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  • 1.
    Abril, Daniel
    et al.
    IIIA, Institut d'Investigació en Intelligència Artificial – CSIC, Consejo Superior de Investigaciones Científicas, Bellaterra, Spain / UAB, Universitat Autónoma de Barcelona, Bellaterra, Spain.
    Navarro-Arribas, Guillermo
    DEIC, Dep. Enginyeria de la Informació i de les Comunicacions, UAB, Universitat Autònoma de Barcelona, Bellaterra, Spain.
    Torra, Vicenç
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre. IIIA, Institut d'Investigació en Intelligència Artificial – CSIC, Consejo Superior de Investigaciones Científicas, Bellaterra, Spain.
    Spherical Microaggregation: Anonymizing Sparse Vector Spaces2015In: Computers & security (Print), ISSN 0167-4048, E-ISSN 1872-6208, Vol. 49, p. 28-44Article in journal (Refereed)
    Abstract [en]

    Unstructured texts are a very popular data type and still widely unexplored in the privacy preserving data mining field. We consider the problem of providing public information about a set of confidential documents. To that end we have developed a method to protect a Vector Space Model (VSM), to make it public even if the documents it represents are private. This method is inspired by microaggregation, a popular protection method from statistical disclosure control, and adapted to work with sparse and high dimensional data sets.

  • 2.
    Adamson, Göran
    et al.
    University of Skövde, The Virtual Systems Research Centre. University of Skövde, School of Technology and Society.
    Holm, Magnus
    University of Skövde, The Virtual Systems Research Centre. University of Skövde, School of Technology and Society.
    Wang, Lihui
    University of Skövde, The Virtual Systems Research Centre. University of Skövde, School of Technology and Society.
    Moore, Philip
    University College Falmouth, United Kingdom.
    Adaptive Assembly Feature Based Function Block Control of Robotic Assembly Operations2012In: The 13th Mechatronics Forum International Conference Proceedings: Vol. 1/3 / [ed] Rudolf Scheidl & Bernhard Jakoby, Linz: TRAUNER Verlag, 2012, p. 8-13Conference paper (Refereed)
    Abstract [en]

    Many manufacturing systems are exposed to a variety of unforeseen changes, negatively restricting their performances. External variations depending on market demand (e.g. changes in design, quantity and product mix) and internal variations in production capability and flexibility (e.g. equipment breakdowns, missing/worn/broken tools, delays and express orders) all contribute to an environment of uncertainty. In these dynamically changing environments, adaptability is a key feature for manufacturing systems to be able to perform at a maximum level, while keeping unscheduled downtime to a minimum. Targeting manufacturing equipment adaptability, this paper reports an assembly feature (AF) based approach for robotic assembly, using IEC 61499 compliant Function Blocks (FBs). Through the use of a network of event-driven FBs, an adaptive controller system for an industrial gantry robot’s assembly operations has been designed, implemented and tested. Basic assembly operations have been mapped as AFs into Assembly Feature Function Blocks (AF-FBs). Through their combination in FB networks, they can be aggregated to perform higher level assembly tasks. The AF-FBs dynamic execution and behavior can be adaptively controlled through embedded eventdriven algorithms, enabling the ability of adaptive decisions to handle unforeseen changes in the runtime environment.

  • 3.
    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. Kungliga Tekniska Högskolan, Stockholm (KTH).
    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, The University of Texas at San Antonio, U.S.A., 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.

  • 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. Kungliga Tekniska Högskolan, Stockholm (KTH).
    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.
    Function Block Approach for Adaptive Robotic Control in Virtual and Real Environments2014In: Proceedings of the 14th Mechatronics Forum International Conference / [ed] Leo J. De Vin and 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.

  • 5.
    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.

  • 6.
    Al Mamun, Abdullah
    et al.
    Division of Software Engineering Chalmers University of Technology and University of Gothenburg, Gothenburg, Sweden.
    Berger, Christian
    Division of Software Engineering Chalmers University of Technology and University of Gothenburg, Gothenburg, Sweden.
    Hansson, Jörgen
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Explicating, Understanding and Managing Technical Debt from Self-Driving Miniature Car Projects2014In: Proceedings 2014 6th IEEE International Workshop on Managing Technical Debt: MTD 2014, Los Alamitos, CA: IEEE Computer Society, 2014, p. 11-18Conference paper (Refereed)
    Abstract [en]

    Technical debt refers to various weaknesses in the design or implementation of a system resulting from trade-offs during software development usually for a quick release. Accumulating such debt over time without reducing it can seriously hamper the reusability and maintainability of the software. The aim of this study is to understand the state of the technical debt in the development of self-driving miniature cars so that proper actions can be planned to reduce the debt to have more reusable and maintainable software. A case study on a selected feature from two self-driving miniature car development projects is performed to assess the technical debt. Additionally, an interview study is conducted involving the developers to relate the findings of the case study with the possible root causes. The result of the study indicates that "the lack of knowledge" is not the primary reason for the accumulation of technical debt from the selected code smells. The root causes are rather in factors like time pressure followed by issues related to software/hardware integration and incomplete refactoring as well as reuse of legacy, third party, or open source code.

  • 7.
    Alenljung, Beatrice
    et al.
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Andreasson, Rebecca
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre. Department of Information Technology, Visual Information & Interaction. Uppsala University, Uppsala, Sweden.
    Billing, Erik A.
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Lindblom, Jessica
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Lowe, Robert
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    User Experience of Conveying Emotions by Touch2017In: Proceedings of the 26th IEEE International Symposium on Robot and Human Interactive Communication (RO-MAN), IEEE, 2017, p. 1240-1247Conference paper (Refereed)
    Abstract [en]

    In the present study, 64 users were asked to convey eight distinct emotion to a humanoid Nao robot via touch, and were then asked to evaluate their experiences of performing that task. Large differences between emotions were revealed. Users perceived conveying of positive/pro-social emotions as significantly easier than negative emotions, with love and disgust as the two extremes. When asked whether they would act differently towards a human, compared to the robot, the users’ replies varied. A content analysis of interviews revealed a generally positive user experience (UX) while interacting with the robot, but users also found the task challenging in several ways. Three major themes with impact on the UX emerged; responsiveness, robustness, and trickiness. The results are discussed in relation to a study of human-human affective tactile interaction, with implications for human-robot interaction (HRI) and design of social and affective robotics in particular. 

  • 8.
    Aliahmadipour, Laya
    et al.
    Department of Applied Mathematics, Faculty of Mathematics and Computer, Shahid Bahonar University of Kerman, Kerman, Iran.
    Torra, Vicenç
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Eslami, Esfandiar
    Department of Pure Mathematics, Faculty of Mathematics and Computer, Shahid Bahonar University of Kerman, Kerman, Iran.
    Eftekhari, Mahdi
    Department of Computer Engineering, Faculty of Engineering, Shahid Bahonar University of Kerman, Kerman, Iran.
    A definition for hesitant fuzzy partitions2016In: International Journal of Computational Intelligence Systems, ISSN 1875-6891, E-ISSN 1875-6883, Vol. 9, no 3, p. 497-505Article in journal (Refereed)
    Abstract [en]

    In this paper, we define hesitant fuzzy partitions (H-fuzzy partitions) to consider the results of standard fuzzy clustering family (e.g. fuzzy c-means and intuitionistic fuzzy c-means). We define a method to construct H-fuzzy partitions from a set of fuzzy clusters obtained from several executions of fuzzy clustering algorithms with various initialization of their parameters. Our purpose is to consider some local optimal solutions to find a global optimal solution also letting the user to consider various reliable membership values and cluster centers to evaluate her/his problem using different cluster validity indices.

  • 9.
    Andersson, Martin
    University of Skövde, School of Humanities and Informatics.
    SANDBUNKERSEGMENTERING FÖR SMARTPHONES: Automatisk positionsuppskattning av sandbunkrar för smartphone som golfcaddie2011Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Ett av många nya användningsområden för smartphones är att använda dem som

    caddie på golfbanan. Golfaren kan få hjälp med avståndsuppskattning till intressanta

    punkter på banan genom att dessa punkter programmeras in och jämförs med

    smartphonens inbyggda positioneringssystem. Den här rapporten visar hur det med en

    bildsegmenteringsalgoritm går att slippa det manuella arbetet med att lägga in

    positioner för sandbunkrar på golfbanan. Algoritmen som tagits fram arbetar på

    satellitbilder som smartphonen kan ladda ned via dess Internetanslutning. Golfaren

    kan i ett tänkt scenario ge sig ut på en godtycklig golfbana och få hjälp med

    avståndsbedömning enbart med hjälp av satellitbilder och smartphonens gps. I snitt

    hittar den framtagna segmenteringsalgoritmen cirka 70 % av sandbunkrarna på en

    satellitbild, en siffra som i en verklig applikation skulle behöva ökas och förslag på

    hur detta kan göras ges i slutet av rapporten. Tre olika upplösningar på satellitbilderna

    har utvärderats och testkörts i en nyare smartphone. Även om den högsta

    upplösningen används tar en hel golfbana endast cirka 15 sekunder att segmentera

    vilket bör hinnas med under loppet av en vanlig golfrunda som i regel tar 3 till 5

    timmar.

    I ett vidare perspektiv går det att tänka sig helt andra tillämpningar där det finns

    behov av positionsuppskattning av objekt i en satellitbild i sin smartphone. Det bör på

    ett förhållandevis enkelt sätt gå att utvidga slutsatserna som dragits i rapporten till att

    gälla annat än enbart sandbunkrar, t.ex. sjöar, fält, åkrar och givetvis andra delar av

    golfbanan som vattenhinder och greener.

  • 10.
    Andersson, Tommy
    University of Skövde, School of Humanities and Informatics.
    Avvaktande AJAX- anrop: En avlastningsteknik för 3G-nätet2012Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Den ökade användningen av nätuppkopplade mobilapplikationer har resulterat i en överbelastning i 3G-nätet. Förslag för att avlasta nätet har bland annat varit genom alternativa uppkopplingar, vilket innebär en uppoffring av 3G-nätets tillgänglighet. Detta leder till frågor om andra avlastningsmetoder. Arbetets målsättning var att se hur en applikations datatrafik påverkas av att klassiska intervallanrop ersätts av avvaktande AJAX-anrop. Detta görs genom att implementera respektive anropsmetod i två identiska alfapetapplikationer. Mätdata erhölls genom att låta användare spela längre omgångar av respektive applikation, vilket även genererar realistiska uppdateringar. Resultaten visar att den klientgenererade bandbreddskonsumtionen minskas vid användning av avvaktande AJAX-anrop. Detta gör den, i kontrast med klassiska intervallanrop, till en möjlig avlastningsmetod.

  • 11.
    Arias Ramos, Ceferino
    University of Skövde, School of Technology and Society.
    Programming and Image Processing in a Compact Production Cell2012Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In recent years, control system in the automation industries has become more and more useful, covering a wide range of fields, for example, industrial instrumentation, control and monitoring systems. Vision systems are used nowadays to improve products quality control, saving costs, time, and obtaining a better accuracy than a human operator in the manufacturing process of companies. Combining a vision system with a suitable automated system allow companies to cover a wide range of products and rapid production. All these factors are considered in this project.

    The aim of this project is to upgrade the functionality of a Nokia-Cell, which was used in a quality control process for the back shells of Nokia cell phones. The project includes design, upgrade and implementation of a new system in order to make the cell work properly. The Nokia-Cell is composed of the following basic modules: vision and image recognition system, automation system devices (PC and PLC, robot), and other mechatronics devices. The new system will consist of a new camera, due to the poor connectivity and quality of the old camera. For the same reason, a new PC will replace two older ones for communication and vision recognition. The new system will also include a new PLC of Beckhoff to replace the aging one of Omron so as to facilitate the connections using the same language. In addition, IEC-61499 Function Blocks standard is adopted for programming the Nokia-Cell.

    It is expected that the results of this project will contribute to both research and education in the future. In addition, it would be correctly to apply the results to industries in vision-based quality control systems.

  • 12.
    Arrieta, Aitor
    University of Skövde, The Virtual Systems Research Centre. University of Skövde, School of Technology and Society.
    FB-Environment in Wise-Shop Floor: Algorithm parser and code generation2012Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    IEC (International Electrotechnical Commission) is the authority that publishes different standards in the  fields  of  electrical  and  electronics  engineering,  to  be  used  internationally.  In  the  area  of manufacturing, it has demanded a new standard to fulfil better solutions of dynamic requirements. The  IEC  61499  redacted  by  IEC  offers  interoperability,  portability,  configurability  and  distributed control applications for manufacturing processes. However, this standard is not a replacement of IEC 61131-3,  one  of  the  most  used  standards  in  industry;  instead,  it  is  a  complement  of  it.  The  basic software units of IEC 61499 are named Function Blocks (FBs), which can be described as blocks that encapsulate functionality. By combining FBs together, it is possible to solve complex problems.   The  objective  of  this  project  (in  close  cooperation  with  another  project)  is  to  develop  a  software environment in Java language. It follows the requirements of IEC 61499, and implement a Function Block  designer  and  a  runtime  execution  environment,  as  a  part  of  an  existing  Wise-ShopFloor framework. The scope of this project covers:     FB  algorithm  editor:  Each  FB  has  one  or  more  algorithms,  which  can  be  defined  in  the algorithm editor using IEC 61131-3 or Java.     FB serialization: Opening and saving the configuration of FBs in Java Class file is one of the tasks  of  this  project.  As  soon  as  the  configuration  is  saved,  the  Java  code  of  FB  can  be generated. Java code is generated because compiled Java allows execution of FB. Saving in Java  Class  file  permits  portability,  i.e.  the  saved  configuration  can  be  opened  in  any  JVM system, and vice versa.      Case study: A simulation of an assembly station using an ABB IRB 140 robot is studied and implemented using the runtime simulator of the Java platform, in which some basic FBs have been also created in a library. This project also includes: (1) implementation of user interface and (2) FB serialization in XML. It  is  anticipated  that  the  developed  environment  will  be  able  to  save  and  open  FBs  configurations either in XML or in Java Class, following the specification of IEC 61499. It will allow portability and reusability.  Because  of  the  portability,  the  so-designed  FBs  can  be  validated  using  another  FB environment such as FBDK (Function Block Development Kit).

  • 13.
    Atif, Yacine
    et al.
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Ding, Jianguo
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Lindström, Birgitta
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Jeusfeld, Manfred
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Andler, Sten F.
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Yuning, Jiang
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Brax, Christoffer
    CombiTech AB, Skövde, Sweden.
    Gustavsson, Per M.
    CombiTech AB, Skövde, Sweden.
    Cyber-Threat Intelligence Architecture for Smart-Grid Critical Infrastructures Protection2017Conference paper (Refereed)
    Abstract [en]

    Critical infrastructures (CIs) are becoming increasingly sophisticated with embedded cyber-physical systems (CPSs) that provide managerial automation and autonomic controls. Yet these advances expose CI components to new cyber-threats, leading to a chain of dysfunctionalities with catastrophic socio-economical implications. We propose a comprehensive architectural model to support the development of incident management tools that provide situation-awareness and cyber-threats intelligence for CI protection, with a special focus on smart-grid CI. The goal is to unleash forensic data from CPS-based CIs to perform some predictive analytics. In doing so, we use some AI (Artificial Intelligence) paradigms for both data collection, threat detection, and cascade-effects prediction. 

  • 14.
    Axelsson, Jonathan
    et al.
    University of Skövde, School of Engineering Science.
    Hultberg, Carl
    University of Skövde, School of Engineering Science.
    Realtidsstyrning av robotiserad kameraplattform2018Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Swedish Defence Material Administration (FMV) that supplies materials to the Swedish military, has a part of its organization located in Karlsborg called test and evaluation of land combat systems. The photogroup of test and evaluation wishes to control a robotized camera platform, of the brand Vinten, in real time using a number of different positioning systems like joystick, Doppler-position radar, their self-constructed system UNIPOS and using a predicted trajectory of a launched projectile. The main goal of the project is therefore to create a control system to maneuver the camera platform with the assistance of mentioned data sources. The theoretical framework and literature review gave the members of the project the knowledge base, in serial communication and data protocols, needed to complete the project and gave understanding about earlier similar projects and choose to follow the structure of the systems development model Rational Unified Process (RUP). FMV wanted the main control unit to be a PC to be able to remotely control the system and to be able to make further developments. RUP was used to give the work structure and to make sure the quality of the end product was satisfactory. The development process consists, in accordance with the RUP structure, of a number of iterations that all add some function to the system. In close cooperation with the staff at FMV the system is developed and continuously tested to ensure the quality. A simple manual has been developed to make usage of the system easier. Every data source wanted by FMV has been handled in some way throughout the project and the result was a portable system that can be ran on any PC. Tests using drones, grenade launchers and a response-test was performed to verify that the functions of the system lives up to the goals that were set up and to evaluate the systems possibilities and limitations. The tests showed that real time control is possible to some extent with all systems and that the limitations lies in the delays that exists both in signal transfers and in the camera platforms built in filters for soft movements.

  • 15.
    Ayani, Mikel
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Ganebäck, Maria
    Projektengagemang Industri & Energi Sverige AB, El & Automation, Skövde, Sweden.
    Ng, Amos H. C.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Digital Twin: Applying emulation for machine reconditioning2018In: Procedia CIRP, ISSN 2212-8271, E-ISSN 2212-8271, Vol. 72, p. 243-248Article in journal (Refereed)
    Abstract [en]

    Old machine reconditioning projects extend the life length of machines with reduced investments, however they frequently involve complex challenges. Due to the lack of technical documentation and the fact that the machines are running in production, they can require a reverse engineering phase and extremely short commissioning times. Recently, emulation software has become a key tool to create Digital Twins and carry out virtual commissioning of new manufacturing systems, reducing the commissioning time and increasing its final quality. This paper presents an industrial application study in which an emulation model is used to support a reconditioning project and where the benefits gained in the working process are highlighted.

  • 16.
    Ayani, Mikel
    et al.
    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.
    Birtic, Martin
    University of Skövde, School of Engineering Science.
    Optimizing Cycle Time and Energy Efficiency of a Robotic Cell Using an Emulation Model2018In: Advances in Manufacturing Technology XXXII: Proceedings of the 16th International Conference on Manufacturing Research, incorporating the 33rd National Conference on Manufacturing Research, September 11–13, 2018, University of Skövde, Sweden / [ed] Peter Thorvald, Keith Case, Amsterdam: IOS Press, 2018, Vol. 8, p. 411-416Conference paper (Refereed)
    Abstract [en]

    Industrial automated systems are mostly designed and pre-adjusted to always work at their maximum production rate. This leaves room for important energy consumption reductions considering the production rate variations of factories in reality. This article presents a multi-objective optimization application targeting cycle time and energy consumption of a robotic cell. A novel approach is presented where an existing emulation model of a fictitious robotic cell was extended with low-level electrical components modeled and encapsulated as FMUs. The model, commanded by PLC and Robot Control software, was subjected to a multi-objective optimization algorithm in order to find the Pareto front between energy consumption and production rate. The result of the optimization process allows selecting the most efficient energy consumption for the robotic cell in order to achieve the required cycle.

  • 17.
    Backlund, Per
    et al.
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Engström, Henrik
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Johannesson, Mikael
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Lebram, Mikael
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Andersson Hagiwara, Magnus
    University of Borås, Sweden.
    Maurin Söderholm, Hanna
    University of Borås, Sweden.
    Enhancing Immersion with Contextualized Scenarios: Role-playing in prehospital care training2015In: VS-Games 2015: 7th International Conference on Games and Virtual Worlds for Serious Applications / [ed] Per Backlund, Henrik Engström & Fotis Liarokapis, IEEE Computer Society, 2015, p. 167-170Conference paper (Refereed)
  • 18.
    Bandaru, Sunith
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Deb, Kalyanmoy
    Michigan State University, USA.
    Temporal Innovization: Evolution of Design Principles Using Multi-objective Optimization2015In: Proceedings of the 8th International Conference on Evolutionary Multi-Criterion Optimization (EMO 2015), Springer, 2015, Vol. 9018, p. 79-93Conference paper (Refereed)
    Abstract [en]

    Multi-objective optimization yields multiple solutions each of which is no better or worse than the others when the objectives are conflicting. These solutions lie on the Pareto-optimal front which is a lower-dimensional slice of the objective space. Together, the solutions may possess special properties that make them optimal over other feasible solutions. Innovization is the process of extracting such special properties (or design principles) from a trade-off dataset in the form of mathematical relationships between the variables and objective functions. In this paper, we deal with a closely related concept called temporal innovization. While innovization concerns the design principles obtained from the trade-off front, temporal innovization refers to the evolution of these design principles during the optimization process. Our study indicates that not only do different design principles evolve at different rates, but that they start evolving at different times. We illustrate temporal innovization using several examples.

  • 19.
    Barrera Diaz, Carlos Alberto
    University of Skövde, School of Engineering Science. Volvo Cars Corporation Skövde.
    Discrete event simulation data management2016Independent thesis Advanced level (degree of Master (One Year)), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Simulation is one of the most important decision support tools that has been present during decades in the manufacturing industry. Discrete Event Simulation (DES) experiments analysis is an important engineering activity for efficient production. In order to improve this efficiency, many companies must develop a supporting framework, between engineers and the process information. Within DES it is also important the model provenance information because it validates the credibility of the model to be reused. Therefore, nowadays there is a great interest in the simulation community based on the reusability of the simulation models. The engineers at Volvo Cars Corporation (VCC) who work with DES technology, request and deliver a high number of Key Performance Indicators (KPIs). As a consequence it is difficult to present the simulation results in a standardized way. This thesis has investigated a way to reduce and standardize this time consuming process. Thus, by the study of what information and data must be documented and how it must be presented, the main goal of this thesis was to improve the efficiency of a company, when a DES project is being developed. A survey based on VCC simulation projects, was undertaken with the aim to find the output data and the information that must be included in a standardized report. First, the information of the projects was categorized in three main groups: general information, input data and output data. Within these groups, the provenance metadata which allows the reuse of the DES project, was identified. Then, after the analysis of 23 reports from DES projects, most frequent scenarios and their related output data were identified. All the findings were used for the implementation of a standardized and automated data-handling system which simplify the project documentation task to the engineers. This data-handling system exports the key output data from the simulation software to the report designed. Validation interviews show a strong acceptance among the engineers at VCC. Finally, in order to properly keep in track with all the provenance information when a DES project is being performed, a management method was proposed as well.

  • 20.
    Barrera Diaz, Carlos Alberto
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Oscarsson, Jan
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Lidberg, Simon
    Volvo Car Corporation, Skövde, Sweden.
    Sellgren, Tommy
    Volvo Car Corporation, Skövde, Sweden.
    A Study of Discrete Event Simulation Project Data and Provenance Information Management in an Automotive Manufacturing Plant2017In: Proceedings of the 2017 Winter Simulation Conference / [ed] W. K. V. Chan, A. D’Ambrogio, G. Zacharewicz, N. Mustafee, G. Wainer, E. Page, IEEE, 2017, , p. 12p. 4012-4023Conference paper (Refereed)
    Abstract [en]

    Discrete Event Simulation (DES) project data management is a complex and important engineering activity which impacts on an organization’s efficiency. This efficiency could be decreased by the lack of provenance information or the unreliability of existing information regarding previous simulation projects, all of which complicates the reusability of the existing data. This study presents an analysis of the management of simulation projects and their provenance data, according to the different types of scenarios usually found at a manufacturing plant. A survey based on simulation projects at an automotive manufacturing plant was conducted, in order to categorize the information regarding the studied projects, map the available provenance data and standardize its management. This study also introduces an approach that demonstrates how a structured framework based on the specific data involved in the different types of scenarios could allow an improvement of the management of DES projects.

  • 21.
    Barrera Diaz, Carlos Alberto
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Oscarsson, Jan
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Lidberg, Simon
    Manufacturing Engineering, Research and Simulation, Volvo Car Corporation, Skövde, Sweden.
    Sellgren, Tommy
    Manufacturing Engineering, Research and Simulation, Volvo Car Corporation, Skövde, Sweden.
    Discrete Event Simulation Output Data-Handling System in an Automotive Manufacturing Plant2018In: Procedia Manufacturing, E-ISSN 2351-9789, Vol. 25, p. 8p. 23-30Article in journal (Refereed)
    Abstract [en]

    Discrete Event Simulation is a comprehensive tool for the analysis and design of manufacturing systems. Over the years, considerable efforts to improve simulation processes have been made. One step in these efforts is the standardisation of the output data through the development of an appropriate system which presents the results in a standardised way. This paper presents the results of a survey based on simulation projects undertaken in the automotive industry. In addition, it presents the implementation of an automated output data-handling system which aims to simplify the project’s documentation task for the simulation engineers and make the results more accessible for other stakeholders.

  • 22.
    Bentabol Muñoz, Emilio
    et al.
    University of Skövde, School of Engineering Science.
    Bosque Ibáñez, Carlos
    University of Skövde, School of Engineering Science.
    González Ruiz, Pedro
    University of Skövde, School of Engineering Science.
    Hurtado de Mendoza, Jose Manuel
    University of Skövde, School of Engineering Science.
    Ruiz Zúñiga, Enrique
    University of Skövde, School of Engineering Science.
    Linking Wise-ShopFloor to an ABB IRB-140 Robot: Remote control, monitoring, and programming of an ABB robot IRC 5 through the internet2010Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    The aim of this project is integrate the new robot IRB140 from ABB inside the application Wise ShopFloor (Web-based integrated sensor-driven e-ShopFloor) and the integration of a web camera inside the application as well. In order to integrate the ABB IRB140 inside the application, a Java 3D model has to be created, the kinematics and collision constrains have to be defined also and the GUI application modified to fit the virtual model and the camera inside the application. The user has to be able to jog the web camera and zoom it. Changes in the server side have been done in order to introduce new functionalities such as the sessions management, the communication mechanism now is more general using Java inheritance.

  • 23.
    Berg Marklund, Björn
    et al.
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Backlund, Per
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Dahlin, Carl-Johan
    ius information AB, Skövde, Sweden.
    Engström, Henrik
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Wilhelmsson, Ulf
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    A Game-Based Approach to Support Social Presence and Awareness in Distributed Project-Based Learning2014In: International Journal of Games Based Learning, ISSN 2155-6849, E-ISSN 2155-6857, Vol. 4, no 1, p. 1-20Article in journal (Refereed)
    Abstract [en]

    An important factor for success in project-based learning (PBL) is that the involved project groups establish an atmosphere of social interaction in their working environment. In PBL-scenarios situated in distributed environments, most of a group's work-processes are mediated through the use of production-focused tools that are unconcerned with the important informal and social aspects of a project. On the other hand, there are plenty of tools and platforms that focus on doing the opposite and mainly support informal bonding (e.g., Facebook), but these types of environments can be obtrusive and contain distractions that can be detrimental to a group's productivity and are thus often excluded from working environments. The aim of this paper is to examine how a game-based multi-user environment (MUVE) can be designed to support project-based learning by bridging the gap between productivity-focused and social software. To explore this, the authors developed a game-based MUVE which was evaluated in a PBL-scenario. The result of the study revealed several crucial design elements that are needed to make such a MUVE work effectively, and that the acceptance towards game-based MUVEs is high, even with a rudimentary execution.

  • 24.
    Bergqvist, Emil
    University of Skövde, School of Informatics.
    Auditory displays: A study in effectiveness between binaural and stereo audio to support interface navigation2014Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis analyses if the change of auditory feedback can improve the effectiveness of performance in the interaction with a non-visual system, or with a system used by individuals with visual impairment. Two prototypes were developed, one with binaural audio and the other with stereo audio. The interaction was evaluated in an experiment where 22 participants, divided into two groups, performed a number of interaction tasks. A post-interview were conducted together with the experiment. The result of the experiment displayed that there were no great difference between binaural audio and stereo regarding the speed and accuracy of the interaction. The post-interviews displayed interesting differences in the way participants visualized the virtual environment that affected the interaction. This opened up interesting questions for future studies.

  • 25.
    Bergström, Erik
    et al.
    University of Skövde, The Informatics Research Centre. University of Skövde, School of Informatics.
    Pehrsson, Helen
    University of Skövde, The Informatics Research Centre. University of Skövde, School of Informatics.
    Performance Assessments in Computer Science - An example of student perceptions2014In: Next Generation Learning Conference: Conference Summary / [ed] Erik Brunnert Walfridsson, 2014, p. 4-16Conference paper (Refereed)
  • 26.
    Bermúdez Román, Abel
    et al.
    University of Skövde, School of Engineering Science.
    Gaztelumendi Arriaga, Javier
    University of Skövde, School of Engineering Science.
    Building and programming an autonomous robot using a Raspberry Pi as a PLC2016Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    PLC programming students are often limited to simulated systems or soft PLCs, because the high price of the hardware and the software licenses make it difficult for faculties to use real equipment for teaching. This paper describes the design and building of a PLC controlled self-balancing robot with CodeSys and Raspberry Pi as a low-cost demonstrator model that students can use as a base to interact with a real system. A first prototype has been developed, which can be used in the future to get students involved in beginner automation courses without having to build a system from scratch.

  • 27.
    Bi, Z. M.
    et al.
    Department of Engineering, Indiana University Purdue University Fort Wayne, Fort Wayne, IN, United States.
    Wang, Lihui
    University of Skövde, School of Technology and Society. University of Skövde, The Virtual Systems Research Centre.
    A Study on Optimal Machine Setups Using an Energy Modeling Approach2012In: Proceedings of NAMRI/SME, Society of Manufacturing Engineers, North American Manufacturing Research Institution of SME , 2012, p. 571-579Conference paper (Refereed)
    Abstract [en]

    In this paper, energy models are developed based on the kinematic and dynamic behaviors of chosen machine tools. One significant benefit of the developed energy models is their inherited relationship to the design variables involved in the manufacturing processes. Therefore, they can be readily applied to optimize process parameters to reduce energy consumption. A new parallel kinematic machine Exechon is used as a case study to demonstrate the procedures of energy model development with direct relation to appropriate process parameters. The derived energy model is then used for simulation of drilling operations on aircraft components to demonstrate its feasibility. Simulation results indicate that the developed energy model has led to an optimized machine setup which only consumes less than one-third of the energy of an average machine setup over the workspace. This approach can be extended and applied to other machines to establish their energy models for green manufacturing.

  • 28.
    Bi, Z. M.
    et al.
    Indiana University Purdue University Fort Wayne.
    Wang, Lihui
    University of Skövde, The Virtual Systems Research Centre. University of Skövde, School of Technology and Society.
    Energy Modeling of Machine Tools for Optimization of Machine Setups2012In: IEEE Transactions on Automation Science and Engineering, ISSN 1545-5955, E-ISSN 1558-3783, Vol. 9, no 3, p. 607-613Article in journal (Refereed)
    Abstract [en]

    In this paper, a new energy model is developed based on the kinematic and dynamic behaviors of a chosen machine tool. One significant benefit of the developed energy model is their inherited relationship to the design variables involved in the manufacturing processes. Without radical changes of the machine tool’s structure, the proposed model can be readily applied to optimize process parameters to reduce energy consumption. A new parallel kinematic machine Exechon is used as a case study to demonstrate the modeling procedure. The derived energy model is then used for simulation of drilling operations on aircraft components to verify its feasibility. Simulation results indicate that the developed energy model has led to an optimized machine setup which only consumes less than one-third of the energy of an average machine setup over the workspace. This approach can be extended and applied to other machines to establish their energy models for green and sustainable manufacturing.

  • 29.
    Bi, Z.M.
    et al.
    Indiana University Purdue University Fort Wayne.
    Wang, Lihui
    University of Skövde, The Virtual Systems Research Centre. University of Skövde, School of Technology and Society.
    Dynamic control model of a cobot with three omni-wheels2010In: Robotics and Computer-Integrated Manufacturing, ISSN 0736-5845, E-ISSN 1879-2537, Vol. 26, no 6, p. 558-563Article in journal (Refereed)
    Abstract [en]

    In this paper, a new collaborative robot with omni-wheels has been proposed and its dynamic control has been developed and validated. Collaborative robots (Cobots) have been introduced to guide and assist human operators to move heavy objects in a given trajectory. Most of the existing cobots use steering wheels; typical drawbacks of using steering wheels include the difficulties to (i) follow a trajectory with a curvature larger than that of the base platform, (ii) mount encoders on steering wheels due to self-spinning of the wheels, and (iii) quarantine dynamic control performance since it is purely kinematic  control.  The  new  collaborative  robot  is  proposed  to  overcome  the  above-mentioned shortcomings. The methodologies for its dynamic control are focused and the simulation has been conducted to validate the control performance of the system.

  • 30.
    Billing, Erik
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    A New Look at Habits using Simulation Theory2017In: Proceedings of the Digitalisation for a Sustainable Society: Embodied, Embedded, Networked, Empowered through Information, Computation & Cognition, Göteborg, Sweden, 2017Conference paper (Refereed)
    Abstract [en]

    Habits as a form of behavior re-execution without explicit deliberation is discussed in terms of implicit anticipation, to be contrasted with explicit anticipation and mental simulation. Two hypotheses, addressing how habits and mental simulation may be implemented in the brain and to what degree they represent two modes brain function, are formulated. Arguments for and against the two hypotheses are discussed shortly, specifically addressing whether habits and mental simulation represent two distinct functions, or to what degree there may be intermediate forms of habit execution involving partial deliberation. A potential role of habits in memory consolidation is also hypnotized.

  • 31.
    Billing, Erik
    et al.
    Umeå universitet, Institutionen för datavetenskap.
    Hellström, Thomas
    Umeå universitet, Institutionen för datavetenskap.
    Janlert, Lars Erik
    Umeå universitet, Institutionen för datavetenskap.
    Predictive learning from demonstration2011In: Agents and Artificial Intelligence: Second International Conference, ICAART 2010, Valencia, Spain, January 22-24, 2010. Revised Selected Papers / [ed] Filipe, Joaquim; Fred, Ana; Sharp, Bernadette, Berlin: Springer Verlag , 2011, 1, p. 186-200Chapter in book (Refereed)
    Abstract [en]

    A model-free learning algorithm called Predictive Sequence Learning (PSL) is presented and evaluated in a robot Learning from Demonstration (LFD) setting. PSL is inspired by several functional models of the brain. It constructs sequences of predictable sensory-motor patterns, without relying on predefined higher-level concepts. The algorithm is demonstrated on a Khepera II robot in four different tasks. During training, PSL generates a hypothesis library from demonstrated data. The library is then used to control the robot by continually predicting the next action, based on the sequence of passed sensor and motor events. In this way, the robot reproduces the demonstrated behavior. PSL is able to successfully learn and repeat three elementary tasks, but is unable to repeat a fourth, composed behavior. The results indicate that PSL is suitable for learning problems up to a certain complexity, while higher level coordination is required for learning more complex behaviors.

  • 32.
    Billing, Erik
    et al.
    Umeå universitet, Institutionen för datavetenskap.
    Hellström, Thomas
    Umeå universitet, Institutionen för datavetenskap.
    Janlert, Lars Erik
    Umeå universitet, Institutionen för datavetenskap.
    Simultaneous control and recognition of demonstrated behavior2011Report (Other academic)
    Abstract [en]

    A method for Learning from Demonstration (LFD) is presented and evaluated on a simulated Robosoft Kompai robot. The presented algorithm, called Predictive Sequence Learning (PSL), builds fuzzy rules describing temporal relations between sensory-motor events recorded while a human operator is tele-operating the robot. The generated rule base can be used to control the robot and to predict expected sensor events in response to executed actions. The rule base can be trained under different contexts, represented as fuzzy sets. In the present work, contexts are used to represent different behaviors. Several behaviors can in this way be stored in the same rule base and partly share information. The context that best matches present circumstances can be identified using the predictive model and the robot can in this way automatically identify the most suitable behavior for precent circumstances. The performance of PSL as a method for LFD is evaluated with, and without, contextual information. The results indicate that PSL without contexts can learn and reproduce simple behaviors. The system also successfully identifies the most suitable context in almost all test cases. The robot's ability to reproduce more complex behaviors, with partly overlapping and conflicting information, significantly increases with the use of contexts. The results support a further development of PSL as a component of a dynamic hierarchical system performing control and predictions on several levels of abstraction. 

  • 33.
    Billing, Erik
    et al.
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Hellström, Thomas
    Institutionen för Datavetenskap, Umeå Universitet.
    Janlert, Lars-Erik
    Institutionen för Datavetenskap, Umeå Universitet.
    Simultaneous recognition and reproduction of demonstrated behavior2015In: Biologically Inspired Cognitive Architectures, ISSN 2212-683X, Vol. 12, p. 43-53, article id BICA114Article in journal (Refereed)
    Abstract [en]

    Predictions of sensory-motor interactions with the world is often referred to as a key component in cognition. We here demonstrate that prediction of sensory-motor events, i.e., relationships between percepts and actions, is sufficient to learn navigation skills for a robot navigating in an apartment environment. In the evaluated application, the simulated Robosoft Kompai robot learns from human demonstrations. The system builds fuzzy rules describing temporal relations between sensory-motor events recorded while a human operator is tele-operating the robot. With this architecture, referred to as Predictive Sequence Learning (PSL), learned associations can be used to control the robot and to predict expected sensor events in response to executed actions. The predictive component of PSL is used in two ways: 1) to identify which behavior that best matches current context and 2) to decide when to learn, i.e., update the confidence of different sensory-motor associations. Using this approach, knowledge interference due to over-fitting of an increasingly complex world model can be avoided. The system can also automatically estimate the confidence in the currently executed behavior and decide when to switch to an alternate behavior. The performance of PSL as a method for learning from demonstration is evaluated with, and without, contextual information. The results indicate that PSL without contextual information can learn and reproduce simple behaviors, but fails when the behavioral repertoire becomes more diverse. When a contextual layer is added, PSL successfully identifies the most suitable behavior in almost all test cases. The robot's ability to reproduce more complex behaviors, with partly overlapping and conflicting information, significantly increases with the use of contextual information. The results support a further development of PSL as a component of a dynamic hierarchical system performing control and predictions on several levels of abstraction. 

  • 34.
    Billing, Erik
    et al.
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Lowe, Robert
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre. Department of Applied IT, University of Gothenburg, Sweden.
    Sandamirskaya, Yulia
    Institute of Neuroinformatics, University of Zurich and ETH Zurich, Switzerland.
    Simultaneous Planning and Action: Neural-dynamic Sequencing of Elementary Behaviors in Robot Navigation2015In: Adaptive Behavior, ISSN 1059-7123, E-ISSN 1741-2633, Vol. 23, no 5, p. 243-264Article in journal (Refereed)
    Abstract [en]

    A technique for Simultaneous Planning and Action (SPA) based on Dynamic Field Theory (DFT) is presented. The model builds on previous workon representation of sequential behavior as attractors in dynamic neural fields. Here, we demonstrate how chains of competing attractors can be used to represent dynamic plans towards a goal state. The presentwork can be seen as an addition to a growing body of work that demonstratesthe role of DFT as a bridge between low-level reactive approachesand high-level symbol processing mechanisms. The architecture is evaluatedon a set of planning problems using a simulated e-puck robot, including analysis of the system's behavior in response to noise and temporary blockages ofthe planned route. The system makes no explicit distinction betweenplanning and execution phases, allowing continuous adaptation of the planned path. The proposed architecture exploits the DFT property of stability in relation to noise and changes in the environment. The neural dynamics are also exploited such that stay-or-switch action selection emerges where blockage of a planned path occurs: stay until the transient blockage is removed versus switch to an alternative route to the goal.

  • 35.
    Birtic, Martin
    University of Skövde, School of Engineering Science.
    An Open Data Model for Emulation Models of Industrial Components2018Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Emulation is a technology, historically mostly used for virtual commissioning of automated industrial systems, and operator training. Trends show that new areas for deployment are being investigated. One way to broaden the scope of emulation technology is to increase emulation detail level. The University of Skövde conduct research within emulation technology, and are developing a higher detail level emulation platform performing  on component level. For transparent and systematic development of component models on this level, an open, extensible, and flexible data model for emulation models of industrial components is wanted. This thesis is contributing to this endeavour by developing a first draft of such a data model. A demonstration is also conducted by implementing a few components into the developing emulation environment, using XML as file format. An iterative "design and creation" methodology was used to develop and implement an object oriented data model. A selected set of industrial components were used to develop and demonstrate the data model, and the final result is visually represented as a class diagram together with explanatory documentation. Using the methodology and data modelling strategy used in this thesis, systematic and transparent development of emulation models on component level is possible in an extensible and flexible manner.

  • 36.
    Bjurén, Johan
    University of Skövde, School of Informatics.
    USING CASE-BASED REASONING FOR PREDICTING ENERGY USAGE2013Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    In this study, the inability to in a future meet the electricity demand and the urge to change the consumption behavior considered. In a smart grid context there are several possible ways to do this. Means include ways to increase the consumer’s awareness, add energy storages or build smarter homes which can control the appliances. To be able to implement these, indications on how the future consumption will be could be useful. Therefore we look further into how a framework for short-term consumption predictions can be created using electricity consumption data in relation to external factors. To do this a literature study is made to see what kind of methods that are relevant and which qualities is interesting to look at in order to choose a good prediction method. Case Based Reasoning seemed to be able to be suitable method. This method was examined further and built using relational databases. After this the method was tested and evaluated using datasets and evaluation methods CV, MBE and MAPE, which have previously been used in the domain of consumption prediction. The result was compared to the results of the winning methods in the ASHRAE competition. The CBR method was expected to perform better than what it did, and still not as good as the winning methods from the ASHRAE competition. The result showed that the CBR method can be used as a predictor and has potential to make good energy consumption predictions. and there is room for improvement in future studies.

  • 37.
    Boberg, Arvid
    University of Skövde, School of Engineering Science.
    HRC implementation in laboratory environment: Development of a HRC demonstrator2018Independent thesis Advanced level (degree of Master (One Year)), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Eurofins is one of the world's largest laboratories which, among other things, offer chemical and microbiological analyses in agriculture, food and environment. Several 100.000 tests of various foods are executed each year at Eurofins’ facility in Jönköping and the current processes include much repeated manual tasks which could cause ergonomic problems. The company therefore wants to investigate the possibilities of utilizing Human-Robot Collaboration (HRC) at their facility. Human-Robot Collaboration is a growing concept that has made a big impression in both robot development and Industry 4.0. A HRC approach allow humans and robots to share their workspaces and work side by side, without being separated by a protective fence which is common among traditional industrial robots. Human-Robot Collaboration is therefore believed to be able to optimize the workflows and relieve human workers from unergonomic tasks.

    The overall aim of the research project presented is to help the company to gain a better understanding about the existing HRC technologies. To achieve this goal, the state-of-the-art of HRC had to be investigated and the needs, possibilities and limitations of HRC applications had to be identified at Eurofins’ facility. Once these have been addressed, a demonstrator could be built which could be used for evaluating the applicability and suitability of HRC at Eurofins.

    The research project presented used the design science research process. The state-of-the-art of HRC was studied in a comprehensive literature review, reviewing sterile robots and mobile robotics as well. The presented literature review could identify possible research gaps in both HRC in laboratory environments and mobile solutions for HRC applications. These areas studied in the literature review formed together the basis of the prepared observations and interviews, used to generate the necessary data to develop the design science research artefact, the demonstrator.

    ABB's software for robotic simulation and offline programming, RobotStudio, were used in the development of the demonstrator, with the collaborative robot YuMi chosen for the HRC implementation. The demonstrator presented in the research project has been built, tested and refined in accordance to the design science research process. When the demonstrator could illustrate an applicable solution, it was evaluated for its performance and quality using a mixed methods approach.

    Limitations were identified in both the performance and quality of the demonstrator's illustrated HRC implementation, including adaptability and sterility constraints. The research project presented could conclude that a HRC application would be possible at a station which were of interest by the company, but would however not be recommended due to the identified constraints. Instead, the company were recommended to look for stations which are more standardized and have less hygienic requirements. By the end of the research project, additional knowledge was contributed to the company, including how HRC can affect today's working methods at Eurofins and in laboratory environments in general.

  • 38.
    Boberg, Arvid
    University of Skövde, School of Engineering Science.
    Virtual lead-through robot programming: Programming virtual robot by demonstration2015Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This report describes the development of an application which allows a user to program a robot in a virtual environment by the use of hand motions and gestures. The application is inspired by the use of robot lead-through programming which is an easy and hands-on approach for programming robots, but instead of performing it online which creates loss in productivity the strength from offline programming where the user operates in a virtual environment is used as well. Thus, this is a method which saves on the economy and prevents contamination of the environment. To convey hand gesture information into the application which will be implemented for RobotStudio, a Kinect sensor is used for entering the data into the virtual environment. Similar work has been performed before where, by using hand movements, a physical robot’s movement can be manipulated, but for virtual robots not so much. The results could simplify the process of programming robots and supports the work towards Human-Robot Collaboration as it allows people to interact and communicate with robots, a major focus of this work. The application was developed in the programming language C# and has two different functions that interact with each other, one for the Kinect and its tracking and the other for installing the application in RobotStudio and implementing the calculated data into the robot. The Kinect’s functionality is utilized through three simple hand gestures to jog and create targets for the robot: open, closed and “lasso”. A prototype of this application was completed which through motions allowed the user to teach a virtual robot desired tasks by moving it to different positions and saving them by doing hand gestures. The prototype could be applied to both one-armed robots as well as to a two-armed robot such as ABB’s YuMi. The robot's orientation while running was too complicated to be developed and implemented in time and became the application's main bottleneck, but remained as one of several other suggestions for further work in this project.

  • 39.
    Carlsson, Henric
    University of Skövde, School of Informatics.
    Using A Recommender To Influence Consumer Usage2013Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    In this dissertation, the issues of the increased awareness of energy use are considered. Energy technologies are continuously improved by energy retailers and academic researchers. The Smart Grid are soon customary as part of the energy domain. But in order to improve energy efficiency the change must come from the consumers. Consumers should be active decision makers in the Smart Grid domain and therefor a Recommender system suits the Smart Grid and enables customers. Customers will not use energy in the way energy retailers, and politicians advocates instead they will do what fits them. By investigating how a Recommender can be built in the Smart Grid we focus on parameters and information that supports the costumers and enables positive change. An investigation of what customers perceive as relevant is pursued as well as how relevancy can adjust the system. A conceptual model of how to build a Recommender is rendered through a literature review, a group interview and a questionnaire.

  • 40.
    Casas-Roma, Jordi
    et al.
    Faculty of Computer Science, Multimedia and Telecommunications, Internet Interdisciplinary Institute (IN3), Universitat Oberta de Catalunya, Barcelona, Spain.
    Herrera-Joancomartí, Jordi
    Department of Information and Communications Engineering, Universitat Autònoma de Barcelona, Bellaterra, Spain.
    Torra, Vicenç
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    A survey of graph-modification techniques for privacy-preserving on networks2017In: Artificial Intelligence Review, ISSN 0269-2821, E-ISSN 1573-7462, Vol. 47, no 3, p. 341-366Article in journal (Refereed)
    Abstract [en]

    Recently, a huge amount of social networks have been made publicly available. In parallel, several definitions and methods have been proposed to protect users’ privacy when publicly releasing these data. Some of them were picked out from relational dataset anonymization techniques, which are riper than network anonymization techniques. In this paper we summarize privacy-preserving techniques, focusing on graph-modification methods which alter graph’s structure and release the entire anonymous network. These methods allow researchers and third-parties to apply all graph-mining processes on anonymous data, from local to global knowledge extraction.

  • 41.
    Crowston, Kevin
    et al.
    Syracuse University, Syracuse, NY, USA.
    Hammouda, ImedUniversity of Gothenburg, Sweden.Lundell, BjörnUniversity of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.Robles, GregorioGSyC, Universidad Rey Juan Carlos, Madrid, Spain.Gamalielsson, JonasUniversity of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.Lindman, JuhoChalmers, Gothenburg, Sweden / University of Gothenburg, Gothenburg, Sweden.
    Open Source Systems: Integrating Communities: 12th IFIP WG 2.13 International Conference, OSS 2016, Gothenburg, Sweden, May 30 - June 2, 2016, Proceedings2016Conference proceedings (editor) (Refereed)
    Abstract [en]

    This book constitutes the refereed proceedings of the 12th International IFIP WG 2.13 International Conference on Open Source Systems, OSS 2016, held in Gothenburg, Sweden, in May/June 2016. The 13 revised full papers presented were carefully reviewed and selected from 38 submissions. The papers cover a wide range of topics related to free, libre, and open source software, including: organizational aspects of communities; organizational adoption; participation of women; software maintenance and evolution; open standards and open data; collaboration; hybrid communities; code reviews; and certification.

  • 42.
    Da Lio, Mauro
    et al.
    Dept. of Industrial Engineering University of Trento, Trento, Italy.
    Mazzalai, Alessandro
    Dept. of Industrial Engineering University of Trento, Trento, Italy.
    Windridge, David
    Dept. of Computer Science Middlesex University, London, United Kingdom.
    Thill, Serge
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre. Centre for Robotics and Neural Systems, University of Plymouth, United Kingdom.
    Svensson, Henrik
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Yueksel, Mehmed
    Robotics Innovation Center - DFKI GmbH German Research Center for Artificial Intelligence Bremen, Germany.
    Gurney, Kevin
    Dept. of Psychology University of Sheffield, Sheffield, United Kingdom.
    Saroldi, Andrea
    Centro Ricerche Fiat S.C.p.A. Orbassano (TO), Italy.
    Andreone, Luisa
    Centro Ricerche Fiat S.C.p.A. Orbassano (TO), Italy.
    Anderson, Sean R.
    Dept. of Automatic Control and Systems Engineering University of Sheffield, Sheffield, United Kingdom.
    Heich, Hermann-Josef
    Consulting – Research – Project Management Heich Consult GmbH, Hürth, Germany.
    Exploiting Dream-Like Simulation Mechanisms to Develop Safer Agents for Automated Driving The "Dreams4Cars" EU Research and Innovation Action2017In: 2017 IEEE 20th International Conference on Intelligent Transportation Systems (ITSC), IEEE, 2017Conference paper (Refereed)
    Abstract [en]

    Automated driving needs unprecedented levels of reliably and safety before marked deployment. The average human driver fatal accident rate is 1 every 100 million miles. Automated vehicles will have to provably best these figures. This paper introduces the notion of dream-like mechanisms as a simulation technology to produce a large number of hypothetical design and test scenarios - especially focusing on variations of more frequent dangerous and near miss events. Grounded in the simulation hypothesis of cognition, we show here some principles for effective simulation mechanisms and an artificial cognitive system architecture that can learn from the simulated situations.

  • 43.
    Dahlbom, Anders
    et al.
    University of Skövde, School of Humanities and Informatics. University of Skövde, The Informatics Research Centre.
    Nordlund, Per-Johan
    Aeronautics, Saab AB, Linköping, Sweden.
    Detection of Hostile Aircraft Behaviors using Dynamic Bayesian Networks2013In: Proceedings of the 16th International Conference on Information Fusion, IEEE Press, 2013, p. 2033-2040Conference paper (Refereed)
    Abstract [en]

    Aircraft Combat Survivability in military air operations is concerned with survival of the own aircraft. This entails analysis of information, detection and estimation of threats, and the implementation of actions to counteract detected threats. Beyond visual range weapons can today be fired from one hundred kilometers away, making them difficult to detect and track. One approach for providing early warnings of such threats is to analyze the kinematic behavior of enemy aircraft in order to detect situations that may point to malicious intent. In this paper we investigate the use of dynamic Bayesian networks for detecting hostile aircraft behaviors.

  • 44.
    Danielsson, Oscar
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Syberfeldt, Anna
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Brewster, Rodney
    Volvo Car Corporation, Skövde, Sweden.
    Wang, Lihui
    KTH Royal Institute of Technology, Kungliga Tekniska högskolan, Stockholm.
    Assessing Instructions in Augmented Reality for Human-Robot Collaborative Assembly by Using Demonstrators2017In: Manufacturing Systems 4.0 - Proceedings of the 50th CIRP Conference on Manufacturing Systems / [ed] Mitchell M. Tseng, Hung-Yin Tsai, Yue Wang, Elsevier, 2017, Vol. 63, p. 89-94Conference paper (Refereed)
    Abstract [en]

    Robots are becoming more adaptive and aware of their surroundings. This has opened up the research area of tight human-robot collaboration,where humans and robots work directly interconnected rather than in separate cells. The manufacturing industry is in constant need ofdeveloping new products. This means that operators are in constant need of learning new ways of manufacturing. If instructions to operatorsand interaction between operators and robots can be virtualized this has the potential of being more modifiable and available to the operators.Augmented Reality has previously shown to be effective in giving operators instructions in assembly, but there are still knowledge gapsregarding evaluation and general design guidelines. This paper has two aims. Firstly it aims to assess if demonstrators can be used to simulatehuman-robot collaboration. Secondly it aims to assess if Augmented Reality-based interfaces can be used to guide test-persons through apreviously unknown assembly procedure. The long-term goal of the demonstrator is to function as a test-module for how to efficiently instructoperators collaborating with a robot. Pilot-tests have shown that Augmented Reality instructions can give enough information for untrainedworkers to perform simple assembly-tasks where parts of the steps are done with direct collaboration with a robot. Misunderstandings of theinstructions from the test-persons led to multiple errors during assembly so future research is needed in how to efficiently design instructions.

  • 45.
    Danielsson, Oscar
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Syberfeldt, Anna
    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.
    Wang, Lihui
    KTH Royal Institue of Technology, Stockholm, Sweden.
    Operators perspective on augmented reality as a support tool in engine assembly2018In: Procedia CIRP, ISSN 2212-8271, E-ISSN 2212-8271, Vol. 72, p. 45-50Article in journal (Refereed)
    Abstract [en]

    Augmented Reality (AR) has shown its potential in supporting operators in manufacturing. AR-glasses as a platform both in industrial use are emerging markets, thereby making portable and hands-free AR more and more feasible. An important aspect of integrating AR as a support tool for operators is their acceptance of the technology. This paper presents the results of interviewing operators regarding their view on AR technology in their field and observing them working in automotive engine assembly and how they interact with current instructions. The observations and follow-up questions identified three main aspects of the information that the operators looked at: validating screw torque, their current assembly time, and if something went wrong. The interviews showed that a large amount of the operators were positive towards using AR in assembly. This has given an insight in both the current information interaction the operators do and their view on the potential in using AR. Based on these insights we suggest a mock-up design of an AR-interface for engine assembly to serve as a base for future prototype designs.

  • 46.
    De Vin, Leo J.
    University of Skövde, The Virtual Systems Research Centre. University of Skövde, School of Technology and Society.
    Credibility of Simulation Results - A Philosophical Perspective on Virtual Manufacturing2012In: The 13th Mechatronics Forum International Conference Proceedings: Vol. 3/3 / [ed] Rudolf Scheidl & Bernhard Jakoby, Linz: TRAUNER Verlag, 2012, p. 784-791Conference paper (Refereed)
    Abstract [en]

    This paper describes the factors that play a role in credibility of simulation results. It focuses on virtual manufacturing and in particular resource simulation as an example. However, a simulation model can be used in a number of different ways. Verification and validation of models is amongst other factors important for credibility. In this area, much work has been carried out in defense research. There are also some striking similarities between virtual manufacturing and information fusion, in particular in the field of human competence development related to credibility of simulations.

  • 47.
    Deb, Kalyanmoy
    et al.
    Department of Electrical and Computer Engineering, Michigan State University, USA.
    Siegmund, Florian
    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.
    R-HV: A Metric for Computing Hyper-volume for Reference Point-based EMOs2015In: Swarm, Evolutionary, and Memetic Computing: 5th International Conference, SEMCCO 2014, Bhubaneswar, India, December 18-20, 2014, Revised Selected Papers / [ed] Bijaya Ketan Panigrahi, Ponnuthurai Nagaratnam Suganthan & Swagatam Das, Springer, 2015, p. 98-110Chapter in book (Refereed)
    Abstract [en]

    For evaluating performance of a multi-objective optimizationfor finding the entire efficient front, a number of metrics, such as hypervolume, inverse generational distance, etc. exists. However, for evaluatingan EMO algorithm for finding a subset of the efficient frontier, the existing metrics are inadequate. There does not exist many performancemetrics for evaluating a partial preferred efficient set. In this paper, wesuggest a metric which can be used for such purposes for both attainableand unattainable reference points. Results on a number of two-objectiveproblems reveal its working principle and its importance in assessingdifferent algorithms. The results are promising and encouraging for itsfurther use.

  • 48.
    Derenius, Fredrik
    University of Skövde, School of Humanities and Informatics.
    Framställandet av en säker LiveCD för distansarbetare: Ett projekt baserat på öppen källkod2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Studien ämnar undersöka hur en LiveCD kan stödja en säkrare datormiljö för distansarbetarepå ett enkelt sätt. Distansarbetare arbetar utanför arbetsplatsens säkrare datormiljö vilket gördem till en mer utsatt grupp av datoranvändare. Många av dagens datoranvändare tyckerdessutom säkerhet relaterat till datorer och nätverk är komplicerat. Implementerad lösningtillhandahåller därför möjligheten att med hjälp av en LiveCD och ett USB-minne få tillgångtill både en säker fjärranslutning och fjärrskrivbord, genom att enbart skriva in ett lösenord.Tjänsterna konfigureras alltså automatiskt i bakgrunden; användaren behöver inte hålla redapå mer än ett lösenord. En LiveCD är också ett skrivskyddat medium vilket innebär attskadlig kod har svårt att få fäste i systemet. Resultatet är att distansarbetare med olika behovoch kunskapsnivå gällande dator- och nätverksäkerhet erbjuds möjligheten till en säkraredatormiljö på ett enkelt sätt.

  • 49.
    Diaz Rios, Raul
    University of Skövde, School of Technology and Society.
    DEVELOPMENT OF A MANUFACTURING CELL IN COMPLIANCE WITH IEC 61499: Function Blocks networks implementation in a Gantry Robot system2012Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Standards are, nowadays, a useful and sometimes essential tool, in the world of automated industry. Since the development of the standard IEC 61131-3, automation has made progresses in a consistent manner. This allows an engineer to develop control programs for any type of systems using the language set in the standard. However, this standard was not enough because it did not cover the control over distributed systems. Therefore, it was necessary to establish rules in this field. In order to fill this gap, the new standard IEC 61499 was developed. Its main objective is to describe how to develop, design and implement distributed control systems, using the new concept of function blocks. By the use of the new function blocks, it is possible to control distributed systems in a quick and easy way, adding some advantages such as reusability, portability, and much enhanced maintenance.This project involves the preparation of a manufacturing cell composed of a gantry robot interacting with a CNC machine. The project is developed in two sections; one is focused on the computer programming with function blocks for the gantry robot and HMI, and the other is prepared for the programming of function blocks for the CNC machine and HMI. The communications between PLC, PC, gantry robot and CNC machine are developed using the standard IEC 61499. This document covers the survey and research made for the first section of the project.The new standard IEC 61499 provides the methodologies and the appropriated tools to achieve a good control in distributed systems. The basic tools offered by this standard are the new function blocks which will be the main tool used in this project. Equally important, it is necessary to take into account the different assembly features and the machining features in order to design better function blocks to control the system. An HMI has to be developed in order to obtain a good interface for a worker of this cell.The aim of this project is to investigate how the new standard IEC 61499 works in a real manufacturing cell and how the new function blocks interact in a real distributed system. Moreover, it is important to see how the event flow works, controlling all the sequences required in the manufacturing cell.

  • 50.
    Egaña Iztueta, Lander
    et al.
    University of Skövde, School of Engineering Science.
    Roda Martínez, Javier
    University of Skövde, School of Engineering Science.
    Function Block Algorithms for Adaptive Robotic Control2014Independent thesis Basic level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of this project is the creation of an adaptive Function Block control system, and the implementation of Artificial Intelligence integrated within the Function Block control system, using IEC 61499 standard to control an ABB 6-axis virtual robot, simulated in the software RobotStudio. To develop these objectives, we studied a lot of necessary concepts and how to use three different softwares. To learn how to use the softwares, some tests were carried out. RobotStudio is a program developed by ABB Robotics Company where an ABB robot and a station are simulated. There, we designed and created a virtual assembly cell with the virtual IRB140 robot and the necessary pieces to simulate the system. To control the robot and the direct access to the different tools of RobotStudio, it is necessary to use an application programming interface (API) developed by ABB Robotics Company. C sharp (C#) language is used to program using the API, but this language is not supported by the Function Block programming software nxtStudio. Because of this, we used VisualStudio software. In this software, we use the API libraries to start and stop the robot and load a RAPID file in the controller. In a RAPID file the instructions that the robot must follow are written. So, we had to learn about how to program in C# language and how to use VisualStudio software. Also, to learn about IEC 61499 standard it was necessary to read some books. This standard determines how an application should be programmed through function blocks. A function block is a unit of program with a certain functionality which contains data and variables that can be manipulated in the same function block by several algorithms. To program in this standard we learnt how to use nxtStudio software, consuming a lot of time because the program is quite complex and it is not much used in the industrial world yet. Some tests were performed to learn different programing skills in this standard, such as how to use UDP communication protocol and how to program interfaces. Learning UDP communication was really useful because it is necessary for communication between nxtStudio and other programs, and also learning how to use interfaces to let the user access the program. Once we had learnt about how to use and program the different softwares and languages, we began to program the project. Then, we had some troubles with nxtStudio because strings longer than fourteen characters cannot be used here. So, a motion alarm was developed in VisualStudio program. And another important limitation of nxtStudio is that C++ language cannot be used. Therefore, the creation of an Artificial Intelligence system was not possible. So, we created a Function Block control system. This system is a logistical system realised through loops, conditions and counters. All this makes the robot more adaptive. As the AI could not be carried out because of the different limitations, we theoretically designed the AI system. It will be possible to implement the AI when the limitations and the problems are solved.

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