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  • 1.
    Amir, Saman
    et al.
    Department of Marketing & Strategy and Center for Sustainability ResearchStockholm School of Economics, Stockholm Sweden.
    Abdullah Asif, Farazee Mohammad
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Roci, Malvina
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems. Department of Marketing & Strategy and Center for Sustainability ResearchStockholm School of EconomicsStockholmSweden.
    Towards Circular Economy: Enhanced Decision-Making in Circular Manufacturing Systems2021In: Sustainable Consumption and Production, Volume II: Circular Economy and Beyond / [ed] Ranjula Bali Swain, Susanne Sweet, Palgrave Macmillan, 2021, 1, p. 257-279Chapter in book (Refereed)
    Abstract [en]

    This chapter will present an outlook on the modelling and simulation of circular manufacturing systems. Simulations in the linear context have long been an enabler in making the systems efficient through better design and improved decision-making. Circular aspects of manufacturing systems lead to another level of complexity to be tackled and understood in terms of the performance of the system from an economic, environmental and social perspective. This calls for enhanced understanding through analysis of the interdependencies between business models, product design, supply chains and consumption patterns interactions by modelling the effect of those interactions to provide a sound basis for decision-making. The role of modelling simulation for prediction and improved decision-making in complex situations will be presented and exemplified with case studies where simulation has been used as a tool to enhance decision-making. The chapter finishes by highlighting the potential of modelling and simulation in boosting the transition towards circular systems implementation.

  • 2.
    Amir, Saman
    et al.
    Stockholm School of Economics.
    Salehi, Niloufar
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Roci, Malvina
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Sweet, Susanne
    Stockholm School of Economics.
    Rashid, Amir
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Towards circular economy: A guiding framework for circular supply chain implementation2022In: Business Strategy and the Environment, ISSN 0964-4733, E-ISSN 1099-0836Article in journal (Refereed)
    Abstract [en]

    Closing the loop for resource efficiency is a well-known practice in the industry. Toconcretize the circular economy implementation strategies, closed-loop thinkingrequires innovation and adaptation. Circular supply chains (CSCs) are one of the keyenablers in closing the loop by design or intention for value recovery and profit maxi-mization. CSC is an emerging area, and the view of CSC where forward and reversesupply chain is seamlessly integrated with the overall aim to achieve system-wide cir-cularity is missing in the academic debate. By offering a cross-functional perspectiveof CSC, this paper presents a CSC guiding framework to structure and understandthe underlying complexities and highlight the crucial elements of the CSC implemen-tation. Thus, this framework lays the basis for CSC within the systemic implementa-tion of CE by closing the loop by design or intention. The framework categorizes theCSC into four building blocks, namely, systemic approach, main drivers, levels of deci-sion making, and mechanisms to manage the full loop closure and minimize the inher-ent uncertainties of a complex system. The building blocks of the framework aresynthesized from various streams of supply chain literature and recurring concepts inthe circular economy literature. The CSC framework applicability is illustrated usingtwo industrial cases that are transitioning towards the circular economy.

  • 3.
    Archenti, Andreas
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Sustainable production development, Processledning och hållbar produktion.
    Laspas, Theodoros
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Accuracy and Performance Analysis of Machine Tools2019In: Metrology / [ed] Wei Gao, Singapore: Springer, 2019Chapter in book (Refereed)
    Abstract [en]

    The key to solve manufacturing quality and productivity problems in the machining of parts is to understand the physical attributes’ geometric/kinematic, static, dynamic, and thermal behavior of machine tools. In this chapter basic definitions, error sources, and instruments and methodologies for the identification and evaluation of machine tools’ physical attributes will be outlined.

    The first section presents the background and answers “why” it is important to measure and evaluate machine tools under no-load and loaded condition. Basic concepts and definitions of metrological terms will be given. In the second part, error sources in machine tools are introduced, and in the third part, instruments and methodologies for the accuracy evaluation of machine tools will be given.

  • 4.
    Archenti, Andreas
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Pettersson, Bo
    Hexagon.
    Method and test assembly for determining machine parameters2016Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    The invention pertains to a method for determining machine parameters of a mechanical device in which a first element and a second element are mutually movable in settable patterns of movement, the method comprising placing a measuring arm between the first and second elements, displacing the first and second elements mutually in a predetermined intended movement path, applying a predetermined force between the first element and the second element substantially in the longitudinal direction of the measuring arm, recording the resulting actual movement path by means of the measuring arm, thereby determining a difference between the intended movement path and the actual movement path, and deriving, based on the determined difference, machine parameters indicating a condition of the mechanical device, characterized in that the predetermined force comprises a dynamically varying portion. The invention furthermore pertains to a test assembly for performing said method.

  • 5.
    Dadbakhsh, Sasan
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Mertens, Raya
    Vanmeensel, Kim
    Ji, Gang
    Kruth, Jean-Pierre
    In situ transformations during SLM of an ultra-strong TiC reinforced Ti composite2020In: Scientific Reports, E-ISSN 2045-2322, Vol. 10, no 1, article id 10523Article in journal (Refereed)
    Abstract [en]

    This work demonstrates a successful in situ method capable of producing an ultra-strong novel Ti composite without aluminium and vanadium. In this method, selective laser melting is used to conduct in situ alloying and reinforcing of a Ti/10.5 wt% Mo2C powder mixture. It is shown that this leads to a metastable β-Ti matrix homogeneously reinforced by high aspect ratio, 50–200 nm wide and up to several micrometre long TiC whiskers. The transformations of the phases are controlled by decomposition, dissolution, diffusion, and reformation of constituents. The whisker morphology of in situ formed TiC particles is associated with directional crystal growth along the TiC<110> direction. The developed TiC reinforced β-Ti alloy combines a hardness over 500 HV, a Young’s modulus of 126 GPa, and an ultimate compressive strength of 1642 MPa. Improving the ductility of this composite is the subject of another work.

  • 6.
    Dadbakhsh, Sasan
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Zhao, Xiaoyu
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Chinnappan, Prithiv Kumar
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Shanmugam, Vishal
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Zeyu, Lin
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Hulme-Smith, Christopher
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Process and geometrical integrity optimization of electron beam melting for copper2022In: CIRP annals, ISSN 0007-8506, E-ISSN 1726-0604, Vol. 71, p. 201-204Article in journal (Refereed)
    Abstract [en]

    This work systematically analyzes and optimizes the process of electron beam melting for pure copper. It is shown that, for reliable manufacturing, the preheating temperature should be optimized to avoid porosity as well as part deformation. The electron beam should be fully focused to prevent shrinkage voids (correlated to negative defocusing) and material spattering (linked to positive defocusing). Smoother surfaces from lower hatch spacing (e.g., 100µm) can improve the density reliability, while longer overhangs are reached by a higher hatch spacing. A suitable starting contour strategy is also applied to mitigate border porosities, reduce side roughness and increase geometric precision.

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  • 7.
    Daemi, Bita
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Tomkowski, Robert
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Archenti, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Centres, Design and Management of Manufacturing Systems, DMMS. KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    High precision 3D evaluation method for Vickers hardness measurement2020In: CIRP annals, ISSN 0007-8506, E-ISSN 1726-0604Article in journal (Refereed)
    Abstract [en]

    Hardness measurement is a vital step for quality assurance in manufacturing of a wide range of products. Today, the standard hardness measurement tests, such as Vickers, are based on microscope image-based evaluation methods. Since these methods are limited to the geometry of the indentation in 2D images, their precision are highly dependent on the samples’ surface finish. A novel method based on 3D surface topography of the indentation is introduced for more robust Vickers hardness measurement. The 3D evaluation method with information in Z direction offers a high level of precision in hardness measurement on surfaces with different surface qualities.

  • 8.
    de Giorgio, Andrea
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Cacace, Stefania
    Department of Mechanical Engineering, Politecnico di Milano, Via La Masa 1, 20156 Milan, Italy.
    Maffei, Antonio
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Monetti, Fabio Marco
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Digital Smart Production.
    Roci, Malvina
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Onori, Mauro
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Sustainable Production Systems.
    Assessing the influence of expert video aid on assembly learning curves2021In: Article in journal (Refereed)
    Abstract [en]

    Since the introduction of the concept of learning curves in manufacturing, many articles have been applying the model to study learning phenomena. In assembly, several studies present a learning curve when an operator is trained over a new assembly task; however, when comparisons are made between learning curves corresponding to different training methods, unaware researchers can show misleading results. Often, these studies neglect either or both the stochastic nature of the learning curves produced by several operators under experimental conditions, and the high correlation of the experimental samples collected from each operator that constitute one learning curve. Furthermore, recent studies are testing newer technologies, such as assembly animations or augmented reality, to provide assembly aid, but they fail to observe deeper implications on how these digital training methods truly influence the learning curves of the operators. This article proposes a novel statistical study of the influence of expert video aid on the learning curves in terms of assembly time by means of functional analysis of variance (FANOVA). This method is better suited to compare learning curves than common analysis of variance (ANOVA), due to correlated data, or graphical comparisons, due to the stochastic nature of the aggregated learning curves. The results show that two main effects of the expert video aid influence the learning curves: one in the transient and another in the steady state of the learning curve. The transient effect of the expert video aid, where the statistical tests suffer from a high variance in the data, appears to be a reduction in terms of assembly time for the first assemblies: the operators seem to benefit from the expert video aid. As soon as the steady state is reached, a slower and statistically significant effect appears to favor the learning processes of the operators who do not receive any training aid. Since the steady state of the learning curves represents the long term production efficiency of the operators, the latter effect might require more attention from industry and researchers.

  • 9.
    de Giorgio, Andrea
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Cacace, Stefania
    Politecn Milan, Dept Mech Engn, Via La Masa 1, I-20156 Milan, Italy..
    Maffei, Antonio
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Monetti, Fabio Marco
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Digital Smart Production.
    Roci, Malvina
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Onori, Mauro
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Sustainable Production Systems.
    Assessing the influence of expert video aid on assembly learning curves2022In: Journal of manufacturing systems, ISSN 0278-6125, E-ISSN 1878-6642, Vol. 62, p. 263-269Article in journal (Refereed)
    Abstract [en]

    Since the introduction of the concept of learning curves in manufacturing, many articles have been applying the model to study learning phenomena. In assembly, several studies present a learning curve when an operator is trained over a new assembly task; however, when comparisons are made between learning curves corresponding to different training methods, unaware researchers can show misleading results. Often, these studies neglect either or both the stochastic nature of the learning curves produced by several operators under experimental conditions, and the high correlation of the experimental samples collected from each operator that constitute one learning curve. Furthermore, recent studies are testing newer technologies, such as assembly animations or augmented reality, to provide assembly aid, but they fail to observe deeper implications on how these digital training methods truly influence the learning curves of the operators. This article proposes a novel statistical study of the influence of expert video aid on the learning curves in terms of assembly time by means of functional analysis of variance (FANOVA). This method is better suited to compare learning curves than common analysis of variance (ANOVA), due to correlated data, or graphical comparisons, due to the stochastic nature of the aggregated learning curves. The results show that two main effects of the expert video aid influence the learning curves: one in the transient and another in the steady state of the learning curve. The transient effect of the expert video aid, where the statistical tests suffer from a high variance in the data, appears to be a reduction in terms of assembly time for the first assemblies: the operators seem to benefit from the expert video aid. As soon as the steady state is reached, a slower and statistically significant effect appears to favor the learning processes of the operators who do not receive any training aid. Since the steady state of the learning curves represents the long term production efficiency of the operators, the latter effect might require more attention from industry and researchers.

  • 10.
    Gonzalez, Monica
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Hosseini, Arian
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Design (Div.).
    Theissen, Nikolas Alexander
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Archenti, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Centres, Design and Management of Manufacturing Systems, DMMS. KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems. KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Sustainable Production Systems. KTH, School of Industrial Engineering and Management (ITM), Sustainable production development, Processledning och hållbar produktion.
    Quasi-static loaded circular testing of serial articulated industrial manipulators2020In: 52nd International Symposium on Robotics, ISR 2020, VDE Verlag GmbH , 2020, p. 1-6Conference paper (Refereed)
    Abstract [en]

    This research outlines the methodology and application of quasi-static loaded circular testing on serial articulated industrial robots using the Loaded Double Ball Bar (LDBB). The article focuses on measuring the quasi-static path accuracy and repeatability of industrial manipulators to evaluate their performance in industrial contact applications such as trimming, grinding, or deburring. The manipulator is measured under quasi-static loads of 100, 350, 500, and 600N using circular testing following the guidelines of ISO 230-4. The data can be used to discuss core aspects of process planning with industrial manipulators such as workpiece placement, optimal robot pose selection for dexterity as well as stiffness optimization. The article contains a case study of quasi-static loaded circular testing of a mid-size articulated industrial robot from ABB using the LDBB and a Leica AT960 laser tracker for validation. At a load of 600N the path accuracy for both Clock-Wise (CW) and Counter Clock-Wise (CCW) were 2:4 mm, measured with the LDBB, compared to 2.9 mm, measured with the AT960. Finally, the paper ends with a discussion about the opportunities and challenges for the implementation of loaded circular testing for elasto-geometrical calibration of industrial manipulators. 

  • 11.
    Gonzalez, Monica
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Peukert, Bernd
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Theissen, Nikolas Alexander
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Archenti, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Production engineering, Manufacturing and Metrology Systems.
    Experimental identification of the position-dependent dynamics of an industrial manipulator2021In: Proceedings of the 21st International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2021, 2021, p. 235-238Conference paper (Refereed)
    Abstract [en]

    Industrial manipulators are desired to be commonly used for material removal applications due to their high flexibility, low cost, and large working space. However, their lower stiffness (compared to a machine tool) leads to a reduction in path accuracy. This reduction directly affects the dimensional accuracy of the machined part. Additionally, the low stiffness in the presence of dynamic process forces creates vibrations influencing the surface quality, tool life, and service life of the manipulator. Static stiffness models, optimization, and compensation techniques exist to minimize force-induced deflections. Multi-body dynamics analytical models still lack the required accuracy in predicting the position-dependent dynamics of the manipulator. Dynamics data-driven models are rising to tackle the uncertainties in modeling the robot properties. This study presents the position-dependent variation of the dynamic characteristics, namely frequency and damping, of a mid-size articulated industrial manipulator, which were determined through experimental modal analysis. The position-dependent dynamics is investigated and quantified in a low-frequency range and is discretely measured and presented in two perpendicular planes (horizontal and vertical) of the robot working space. The study concludes with a discussion on the potential to apply the dynamic information obtained experimentally for the process planning and working space optimization in contact applications. 

  • 12.
    Gonzalez, Monica
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Theissen, Nikolas Alexander
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Barrios, Asier
    Archenti, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Online compliance error compensation system for industrial manipulators in contact applications2022In: Robotics and Computer-Integrated Manufacturing, ISSN 0736-5845, E-ISSN 1879-2537, Vol. 76, p. 102305-102305, article id 102305Article in journal (Refereed)
    Abstract [en]

    Industrial manipulators are rarely used in high-force processes even though they provide flexibility, adaptability, relatively low cost, and a large workspace. This limited utilization is mainly due to their inherent low stiffness, which results in significant deformation. Hence, it is necessary to improve their accuracy in order to achieve high-precision requirements while performing tasks under load. This paper focuses on the development and implementation of an online compliance error compensation system for industrial manipulators. The proposed algorithm computes the compensation based on an elasto-geometric robot model and process forces measured with a force sensor mounted between the robot mechanical interface and the end effector. The performance of the compensation system is evaluated experimentally in two high payload robots from different manufacturers in which the compensation was carried out to reduce the mean deformation of circular trajectories under load.

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    fulltext
  • 13.
    Ibaraki, Soichi
    et al.
    Hiroshima University.
    Theissen, Nikolas Alexander
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Archenti, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Alam, Md. Moktadir
    Hiroshima University.
    Evaluation of Kinematic and Compliance Calibrationof Serial Articulated Industrial Manipulators2021In: International Journal of Automation Technology, ISSN 1881-7629, E-ISSN 1883-8022, Vol. 15, no 5, p. 567-580Article in journal (Refereed)
    Abstract [en]

    As long as industrial robots are programmed by teachprogramming, their positioning accuracy is unimportant.With a wider implementation of offline programmingand new applications such as machining, ensuringa higher positioning accuracy of industrial robotsover the entire working space has become very important.In this paper, we first review the measurementschemes of end effector poses. We then outline kinematicmodelsof serial articulated industrialmanipulatorsto quantify the positioning accuracy with a focuson the extension of the classical Denavit-Hartenberg(DH) models to include rotary axis error motions.Subsequently, we expand the discussion on kinematicmodels to compliant robot models. The review highlightscompliance models that are applied to calculatethe elastic deformation produced by forces, namelygravity and external loads. Model-based numericalcompensation plays an important role in machine toolcontrol. This paper aims to present state-of-the-arttechnical issues and future research directions for theimplementation of model-based numerical compensationschemes for industrial robots.

  • 14. Jadhav, Suraj Dinkar
    et al.
    Dhekne, Pushkar Prakash
    Brodu, Etienne
    Van Hooreweder, Brecht
    Dadbakhsh, Sasan
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems. KU Leuven, Department of Mechanical Engineering, & Member of Flanders Make, Celestijnenlaan 300, B-3001 Heverlee, Belgium.
    Kruth, Jean-Pierre
    Van Humbeeck, Jan
    Vanmeensel, Kim
    Laser powder bed fusion additive manufacturing of highly conductive parts made of optically absorptive carburized CuCr1 powder2021In: Materials & design, ISSN 0264-1275, E-ISSN 1873-4197, Vol. 198Article in journal (Refereed)
    Abstract [en]

    Fabrication of fully dense and highly conductive copper alloy parts via laser-based additive manufacturing (L-AM) is challenging due to the high optical reflectivity of copper at λ = 1060 – 1080 nm and high thermal conductivity. To overcome this, the use of optically absorptive surface-modified copper powders is being evaluated in the laser powder bed fusion (LPBF) process. Although the surface-modified powders exhibit high optical absorption at room temperature, not all of them allow the fabrication of fully dense parts at a laser power below 500 W. Accordingly, this article proposes the use of optically absorptive carburized CuCr1 powder for the consistent fabrication of copper parts. Moreover, a densification mechanism of parts is discussed to explain the distinct LPBF processing behavior of different surface-modified powders, such as carburized CuCr1 and carbon mixed CuCr1 powders, albeit having similar room temperature optical absorption. This investigation clearly outlines the advantage of a firmly bonded modified layer present on the surface of the carburized CuCr1 powder over a loosely attached carbon nanoparticle layer present in the carbon-mixed CuCr1 powder. Apart from the successful fabrication of CuCr1 parts, fabricated parts are subjected to two different post-heat treatments, and it is shown that the final properties can be customized by applying tailored post-heat treatments.

  • 15. Jadhav, Suraj Dinkar
    et al.
    Dhekne, Pushkar Prakash
    Dadbakhsh, Sasan
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Kruth, Jean-Pierre
    Van Humbeeck, Jan
    Vanmeensel, Kim
    Surface Modified Copper Alloy Powder for Reliable Laser-based Additive Manufacturing2020In: Additive Manufacturing, ISSN 2214-8604, E-ISSN 2214-7810, Vol. 35, article id 101418Article in journal (Refereed)
    Abstract [en]

    Owing to the high optical reflectivity of copper, silver, and gold in the infrared region, high laser power is required for laser-based additive manufacturing (L-AM). This increases the risk of damaging the laser optics due to sustained back-reflections and renders L-AM of reflective metals an unsustainable technology. To tackle this issue, a novel, industrially upscalable powder surface modification method is proposed and validated using a CuCr1 alloy. The surface of CuCr1 powder is modified by the outward diffusion of chromium in a nitrogen atmosphere, forming a rim around the powder particles. This doubled the optical absorption of the powder. Consequently, a mere 20% of the laser energy is required to process the surface-modified powder by laser powder bed fusion compared to the virgin CuCr1 powder. The fabricated parts demonstrate a very high thermal conductivity of 370 ± 15 W/(m·K) and tensile strength of 439 ± 19 MPa, after applying a suitable post-heat treatment.

  • 16.
    Kokare, Samruddha
    et al.
    KTH.
    Abdullah Asif, Farazee Mohammad
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Mårtensson, Gustaf
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Shoaib-ul-Hasan, Sayyed
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Rashid, Amir
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Roci, Malvina
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Salehi, Niloufar
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    A comparative life cycle assessment of stretchable and rigid electronics: a case study of cardiac monitoring devices2021In: International Journal of Environmental Science and Technology, ISSN 1735-1472, E-ISSN 1735-2630Article in journal (Refereed)
    Abstract [en]

    Stretchable electronics is a new innovation and becoming popular in various fields, especially in the healthcare sector. Since stretchable electronics use less printed circuit boards (PCBs), it is expected that the environmental performance of a stretchable electronics-based device is better than a rigid electronics-based device that provides the same functionalities. Yet, such a study is rarely available. Thus, the main purpose of this research is to perform a comparative life cycle analysis of stretchable and rigid electronics-based devices. This research combines both the case study approach and the research review approach. For the case study, a cardiac monitoring device with both stretchable and rigid electronics is used. The ISO 14044:2006 standard's prescribed LCA approach and ReCiPe 2016 Midpoint (Hierarchist) are followed for the impact assessment using the SimaPro 9.1 software. The LCA results show that the stretchable cardiac monitoring device has better environmental performance in all eighteen impact categories. This research also shows that the manufacturing process of stretchable electronics has lower environmental impacts than those for rigid electronics. The main reasons for the improved environmental performance of stretchable electronics are lower consumption of raw material as well as decreased energy consumption during manufacturing. Based on the LCA results of a cardiac monitoring device, the study concludes that stretchable electronics and their manufacturing process have better environmental performance in comparison with the rigid electronics and their manufacturing process.

  • 17.
    Laspas, Theodoros
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Theissen, Nikolas Alexander
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Archenti, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Novel methodology for the measurement and identification for quasi-static stiffness of five-axis machine tools2020In: Precision Engineering, ISSN 0141-6359, Vol. 65, p. 164-170Article in journal (Refereed)
    Abstract [en]

    Stiffness is an important characteristic of production machinery, as it contributes to its ability to precisely maintain the pose between a tool center point with respect to a workpiece under load. For machine tools, it directly affects the geometric dimensions and surface properties of the parts, i.e. how closely the parts match their design drawings. This work presents a novel measurement procedure to measure and identify full translational stiffness matrices of 5-axis machining centers using quasi-static circular trajectories. The measurement procedure consists of inducing quasi-static loads, which vary in magnitude and direction, at the tool center point of the machine tool using the Loaded Double Ball Bar and measuring the displacement with three Linear Variable Differential Transformers while the spindle tracks the circular trajectories inscribed by the movement of the rotary axis. The work outlines and quantifies the main components of the uncertainty budget related to the measurement of the translational stiffness matrices. The measurement procedure is implemented in a case study on a 5-axis machining center. Finally, the manuscript concludes with a discussion on the utility value of the translational stiffness matrix for the design and operation of machine tools as well as the possibility to expand the measurement procedure to a calibration procedure for 5-axis machining centers to analyze the translational and rotational stiffness.

  • 18.
    Lin, Zeyu
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Zhao, Xiaoyun
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Dadbakhsh, Sasan
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Rashid, Amir
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Evaluating the electron beam spot size in electron beam melting machines2021Conference paper (Refereed)
    Abstract [en]

    Since electron beam (EB) is the main additive manufacturing (AM) tool in electron beam melting (EBM), EB spot size plays a significant role in the parts quality, surface roughness as well as the microstructure and corresponding properties. So far, the research on the relationship between the machine parameters and the EB spot size has been mainly based on the single track and powderless single track printing on a metal plate such as stainless steel. However, this method, due to material thermal properties as well as the melting phenomena, cannot reveal the actual value for the EB spot size. This research is carried out to establish a simple methodology on measuring the EB spot size in a more accurate way with a low cost. To do so, a ceramic surface coating was applied to the surface of a metal copper starting plate and stainless steel plate. Afterwards, the EB applied the tracks onto the coatings and regular metal plate. The analysis showed that the EB tracks on ceramic coated stainless steel plates could be the best replica for the electron beam among those materials tested in this work.  

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  • 19. Malakizadi, Amir
    et al.
    Mallipeddi, Dinesh
    Dadbakhsh, Sasan
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    M'Saoubi, Rachid
    Krajnik, Peter
    Post-processing of additively manufactured metallic alloys – A review2022In: International journal of machine tools & manufacture, ISSN 0890-6955, E-ISSN 1879-2170, ISSN 0890-6955, Vol. 179, no 103908Article in journal (Refereed)
    Abstract [en]

    Additive manufacturing (AM) is characterised by several unique advantages, such as (freedom of) design, capability of fusing dissimilar materials, near-net-shape, and achieving a more sustainable production. While the increased precision of metal AM in recent years reduced the needed amount of post-processing to meet dimensional tolerance, the requirements for functional surfaces necessitate a well-understood post-processing, ranging from heat treatment to machining and finishing. The inherently rough initial (as-built) surface topography next to complex material microstructure affects the capability of post-processing/finishing operations to smooth the surface texture and obtain a favourable surface integrity. In this respect, a more fundamental understanding of the effects of material properties on post-processing/finishing is needed. Therefore, this review paper aims to establish the relationship between the characteristics of different AM technologies, microstructural properties of materials in as-built and heat-treated conditions, and the physical properties influencing the response of additively manufactured materials during post-processing/finishing operations. In particular, emphasis is placed on the physics-based understanding of how the microstructural characteristics of 316L, Ti6Al4V and Alloy 718 produced using the two principal technologies, Powder Bed Fusion (PBF) and Direct Energy Deposition (DED), influence their mechanical properties like tensile strengths, hardness and ductility. These properties are among the key factors influencing the response of material during post-processing/finishing operations involving material removal by shear deformation. This review paper also discusses the role of post-processing/finishing on fatigue performance, tribological behaviour and corrosion resistance of investigated AM materials. The paper summarises the state-of the art of post-processing/finishing operations and future research trends are highlighted.

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  • 20.
    Mansour, Rami
    et al.
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics, Vehicle Engineering and Solid Mechanics, Solid Mechanics.
    Gillgren, Sara
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics, Vehicle Engineering and Solid Mechanics, Solid Mechanics.
    Dadbakhsh, Sasan
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Topology Optimization for Additive Manufacturing – A Numerical Study of Current Design Framework Capabilities and Limitations2022In: Advances in Transdisciplinary Engineering / [ed] A.H.C. Ng et al., IOS Press , 2022, Vol. 21, p. 592-603Conference paper (Refereed)
    Abstract [en]

    Topology optimization (TO) is commonly used to minimize the weight of a structural component subject to a constraint on the maximum equivalent stress. In TO for additive manufacturing (AM), constraints on the build direction as well as the overhang angle are also included in the optimization. However, current design framework generally doesn’t include the residual stresses and distortions that result from the AM process directly into the TO. In this work, it is shown that this limitation can result in components that may fail during the Selective Laser Melting (SLM) due to high stresses and distortion that were not accounted for in the TO. For the studied demonstrative bracket design from Ti-6Al-4V, it is shown that the spatial stress distribution, including both the location and magnitude of the maximum stress, is strongly altered after SLM compared to the stresses used in the TO, even after heat treatment. This work highlights the importance of integrating AM process simulation with residual stress and distortion prediction directly in the TO, which is currently a difficult and computationally inefficient task.

  • 21.
    Peukert, Bernd
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Archenti, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems. KTH, School of Industrial Engineering and Management (ITM), Sustainable production development.
    A modular node-based modeling platform for the simulation of machining processes2021In: Proceedings of the 21st International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2021, euspen , 2021, p. 351-354Conference paper (Refereed)
    Abstract [en]

    Increasing precision requirements motivate research on the system perspective of machining systems. Virtual environments for the prediction of the Process Machine Interaction (PMI) are one key to obtain a priori understanding of machining accuracy, save expensive testing and planning time of industrial users, and increase the overall resource utilization. This paper introduces the modular node-based software platform SharpCut (#cut). The platform follows a sequential modeling approach of manufacturing processes and machine tools by using nodes. The novelty of the method lies in its open architecture with a strong focus on extendibility, adaptability, and research applicability. Besides the node-based modeling approach, four implemented software modules are described. The four modules are the workpiece discretization, the tool and cutting inserts, the material removal, and the system's kinematics. The machine tool's motion and kinematic errors are modeled with Homogeneous Transformation Matrices (HTMs). The workpiece discretization is performed with a memory-efficient implementation of Depth Elements (Dexels). The material removal follows from the modelling of the Tool-Workpiece Engagement (TWE) with a generic model of the tool and the computationally efficient MÖLLER-TRUMBORE ray-triangle intersection algorithm. With the presented modules, it is possible to predict the results of machining processes and perform sensitivity or root cause analyses. The paper concludes with an example model and simulation of a face-milling process.

  • 22.
    Peukert, Bernd
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Archenti, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Dynamic Interaction Between Precision Machine Tools and Their Foundations2020In: International Journal of Automation Technology, ISSN 1881-7629, E-ISSN 1883-8022, Vol. 14, no 3, p. 386-398Article in journal (Refereed)
    Abstract [en]

    The manufacturing accuracy of modern machine tools strongly depends on the placement of the machine tool structure on the factory’s foundation. Civil engineering knows a variety of foundation types and factory planners must carefully consider local circumstances such as the size and the properties of the regional subsoil as well as the individual requirements of machine tools. Two of the major reasons for the effect of the foundation onto the machining accuracy are the added stiffness and the increased mass from the installation site’s foundation. A change of these characteristics greatly affects the dynamic characteristics of the overall machine tool and therefore also the machining dynamics. Although some general rules and guidelines exist for the design of foundations, their dynamic interaction with the supported precision machine tool structures is not well understood yet. This paper presents a series of measurements on two different types of machine tool foundations and highlights the characteristic differences in their dynamic interaction. It also proposes a novel approach to validate the conclusions with the use of foundation and machine tool scale models. These results can serve factory planners of precision targeting shop floors as a valuable guide for deciding on a suitable foundation for lowering the individual machine tool vibrations and/or reducing the dynamic interaction between closely located machine tools.

  • 23.
    Rashid, Amir
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Guo, Shuai
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Adane, Tigist Fetene
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Nicolescu, Mihai
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Advanced multi-functional coatings for vibration control of machining2020In: Journal of Machine Engineering, ISSN 1895-7595, Vol. 20, no 1, p. 5-23Article in journal (Refereed)
    Abstract [en]

    The paper present theoretical and experimental studies of the energy dissipation performance of a composite structure composed in a multilayer nano-composite damping coating applied on a tungsten carbide shim and placed beneath the cutting insert. The coated shim placed closed to the cutting zone is subjected to high compressive and shear stresses as well as high temperature. Therefore, apart from high damping capacity it requires high stiffness and high thermal resistance. The coated shim dissipates the high frequency oscillations produced at the tool-chip and tool-workpiece interfaces during the chip forming process. The use of coated shims demonstrates that the tool life is considerably extended, while the machined surface integrity is improved. The Reuss model of the composite structure composed of a phase with a stiff, low loss factor and a phase with high loss factor is used to calculate the optimal coating thickness that gives high loss factor combined with high stiffness. The synthesis process of the coating material using HiPIMS process is discussed. The physical characteristics of the coating and the machining performance are presented in the experimental section.

  • 24.
    Rashid, Masud-Ur
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Tomkowski, Robert
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Archenti, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Effect of Surface Pre-Treatment on the Adhesion between HiPIMS Thick Cu:CuCNx Coating and WC-Co Shim2022In: Coatings, ISSN 2079-6412, Vol. 12, no 10, article id 1484Article in journal (Refereed)
    Abstract [en]

    High-power impulse magnetron-sputtering thick metal/carbon-nitride-doped metal-matrix multilayer nano-composite coating can be applied to cutting-tool holder components to improve cutting insert's life. One of the challenges of such an add-on solution is the poor adhesion between the thick coating and the hard alloy substrate, such as WC-Co shim. This work presents a study on WC-Co substrate surface preparation methods for HiPIMS coating and its adhesion improvement. Three mechanical surface pretreatment methods were investigated: machining (grinding), diamond polishing, and grit blasting. White-light interferometry was used for substrate surface texture measurement before and after pretreatment. It was demonstrated that, compared to machining and diamond polishing, grit blasting can significantly improve the interface adhesion between the similar to 200 mu m-thick Cu:CuCNx coating and WC-Co shim. Grit blasting was also found to be beneficial for improving the cutting insert's life in the external turning process. In turning tests, the coating lifetime for grit-blasted shim was more than 90 min, whereas the coating lifetimes for machined shim (conventional shim) and diamond-polished shim were similar to 85 min and similar to 70 min, respectively. Further, by comparing the HiPIMS gradient chromium pre-layer between the coating and substrate for the different shims, the study also explained that the quasi-isotropic surface texture of grit-blasted shim is more advantageous for coating-substrate interface adhesion.

  • 25.
    Roci, Malvina
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Circular Manufacturing Systems: Complex systems modelling and simulation for enhanced decision-making2022Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    A transition towards circular manufacturing systems (CMS) has brought awareness of untapped economic and environmental benefits for the manufacturing industry. Despite this increased interest, the implementation of CMS is still in its infancy stage. To support the manufacturing industry in implementing CMS in practice, this research seeks to (1) explore the main characteristics of CMS and their needs for a successful implementation in the context of the manufacturing industry, and (2) develop quantitative analysis tools to support decision-making in implementing CMS with a concurrent focus on economic and environmental performance. By viewing CMS as complex adaptive systems (CAS), this research proposes to exploit complex system modelling and simulation used in the study of CAS to characterise, model, and analyse CMS. In this regard, a multi-method simulation model architecture that combines features of agent-based, discrete-event, and system dynamics modelling methods is proposed to model and simulate CMS as different abstraction levels are needed to capture the complex and dynamic interactions among the elements of the system. The resulting multi-method simulation tool aims at providing systemic quantification of CMS in terms of economic performance (e.g., lifecycle costs, lifecycle revenues, and lifecycle profits), environmental performance (e.g., lifecycle environmental impact), and technical performance (e.g., quality, quantity and timing of product return flows), and therefore, facilitates decision-making for industrial organizations implementing CMS in practice.

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  • 26.
    Roci, Malvina
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Abdullah Asif, Farazee Mohammad
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Circular manufacturing systems2020In: Handbook of the Circular Economy / [ed] Miguel Brandão, David Lazarevic and Göran Finnveden, Edward Elgar Publishing, 2020, p. 343-357Chapter in book (Refereed)
    Abstract [en]

    Manufacturing industry is a major consumer of the energy and material resources generating significant amount of waste. Circular manufacturing systems (CMS) that are designed intentionally for closing the loop of products for reuse, maintaining their original performance at the least, through multiple lifecycles are indispensable for sustainable development. For successful implementation of CMS, a systemic approach for integration of business model, product design and supply chains exploiting Information and Communication Technology (ICT) a vital enabler is essential. In CMS, the business model is a primary driver dictating the design of both products and supply chains. While these three functions influence each other in diverse ways, they also define needs and requirements for ICT infrastructure for handling the complexity of information management throughout the value chain. Several leading industrial practices across the manufacturing landscape are representative examples of CMS, where the systemic approach of integrating business model, product design, supply chain and ICT is taken into consideration. Prominent examples of such approach include companies like Xerox, Ricoh, Caterpillar, HP, Renault and Michelin. This chapter explores the concept of CMS, their characteristics and need in the context of circular economy. It also analyses leading examples of CMS implementation in the current linear economy paradigm and challenges in scaling up to realise their full business and sustainability potential.

  • 27.
    Roci, Malvina
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Abdullah Asif, Farazee Mohammad
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Lieder, Michael
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Rashid, Amir
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Mihelič, Aleš
    Gorenje Gospodinjski Aparati d.d, Partizanska Cesta 12, 3320, Velenje, Slovenia.
    Kotnik, Simon
    Gorenje Gospodinjski Aparati d.d, Partizanska Cesta 12, 3320, Velenje, Slovenia.
    A methodological approach to design products for multiple lifecycles in the context of circular manufacturing systems2021In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 296, p. 126534-, article id 126534Article in journal (Refereed)
    Abstract [en]

    It is estimated that the adaptation of the Circular Economy approach can yield material cost savings of hundreds of billions of dollars per year for the EU and can result in huge environmental benefits. To tap this potential, the manufacturing industry needs to take a circular approach, where the products are designed intentionally to be used for multiple lifecycles. However, there is a lack of methodologies to date that can support such an approach. To fill this gap, this research has proposed a novel methodological approach that can support designing products for multiple lifecycles to keep the products as well as the components and the materials at their highest utility and value at all times. This research has identified that there is a strong synergy among the concepts of product design strategies, product obsolescence and product end-of-life options. Taking this synergy as the foundation and adopting modular architectures in the product design and development process, lifecycle planning can be performed for products that will sustain multiple lifecycles. This research is performed in two steps: first, the research review process is used to explore the knowledge base in the field of product design methodologies and based on the insights from the literature a novel methodological approach is proposed; second, a case example is used to demonstrate the applicability and effectiveness of the proposed methodological approach.

  • 28.
    Roci, Malvina
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Rashid, Amir
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Economic and environmental impact of circular business models: A case study of White Goods-as-a-Service using multi-method simulation modelling2023In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 407, article id 137147Article in journal (Refereed)
    Abstract [en]

    Circular business models are gaining traction in academia and industry as an instrument to deliver environmental benefits while being economically profitable. Despite this increased interest, studies that quantitatively assess the impact of circular business models are limited. This study provides researchers and practitioners with a quantitative analysis tool to assess the dynamics of circular business models from both an economic and environmental perspective. Using the case study of white goods-as-a-service, this study employs multi-method simulation modelling in combination with statistical design and analysis of simulation experiments to investigate the effect of different factors including payment schemes (i.e., fixed fee, pay-per-use, and hybrid) and subscription contract duration (i.e., long-term, mid-term, and short-term) on the economic and environmental performance of access-based models. In addition, as the adoption of access-based models is economically challenging for manufacturers due to a discrepancy between costs and revenue streams, this study analyses the effect of different levers to improve the liquidity performance of access-based business models including deposit schemes, cancellation and collection fees, as well as partnering with financial institutions to cover the initial revenue gap. 

  • 29.
    Roci, Malvina
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Salehi, Niloufar
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Amir, Saman
    Abdullah Asif, Farazee Mohammad
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Shoaib-ul-Hasan, Sayyed
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Rashid, Amir
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Multi-method simulation modelling of circular manufacturing systems for enhanced decision-making2022In: MethodsX, ISSN 1258-780X, E-ISSN 2215-0161, Vol. 9, p. 101709-101709, article id 101709Article in journal (Refereed)
    Abstract [en]

    Circular manufacturing systems (CMS) constitute complex value networks comprising a large and diverse set of stakeholders that collaborate to close the loop of products through multiple lifecycles. Complex systems modelling and simulation play a crucial role in providing quantitative and qualitative insights into the behaviour of such systems. In particular, multi-method simulation modelling that combines agent-based, discrete-event, and system dynamics simulation methods is considered more suitable to model and simulate CMS as it allows to capture their complex and dynamic nature. This paper provides a step-by-step approach on how to build a CMS multi-method simulation model in order to assess their economic, environmental, and technical performance for enhanced decision-making. To model and simulate CMS three main elements need to be considered: • A multi-method model architecture where the CMS stakeholders with heterogeneous characteristics are modelled individually as autonomous agents using agent-based, discrete-event, and system dynamics. • An agent environment defined by a Geographic Information System (GIS) to establish connections based on agents’ geographic location. • The product journey resulting from the product's interaction with various CMS stakeholders in the circular value network is traced throughout its multiple lifecycles.

  • 30.
    Roci, Malvina
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Salehi, Niloufar
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Amir, Saman
    Shoaib-ul-Hasan, Sayyed
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Abdullah Asif, Farazee Mohammad
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Mihelič, Aleš
    Rashid, Amir
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Towards Circular Manufacturing Systems implementation: A Complex Adaptive Systems perspective using modelling and simulation as a quantitative analysis tool2022In: Sustainable Production and Consumption, ISSN 2352-5509, Vol. 31, p. 97-112Article in journal (Refereed)
    Abstract [en]

    A transition towards circular manufacturing systems (CMS) has brought awareness of untapped economic and environmental benefits for the manufacturing industry. Conventional manufacturing systems already present a high level of complexity in terms of physical flows of materials and products as well as information and financial flows linked to them. Closing the loop of materials and products through multiple lifecycles, as proposed in CMS, increases this complexity manifold. To support practitioners in implementing CMS through enhanced decision-making, this research studies CMS from a complex adaptive systems (CAS) perspective and proposes to exploit methods and tools used in the study of CAS to characterise, model and analyse CMS. By viewing CMS as CAS composed of autonomous, interacting agents, this research proposes a multi-method model architecture for modelling and simulating CMS. The different CMS stakeholders are modelled individually as autonomous agents by integrating agent-based, discrete-event, and/or system dynamics modules within each agent to capture their diverse and heterogeneous nature. The applicability of the proposed multi-method approach is illustrated through a case study of a white goods manufacturing company implementing CMS in practice. This case study shows the relevance and feasibility of the proposed multi-method approach as a decision support tool for the systemic exploration and quantification of CMS. It also shows how a transition towards CMS necessitates a lifecycle approach in terms of costs, revenues and environmental impacts to identify hotspots and, therefore, design circular systems that are viable in both economic and environmental terms. In fact, the analyses of the simulation results indicate how decisions in terms of business models, product design, and supply chain affected the CMS performance of the case company. For instance, implementing a service-based model led to a high number of usecycles (on average six usecycles per washing machine), which, in turn, led to high lifecycle costs and emissions due to more frequent transportation and recovery operations. Similarly, the deployment of long-lasting washing machines, which is a core principle of CMS, led to high manufacturing costs. Due to the high initial costs and a time mismatch between revenues and costs in the service-based model, it required a longer time for the company to reach the break-even point (approximately 23 months). Overall, the case study shows that multi-method simulation modelling can provide decision-making support for a successful implementation of CMS.

  • 31.
    Shoaib-ul-Hasan, Sayyed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Roci, Malvina
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Asif, Farazee M. A.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Salehi, Niloufar
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Rashid, Amir
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Analyzing Temporal Variability in Inventory Data for Life Cycle Assessment: Implications in the Context of Circular Economy2021In: Sustainability, E-ISSN 2071-1050, Vol. 13, no 1, article id 344Article in journal (Refereed)
    Abstract [en]

    Life cycle assessment (LCA) is used frequently as a decision support tool for evaluating different design choices for products based on their environmental impacts. A life cycle usually comprises several phases of varying timespans. The amount of emissions generated from different life cycle phases of a product could be significantly different from one another. In conventional LCA, the emissions generated from the life cycle phases of a product are aggregated at the inventory analysis stage, which is then used as an input for life cycle impact assessment. However, when the emissions are aggregated, the temporal variability of inventory data is ignored, which may result in inaccurate environmental impact assessment. Besides, the conventional LCA does not consider the environmental impact of circular products with multiple use cycles. It poses difficulties in identifying the hotspots of emission-intensive activities with the potential to mislead conclusions and implications for both practice and policy. To address this issue and to analyze the embedded temporal variations in inventory data in a CE context, the paper proposes calculating the emission intensity for each life cycle phase. It is argued that calculating and comparing emission intensity, based on the timespan and amount of emissions for individual life cycle phases, at the inventory analysis stage of LCA offers a complementary approach to the traditional aggregate emission-based LCA approach. In a circular scenario, it helps to identify significant issues during different life cycle phases and the relevant environmental performance improvement opportunities through product, business model, and supply chain design.

  • 32.
    Szipka, Karoly
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Dax, Paul
    Archenti, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Degen, Florian
    Mikael, Hedlind
    Scania CV AB.
    Integration of machining system capability information into a CAx software environment for complex tool trajectory prediction2018In: Procedia CIRP, ISSN 2212-8271, E-ISSN 2212-8271, Vol. 72, p. 1239-1244Article in journal (Refereed)
    Abstract [en]

    Integration of machine tool specific capability information related to a manufactured part’s accuracy can significantly support the decision-making in production, help to understand root-cases of quality loss and optimize cutting processes. In this paper, a systematic methodology is proposed to bridge the gap between machine tool specific capability and finished part’s accuracy. For this purpose, a measurement-based model is implemented in a CAx software environment for the prediction of geometrical deviations in complex milling processes. Results are presented in a case study to demonstrate errors on the workpiece level due to the quasi-static capabilities of a given machine tool.

  • 33.
    Theissen, Nikolas Alexander
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Gonzalez Bassante, Monica Katherine
    Barrios, Asir
    IDEKO S.COOP, Elgoibar, Spain.
    Archenti, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems. KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Sustainable Production Systems.
    Quasi-Static Compliance Calibration ofSerial Articulated Industrial Manipulators2021In: International Journal of Automation Technology, ISSN 1881-7629, E-ISSN 1883-8022, no 5, p. 590-598Article in journal (Refereed)
    Abstract [en]

    This article presents a procedure for the quasi-staticcompliance calibration of serial articulated industrialmanipulators. Quasi-static compliance refers to theapparent stiffness displayed by manipulators at lowvelocitymovements, i.e., from 50 to 250 mm/s. Thenovelty of the quasi-static compliance calibration procedurelies in the measurement phase, in which thequasi-static deflections of the manipulator’s end effectorare measured under movement along a circulartrajectory. The quasi-static stiffness might be amore applicable model parameter, i.e., representingthe actual manipulator more accurately, for manipulatorsat low-velocity movements. This indicates thatthe quasi-static robot model may yield more accurateestimates for the trajectory optimization comparedwith static stiffness in the implementation phase. Thisstudy compares the static and apparent quasi-staticcompliance. The static deflections were measured atdiscretized static configurations along circular trajectories,whereas the quasi-static deflections were measuredunder circular motion along the same trajectories.Loads of different magnitudes were inducedusing the Loaded Double Ball Bar. The static andquasi-static displacements were measured using a linearvariable differential transformer embedded in theLoaded Double Ball Bar and a Leica AT901 lasertracker. These measurement procedures are implementedin a case study on a large serial articulatedindustrial manipulator in five different positions of itsworkspace. This study shows that the measured quasistaticdeflections are bigger than the measured staticdeflections. This, in turn, indicates a significant differencebetween the static and apparent quasi-staticcompliance. Finally, the implementation of the modelparameters to improve the accuracy of robots and thechallenges in realizing cost-efficient compliance calibrationare discussed.

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    Theissen, Gonzalez et al. 2021 - Quasi-Static Compliance Calibration of Serial
  • 34.
    Theissen, Nikolas Alexander
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Gonzalez, Monica
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Laspas, Theodoros
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Archenti, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Centres, Design and Management of Manufacturing Systems, DMMS. KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems. KTH, School of Industrial Engineering and Management (ITM), Sustainable production development, Processledning och hållbar produktion.
    Comparison of measured static and quasi-static deflections of industrial manipulators2021In: Laser Metrology and Machine Performance XIV - 14th International Conference and Exhibition on Laser Metrology, Machine Tool, CMM and Robotic Performance, LAMDAMAP 2021, euspen , 2021, p. 36-42Conference paper (Refereed)
    Abstract [en]

    This work presents a comparison of the measured static and quasi-static deflections of industrial manipulators. For the measurement of the static deflections, the manipulator remains in static positions while for the quasi-static deflections the manipulator follows a circular trajectory. The static deflections are measured at discretised static configurations along circular trajectories while the quasi-static deflections are measured under circular motion along the same trajectories. Loads of different magnitudes were induced with the Loaded Double Ball Bar (LDBB). The static and quasi-static displacements are measured using a (Linear Variable Differential Transformer) LVDT embedded in the Loaded Double Ball Bar and a Leica AT901 laser tracker. These measurement procedures are implemented in a case study on a large-sized serial articulated industrial manipulator from ABB in three different positions of its workspace. The presented method shows that the measured quasi-static deflections are on average approximately 22% bigger than the measured static deflections. The quasi-static deflections are at most 32% bigger than the static deflections. Finally, the manuscript concludes with a discussion on how the measurement procedure could be used to analyse the difference between using the static stiffness and the apparent quasi-static stiffness of an industrial manipulator for trajectory optimisation.

  • 35.
    Theissen, Nikolas Alexander
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Gonzalez, Monica
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Laspas, Theodoros
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Archenti, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Sustainable production development.
    Measurement and identification of dynamic translational stiffness matrix on machine tools under static preloads2021In: Proceedings of the 21st International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2021, euspen , 2021, p. 527-530Conference paper (Refereed)
    Abstract [en]

    Dynamic stiffness is an important characteristic of production machinery, as it contributes to its ability to maintain the position of the tool centre point accurately and precisely under loads. For machine tools, it directly affects the geometric dimensions and surface properties of produced parts. This work presents a measurement procedure for identification of the full translational dynamic stiffness matrix for a single configuration of a machine tool under loaded conditions. The measurement procedure consists of inducing a static baseload with superimposed dynamic loads, which were controlled in magnitude and direction, at the tool centre point of the machine tool. The measurement procedure uses the Loaded Double Ball Bar and measures the dynamic displacement with three Non-Contact Capacitive Probes. The measurement procedure is implemented in a case study on a 5-axis machining centre. Finally, the manuscript concludes with a discussion on the utility value of the translational dynamic stiffness matrix for the design and operation of machine tools as well as the possibility to expand the measurement procedure to capture the dynamic stiffness using quasi-static movements of the machine tool.

  • 36.
    Theissen, Nikolas Alexander
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Gonzalez, Monica
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Laspas, Theodoros
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Archenti, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Centres, Design and Management of Manufacturing Systems, DMMS. KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems. KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Sustainable Production Systems. KTH, School of Industrial Engineering and Management (ITM), Sustainable production development, Processledning och hållbar produktion.
    Measurementand identification of dynamic translational stiffness matrix on machine tools understatic preloads2021Conference paper (Refereed)
    Abstract [en]

    Dynamic stiffness is an important characteristic of production machinery, as it contributes to its ability to maintain the position ofthe tool centre point accurately and precisely under loads. For machine tools, it directly affects the geometric dimensions and surfaceproperties of produced parts. This work presents a measurement procedure for identification of the full translational dynamicstiffness matrix for a single configuration of a machine tool under loaded conditions. The measurement procedure consists of inducinga static baseload with superimposed dynamic loads, which were controlled in magnitude and direction, at the tool centre point ofthe machine tool. The measurement procedure uses the Loaded Double Ball Bar and measures the dynamic displacement with threeNon-Contact Capacitive Probes. The measurement procedure is implemented in a case study on a 5-axis machining centre.Finally, the manuscript concludes with a discussion on the utility value of the translational dynamic stiffness matrix for the designand operation of machine tools as well as the possibility to expand the measurement procedure to capture the dynamic stiffnessusing quasi-static movements of the machine tool.

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  • 37.
    Theissen, Nikolas Alexander
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Laspas, Theodoros
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Archenti, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Closed-force-loop elastostatic calibration of serial articulated robots2019In: Robotics and Computer-Integrated Manufacturing, ISSN 0736-5845, E-ISSN 1879-2537, Vol. 57, p. 86-91Article in journal (Refereed)
    Abstract [en]

    This paper presents a novel methodology to measure the compliance of articulated serial robots based on the Elastically Linked Systems concept. The idea behind the methodology is to measure serial articulated robots with customized external wrench vectors under a closed-force-loop. The methodology proposes to measure robots in use-case defined configurations to increase the effect of the identified model parameters on their later implementation. The measurement methodology utilizes the Loaded Double Ball Bar to customize wrench vectors and a laser tracker to measure the system response. In particular, the Loaded Double Ball Bar creates the closed-force-loop to create a flow of forces similar to the intended application of the robot. The methodology is applied to an industrial robot with six rotary joints using the LDBB and a laser tracker. Finally, the paper ends on a discussion about the implementation of the model parameters to improve the accuracy of robots as well as challenges to realize a more cost efficient elastostatic calibration.

  • 38.
    Theissen, Nikolas Alexander
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Laspas, Theodoros
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Cedergren, Stefan
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems. GKN Aerospace Engine Systems, Research and Technology Centre.
    Archenti, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems. KTH, School of Industrial Engineering and Management (ITM), Sustainable production development, Processledning och hållbar produktion.
    Measurement for the identification of static and quasi-static rotational stiffness2021In: Precision engineering, ISSN 0141-6359, E-ISSN 1873-2372, Vol. 72, p. 215-223Article in journal (Refereed)
    Abstract [en]

    Machine tool calibration can be employed to optimise tool path trajectories through on- and off-line compensation of anticipated deflections, which result from a process plan, and to assess the machine tools capability to comply with the geometric dimensions and tolerances of a process plan.

    This work presents a measurement for the identification of static and quasi-static rotational stiffness of a rotational joint of 5-axis machining centres. This work shall serve as a basis towards the calibration of translational as well as rotational stiffness of 5-axis machining centres. The novelty of this work lies partly in the measurement procedure for the quasi-static rotational stiffness, which relies on multiple circular trajectories, as well as in the comparison of the static and quasi-static rotational stiffness of machine tools, which is usually identified using finite element approaches. The measurement procedure for the static rotational stiffness consists of inducing a static load directly, from an overhead factory crane, to a single rotational joint and measuring its deflection with both three LVDTsLinear Variable Differential Transformers (LVDTs) as well as three Non-Contact Capacitive Probes (NCCPs). While the measurement for the quasi-static rotational stiffness induces quasi-static loads indirectly from the Loaded Double Ball Bar, with different magnitudes and radii from the axis of rotation, between the tool centre point and the machine tool table. The quasi-static measurement procedure measures the deflection with both three LVDTs as well as three NCCPs while the spindle tracks circular trajectories inscribed by the movement of the rotary axis. The measurement procedures are implemented in two case studies on 5-axis machining centres with significantly different kinematic configurations to be able to highlight and discuss the limitations of the applicability of the method. The presented method works well for machining centres with symmetric and acceptably with asymmetric structures due to the corresponding symmetry of the deflection field.

    Finally, the manuscript concludes with a contextualisation of the introduced measurement procedure towards fully calibrated machine tool models, i.e. translation and rotation as well as static and dynamic, which together with customised post-processors and process models, might form the future basis of a stiffness volumetric compensation system.

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    Theissen, Laspas et al. 2021 - Measurement for the identification
  • 39.
    Theissen, Nikolas Alexander
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Laspas, Theodoros
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Szipka, Károly
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Archenti, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Sustainable production development, Processledning och hållbar produktion.
    Measurement and identification of translational stiffness matrix for static loads in machine tools2020In: Proceedings of the 20th International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2020, euspen , 2020, p. 497-498Conference paper (Refereed)
    Abstract [en]

    Stiffness is an important characteristic of production machinery, as it contributes to its ability to precisely maintain the pose between a tool centre point with respect to a workpiece under loads. For machine tools, it directly affects the geometric dimensions and surface properties of the parts, i.e. how closely the parts match their design drawings. This work presents an efficient measurement procedure to measure and identify the full translational stiffness matrices of machine tools. The measurement procedure consists of inducing static loads, which vary in magnitude and direction, at the tool centre point of the machine tool using the Loaded Double Ball Bar and measures the displacement with three Linear Variable Differential Transformers. The main components of the uncertainty budget related to the measurement of the cross compliance are also summarized. The measurement procedure is implemented in a case study on a 5-axis machining centre. Finally, the manuscript concludes with a discussion on the utility value of the translational stiffness matrix for the design and operation of machine tools as well as the possibility to expand the measurement procedure to capture the quasi-static and dynamic compliance.

  • 40.
    Theissen, Nikolas Alexander
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Laspas, Theodoros
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Szipka, Károly
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Sustainable Production Systems. KTH, School of Industrial Engineering and Management (ITM), Sustainable production development, Process Management and Sustainable Industry.
    Archenti, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Sustainable production development, Process Management and Sustainable Industry.
    Virtual machining system simulator: Analysis of machine tool accuracy2018In: Procedia Manufacturing, Elsevier B.V. , 2018, p. 338-343Conference paper (Refereed)
    Abstract [en]

    This paper presents a novel Virtual Machining System Simulator (VMSS) which quantifies and visualizes the effect of machine tool errors under quasi-static load conditions on the machine tool's accuracy. The VMSS is a generalized machine tool model that incorporates geometric errors and static loads to simulate the interaction between the machine tool structure and the cutting process. The errors are captured and described through the synthesis of bottom-up and top-down model building approaches. The paper presents ideas how to utilize the information from the VMSS to improve the process capability and discusses challenges to realise a fully digitized model. 

  • 41.
    Theissen, Nikolas Alexander
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Monetti, Fabio Marco
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Digital Smart Production.
    Gonzalez, Monica
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Maffei, Antonio
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Towards quasi-static kinematic calibration of serial articulated industrial manipulators2022In: MED 2022 30th Mediterranean Conference on Control and Automation, Institute of Electrical and Electronics Engineers (IEEE), 2022, p. 872-877Conference paper (Refereed)
    Abstract [en]

    Research on kinematic calibration of industrial robots has focused on applying different measurement instruments into open- and closed-loop approaches and optimising calibration configurations through various cost functions. Such ways are either expensive or time-consuming. This work presents essential steps towards realising quasi-static kinematic calibration of industrial manipulators. This approach employs measurement data from a quasi-static measurement instead of a static one to identify the model parameters and has the potential of considerably reducing the measurement phase time during calibration. The focus lies on the technological challenges needed to achieve a successful quasi-static kinematic calibration, such as the trajectory generation, the measurement instrument and the controller data synchronisation. A case study assess the data obtained from a quasi-static kinematic measurement with a robot/tracker configuration of 100 mm/s and 100 Hz. The average positioning accuracy is similar for the static and the quasi-static measurement. The time for the quasi-static trajectory is reduced to almost one-third of the static trajectory time without considering the setup time.

  • 42.
    Tomkowski, Robert
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Holmberg, Jonas (Contributor)
    RISE.
    Jonsson, Stefan (Contributor)
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Hammersberg, Peter (Contributor)
    Chalmers.
    Kristoffersen, Hans (Contributor)
    RISE.
    Nerman, Peter (Contributor)
    Scania CV AB.
    Olavison, Jari (Contributor)
    Volvo AB.
    Archenti, Andreas (Contributor)
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    The Barkhasuen Noise Measurements: Good Practice Guide2022 (ed. 2)Book (Refereed)
    Abstract [en]

    The KTH Royal Institute of Technology (Stockholm, Sweden) as a project leader allowed strengthening collaboration between academic and industrial experts in the field of non-destructive testing (NDT), machining and metrology. This scientific consortium had found an efficient way for scientific collaboration, in which we conducted many experiments, meetings, and talks on the project’s research subject. This book is a result of all the mentioned activities and more. Many experts from both sides actively participated in the creation of this guide and are listed in the list of contributors.

    The authors hope that after reading this guide, BN measurements can be carried out more systematically, with higher accuracy, traceability and lower uncertainty. The authors do not aim to replace a whole raft of good textbooks, operator’s manuals, specifications, and standards (if they exist); rather, they want to present an overview of good practices and techniques. These recommendations are also a result of many discussions conducted by the project team members during the project’s duration.

    The book is divided into two parts. The first part of the book, “Measurement Good Practice Guide”, presents a comprehensive overview of the Barkhausen noise (BN) measurement method used to describe and analyze different features of ferromagnetic materials, such as residual stress level, hardening depth, among others. The primary focus is on mechanical parts for the automotive industry, in particular, the camshaft and crankshaft. The good practice guide is intended for those who need to make BN measurements but are not necessarily trained to use this method or are still not comfortable about measurement itself. By reading this guide, one can gain basic knowledge regarding good practices for making magnetic measurements with the BN method. Based on a few principles and tips from good practices, the reader will be able to create a Standard Operating Procedure (SOP) for their purpose. SOPs for BN are presented in the appendices.

    The second part of the book “Qualification and Certification of Personnel” presents requirements of the personal certification for Barkhausen testing and is aligned with applicable standards. The authors recommend performing internal and external certification of personnel to do achieve more conscious and reliable measurements.

    This book has been prepared by the scientific consortium under the research project FFI OFP4p – Non-Destructive Characterization Concepts for Production, 2015–2018 co-founded in 50% by VINNOVA, Sweden’s innovation agency. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights.

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    BNT_GPG
  • 43.
    Troll, Peter
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Szipka, Károly
    KTH, School of Industrial Engineering and Management (ITM), Sustainable production development, Processledning och hållbar produktion.
    Archenti, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Sustainable production development, Processledning och hållbar produktion.
    Indoor Localization of Quadcopters in Industrial Environment2020In: Advances in Transdisciplinary Engineering, IOS Press , 2020, p. 453-464Conference paper (Refereed)
    Abstract [en]

    The research work in this paper was carried out to reach advanced positioning capabilities of unmanned aerial vehicles (UAVs) for indoor applications. The paper includes the design of a quadcopter and the implementation of a control system with the capability to position the quadcopter indoor using onboard visual pose estimation system, without the help of GPS. The project also covered the design and implementation of quadcopter hardware and the control software. The developed hardware enables the quadcopter to raise at least 0.5kg additional payload. The system was developed on a Raspberry single-board computer in combination with a PixHawk flight controller. OpenCV library was used to implement the necessary computer vision. The Open-source software-based solution was developed in the Robotic Operating System (ROS) environment, which performs sensor reading and communication with the flight controller while recording data about its operation and transmits those to the user interface. For the vision-based position estimation, pre-positioned printed markers were used. The markers were generated by ArUco coding, which exactly defines the current position and orientation of the quadcopter, with the help of computer vision. The resulting data was processed in the ROS environment. LiDAR with Hector SLAM algorithm was used to map the objects around the quadcopter. The project also deals with the necessary camera calibration. The fusion of signals from the camera and from the IMU (Inertial Measurement Unit) was achieved by using Extended Kalman Filter (EKF). The evaluation of the completed positioning system was performed with an OptiTrack optical-based external multi-camera measurement system. The introduced evaluation method has enough precision to be used to investigate the enhancement of positioning performance of quadcopters, as well as fine-Tuning the parameters of the used controller and filtering approach. The payload capacity allows autonomous material handling indoors. Based on the experiments, the system has an accurate positioning system to be suitable for industrial application.

  • 44.
    Vaddadi, Bhavana
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Centres, Integrated Transport Research Lab, ITRL.
    Zhao, Xiaoyu
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Susilo, Yusak
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, System Analysis and Economics. KTH, School of Industrial Engineering and Management (ITM), Centres, Integrated Transport Research Lab, ITRL.
    Nybacka, Mikael
    KTH, School of Industrial Engineering and Management (ITM), Centres, Integrated Transport Research Lab, ITRL.
    Pernestål Brenden, Anna
    KTH, School of Industrial Engineering and Management (ITM), Centres, Integrated Transport Research Lab, ITRL.
    Measuring system level effects of Corporate MaaS: A case study in Sweden2019In: Towards human scale cities -open and happy, 2019, p. 68-Conference paper (Other academic)
    Abstract [en]

    Mobility as a Service (MaaS) integrates different elements of transportation, which mainly are: ticket & payment integration, mobility modes integration and ICT integration. It plays an important role as it is expected to enable the shift from private car use to shared and sustainable transport modes. 

    Corporate Mobility as a Service (CMaaS) is a version of MaaS, which enables mobility within as well as to and from, a work site for the employees. CMaaS fulfils all the above-mentioned characteristics of MaaS. It may also consist of different service packages which could either be free and/ or paid. 

    CMaaS is a new concept and its implementation is limited. The expected benefits of CMaaS are both to support a shift toward sustainable transportation and to be the first step towards more general MaaS solutions. In this paper, we study the effects of CMaaS from economic, environmental and societal aspects on individual, organizational and social levels. 

    The case study of the implementation of CMaaS at a company with 13000 employees located in a city 30 km outside of Stockholm, Sweden, is used in this study. The estate spans over three-square kilometres, and the facilities are spread over the area with distances between the buildings of up to 5kms. 

    The service provides internal taxis, small shuttle buses and e-bikes to aid the employees to get around the estate during the working day. It also offers a commuter bus service to and from Stockholm City. The evaluation is based on data collected through three surveys with more than 400 respondents, complemented with operational data. 

    The analysis is ongoing and will be completed during the spring. Preliminary results show that CMaaS have supported the shift towards the use of e-bikes in favour of motorized modes which has positive effects on e.g. health and emissions. 

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  • 45. Villamil Velasquez, C.
    et al.
    Salehi, Niloufar
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Hallstedt, S. I.
    HOW CAN INFORMATION and COMMUNICATIONS TECHNOLOGY SUPPORT the LINK between CIRCULAR ECONOMY and PRODUCT LIFE CYCLE MANAGEMENT?: - A REVIEW2020In: Proceedings of the Design Society: DESIGN Conference, Cambridge University Press (CUP) , 2020, p. 2187-2196Conference paper (Refereed)
    Abstract [en]

    Linear production is related to resource scarcity and negative environmental impacts. Circular Economy (CE) emerged for society transition towards sustainability, based on regenerative systems and multiple life cycle products. Product Life cycle Management (PLM) supports the whole life cycle with the aid of Information and Communication Technology (ICT). A literature review analyzed the role of ICT enabling CE based on PLM, identifying challenges and opportunities, active and passive PLM, system perspective, stakeholder's role, and sustainability. Concluding that ICT enables the CE transition.

  • 46.
    Wang, Yong
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Process. Wuhan Univ Technol, Wuhan, Hubei, Peoples R China.;Hubei Business Serv Dev Res Ctr, Wuhan, Hubei, Peoples R China..
    Zhang, Pei-Lin
    Wuhan Univ Technol, Wuhan, Hubei, Peoples R China..
    Semere, Daniel
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Nicolescu, Mihai
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Zhang, Qing-Ying
    Wuhan Univ Technol, Wuhan, Hubei, Peoples R China..
    Research on Development Mechanism of "Family Farm" under E-commerce2018In: 2018 International Conference On E-Commerce And Contemporary Economic Development (ECED 2018), DEStech Publications , 2018, p. 1-12Conference paper (Refereed)
    Abstract [en]

    Agricultural e-commerce will be the production and processing of agricultural products, organic combination of transportation storage and distribution sales process, the omni-directional into e-commerce system, through the computer information network, and with their own production base and advanced logistics distribution system as the backing, the convenience of using the Internet, to complete the purchase of agricultural products, sales, online payment and other related business process. Developing agricultural e-commerce is conducive to promoting agricultural development and farmers' income, and the "family farm", as a large-scale, intensive, the commercialization of agricultural management system, complied with the trend of the development of electronic commerce, so as to speed up the development of e-commerce, highlight the function mechanism of "family farm" in the agricultural e-commerce mechanism.

  • 47.
    Wolf, Adam
    et al.
    Baxalta Innovat GmbH, A-1221 Vienna, Austria.;Obuda Univ, Doctoral Sch Appl Informat & Appl Math, H-1034 Budapest, Hungary.;Obuda Univ, Antal Bejczy Ctr Intelligent Robot, H-1034 Budapest, Hungary..
    Troll, Peter
    KTH, School of Industrial Engineering and Management (ITM), Sustainable production development.
    Romeder-Finger, Stefan
    Baxalta Innovat GmbH, A-1221 Vienna, Austria..
    Archenti, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Sustainable production development. KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Szell, Karoly
    Obuda Univ, Doctoral Sch Appl Informat & Appl Math, H-1034 Budapest, Hungary.;Obuda Univ, Antal Bejczy Ctr Intelligent Robot, H-1034 Budapest, Hungary.;Obuda Univ, Alba Regia Tech Fac, H-8000 Szekesfehervar, Hungary..
    Galambos, Peter
    Obuda Univ, Doctoral Sch Appl Informat & Appl Math, H-1034 Budapest, Hungary.;Obuda Univ, Antal Bejczy Ctr Intelligent Robot, H-1034 Budapest, Hungary..
    A Benchmark of Popular Indoor 3D Reconstruction Technologies: Comparison of ARCore and RTAB-Map2020In: Electronics, E-ISSN 2079-9292, Vol. 9, no 12, article id 2091Article in journal (Refereed)
    Abstract [en]

    The fast evolution in computational and sensor technologies brings previously niche solutions to a wider userbase. As such, 3D reconstruction technologies are reaching new use-cases in scientific and everyday areas where they were not present before. Cost-effective and easy-to-use solutions include camera-based 3D scanning techniques, such as photogrammetry. This paper provides an overview of the available solutions and discusses in detail the depth-image based Real-time Appearance-based Mapping (RTAB-Map) technique as well as a smartphone-based solution that utilises ARCore, the Augmented Reality (AR) framework of Google. To qualitatively compare the two 3D reconstruction technologies, a simple length measurement-based method was applied with a purpose-designed reference object. The captured data were then analysed by a processing algorithm. In addition to the experimental results, specific case studies are briefly discussed, evaluating the applicability based on the capabilities of the technologies. As such, the paper presents the use-case of interior surveying in an automated laboratory as well as an example for using the discussed techniques for landmark surveying. The major findings are that point clouds created with these technologies provide a direction- and shape-accurate model, but those contain mesh continuity errors, and the estimated scale factor has a large standard deviation.

  • 48.
    Yacob, Filmon
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Part Quality Prediction and Variation Reduction in Multistage Machining Processes Based on Skin Model Shapes2020Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    All manufacturing processes inevitably induce variations into manufactured parts that may result in nonconformance. Nonconforming parts incur costs due to the additional process required for rework or scrap loss. Hence, methodical efforts to reduce these variations are necessary for competitive manufacturing. To achieve this, effective variation reduction strategies have to be in place. In a multistage machining context, this could mean robust, rapid, and accurate approaches for representation and prediction of variations, change detection, variations source identification, and compensation.

    Moreover, the approaches used should be capable of handling all forms of errors contributing to the propagation of variations and nonconformance. Existing part variation and variation propagation analysis methods for multistage machining are limited to orientation and position errors, neglecting form errors. Form errors can be captured by utilizing the concept of Skin Models Shapes (SMSs). The application of SMSs for multistage machining and variation reduction strategies has been limited and not established yet. This thesis contributes to developing and demonstrating the use of SMSs for part quality prediction and variation reduction in multistage machining processes.

    The specific contribution of the thesis can be summarized as (i) the derivations of variation propagation models using dual quaternions; (ii) part quality prediction considering fixtures with locating surfaces, 3-2-1, and N-2-1 (N>3) locators; (iii) Octrees based method for performing statistical shape analysis; (iv) change and anomaly detection using machine learning classifiers; (v) variation source identification using pattern matching technique; (vi) and estimation of variation compensation values using dual quaternions.

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  • 49.
    Yacob, Filmon
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems. KTH.
    Semere, Daniel
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    A multilayer shallow learning approach to variation prediction and variation source identification in multistage machining processes2020In: Journal of Intelligent Manufacturing, ISSN 0956-5515, E-ISSN 1572-8145Article in journal (Refereed)
    Abstract [en]

    Variation propagation modelling in multistage machining processes through use of analytical approaches has been widely investigated for the purposes of dimension prediction and variation source identification. Yet the variation prediction of complex features is non-trivial task tomodel mathematically.Moreover, the application ofthevariation propagation approaches and associated variation source identification techniques using SkinModel Shapes is unclear. This paper proposes amultilayer shallow neural network regression approach to predict geometrical deviations of parts given manufacturing errors. The neural network is trained on a simulated data, generated from machining simulation of a point cloud of a part. Further, given a point cloud data of a machined feature, the source of variation can be identified by optimally matching the deviation patterns of the actual surface with that of shallow neural network generated surface. To demonstrate the method, a two-stage machining process and a virtual part that has planar, cylindrical and torus features was considered. The geometric characteristics of machined features and the sources variation could be predicted at an error of 1% and 4.25%, respectively. This work extends the application of Skin Model Shapes in variation propagation analysis in multistage manufacturing.

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  • 50.
    Yacob, Filmon
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Manufacturing and Metrology Systems.
    Semere, Daniel
    KTH.
    Part quality prediction in multistage machining processes with fixtures based on locating surfaces using dual quaternions2021Other (Other academic)
    Abstract [en]

    The mathematical modelling of variation propagation in multistage machining processes helps to perform a quick analysis and diagnosis of the processes. The models for part quality prediction, such as Stream of Variation, include homogeneous transformations of the vectorial representations of parts and fixtures. However, these prediction models are complex when considering fixtures with locating surfaces and the associated matrix size is large. Towards mitigating the mathematical complexity, dual quaternions are proposed in representing and transforming a virtual part and fixture. To achieve this, the primary feature datum is assembled to the primary locating surface, followed by sliding the part to secondary and tertiary locating surfaces by reducing the distance between the vertices of the part and the locating surface. The prediction following the proposed approach gave a result within 0.36 % of the prediction made using CAD/CAM models and maintained the largest matrix size of 9 by 8 for a part with 9 features.

12 1 - 50 of 65
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