the products were only produced according to demand. The second scenario was a Push based system without considering just-in-time production. The first scenario was presented as suggestion for final solution.

    The result from the simulation scenarios showed a clear difference between the two systems. The Pull flow was more suitable due to a drastic decrease in both number of products as work- in-progress and lead time. The final solution, using a Kanban method, and a suggestion for the production layout of the future production flow is presented in the report.

  • 16.
    Ahmed, Zakarie
    et al.
    University of Skövde, School of Engineering Science.
    Nasani, Rami
    University of Skövde, School of Engineering Science.
    Modellering och emulering av en människa- robot samarbetande arbetscell2019Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Collaborative robots are a key challenge in industrial development. The problem today is that industrial robots are not adapted for close collaboration with humans and security gates are a need. This study focuses on developing an emulation model that can demonstrate such collaboration without the need for security gates. The project is based on the concept (virtual commissioning) which is about using emulation tools to develop a digital twin that is a copy of a physical system. With the help of the model, the system's functions and program code will be tested and validated before a real implementation is performed. On behalf of the University of Skövde, the thesis work was carried out to investigate the possibility of a close collaboration between a person and industrial robot in a virtual environment. In the study, two different methods have been developed to investigate the possibility of a collaboration but also to develop an emulation model. With this, operating lists have been created to clarify the person and the robot work tasks. Process scenarios were then created to demonstrate how such collaboration can take place in a virtual environment. A functioning emulation model in which man and robot collaborate, was delivered to the University of Skövde. By using the emulation model, the university can create and test different solutions before an implementation of a real system takes place. Finally, an emulation method is proposed that can be used to develop a digital twin.

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  • 17.
    Akrouh Ettaghadouini, Samy
    University of Skövde, School of Engineering Science.
    Metamodelling of a Finite Element Analysis of a Drilling Process with Replaceable Inserts2019Independent thesis Advanced level (degree of Master (One Year)), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    The aim of this project is to create a metamodel from a drilling tool with replaceable inserts from FEA of the machining process using MATLAB and ABAQUS. This report contains research in drilling and in metamodeling using neural networks and the work from the design of the CAD, through FEA and simulations, to the metamodeling, excluding the optimization.

    The work has resulted in a framework where a base FE model of the drill with two inserts that works, but due to time issues and given high cutting speed and feed the results of the FEA and the metamodeling are not very accurate. Therefore, the optimization analysis could not be done. However, it has been shown that feed has a major influence on the inserts temperature than the cutting speed, despite the higher range of this last one.

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  • 18.
    Alasttal, Reema
    et al.
    University of Skövde, School of Engineering Science.
    Nizam, Ali
    University of Skövde, School of Engineering Science.
    Karakterisering av kopparytor för att optimera kvaliteten vid lasersvetsning av hairpins2022Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Development of electric motors in recent years has led to major changes in the automotive industry. This means that the industry is constantly in need of development in order to be able to adapt to new methods and materials. The thesis examines part of this. Laser welding of copper rods, called hairpins, is an important part of the production of an electric motor. During laser welding of copper hairpins, defects occur in the material which results in a poor welding quality which in turn leads to poorer current flow in the electric motor. In this work, a literature review is performed together with experiments to determine which coatings and how the roughness / surface fineness affects the laser welding of copper hairpins. 10 different samples are selected, where contaminated, oxidized and black-painted surfaces are examined with sanded and polished surfaces. The results show that hairpins with a rough surface without any coating have the best welding quality, while hairpins in their original milled shape show the second best welding quality. The conclusion is that coatings increase the porosity, which results in a lower welding quality. More tests need to be performed to ensure the result.

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  • 19.
    Al-Dabagh, Hussain
    et al.
    University of Skövde, School of Engineering Science.
    Wahlström, Daniel
    University of Skövde, School of Engineering Science.
    Konstruktion av gripverktyg för en kollaborativ robot2018Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This work is performed to use a collaborative robot in a mounting process with the aim of solving a type of hidden assembly, in which gear wheels should be synchronized. Because the parts are fragile and heavy, they become difficult for the assembler to handle, which can lead to damage to material or even worse the assembler. A gripping tool should therefore be designed to be used with a collaborative robot in this type of assembly. A comparison of collaborative robots is performed, based on two necessary requirements, where the robot's lifting capacity must be at least 10 kg and that the robots meet safety standards in a safety manner. Where the cobot KUKA LBR IIWA 14 meets these requirements and is considered to be most appropriate for carrying out the task. The robot has a lifting capacity of 14 kg, which means it can handle the gripping tool and the gearbox housing mass, the robot is also considered to be very easy to program. LBR iiwa is a very versatile robot and has no major deficits and therefore the choice of robot is considered to be well completed. A gripping tool has been designed and gone through different stages of development, from concept-generating ideas to design and choosing materials and making FEM analyses. Results suggest that selection of designs and materials on the gripping tool makes it approved for manufacturing and will handle the various loads the gripping tool will be exposed to in carrying out the task.

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  • 20.
    Alfredsson, Henrik
    et al.
    University of Skövde, School of Engineering Science.
    Kyngäs, Johanni
    University of Skövde, School of Engineering Science.
    Simuleringsmodell för kontroll av färdigvarulagers storlek2014Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
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  • 21.
    Alfredsson, K. Svante
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Biel, Anders
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Salimi, Saeed
    University of Skövde.
    Shear testing of thick adhesive layers using the ENF-specimen2015In: International Journal of Adhesion and Adhesives, ISSN 0143-7496, E-ISSN 1879-0127, Vol. 62, p. 130-138Article in journal (Refereed)
  • 22.
    Aljaje, Ibrahim
    et al.
    University of Skövde, School of Engineering Science.
    Eriksson, Kasper
    University of Skövde, School of Engineering Science.
    Analys av produktionsflödet med hjälp av flödessimulering2024Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In today's competitive manufacturing industry, efficiency and improvements in production flow are crucial for companies' success. Simulation has been recognized as a powerful tool for analyzing and enhancing production processes before changes are implemented in reality. This study focuses on creating and analyzing a prototype simulation model to identify improvement opportunities in a painting process at a company that plays a prominent role in the construction industry through its design, manufacturing, and sale of industry-related products, where safety and quality are of utmost importance. The purpose of the study is to develop a simulation model of the production flow through the painting process to identify and analyze potential improvement opportunities. By using the simulation model, different scenarios will be explored to generate improvement suggestions that can increase the efficiency and productivity of the painting process. 

    For this work, the research method Design Science Research (DSR) has been chosen, which provides researchers with a structured framework to streamline research work. The use of DSR has had a significant impact on the design of the research process and the project plan. By applying the DSR method step by step, the project has followed an overall framework to implement Banks' (2014) simulation technique and monitor its progress. Data collection was carried out through document studies, interviews, observations, and time studies to create a foundation for developing the simulation model. Through a structured methodology and the use of simulation tools, a prototype simulation model reflecting the actual production flow through the painting process was constructed. The prototype simulation model was used to identify bottlenecks and effective processes within the painting process. Through experiments and analysis, potential improvement suggestions were formulated to increase the productivity and efficiency of the painting process. The study demonstrates the potential of using simulation models to improve production processes in the manufacturing industry. By identifying and addressing bottlenecks, efficiency and productivity can be increased, leading to increased competitiveness and sustainability for the company. Continued work and development of the simulation model can further improve production processes and achieve long-term improvements.

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  • 23.
    Alkureidi, Haifaa
    University of Skövde, School of Engineering Science.
    Investigations on Industrial Practice of Virtual Commissioning2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Thanks to the advent of Industrial 4.0, automation, digitization, design, manufacturing and the production processes, have become the key to success and the cornerstone of manufacturing and marketing. Given that production is in a profound transformation stage with increasing global demand for products with specific uses tailored to customized needs, processes are also required to stay sync. This goal requires the adoption of advanced and pioneering technologies, and Virtual Commissioning (VC) is one of these tools that seek to achieve the best level of efficiency and benefit from the available assets. Virtual commissioning allows comprehensive testing of automation applications and provides a realistic training environment for operators even before the start of the factory, where these advanced technologies help to improve operations and retain knowledge, which leads to a reduction in operating time and a significant reduction in marketing time. There are three contributions in this thesis: firstly, systematic review methodology is applied to survey literature related to VC and it is found that the incorporation of virtual commissioning technology into manufacturing and automation is a large and huge field and has been widely discussed today in many recent research and studies. Then an industrial questionnaire is designed and conducted, totally 30 questionnaire forms are collected. Through data analysis, it is concluded that the virtual commissioning is a topic that has a lot of potential but is still in an early stage with some challenges to overcome, the application of virtual commissioning and its adoption by companies needs many capabilities, such as the availability of skills that must be available such as: competence skill of the employee on smart product, digital operation, IT infrastructure, data security, automation, data analytic, data exchange, application systems, and collaborative software. Finally, the key players in VC solutions and the comparison of their products are provided as a reference for potential applications.

  • 24.
    Allert, Anna-Lena
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Säfsten, Kristina
    School of Engineering, Jönköping University, Jönköping, Sweden.
    Business Support Agencies introducing Lean Production in SMEs - Does it make any difference?2014Conference paper (Refereed)
    Abstract [en]

    Many SMEs are implementing lean production in collaboration with a business support agency in order to improve their competitiveness. This research investigated whether improvement initiatives had the intended effect in some companies. A questionnaire was answered by employees in 26 SMEs. The result indicated experienced effect concerning leadership, communication and employee commitment, areas considered important for success in improvement initiatives,   and also progress in areas that characterise development towards lean. The result also indicated differences in experienced effect between managerial and non-managerial functions and between companies. 

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  • 25.
    Almaida Rodríguez, Germán
    et al.
    University of Skövde, School of Engineering Science.
    Cid Salmerón, Jose María
    University of Skövde, School of Engineering Science.
    Study of the influence of the angle between feed and flexibility direction on stability in milling: Experimental investigation of a theoretical prediction2023Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The study of this project has been carried out to analyse how the angle between feed direction and flexibility direction (𝜃 ) affects the milling process stability. Through this project, the aim is to determine whether the critical Depth of Cut (DOC) depends on 𝜃. In order to carry out this purpose, analytical and experimental results have been compared. The analytical calculations have been carried out to obtain the stability lobe diagram and a stability limit depending on 𝜃 , to compare them with four circular milling experiments. They increase continuously the DOC and also varies the Width of Cut (WOC), in addition different spindle speeds were utilized to perform them. The flexibility is fixed in the 𝑥 -axis and the feed direction changes continuously along the experiment, which allows the interaction between the critical DOC and all possible 𝜃 .The most relevant experiments were the second and third, as they showed the largest self-excited values. Moreover, it is determined that both analytical results correspond precisely, but it is considered that the experimental results do not match the analytical ones. No results are found that can be used to determine that 𝜃 influences the critical DOC. Furthermore, some results align with previous research in this field and some of them lead to future investigations.

  • 26.
    Almansa Fernández, Jesús Tomás
    et al.
    University of Skövde, School of Engineering Science.
    Vargas Maqueda, Juan Pablo
    University of Skövde, School of Health Sciences.
    Virtual commissioning with virtual reality2020Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The industry is nowadays going through a transformation in networking technologies which leads to what it is called Industry 4.0. This stage of the industry is arriving from the hand of the internet of things. Having connected all the elements within a factory allows to control and keep track of them telematically. Virtual commissioning is in charge of designing, testing and debugging the system before it is even built. This project tries to approach virtual reality to virtual commissioning and create the virtual model of a human in these simulated environments. Technology allows introducing human interaction for many purposes such as operator training. To do this project properly a methodology will be followed for the design and creation. Once the background, frame of reference and literature review are established, the development can start. The development of the project has taken place alongside Simumatik Open Emulation Platform, consisting of creating the body of a person, as simple as possible, following ergonomics, into this platform for commissioning purposes. The model will be able to interact with the virtual environment like robots, boxes, and sensors. To sum up, the complexity of the model will be limited to the inputs coming from the head and the hands. There exist infinite solutions for which position should be the rest of the body, therefore, this project aims to fix some variables to find valid solutions. Finally, the project achieved building a digital human model in which the main goal was building the arms that are estimated. The model is capable of interact with Simumatik´s environment that has been created specifically to show the functionalities of this project, being detected for sensors and robots of the system.

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  • 27.
    Almer Casino, Ana
    et al.
    University of Skövde, School of Engineering Science.
    Sempere Vicente, Miguel Ángel
    University of Skövde, School of Engineering Science.
    Autonomous medical robot2020Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Lack of healthcare assistance is one of the issues that European countries such as Sweden face due to the increase of the ageing phenomenon which leads to a higher demand for personnel in hospitals, basic attendance, and housing. Therefore, a tool is clearly required to fulfil these social needs. The thesis focuses on the elderly but especially on those with reduced mobility and develops a wheeled domestic mobile robot whose objective is to deliver their pills at the right time of the day. The main goal is the implementation of automatic drug delivery. The project presents a selection of the most suitable wheel-based robot, and a study and evaluation of different techniques and algorithms used for indoor positioning, navigation, facial recognition, and a communication interface between the patient and the robot.

    The robot used for the development of this thesis was the TurtleBot3 Burger and was evaluated upon a map created using the Hector SLAM method. Results showed that the Bluetooth technology (iBeacon), as well as the trilateration algorithm, are suitable choices for detecting a human in an indoor environment; a successful average drift error of 0.83 metres was obtained for indoor localization, and further results showed the facial recognition system achieved an accuracy of around 90%. It is concluded that the robot is capable of reaching and identifying the patient in an indoor environment, and so this project can be considered as the first step of implementation of a totally autonomous medical robot ready for domestic use.

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  • 28.
    Almirón Santa-Bárbara, Rafael
    et al.
    Department of Orthopaedic Surgery and Traumatology, Hospital de Antequera, Malaga, Spain ; School of Medicine, Universidad de Málaga, Spain.
    García Rivera, Francisco
    University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment.
    Lamb, Maurice
    University of Skövde, School of Informatics. University of Skövde, Informatics Research Environment. University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment.
    Víquez Da-Silva, Rodrigo
    Department of Orthopaedic Surgery and Traumatology, Hospital Universitario Virgen de la Victoria, Málaga, Spain.
    Gutiérrez Bedmar, Mario
    Preventive Medicine and Public Health Department, School of Medicine, University of Málaga, Spain ; Biomedical Research Institute of Malaga-IBIMA, Spain ; CIBERCV Cardiovascular Diseases, Carlos III Health Institute, Madrid, Spain.
    New technologies for the classification of proximal humeral fractures: Comparison between Virtual Reality and 3D printed models—a randomised controlled trial2023In: Virtual Reality, ISSN 1359-4338, E-ISSN 1434-9957, Vol. 27, no 3, p. 1623-1634Article in journal (Refereed)
    Abstract [en]

    Correct classification of fractures according to their patterns is critical for developing a treatment plan in orthopaedic surgery. Unfortunately, for proximal humeral fractures (PHF), methods for proper classification have remained a jigsaw puzzle that has not yet been fully solved despite numerous proposed classifications and diagnostic methods. Recently, many studies have suggested that three-dimensional printed models (3DPM) can improve the interobserver agreement on PHF classifications. Moreover, Virtual Reality (VR) has not been properly studied for classification of shoulder injuries. The current study investigates the PHF classification accuracy relative to an expert committee when using either 3DPM or equivalent models displayed in VR among 36 orthopaedic surgery residents from different hospitals. We designed a multicentric randomised controlled trial in which we created two groups: a group exposed to a total of 34 3DPM and another exposed to VR equivalents. Association between classification accuracy and group assignment (VR/3DPM) was assessed using mixed effects logistic regression models. The results showed VR can be considered a non-inferior technology for classifying PHF when compared to 3DPM. Moreover, VR may be preferable when considering possible time and resource savings along with potential uses of VR for presurgical planning in orthopaedics. 

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  • 29.
    Altrabulsy, Osama
    University of Skövde, School of Engineering Science.
    A Simulation-based Optimization Approach for Automated Vehicle Scheduling at Production Lines2019Independent thesis Advanced level (degree of Master (One Year)), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    The world becomes more integrated and sophisticated, especially in the birth of advanced technologies, which have influenced all life aspects. Automated systems could be considered an example of those aspects, which have been affected by recent changes in today’s life. The competition in the market is putting increasing pressure on different manufacturing organizations to find the best methods that enable them to stay up to date with the latest technologies in the industrial field. One of the most famous dilemmas that exist in this field is designing an efficient and flexible material handling system. This issue draws the attention of both decision-makers in different companies and software developers who put considerable effort into making that desired system real. Inclusive research needs to be performed to obtain such a system, and the most significant part of the research that requires special attention is the applied methodology.The approach to be adapted determines the degree of stability of a particular material handling system to function effectively in the case studied. Several methods are available and could be implemented to design that effective system such as meta-heuristic algorithms, and approaches that depend on simulation software tools. The latter approach, which is the simulation approach, seems to get increasing attention from developers of the industrial system since it plays a vital role in reducing the cost and preserving available resources. Besides, it helps predict future changes and scenarios of the system to be analyzed.In this project, a discrete-event simulation model was built for the proposed layout of the main shop floor owned by a Swedish manufacturing company. The corporation located in the south of Sweden, and it produces a vast range of manufacture of goods. The chosen methodology is a combination of lean, simulation, and optimization approaches. It has been implemented on the proposed layout in which material is handled into production lines by using automated guided vehicles (AGVs) as a means of transportation. The analysis of results shows potential benefits, where the production process became more efficient and organized since the operational cost has been reduced by decreasing the number of required vehicles. Moreover, the simulation approach facilitated testing new ideas and designing improved scenarios without the necessity to change the current state of the factory layout or disturbing the regular activities.

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  • 30.
    Amenabar, Leire
    et al.
    University of Skövde, School of Engineering Science.
    Carreras, Leire
    University of Skövde, School of Engineering Science.
    Augmented Reality Framework for Supporting and Monitoring Operators during Maintenance Operations in Industrial Environments2018Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In an ever-changing and demanding world where short assembly and innovation times are indispensable, it is of paramount importance to ensure that the machinery used throughout the whole process of a product are in their best possible condition. This guarantees that the performance of each machine will be optimal, and hence, the process times will be the shortest possible, while the best quality products are obtained. Moreover, having a machine in an impeccable status permits making the necessary changes to it, in order to fulfil the requirements that a more advanced or complex product may have. Maintenance operations and their corresponding trainings have historically been time-consuming, and a vast amount of information has been transmitted from an expert to a newer operator. This means that there has been the need of working with experienced operators to secure that a good service is provided. However, different technologies like augmented reality (AR) have been shown to have a positive impact in the support and monitoring of operators in industrial maintenance operations.The present project gathers information in regard to the framework of AR, with the aim of supporting and monitoring operators in industrial environments. The proposed method consists on the development of an artefact, which would lead to a possible improvement of the already existing solutions. It is believed that the development of an AR application could grant the necessary aid to any operator in maintenance operations. The result of this suggestion is an AR application which superimposes visual information on the physical equipment.

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  • 31.
    Amor Muñoz, Antonio
    et al.
    University of Skövde, School of Engineering Science.
    Fernandez Cranz, Matias
    University of Skövde, School of Engineering Science.
    SIMULATION AND EVALUATION OF WORK CONDITIONS OF HEALTHCARE PERSONNEL USING DHM TOOLS AND MOTION CAPTURE SYSTEMS2020Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Work-Related Musculoskeletal Disorders (WMSDs) are a common occupational health problem among healthcare workers. The emergence of new technologies such as motion capture offers a new approach to the study of the work conditions. This research studies the situation of nurses and surgeons both through the use of motion capture and traditional manual modelling of digital manikins. The research has been carried out through the study of six tasks, four of which performed by nurses and two by surgeons. Tasks have been selected after a literature review and interviews with surgeons and nurses. The six tasks have been evaluated using two software: Jack Tecnomatix, whose input was manual modelling of manikins following observational techniques; and IPS IMMA, whose input was motion capture files captured through Xsens Motion Trackers Awinda and processed with MVN Analyze. Results indicated that the tasks analysed were potentially harmful to workers, being the trunk and upper limb regions the ones that comprised higher levels of risk.

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  • 32.
    Amouzgar, Kaveh
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Metamodel Based Multi-Objective Optimization with Finite-Element Applications2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    As a result of the increase in accessibility of computational resources and the increase of computer power during the last two decades, designers are able to create computer models to simulate the behavior of complex products. To address global competitiveness, companies are forced to optimize the design of their products and production processes. Optimizing the design and production very often need several runs of computationally expensive simulation models. Therefore, integrating metamodels, as an efficient and sufficiently accurate approximate of the simulation model, with optimization algorithms is necessary. Furthermore, in most of engineering problems, more than one objective function has to be optimized, leading to multi-objective optimization(MOO). However, the urge to employ metamodels in MOO, i.e., metamodel based MOO (MB-MOO), is more substantial.Radial basis functions (RBF) is one of the most popular metamodeling methods. In this thesis, a new approach to constructing RBF with the bias to beset a priori by using the normal equation is proposed. The performance of the suggested approach is compared to the classic RBF and four other well-known metamodeling methods, in terms of accuracy, efficiency and, most importantly, suitability for integration with MOO evolutionary algorithms. It has been found that the proposed approach is accurate in most of the test functions, and it was the fastest compared to other methods. Additionally, the new approach is the most suitable method for MB-MOO, when integrated with evolutionary algorithms. The proposed approach is integrated with the strength Pareto evolutionary algorithm (SPEA2) and applied to two real-world engineering problems: MB-MOO of the disk brake system of a heavy truck, and the metal cutting process in a turning operation. Thereafter, the Pareto-optimal fronts are obtained and the results are presented. The MB-MOO in both case studies has been found to be an efficient and effective method. To validate the results of the latter MB-MOO case study, a framework for automated finite element (FE) simulation based MOO (SB-MOO) of machining processes is developed and presented by applying it to the same metal cutting process in a turning operation. It has been proved that the framework is effective in achieving the MOO of machining processes based on actual FE simulations.

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  • 33.
    Amouzgar, Kaveh
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Bandaru, Sunith
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Andersson, Tobias J.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Ng, Amos H. C.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    A framework for simulation based multi-objective optimization and knowledge discovery of machining process2018In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 98, no 9-12, p. 2469-2486Article in journal (Refereed)
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  • 34.
    Amouzgar, Kaveh
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Bandaru, Sunith
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Andersson, Tobias J.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Ng, Amos H. C.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Metamodel based multi-objective optimization of a turning process by using finite element simulationManuscript (preprint) (Other academic)
    Abstract [en]

    This study investigates the advantages and potentials of the metamodelbased multi-objective optimization (MOO) of a turning operation through the application of finite element simulations and evolutionary algorithms to a metal cutting process. The objectives are minimizing the interface temperature and tool wear depth obtained from FE simulations using DEFORM2D software, and maximizing the material removal rate. Tool geometry and process parameters are considered as the input variables. Seven metamodelling methods are employed and evaluated, based on accuracy and suitability. Radial basis functions with a priori bias and Kriging are chosen to model tool–chip interface temperature and tool wear depth, respectively. The non-dominated solutions are found using the strength Pareto evolutionary algorithm SPEA2 and compared with the non-dominated front obtained from pure simulation-based MOO. The metamodel-based MOO method is not only advantageous in terms of reducing the computational time by 70%, but is also able to discover 31 new non-dominated solutions over simulation-based MOO.

  • 35.
    Amouzgar, Kaveh
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment.
    Bandaru, Sunith
    University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment.
    Andersson, Tobias
    University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment.
    Ng, Amos H. C.
    University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment.
    Metamodel based multi-objective optimization of a turning process by using finite element simulation2020In: Engineering optimization (Print), ISSN 0305-215X, E-ISSN 1029-0273, Vol. 52, no 7, p. 1261-1278Article in journal (Refereed)
    Abstract [en]

    This study investigates the advantages and potentials of the metamodelbased multi-objective optimization (MOO) of a turning operation through the application of finite element simulations and evolutionary algorithms to a metal cutting process. The objectives are minimizing the interface temperature and tool wear depth obtained from FE simulations using DEFORM2D software, and maximizing the material removal rate. Tool geometry and process parameters are considered as the input variables. Seven metamodelling methods are employed and evaluated, based on accuracy and suitability. Radial basis functions with a priori bias and Kriging are chosen to model tool–chip interface temperature and tool wear depth, respectively. The non-dominated solutions are found using the strength Pareto evolutionary algorithm SPEA2 and compared with the non-dominated front obtained from pure simulation-based MOO. The metamodel-based MOO method is not only advantageous in terms of reducing the computational time by 70%, but is also able to discover 31 new non-dominated solutions over simulation-based MOO.

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  • 36.
    Amouzgar, Kaveh
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Bandaru, Sunith
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Ng, Amos H. C.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Radial basis functions with a priori bias as surrogate models: A comparative study2018In: Engineering applications of artificial intelligence, ISSN 0952-1976, E-ISSN 1873-6769, Vol. 71, p. 28-44Article in journal (Refereed)
    Abstract [en]

    Radial basis functions are augmented with a posteriori bias in order to perform robustly when used as metamodels. Recently, it has been proposed that the bias can simply be set a priori by using the normal equation, i.e., the bias becomes the corresponding regression model. In this study, we demonstrate the performance of the suggested approach (RBFpri) with four other well-known metamodeling methods; Kriging, support vector regression, neural network and multivariate adaptive regression. The performance of the five methods is investigated by a comparative study, using 19 mathematical test functions, with five different degrees of dimensionality and sampling size for each function. The performance is evaluated by root mean squared error representing the accuracy, rank error representing the suitability of metamodels when coupled with evolutionary optimization algorithms, training time representing the efficiency and variation of root mean squared error representing the robustness. Furthermore, a rigorous statistical analysis of performance metrics is performed. The results show that the proposed radial basis function with a priori bias achieved the best performance in most of the experiments in terms of all three metrics. When considering the statistical analysis results, the proposed approach again behaved the best, while Kriging was relatively as accurate and support vector regression was almost as fast as RBFpri. The proposed RBF is proven to be the most suitable method in predicting the ranking among pairs of solutions utilized in evolutionary algorithms. Finally, the comparison study is carried out on a real-world engineering optimization problem.

  • 37.
    Amouzgar, Kaveh
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment.
    Ng, Amos H. C.
    University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment. Division of Industrial Engineering and Management, Uppsala University, Sweden.
    Ljustina, Goran
    Volvo Car Corporation, ME PS Research and Technology, Skövde, Sweden.
    Optimizing index positions on CNC tool magazines considering cutting tool life and duplicates2020In: Procedia CIRP, E-ISSN 2212-8271, Vol. 93, p. 1508-1513Article in journal (Refereed)
    Abstract [en]

    Minimizing the non-machining time of CNC machines requires optimal positioning of cutting tools on indexes (stations) of CNC machine turret magazine. This work presents a genetic algorithm with a novel solution representation and genetic operators to find the best possible index positions while tool duplicates and tools life are taken in to account during the process. The tool allocation in a machining process of a crankshaft with 10 cutting operations, on a 45-index magazine, is optimized for the entire life of the tools on the magazine. The tool-indexing time is considerably reduced compared to the current index positions being used in an automotive factory. 

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  • 38.
    Amouzgar, Kaveh
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment. Division of Industrial Engineering and Management, Uppsala University.
    Nourmohammadi, Amir
    University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment.
    Ng, Amos H. C.
    University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment. Division of Industrial Engineering and Management, Uppsala University.
    Multi-objective optimisation of tool indexing problem: a mathematical model and a modified genetic algorithm2021In: International Journal of Production Research, ISSN 0020-7543, E-ISSN 1366-588X, Vol. 59, no 12, p. 3572-3590Article in journal (Refereed)
    Abstract [en]

    Machining process efficiencies can be improved by minimising the non-machining time, thereby resulting in short operation cycles. In automatic-machining centres, this is realised via optimum cutting tool allocation on turret-magazine indices – the “tool-indexing problem”. Extant literature simplifies TIP as a single-objective optimisation problem by considering minimisation of only the tool-indexing time. In contrast, this study aims to address the multi-objective optimisation tool indexing problem (MOOTIP) by identifying changes that must be made to current industrial settings as an additional objective. Furthermore, tool duplicates and lifespan have been considered. In addition, a novel mathematical model is proposed for solving MOOTIP. Given the complexity of the problem, the authors suggest the use of a modified strength Pareto evolutionary algorithm combined with a customised environment-selection mechanism. The proposed approach attained a uniform distribution of solutions to realise the above objectives. Additionally, a customised solution representation was developed along with corresponding genetic operators to ensure the feasibility of solutions obtained. Results obtained in this study demonstrate the realization of not only a significant (70%) reduction in non-machining time but also a set of tradeoff solutions for decision makers to manage their tools more efficiently compared to current practices. 

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  • 39.
    Amouzgar, Kaveh
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. Product Development Department, School of Engineering, Jönköping University, Jönköping, Sweden.
    Strömberg, Niclas
    Department of Mechanical Engineering, School of Science and Technology, University of Örebro, Sweden.
    Radial basis functions as surrogate models with a priori bias in comparison with a posteriori bias2017In: Structural and multidisciplinary optimization (Print), ISSN 1615-147X, E-ISSN 1615-1488, Vol. 55, no 4, p. 1453-1469Article in journal (Refereed)
    Abstract [en]

    In order to obtain a robust performance, the established approach when using radial basis function networks (RBF) as metamodels is to add a posteriori bias which is defined by extra orthogonality constraints. We mean that this is not needed, instead the bias can simply be set a priori by using the normal equation, i.e. the bias becomes the corresponding regression model. In this paper we demonstrate that the performance of our suggested approach with a priori bias is in general as good as, or even for many test examples better than, the performance of RBF with a posteriori bias. Using our approach, it is clear that the global response is modelled with the bias and that the details are captured with radial basis functions. The accuracy of the two approaches are investigated by using multiple test functions with different degrees of dimensionality. Furthermore, several modeling criteria, such as the type of radial basis functions used in the RBFs, dimension of the test functions, sampling techniques and size of samples, are considered to study their affect on the performance of the approaches. The power of RBF with a priori bias for surrogate based design optimization is also demonstrated by solving an established engineering benchmark of a welded beam and another benchmark for different sampling sets generated by successive screening, random, Latin hypercube and Hammersley sampling, respectively. The results obtained by evaluation of the performance metrics, the modeling criteria and the presented optimal solutions, demonstrate promising potentials of our RBF with a priori bias, in addition to the simplicity and straight-forward use of the approach.

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  • 40.
    Ander, Jenny
    et al.
    University of Skövde, School of Engineering Science.
    Johansson, Matilda
    University of Skövde, School of Engineering Science.
    Utveckling av laddhandske för laddbara fordon2018Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    During the autumn term of 2017, Jenny Ander and Matilda Johansson have performed a project in collaboration with Sea Ice AB in the course Degree Project in Integrated Product Development at the University of Skövde. Sea Ice AB is working on developing charging infrastructure systems for rechargeable vehicles with focus on end-user benefits, high quality and increasing sustainability for the environment.The company is aiming to grow larger in the market and, in the future, be able to deliver attractive products and services, which in this project has involved the development of a new vehicle connector for rechargeable vehicles.

    During the project, vehicle connectors and CEE-plugs have been compared with each other, focusing on its internal components. The pre-study is based on literature studies where standards have been studied, ergonomics and user studies, questionnaires, electrical measurements, but mainly disassembly and analysis of vehicle connectors and CEE-plugs.

    After the pre-study, the concept development of the vehicle connector began with design methods, FEA-analyzes, CAD and clay modeling, concept screening and detail design. The concept development resulted in a complete final concept for both internal components, but also an external shell with ergonomic grip surfaces and angles.

    The final concept has been compared to the requirement specification and achieved the requirements set for the project, with some reservation for continued development. The vehicle connector has a unique and appealing appearance and meets the demands that both users and Sea Ice AB whished for.

  • 41.
    Andersen, Ann-Louise
    et al.
    Industrial Product Development, Production and Design, School of Engineering, Jönköping University, Sweden ; Department of Materials and Production, Aalborg University, Denmark.
    Rösiö, Carin
    University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment. Industrial Product Development, Production and Design, School of Engineering, Jönköping University, Sweden.
    Continuing Engineering Education in Changeable and Reconfigurable Manufacturing – Implications of Problem-Based Learning in Industrial Practice2023In: International Journal of Engineering Education, ISSN 0949-149X, Vol. 39, no 5, p. 1118-1130Article in journal (Refereed)
    Abstract [en]

    Increasingly volatile and complex manufacturing environments make the continuous development of engineering professionals’ knowledge and competences in changeable and reconfigurable manufacturing a major source of competitiveness in manufacturing companies. Enablers of this include modular and platform-based product and manufacturing system design, as well as industry 4.0 related technologies and digitalisation. Therefore, this paper focuses on Continuing Engineering Education (CEE) in changeable and reconfigurable manufacturing and investigates the implications of applying a university-industry collaborative approach to Problem-based Learning (PBL) for CEE in company-settings. The paper builds on a four-year CEE initiative from Swedish manufacturing industry and includes insights from implementing a CEE course in changeable manufacturing, which was designed based on PBL principles and run as an industry-university cooperation for four consecutive years. Implications addressed in the paper relates to (1) PBL as a suitable approach for CEE, (2) Research transfer to industry through PBL-based CEE, and (3) industry-university collaboration for CEE, which provides valuable insights on how to conduct successful CEE in knowledge fields that are fast evolving in order to enable fast industry transitions. # 2023 TEMPUS Publications.

  • 42.
    Andersson, Daniel
    et al.
    University of Skövde, School of Engineering Science. andersson.daniel89@gmail.com.
    Andersson, David
    University of Skövde, School of Engineering Science. davdii_@live.com.
    Produktionseffektivisering med hjälp av flödessimulering och förbättringsarbete2018Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    AB Furhoffs Rostfria is a company with its base in Skövde. They are specialists in the manufacturing of stainless-steel parts, such as plumbing products, floor wells and sinks. In addition to manufacturing their own products, the company also has a subcontract to manufacture other companies’ products.

    The department where this bachelor thesis will be conducted has a subcontract to manufacturing radar cones and treats only the production of the most frequent manufactured radar cones. The department consists of seven manufacturing steps and three additional steps for one of the details.

    The purpose of the bachelor thesis is to create a simulation model that shows how potential improvement proposals would meet the expected increase of the order intake of the radar cones by streamlining the current production flow. In order to achieve this, a simulation model has been created in which the improvement proposals have been implemented. The improvement proposals that have been tested are based on the data that has been collected through production engineering methods.

    The frame of references describes the theory that constitutes the foundation for the chosen methods. In addition, areas within discrete event simulation, lean production and improvement work have been studied from other works in the literature review. These areas can in some way relate to the work and conclusions of this project.

    The empirical study was conducted by using observations according to genchi genbutsu, conversations and interviews with operators, spaghetti diagrams of the operators and the product flow as well as time studies according to the continuous method. These methods have formed the basis for both the creation of the simulation model, where the current situation is reflected, and for the development of the future state simulation model. The future state simulation model shows the implementation of the improvement proposals that increases efficiency and production volume throughout the system.

    The empirical study resulted in a visual overview of the production flow, standard times, the identification of waste as well as improvement proposals. When all the improvement proposals were implemented, the hourly production was increased by 26.6% and the lead time was reduced by 21.1%. With these improvements, the company can increase their production and profit significantly.

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  • 43.
    Andersson, Emil
    University of Skövde, School of Engineering Science.
    Optimization and re-design of a wheel hub to reduce unsprung mass of a rallycross car2018Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Wheel Hub of a rallycross car is analysed to reduce the unsprung mass of the car. The problem statement is to mainly focus on the unsprung mass related to the suspension, and more specifically on the Wheel Hub. One of the objectives of the suspension system of a car is to damping the movement of the car. This is an important area when designing a vehicle, and especially a race car due to the extreme conditions that may result in reduced traction and loose of confidence for the driver. A theoretical model is performed to demonstrate the importance of a low unsprung mass and to illustrate how it affects the vehicle-handling. A process to evaluate the current Wheel Hub and decision to re-design the Wheel Hub is performed, and the parts are analysed using the Finite Element Method to verify the design and material selection. Vehicle dynamics of the car is analysed to calculate the acting forces. Optimization of the design is performed by using Computer Aided Engineering. The re-designed Wheel Hub presented as the result of this project with a Brake Disk Adapter integrated in Hub. This design reduces the number of parts, and the unsprung mass up to 25% without any effects on suspension geometry or other parts of the car.

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  • 44.
    Andersson, Erica
    et al.
    University of Skövde, School of Engineering Science.
    Fritz, Sophia
    University of Skövde, School of Engineering Science.
    Möjligheter med kollaborativa robotar i slutmonteringen på Volvo GTO: Urvalsprinciper för en coaktiv implementation2017Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Collaborative robots are a new technology that offers flexibility and precision for manual tasks that previously have been difficult to automate. Volvo Group Trucks Operations engine plant in Skövde is a pilot plant where new technical solutions are tested before it is implemented in the rest of the company. The company sees that collaborative robots can provide benefits for the operator’s ergonomics and improved process and product quality in the final assembly of 13L truck engines. The purpose of the project is to investigate the possibilities of collaborative robots in the final assembly as well as to give a deeper understanding of the robot's field of application. The project has been defined to Universal Robots, preparation, preassembly and final assembly for 13L truck engines. The objectives are to develop distinctive features for a coactive implementation, to develop a basic analysis and to co-locate possible tasks into a coactive station and if co-location is not possible provide recommendations on minimal features that should be included in the collaborative robot.

    To achieve the goals, a systematic method has been prepared to ensure that the project addresses to the problem and the objectives. Knowledge has been gathered through literature studies and reference frameworks to form the basis for the practical work. All operations in areas 1-4 on the production line have been identified and analyzed to find coactive features, which has been the basis for developing a basic analysis. Several of the features that have been identified from the production line are consistent with what a Universal Robot can perform. That these features match, shows that a collaborative robot is possible to implement in the final assembly. The basic analysis has then been used to co-locate two coactive stations in the production line.

    The basic analysis could be used as a basis for the company in the implementation of collaborative robots. As technology of collaborative robots develops, the features and basic analysis needs to be updated.

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  • 45.
    Andersson, Johanna
    et al.
    University of Skövde, School of Engineering Science.
    Marwén, Kristin
    University of Skövde, School of Engineering Science.
    Analys av tunn rostfri hylsa i klämförband2020Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The examined sleeve is made of material AISI 440B and has the purpose of acting as a reinforced wear surface in a 3D applicator for example sealants and glue. The sleeve should prevent wear in the swivel mechanism of the applicator, and is therefore hardened to obtain a hard surface which can resist the abrasive substances flowing through the applicator. The sleeve has been investigated in order to find critical points that can be optimized for further competitive product. An independent analysis of the construction of the sleeve was therefore made without regard to previous work. Since the information regarding the use was scarce, the work was limited from studies of wear and transportation. Therefore, only manufacturing, assembly and construction were studied.

    The causes of failure were proved to be very individual as it was difficult to determine when and how often a failure could occur. It was unknown how long the product has been used as well as what kind of materials has flown through the 3D applicator in different industries. This meant that the construction of the sleeve was examined through methods such as "walk to gemba", "Finite Element Method" and visual inspection. FE analyse examined the impact of the assembly process on the strength and provides an overview of the stress distributions in the sleeve. The visual inspection was applied to obtain an understanding of the origin of the crack in the sleeve as well as mapping the crack propagation.

    The result of investigation and analysis showed that the following critical parameters were detected:

    • The literature study showed that hardening and machining of the sleeve is critical in different ways for the strength
    • The roundness of the sleeve risks varying impermissibly during assembly
    • The adhesive risks to not performing any function
    • The cracks could be derived to start in the holes of the examined sleeve.
    • Causes of cracking cannot be determined.
    • The FE analysis of the assembly process did not indicate any weakening in the construction and no stresses were calculated to exceed the breaking limit.

    The concluding discussion resulted in a number of proposals for further work. Some suggestions (among other things) were to investigate the effect of roundness in interference-fit, exchange of materials and tribology.

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  • 46.
    Andersson Lassila, Andreas
    University of Skövde, School of Engineering Science.
    Meta model-based multi-objective optimization of laser welded dissimilar material joints for battery components2024Independent thesis Advanced level (degree of Master (One Year)), 12 credits / 18 HE creditsStudent thesis
    Abstract [en]

    During the assembly process of battery packs for electric vehicles, it is crucial to ensure that the cell-to-busbar joints can be produced with high quality, good reliability, and with minimal impact on the individual battery cells. This thesis project investigates the influence of different process parameters on the joint quality for laser welded dissimilar material cell-to-busbar joints. Nickel plated copper and steel plates, joined in an overlap configuration, are used as a simplified geometry, representing a cell-to-busbar joint. By the utilization of artificial neural network-based meta models, trained on numerical results from computational fluid dynamics simulations of the laser welding process, the joint quality is predicted and evaluated. The present thesis investigates how a set of optimized process parameters can be identified for the considered laser welded dissimilar material cell-to-busbar joints, in order to simultaneously maximize the interface width for the joints, and minimize the formation of undercuts and resulting in-process temperatures. NSGA-II is used to efficiently search for trade-off solutions, in an meta model-based multi-objective optimization approach, where the meta models are used to approximate the objectives, corresponding to the joint quality obtained from computational fluid dynamics simulations. With this, the time for one objective evaluation is reduced from approximately 9 hours, when the objectives are evaluated directly from computational fluid dynamics simulations, to only tenths of a second. With the proposed optimization approach, the Pareto-optimal front of trade-off solutions is identified, leading to the selection of three optimal solutions for validation. The validity of the proposed optimization approach, and the selected optimal solutions, are confirmed by means of both physical laser welding experiments and computational fluid dynamics simulations. It is shown that the selected optimal solutions, corresponding to three parameter setups, can be used to produce joints with large interface width and low in-process temperatures, without achieving a full penetration in the lower plate of the joint.

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  • 47.
    Andersson Lassila, Andreas
    et al.
    University of Skövde, School of Engineering Science.
    Folcke, Marcus
    University of Skövde, School of Engineering Science.
    Numerical and experimental analysis of adhesively bonded T-joints: Using a bi-material interface and cohesive zone modelling2018Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    With increasing climate change the automotive industry is facing increasing demands regarding emissions and environmental impact. To lower emissions and environmental impact the automotive industry strives to increase the efficiency of vehicles by for example reducing the weight. This can be achieved by the implementation of lightweight products made of composite materials where different materials must be joined. A key technology when producing lightweight products is adhesive joining.

    In an effort to expand the implementations of structural adhesives Volvo Buses wants to increase their knowledge about adhesive joining techniques. This thesis is done in collaboration with Volvo Buses and aims to increase the knowledge about numerical simulations of adhesively bonded joints. A numerical model of an adhesively bonded T-joint is presented where the adhesive layer is modelled using the Cohesive Zone Model. The experimental extraction of cohesive laws for adhesives is discussed and implemented as bi-linear traction-separation laws. Experiments of the T-joint for two different load cases are performed and compared to the results of the numerical simulations. The experimental results shows a similar force-displacement response as for the results of the numerical simulations. Although there were deviations in the maximum applied load and for one load case there were deviations in the behavior after the main load drop. The deviations between numerical and experimental results are believed to be due to inaccurate material properties for the adhesive, the use of insufficient bi-linear cohesive laws, the occurrence of a combination of adhesive and cohesive fractures during the experiments and dissimilar effective bonding surface areas in the numerical model and the physical specimens.

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    Numerical and experimental analysis of adhesively bonded T-joints
  • 48.
    Andersson Lassila, Andreas
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment.
    Lönn, Dan
    University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment.
    Andersson, Tobias J.
    University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment.
    Wang, Wei
    University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment.
    Ghasemi, Rohollah
    University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment.
    Effects of different laser welding parameters on the joint quality for dissimilar material joints for battery applications2024In: Optics and Laser Technology, ISSN 0030-3992, E-ISSN 1879-2545, Vol. 177, article id 111155Article in journal (Refereed)
    Abstract [en]

    For battery pack assemblies, it is crucial that the laser welded cell-to-busbar joints demonstrate both high mechanical strength and minimal electrical resistance. The present study investigates the effect of different laser welding parameters, on the mechanical strength, electrical resistance, porosity formation and joint microstructure, for dissimilar material cell-to-busbar joints. Laser welding experiments are performed, on thin nickel-plated copper and steel plates. The plates are joined in an overlap configuration, using laser beam wobbling and power modulation. Both circular and sinusoidal laser beam wobbling are used as selected strategies to increase the interface width of the joints, where also a comparison is made between the two methods. The joint quality is evaluated using joint geometry analysis, shear strength tests, computed tomography scanning and electrical resistance measurements. The results show that circular laser beam wobbling gives a larger joint shear strength compared with sinusoidal laser beam wobbling. In addition, it is observed that both the total pore volume and material mixing are significantly increased with increasing laser power and wobbling frequency for circular laser beam wobbling. However, for the sinusoidal laser beam wobbling the wobbling frequency does not show a significant impact on the total pore volume.

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  • 49.
    Andersson Lassila, Andreas
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment.
    Svensson, Daniel
    University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment.
    Wang, Wei
    University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment.
    Andersson, Tobias
    University of Skövde, School of Engineering Science. University of Skövde, Virtual Engineering Research Environment.
    Numerical evaluation of cutting strategies for thin-walled parts2024In: Scientific Reports, E-ISSN 2045-2322, Vol. 14, no 1, article id 1459Article in journal (Refereed)
    Abstract [en]

    Static form errors due to in-process deflections is a major concern in flank milling of thin-walled parts. To increase both productivity and part geometric accuracy, there is a need to predict and control these form errors. In this work, a modelling framework for prediction of the cutting force-induced form errors, or thickness errors, during flank milling of a thin-walled workpiece is proposed. The modelled workpiece geometry is continuously updated to account for material removal and the reduced stiffness matrix is calculated for nodes in the engagement zone. The proposed modelling framework is able to predict the resulting thickness errors for a thin-walled plate which is cut on both sides. Several cutting strategies and cut patterns using constant z-level finishing are studied. The modelling framework is used to investigate the effect of different cut patterns, machining allowance, cutting tools and cutting parameters on the resulting thickness errors. The framework is experimentally validated for various cutting sequences and cutting parameters. The predicted thickness errors closely correspond to the experimental results. It is shown from numerical evaluations that the selection of an appropriate cut pattern is crucial in order to reduce the thickness error. Furthermore, it is shown that an increased machining allowance gives a decreased thickness error for thin-walled plates.

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  • 50.
    Andersson, Linna
    et al.
    University of Skövde, School of Engineering Science.
    Bergström, Ellinor
    University of Skövde, School of Engineering Science.
    Utveckling av portabel mobilhållare som hjälpmedel vid e-möten och distansundervisning2018Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of the degree project is to methodically develop a product that will serve as an accessory for a smartphones during documentation. A preliminary study was done to gain a deeper knowledge and understanding of digital meeting rooms, how a camera works and what resolution is. With the information gathered, the work went on to a literature study on additive manufacturing, how a product can be designed and printed digitally. The preliminary study resulted in a requirement specification that formed the basis for concept generation and later a result.

     The result was a prototype of a lightweight and portable holder for smartphones that is 3D-printable and made out of only one material, which provides good recycling opportunities for the user. The prototype fulfills most of the sub-goals that were set up early and the main purpose of the project could also be met.

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