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  • 1.
    Ahmadzadeh, Farzaneh
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Innovation and Product Realisation.
    Bengtsson, Marcus
    Mälardalen University, School of Innovation, Design and Engineering, Innovation and Product Realisation.
    Using evidential reasoning approach for prioritization of maintenance-related waste caused by human factors-a case study2017In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 90, no 9-12, p. 2761-2775Article in journal (Refereed)
    Abstract [en]

    The reduction and elimination of maintenance-related waste is receiving increasing attention because of the negative effect of such waste on production costs. The overall goal of this research is to identify and prioritize factors that can be considered maintenance-related waste within the automotive manufacturing industry. Five manufacturing companies participated in a workshop to identify root causes of maintenance-related waste; 16 categories were found. The identified factors were heavily reliant on human factors as a root or major contributory cause at different levels affecting performance and productivity. For prioritization, the evidential reasoning (ER) approach which is one of the latest developments in multi-criteria decision-making is applied. A basic tree structure necessary for ER assessment is developed based on the workshop results as well as literature on human factors. Then, a survey on basic attributes at the lowest level of this tree is designed and performed at one of the companies participating in the workshop. The application of ER shows that, on an overall level, "management condition" is in first order and "maintainer condition" and "working condition" are in second and third order respectively as the worst cases for creating maintenance-related waste. On the most delimited level "inadequate resources" and "weather/indoor climate" have the highest and lowest average scores respectively in ER ranking or prioritization. This methodology with its resulting ranking can be used as a tool to create awareness for managers seeking to reduce or eliminate maintenance-related waste.

  • 2.
    Ahmadzadeh, Farzaneh
    et al.
    Luleå University of Technology, Luleå, Sweden.
    Lundberg, Jan
    Luleå University of Technology, Luleå, Sweden.
    Strömberg, Thomas
    Luleå University of Technology, Luleå, Sweden.
    Multivariate process parameter change identification by neural network2013In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 69, no 9-12, p. 2261-2268Article in journal (Refereed)
    Abstract [en]

    Whenever there is an out-of-control signal in process parameter control charts, maintenance engineers try to diagnose the cause near the time of the signal which does not always lead to prompt identification of the source(s) of the out-of-control condition, and this in some cases yields to extremely high monetary loses for the manufacturer owner. This paper applies multivariate exponentially weighted moving average (MEWMA) control charts and neural networks to make the signal identification more effective. The simulation of this procedure shows that this new control chart can be very effective in detecting the actual change point for all process dimension and all shift magnitudes considered. This methodology can be used in manufacturing and process industries to predict change points and expedite the search for failure causing parameters, resulting in improved quality at reduced overall cost. This research shows development of MEWMA by usage of neural network for identifying the step change-point and the variable responsible for the change in the process mean vector.

  • 3.
    Ahmadzadeh, Farzaneh
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Lundberg, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Strömberg, Thomas
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Multivariate process parameter change identification by neural network2013In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 69, no 9-12, p. 2261-2268Article in journal (Refereed)
    Abstract [en]

    Whenever there is an out-of-control signal in process parameter control charts, maintenance engineers try to diagnose the cause near the time of the signal which is not always lead to prompt identification of the source(s) of the out-of-control condition and this in some cases yields to extremely high monetary loses for manufacture owner. This paper applies multivariate exponentially weighted moving average (MEWMA) control charts and neural networks to make the signal identification more effective. The simulation of this procedure shows that this new control chart can be very effective in detecting the actual change point for all process dimension and all shift magnitudes considered. This methodology can be used in manufacturing and process industries to predict change points and expedite the search for failure causing parameters, resulting in improved quality at reduced overall cost. This research shows development of MEWMA by usage of neural network for identifying the step change point and the variable responsible for the change in the process mean vector.

  • 4.
    Amouzgar, Kaveh
    et al.
    University of Skövde, School of Engineering Science.
    Bandaru, Sunith
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Andersson, Tobias J.
    University of Skövde, The Virtual Systems Research Centre.
    Ng, Amos H. C.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    A framework for simulation based multi-objective optimization and knowledge discovery of machining process2018In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015Article in journal (Refereed)
  • 5.
    Asala, G.
    et al.
    University of Manitoba, Winnipeg, R3T 5V6, Canada .
    Andersson, Joel
    University West, Department of Engineering Science, Division of Mechanical Engineering.
    Ojo, Olanrewaj A.
    University of Manitoba, Winnipeg, R3T 5V6, Canada .
    Precipitation behavior of gamma′ precipitates in the fusion zone of TIG welded ATI 718Plus®2016In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 87, no 9-12, p. 2721-2729Article in journal (Refereed)
    Abstract [en]

    The precipitation behavior of the main strengthening phase, γ′ precipitates, in ATI 718Plus® superalloy after Tungsten Inert Gas (TIG) welding and postweld heat treatments has been studied. In contrast to electron beam welding, where no γ′ precipitates are reported to form in the as-welded condition, analytical transmission electron microscopy study in this work revealed the formation of γ′ precipitates after the TIG welding, albeit in a non-uniform distribution manner. This is attributable to a more extensive elemental microsegregation that occurred into the interdendritic liquid and slower cooling rate during the TIG welding, which also induced the formation of interdendritic Nb-rich Laves phase particles and MC-type carbides. Theoretical calculations were performed to study the influence of Nb microsegregation, on both the kinetics and extent of γ′ precipitation, and the results agree with experimental observations. It is found that the precipitation kinetics, and not the extent of γ′ precipitate formation in the fusion zone, during postweld heat treatments is affected by the micro-segregation of Nb that produced Laves phase particles during the weld solidification.

  • 6. Ashokkumar, Thanganadar
    et al.
    Rajadurai, Arunachalam
    Gouthama,
    Hussami, Linda L.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    A study of densification and on factors affecting the density of Ni (x)-Fe100-x nanopowders prepared by mechanical alloying and sintered by spark plasma2013In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 65, no 9-12, p. 1201-1213Article in journal (Refereed)
    Abstract [en]

    Mechanical alloying through high-energy ball milling was used in the production of Ni-Fe alloy powders from elemental Ni and Fe powders of average particle size 80 and 25 mu m, respectively. High-energy planetary ball milling at room temperature was performed for various time durations ranging between 2 and 100 h. SPS apparatus was used for sintering of powder particles. Density of all specimens was reported and a maximum densification of 99 % was achieved in 50 wt.% Ni-Fe milled for 16 h prior to spark plasma sintering at 1,223 K.

  • 7.
    Berglund, Johan
    et al.
    Sandvik Tooling, R & D Center Olofström, Sweden.
    Liljengren, Magnus
    Olofström School of Automotive Stamping, Olofström, Sweden.
    Rosén, Bengt-Göran
    Halmstad University, School of Business and Engineering (SET), Mechanical Engineering and Industrial Design (MTEK).
    On finishing of pressing die surfaces using machine hammer peening2011In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 52, no 1-4, p. 115-121Article in journal (Refereed)
    Abstract [en]

    Machine hammer peening (MHP) is a new method for finishing of surfaces. With this method, the workpiece surface is hammered with a spherical carbide tool. The main objective of the study was to evaluate whether the MHP method could become a plausible substitute for manual polishing in pressing die manufacturing where nodular cast iron is a common workpiece material. To do this, sample nodular cast iron surfaces were hammered and evaluated. Changes to the surfaces were evaluated using surface roughness measurements, hardness measurements and optical images. First of all, the workpiece surface was smoothened. Secondly, the surface hardness was increased significantly. Thirdly, the nodules on the workpiece surface were affected. They appeared to be smaller and not as visible. This effect would likely create a die surface less prone to galling since the cavities would not be filled with sheet metal to the same extent in a forming operation. In addition, with MHP, the amount of polishing needed to manufacture a die surface can be reduced because of the smoothening effect.

  • 8.
    Bergström, Per
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Edlund, Ove
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Söderkvist, Inge
    Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    Repeated surface registration for on-line use2011In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 54, no 5-8, p. 677-689Article in journal (Refereed)
    Abstract [en]

    We consider the problem of matching sets of 3D points from a measured surface to the surface of a corresponding computer-aided design (CAD) object. The problem arises in the production line where the shape of the produced items is to be compared on-line with its pre-described shape. The involved registration problem is solved using the iterative closest point (ICP) method. In order to make it suitable for on-line use, i.e., make it fast, we pre-process the surface representation of the CAD object. A data structure for this purpose is proposed and named Distance Varying Grid tree. It is based on a regular grid that encloses points sampled from the CAD surfaces. Additional finer grids are added to the vertices in the grid that are close to the sampled points. The structure is efficient since it utilizes that the sampled points are distributed on surfaces, and it provides fast identification of the sampled point that is closest to a measured point. A local linear approximation of the surface is used for improving the accuracy. Experiments are done on items produced for the body of a car. The experiments show that it is possible to reach good accuracy in the registration and decreasing the computational time by a factor 700 compared with using the common kd-tree structure.

  • 9.
    Bunaziv, Ivan
    et al.
    Department of Mechanical and Industrial Engineering, Norwegian University of Science and Technology, Trondheim.
    Frostevarg, Jan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Product and Production Development.
    Akselsen, Odd M.
    Department of Mechanical and Industrial Engineering, Norwegian University of Science and Technology, Trondheim.
    Kaplan, Alexander
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Product and Production Development.
    The penetration efficiency of thick plate laser-arc hybrid welding2018In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015Article in journal (Refereed)
    Abstract [en]

    Double-sided fiber laser-arc hybrid welding was used to join 45 mm thick high strength steel over a wide range of parameters in order to investigate the efficiency of the process. Air gap size, I- and Y-groove type preparation, pulsed and cold metal transfer pulsed arc modes, arc-laser setup, and travel speeds were compared, and in all cases, sufficient filler material was provided to fully fill the gap. The welds were investigated using high speed imaging and cross-sectional analysis to identify penetration depths, morphology, and imperfections. Larger joint air gaps were found to contribute most to weld penetration depth. Surprisingly, increased line energy decreased penetration efficiency in most cases. The laser-arc interdistance was also investigated, revealing an arc size and melt flow dependency for achieving higher penetration depth for a leading arc. It was found that, although penetration can be optimized, solidification cracking can be a limiting factor in the application of deep penetration hybrid welding for thick steel section joining.

  • 10.
    Campos, Jaime
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Mathematics and Systems Engineering.
    Jantunen, Jantunen
    Prakash, Om
    Växjö University.
    A web and mobile device architecture for mobile e-maintenance2009In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 45, no 1-2, p. 71-80Article in journal (Refereed)
    Abstract [en]

    The paper presents the development of a mobile maintenance support system based on web and mobile device technologies, i.e., personal digital assistant. The architecture relies on a shop floor system and a supporting system in a diagnostic center. The shop floor system is supported by a mobile device, which helps the maintenance engineer to perform maintenance tasks. This gives great support to the maintenance engineer as it facilitates the access to decision-making support, work order, and spare part handling modules etc. that are available in the device. The diagnostic center provides the maintenance engineer with decision support for his various tasks, when needed. Moreover, a database table listener agent, located at the database server, was developed to keep track of the maintenance engineer’s work orders at a certain priority level. The proposed approach can reduce the maintenance costs and solve the problem of the unavailability of an expert. More efficient maintenance is believed to be achieved through the use of web and agent technologies since data, maintenance systems, and processing can be gathered and integrated and data can be acquired from additional sources when necessary. The proposed system, the web, and embedded technologies as well as remote communication were tested successfully.

  • 11.
    Cedergren, Stefan
    et al.
    Department of Materials and Manufacturing Technology, Chalmers University of Technology, 41296, Gothenburg, Sweden, Research and Technology Centre, GKN Aerospace Engine Systems, 46181, Trollhättan, Sweden.
    Frangoudis, Costantinos
    KTH, School of Industrial Engineering and Management (ITM).
    Archenti, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Pederson, Robert
    Research and Technology Centre, GKN Aerospace Engine Systems, 46181, Trollhättan, Sweden.
    Sjöberg, Göran
    Research and Technology Centre, GKN Aerospace Engine Systems, 46181, Trollhättan, Sweden.
    Influence of work material microstructure on vibrations when machining cast Ti-6Al-4V2015In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, p. 1-15Article in journal (Refereed)
    Abstract [en]

    Titanium alloys are known to produce shear-localized chips during machining, resulting in cyclic variations in cutting forces which in turn could cause severe problems with vibrations. However, at low cutting speeds and feed rates, continuous chips are formed, with an increase in both parameters favoring the transition to shear-localized chips. This transition is affected by work material microstructure, where a coarse microstructure gives anisotropic effects, e.g., when the size of alpha colonies is on the same order of magnitude as the primary cutting zone. The change in chip morphology with an increase in cutting parameters will then be dependent on the orientation of alpha colonies within the cutting zone. The microstructure of work material can show large variations depending on product form, e.g., cast, wrought, or sheet material, thus affecting whether the chip formation is isotropic or anisotropic. Other sources of variations also exist that can be found within the same component, such as segregation of alloying elements and differences in thermo-mechanical history during processing due to geometry. In this study, the interaction between work material microstructure, process parameters, and the machining system’s structural characteristics is studied. The aim is to further increase the knowledge about vibrations during machining of titanium and the role of microstructure and machining system properties. Different microstructures were produced by adding boron to cast Ti-6Al-4V material, where the resulting colony sizes gave both isotropic and anisotropic chip formation within the chosen cutting data range. The machining systems dynamic properties were varied by using different tool overhangs, thereby simulating different configurations of natural frequencies and stiffness. The results show the influence of both microstructure and machining system’s structural characteristics on the dynamic response of the system for different process parameters. This information can be used to increase robustness of machining operations taking into consideration this three-way relationship.

  • 12.
    Chronakis, Ioannis
    et al.
    RISE, Swerea, Swerea IVF.
    Mekras, N.D.
    ANTER Ltd..
    Wiesauer, K.
    Upper Austrian Research GmbH.
    Breuer, E.
    Upper Austrian Research GmbH.
    Stifter, D.
    Upper Austrian Research GmbH.
    Fuentes, G.F.
    AIN.
    Qin, Y.
    University of Strathclyde.
    MASMICRO micro-/nano-materials processing, analysis, inspection and materials knowledge management2010In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 47, p. 963-971Article in journal (Refereed)
    Abstract [en]

    The main goals of the 'Material Innovation and Testing' within MASMICRO are the identification of the miniature/micro-materials which are formable, development of new materials for forming and machining, development of an integrated material-testing system and study of material properties for design/analysis applications. Examples of collaborative work and results are presented regarding the processing of functional electrospun polymer micro-/nano-fibre structures and the characterization of their interface properties with tribological testing. By means of optical coherence tomography, a non-destructive inspection approach for these micro-/nano-structured webs was developed and it is also documented in the paper. Further, an application example of artificial neural networks (ANNs) is given, concerning the modelling of nano-fibres material behaviour under tensile testing. It is shown how artificial intelligence approaches (knowledge-based systems-KBS and ANNs) can support, significantly, the representation and processing of materials' knowledge of both, symbolic type, in the case of KBS, and algorithmic type, in the case of ANNs, for the cases dealt within the MASMICRO. © Springer-Verlag London Limited 2009.

  • 13.
    De Backer, Jeroen
    et al.
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Bolmsjö, Gunnar
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Christiansson, Anna-Karin
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Temperature control of robotic friction stir welding using the thermoelectric effect2014In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 70, no 1-4, p. 375-383Article in journal (Refereed)
    Abstract [en]

    Friction stir welding (FSW) of non-linear joints receives an increasing interest from several industrial sectors like automotive, urban transport and aerospace. A force-controlled robot is particularly suitable for welding complex geometries in lightweight alloys. However, complex geometries including three-dimensional joints, non-constant thicknesses and heat sinks such as clamps cause varying heat dissipation in the welded product. This will lead to changes in the process temperature and hence an unstable FSW process with varying mechanical properties. Furthermore, overheating can lead to a meltdown, causing the tool to sink down into the workpiece. This paper describes a temperature controller that modifies the spindle speed to maintain a constant welding temperature. A newly developed temperature measurement method is used which is able to measure the average tool temperature without the need for thermocouples inside the tool. The method is used to control both the plunging and welding operation. The developments presented here are applied to a robotic FSW system and can be directly implemented in a production setting.

  • 14.
    De Vin, Leo
    et al.
    University of Skövde, School of Technology and Society.
    Ng, Amos H. C.
    University of Skövde, School of Technology and Society.
    Sundberg, Martin
    University of Skövde, School of Technology and Society.
    Moore, Philip R.
    De Montfort Univ, Mechatron Res Ctr, Leicester LE1 9BH, Leics, England.
    Pu, Junsheng
    De Montfort Univ, Mechatron Res Ctr, Leicester LE1 9BH, Leics, England.
    Wong, Bill C.-B.
    De Montfort Univ, Mechatron Res Ctr, Leicester LE1 9BH, Leics, England.
    Information fusion for decision support in manufacturing: studies from the defense sector2008In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 35, no 9-10, p. 908-915Article in journal (Other academic)
    Abstract [en]

    Information fusion, the synergistic combination of information from multiple sources, is an established research area within the defense sector. In manufacturing however, it is less well-established, with the exception of sensor/data fusion for automatic decision making. The paper briefly discusses some military specific models and methods for information fusion; analogies with manufacturing as well as a more generalized terminology are presented. “Manufacturing” is an application scenario within a Swedish information fusion research program that studies information fusion from databases, sensors and simulations with (currently) a focus on support for human decision making. An area of particular interest is that of advanced applications of virtual manufacturing such as synthetic environments, a form of hardware in the loop simulation that can deliver services such as service and maintenance at remote locations. In this area, the manufacturing industry can benefit from ongoing work in the defense sector related to verification, validation and accreditation of simulation models.

  • 15.
    Englund, Cristofer
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent systems (IS-lab).
    Verikas, Antanas
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent systems (IS-lab).
    Ink feed control in a web-fed offset printing press2008In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 39, no 9-10, p. 919-930Article in journal (Refereed)
    Abstract [en]

    Automatic and robust ink feed control in a web- fed offset printing press is the objective of this work. To achieve this goal an integrating controller and a multiple neural models-based controller are combined. The neural networks-based printing process models are built and updated automatically without any interaction from the user. The multiple models-based controller is superior to the integrating controller as the process is running in the training region of the models. However, the multiple models-based controller may run into generalisation prob- lems if the process starts operating in a new part of the input space. Such situations are automatically detected and the integrating controller temporary takes over the process control. The developed control configuration has success- fully been used to automatically control the ink feed in the web-fed offset printing press according to the target amount of ink. Use of the developed tools led to higher print quality and lower ink and paper waste.

  • 16.
    Ericson Öberg, Anna
    et al.
    Chalmers, Gothenburg, Sweden.
    Åstrand, Erik
    University West, Department of Engineering Science, Research Enviroment Production Technology West. Volvo Construct Equipment, Braås, Sweden.
    Improved productivity by reduced variation in gas metal arc welding (GMAW)2017In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 92, no 1-4, p. 1027-1038Article in journal (Refereed)
    Abstract [en]

    The purpose of the research conducted is to describe the consequences of variation in the welding industry and the effect it has on manufacturing productivity. The potential has shown to be hidden in unnecessarily stringent requirements and over-processing. This has been studied in steps: customer requirements, design and analysis, preparation, welding, and assessment. The effect of variation in each step has been analyzed including estimations of its productivity improvement potential. Theoretically, in a perfect situation, with customized requirements and eliminated variation, more than half of all welding could be removed. Such a reduction is certainly neither practical nor possible. However, a sensible, controlled reduction could still have a very high impact. The financial implications are therefore substantial. The improved productivity of the manufacturing resources could be used for business development and increased production. To be able to realize the potential, interdisciplinary efforts are necessary. Management across different functions need to agree on the intended product life and make decisions thereafter.

  • 17. Feng, Hsi-Yung
    et al.
    Han, Zhengyu
    Banerjee, Avisekh
    Wang, Lihui
    University of Skövde.
    A Composite Fitting Model of Discrete Handbook Data for Peripheral End Milling2009In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 44, no 5-6, p. 437-446Article in journal (Refereed)
    Abstract [en]

    Machining data handbooks are important reference books in the machining industry, as they provide recommended process parameter values for common machining operations. The machining data, although covering a wide range of relevant cutting conditions, are only listed under discrete cutting conditions. Rough interpolation-based calculations are often needed in order to estimate the process parameter values at the desired cutting condition. In this work, a compositefitting model is presented to fit a composite functional curve through the discrete handbook data of recommended cutting speeds and feeds with respect to the cutting condition of radial depth of cut for peripheral end milling. The objective is to establish a functional relationship from the handbook data such that recommended cutting speed and feed can be obtained for any given radial depth of cut. According to the tabulated layout of the machining data, the entire range of the radial depth of cut is divided into three segments having distinctive formulations and trends. Constraints are then imposed to preserve the trends and smoothly connect the adjacent segments. As a possible application of the presented model, a case study of machining a rectangular pocket is provided. Machining time of a potential process plan is readily evaluated based on the cutting speeds and feeds obtained from the composite model.

  • 18.
    Feng, Lei
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).
    Cai, Kai
    Wonham, W. M.
    A structural approach to the non-blocking supervisory control of discrete-event systems2009In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 41, no 11-12, p. 1152-1168Article in journal (Refereed)
    Abstract [en]

    Many practical and important systemic properties of manufacturing systems, like deadlock freeness, liveness, and reversibility, can be formulated as the non-blocking property of discrete-event systems. It can be difficult, however, to verify non-blocking or design a supervisor to guarantee non-blocking control because of state size explosion in the concurrency model. In this paper, we present sufficient conditions for the computation of (small) model abstractions that preserve the non-blocking property. As a consequence, hierarchical and decentralized control structures can be flexibly integrated, and the proposed approach can synthesize maximally permissive and non-blocking control with reduced computational effort. The solution is a group of decentralized supervisors that transparently displays control logic and admits relatively simple implementation.

  • 19.
    Frangoudis, Constantinos
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Rashid, Amir
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Nicolescu, Cornel Mihai
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Development and analysis of a consciously designed Joint Interface Module for improvement of a machining system's dynamic performance2017In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 88, no 1-4, p. 507-518Article in journal (Refereed)
    Abstract [en]

    Machining vibrations and dynamic instability of machine tools is an important consideration in machining systems. Common approaches for improving their dynamic performance target either the process, or intelligent, yet complex control systems with actuators. Given that machine tools' dynamic characteristics are largely defined by the characteristics of the joints, this article proposes a novel concept, attempting to create a new paradigm for improving the dynamic behaviour of machine tools-introducing modular machine tools components (Joint Interface Modules-JIMs) with joints deliberately designed for increasing dynamic stiffness and enhancing damping with the use of viscoelastic materials. Through a systematic model-based design process, a prototype replicating a reference tool holder was constructed exploiting viscoelastic materials and the dynamic response of the machining system was improved as a result of its introduction; in machining experiments, the stability limit was increased from around 2 mm depth of cut to 4 mm depth of cut, without compromising the rigidity of the system or changing the process parameters. The article also includes the results of investigations regarding the introduction of such prototypes in a machine tool and discusses the shortcomings of the stability lobe diagrams as a method for evaluating the performance of machine tool components with viscoelastically treated joints.

  • 20.
    FU, Qilin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Machine and Process Technology.
    Rashid, Amir
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Machine and Process Technology.
    Constraining the shear strain in viscoelastic materials and utlization of the “incompressible” properties for damping treatment in hybrid joint interface module to improve their effect for vibration control in machining2016In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 83, no 5, p. 1079-1097Article in journal (Refereed)
    Abstract [en]

    A hybrid joint interface module (HJIM) was developed using viscoelastic materials’ (VEM) “incompressible” property. The HJIM composes VEM layers compressed by screws. Its static stiffness and damping had been characterized by inverse receptance method. The analysis result showed that its static stiffness increases by nearly 50 % with increasing compression preload without compromising its loss factor. A comparison study of HJIM with a viscoelastic material joint interface module (VJIM) revealed that the change of the screws mechanical contact conditions affected the HJIM’s stiffness. Compression preload by fastening the screws, however, did not significantly affect the damping property of the HJIM. On the contrary to shear pre-strain, compression preload did not affect the VEM’s properties shown by studying the VJIM case. A workpiece was studied while fixed on the HJIM. Varying compression preload affected the stiffness of HJIM and that resulted in increased shear strain in VEM for certain modes while decreased shear strain in VEM for other modes. The affected shear strain in VEM altered the vibrational strain energy distribution and changed the receptance amplitude of different modes. In addition to apply the VEM where it is significantly strained, the analysis revealed that constraining the shear strain in VEM resulted in reduced receptance amplitude for different modes. The changes of receptance will further affect the vibration conditions in machining.

  • 21.
    Fu, Qilin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Rashid, Amir
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Joint interface characterization method using frequency response measurements on assembled structures only: theoretical development and experimental validation on a workholding fixture for machining2015In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 77, no 5-8, p. 1213-1228Article in journal (Refereed)
    Abstract [en]

    A computation model based on inverse receptance coupling method is presented in this paper aiming for obtaining the joint interface's stiffness and damping properties using frequency response functions measured on assembled structures only. In the model, it is emphasized that the joint stiffness and damping should be modeled with frequency dependency. The model's validity is checked both through finite element (FE) simulation and experimental analyses. In the FE simulation example, the computation model gives more accurate results with noise-free data. In the experimental example, where noise in the data is unavoidable, the computation model is explored further for its applicability in the real industrial environment. Results from applications of the computational model show that it is even capable of obtaining the joint interface stiffness and damping values over the structure's resonance frequency. A viable process of predicting behaviors of workpiece with receptance coupling method through identifying the joint interface properties is presented in the end of the paper. The applicability of this computation model and the factors that influence the accuracy of the model are discussed in the end of the paper.

  • 22.
    Ghassemali, Ehsan
    et al.
    School of Mechanical and Aerospace Engineering, Nanyang Technological University and Singapore Institute of Manufacturing Technology (SIMTech).
    Tan, Ming-Jen
    School of Mechanical and Aerospace Engineering, Nanyang Technological University.
    Jarfors, Anders E.W.
    Jönköping University, School of Engineering, JTH, Materials and Manufacturing. Jönköping University, School of Engineering, JTH. Research area Materials and manufacturing – Casting.
    Lim, S.C.V.
    Singapore Institute of Manufacturing Technology (SIMTech).
    Progressive microforming process: Towards the mass production of micro-parts using sheet metal2013In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 66, no 5-8, p. 611-621Article in journal (Refereed)
    Abstract [en]

    Although there is considerable published literature on micro-metal forming processes, there is still a lack of research towards implementing these processes commercially. Some of the challenges are handling of micro-parts and process intermittency. This work demonstrates the feasibility of producing symmetric micro-parts using a progressive forming set-up. Such a progressive forming process alleviates the challenges in handling and removal of micro-parts. Micro-pins with diameters of 0.3, 0.5, and 0.8 mm were successfully manufactured without defects. Experimental observations together with process simulation results showed that this process has three main stages: (1) indentation at the very beginning, (2) upsetting, and (3) extrusion predominantly occurring at the very end stage of the stroke. The bulk of the pin forming occurs at the end stroke of the process (extrusion stage). The effects of punch/pin diameter ratio on the pin aspect ratio and the maximum forming load were also investigated. In addition, the finite element results also revealed that a hybrid friction model was required to be implemented for better fit with experimental results as compared to the shear and Coulomb friction models.

  • 23.
    Glorieux, Emile
    et al.
    University West, Department of Engineering Science, Division of Automation Systems.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Automation Systems.
    Svensson, Bo
    University West, Department of Engineering Science, Division of Automation Systems.
    Lennartson, Bengt
    University West, Department of Engineering Science, Division of Automation Systems. Chalmers University of Technology, Department of Signals and Systems, Gothenburg, Sweden.
    Constructive cooperative coevolutionary optimisation for interacting production stations2015In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 78, no 1-4, p. 673-688Article in journal (Refereed)
    Abstract [en]

    Optimisation of the control function for multiple automated interacting production stations is a complex problem, even for skilled and experienced operators or process planners. When using mathematical optimisation techniques, it often becomes necessary to use simulation models to represent the problem because of the high complexity (i.e. simulation-based optimisation). Standard optimisation techniques are likely to either exceed the practical time frame or under-perform compared to the manual tuning by the operators or process planners. This paper presents the Constructive cooperative coevolutionary (C3) algorithm, which objective is to enable effective simulation-based optimisation for the control of automated interacting production stations within a practical time frame. C3 is inspired by an existing cooperative coevolutionary algorithm. Thereby, it embeds an algorithm that optimises subproblems separately. C3 also incorporates a novel constructive heuristic to find good initial solutions and thereby expedite the optimisation. In this work, two industrial optimisation problems, involving interaction production stations, with different sizes are used to evaluate C3. The results illustrate that with C3, it is possible to optimise these problems within a practical time frame and obtain a better solution compared to manual tuning.

  • 24.
    Hardwick, Martin
    et al.
    Department of Computer Science, Rensselaer Polytechnic.
    Zhao, Yaoyao Fiona
    Department of Mechanical Engineering, McGill University.
    Proctor, Frederick M.
    Intelligent Systems Division, The National Institute of Standards and Technology NIST.
    Nassehi, Aydin
    Department of Mechanical Engineering, University of Bath.
    Xu, Xun
    Department of Mechanical Engineering, University of Auckland.
    Venkatesh, Sid
    Boeing Company.
    Odendahl, David
    Boeing Company.
    Xu, Liangji
    Boeing Company.
    Hedlind, Mikael
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Computer Systems for Design and Manufacturing.
    Lundgren, Magnus
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Computer Systems for Design and Manufacturing.
    Maggiano, Larry
    Mitutoyo America Corporation.
    Loffredo, David
    STEP Tools Inc..
    Fritz, Jochim
    STEP Tools Inc..
    Olsson, Bengt
    Sandvik Coromant.
    Garrido, Julio
    Vigo University.
    Brail, Alain
    Airbus.
    A roadmap for STEP-NC-enabled interoperable manufacturing2013In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 68, no 5-8, p. 1023-1037Article in journal (Refereed)
    Abstract [en]

    The STEP-NC-AP 238 and ISO 14649 standard is the result of a 10-year international effort to replace the RS274D (ISO 6983) G and M code standard with a modern associative language that connects the CAD design data used to determine the machining requirements for an operation with the CAM process data that is used in creating a machining solution to satisfy these requirements. STEP-NC builds on the previous 10 years effort to develop the STEP neutral data standard for CAD data, and uses the modern geometric constructs in that standard to specify device independent tool paths, and CAM independent volume removal features. STEP-Manufacturing, Team 24 in Working Group 3 (WG3) of ISO TC184/SC4, is developing and validating the STEP-NC standard in liaison with Working Group (WG7) of ISO TC184/SC1 who provides the domain-specific input (ISO 14649) used within the standard. This paper reviews the demonstrations carried out by STEP-Manufacturing over the past 10 years. These demonstrations have been international collaborations between industry, academia, and research agencies. Each demonstration focused on extending the STEP-NC data model for a different application.

  • 25.
    Holmberg, Jonas
    et al.
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing. Manufacturing Swerea IVF AB Mölndal Sweden.
    Wretland, Anders
    GKN Aerospace Sweden AB Trollhättan Sweden.
    Berglund, Johan
    Manufacturing Swerea IVF AB Mölndal Sweden.
    Beno, Tomas
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Surface integrity after post processing of EDM processed Inconel 718 shaft2018In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 95, no 5-8, p. 2325-2337Article in journal (Refereed)
    Abstract [en]

    Electrical discharge machining (EDM) is considered as an efficient alternative to conventional material removal concepts that allows for much higher material removal rates. However, EDM generates unwanted features such as re-cast layer (RCL), tensile residual stresses and a rough surface. In order to recover the surface integrity, different post processes has been compared: high-pressure water jet (HPWJ), grit blasting (GB) and shot peening (SP). Surface integrity has been evaluated regarding microstructure, residual stresses, chemical content and surface roughness. The results showed that a combination of two post processes is required in order to restore an EDM processed surface of discontinuous islands of RCL. HPWJ was superior for removing RCL closely followed by grit blasting. However, grit blasting showed embedded grit blasting abrasive into the surface. Regarding surface roughness, it was shown that both grit blasting and HPWJ caused a roughening of the surface topography while shot peening generates a comparably smoother surface. All three post processes showed compressive residual stresses in the surface where shot peening generated the highest amplitude and penetration depths. However, the microstructure close to the surface revealed that shot peening had generated cracks parallel to the surface. The results strongly state how important it is to evaluate the surface at each of the different subsequent process steps in order to avoid initiation of cracks.

  • 26.
    Holmberg, Jonas
    et al.
    RISE - Research Institutes of Sweden, Swerea, Swerea IVF. University West, Sweden.
    Wretland, Anders
    GKN Aerospace Sweden AB, Sweden.
    Berglund, Jonas
    RISE - Research Institutes of Sweden, Swerea, Swerea IVF.
    Beno, Tomas
    University West, Sweden.
    Surface integrity after post processing of EDM processed Inconel 718 shaft2017In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 95, no 5-8, p. 2325-2337Article in journal (Refereed)
    Abstract [en]

    Electrical discharge machining (EDM) is considered as an efficient alternative to conventional material removal concepts that allows for much higher material removal rates. However, EDM generates unwanted features such as re-cast layer (RCL), tensile residual stresses and a rough surface. In order to recover the surface integrity, different post processes has been compared: high-pressure water jet (HPWJ), grit blasting (GB) and shot peening (SP). Surface integrity has been evaluated regarding microstructure, residual stresses, chemical content and surface roughness. The results showed that a combination of two post processes is required in order to restore an EDM processed surface of discontinuous islands of RCL. HPWJ was superior for removing RCL closely followed by grit blasting. However, grit blasting showed embedded grit blasting abrasive into the surface. Regarding surface roughness, it was shown that both grit blasting and HPWJ caused a roughening of the surface topography while shot peening generates a comparably smoother surface. All three post processes showed compressive residual stresses in the surface where shot peening generated the highest amplitude and penetration depths. However, the microstructure close to the surface revealed that shot peening had generated cracks parallel to the surface. The results strongly state how important it is to evaluate the surface at each of the different subsequent process steps in order to avoid initiation of cracks. © 2017 The Author(s)

  • 27. Ji, W.
    et al.
    Liu, X.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Wang, G.
    Research on modelling of ball-nosed end mill with chamfered cutting edge for 5-axis grinding2016In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 87, no 9-12Article in journal (Refereed)
    Abstract [en]

    This paper presents models related to the manufacturing of ball-nosed end mills of solid carbide (BEMSC) with a chamfered cutting edge (CCE). A parallel grinding wheel (PGW) is selected, and the relationship between CCE face and PGW working face is determined. Based on the geometry models of BEMSC established in our previous work, the centre and axis vectors of PGW are calculated for the grinding of CCE face on bath the ball-nosed end and the cylinder, which is validated through a numerical simulation. In order to produce the tool, a grinding machine, SAACKE UMIF, is chosen. Targeting the grinding data of BEMSC, the transformations are carried out between the coordinate systems of workpiece and the NC programme according to the structural features of the machine. An algorithm is derived for dispersing grinding paths. As a result, the centre data and axis vector are generated with respect to the grinding machine. The BEMSC with CCE is machined using the selected machine, which demonstrates the correctness of the established models. Finally, the performance of the machined cutting tool is validated in comparison with a common BEMSC without CCE in the milling of a mould of a multi-hardness joint structure.

  • 28.
    Ji, Wei
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering. Harbin Univ Sci & Technol, Harbin 150080, Peoples R China.
    Liu, Xianli
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering. Harbin Univ Sci & Technol, Harbin 150080, Peoples R China.
    Sun, Shilong
    Experimental evaluation of polycrystalline diamond (PCD) tool geometries at high feed rate in milling of titanium alloy TC112015In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 77, no 9-12, p. 1549-1555Article in journal (Refereed)
    Abstract [en]

    Titanium alloys are widely used in aerospace industrial components characterised by high material removal rate, of which the machining efficiency is a big issue. Targeting the problem, this paper presents the experimental findings of milling of titanium alloy TC11 using polycrystalline diamond (PCD) cutting tool at high feed rate. First, in order to verify the capability of PCD in finish milling of titanium alloys at high feed rate, the surface roughness R-a is investigated under different PCD tool geometries (radial rake angle, axial rake angle and insert sharp radius), and the results indicate that its range is from 0.821 to 1.562 mu m, which is suitable to titanium components. Also, the main tool failure patterns, cutting edge fracture and flank face wear, are observed and classified. Based on the tool failure patterns, the relationship between tool life and tool geometries is established. In order to explain the reasons of tool failures, the relationships between cutting forces and the tool geometries are made clear. Finally, the processes of flank face wear and rake face wear of PCD insert are proposed to show its wear evaluations.

  • 29.
    Karimi Neghlani, Paria
    et al.
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Raza, Tahira
    University West, Department of Engineering Science, Division of Welding Technology.
    Andersson, Joel
    University West, Department of Engineering Science, Division of Welding Technology.
    Svensson, Lars-Erik
    University West, Department of Engineering Science, Division of Welding Technology.
    Influence of laser exposure time and point distance on 75-μm-thick layer of selective laser melted Alloy 7182018In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 94, no 5-8, p. 2199-2207Article in journal (Refereed)
    Abstract [en]

    A systematic matrix with 25 samples, using five different point distances and five laser exposure times, depositing 75-μm-thick layers of Alloy 718 has been studied. The work has concentrated on defects formed, hardness of the deposits, and the microstructure. Relatively large amount of defects, both lack of fusion and porosity, was found in several of the specimens in the deposits. The defects were never possible to fully eliminate, but a significant decrease, mainly in the lack of fusion, was seen with increasing laser exposure time. The gas porosity on the other hand was not affected to any larger degree, except for the lowest laser energy input, where a slight increase in porosity was seen. A small increase in hardness was noted with increasing laser energy input. The width of the deposited beads increased with increasing laser energy, while the depth of deposits was more or less constant. However, for the lowest combination of point distance and laser exposure time, quite deep and narrow beads were formed. A comparison was made with deposition of 50-μm-thick layers, with quite similar laser energy input, but with some variation in detailed deposition parameters. It was found that the 75-μm-thick layers contained less lack of fusion, particularly for small point distances. The amount of porosity was also less, but that did not vary with deposition parameters.© 2017 The Author(s)

  • 30.
    Kjellander, Johan A. P.
    et al.
    Örebro University, School of Science and Technology.
    Rahayem, Mohamed
    Örebro University, School of Science and Technology.
    Planar segmentation of data from a laser profile scanner mounted on an industrial robot2009In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 45, no 1-2, p. 181-190Article in journal (Refereed)
    Abstract [en]

    In industrial applications like rapid prototyping, robot vision, and geometric reverse engineering, where speed and automatic operation are important, an industrial robot and a laser profile scanner can be used as a 3D measurement system. This paper is concerned with the problem of segmenting the data from such a system into regions that can be fitted with planar surfaces. We have developed a new algorithm for planar segmentation based on laser scan profiles and robot poses. Compared to a traditional algorithm that operates on a point cloud, the new algorithm is shown to be more effective and faster.

  • 31.
    Li, Peigang
    et al.
    ESAB AB, Gothenburg, Sweden.
    Hurtig, Kjell
    University West, Department of Engineering Science, Division of Welding Technology.
    Högström, Mats
    University West, Department of Engineering Science, Division of Welding Technology.
    Svensson, Lars-Erik
    University West, Department of Engineering Science, Division of Welding Technology.
    Scotti, Americo
    University West, Department of Engineering Science, Division of Welding Technology.
    A contribution to the study of negative polarity in GMA welding2018In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 95, no 5-8, p. 2543-2553Article in journal (Refereed)
    Abstract [en]

    GMAW using the electrode with negative polarity (DCEN) has been frequently suggested as a potential means of increasing production capacity. The objective of this work was to further study the performance of negative polarity in GMAW of carbon steels. In this project phase, bead-on-plate welds were carried out in flat position to assess the effect of different potential shielding gas compositions on bead geometry, finishing and spattering. The characteristics were compared with DCEP at the same current, but depositing the same volume of material per unit of length (more industrial related comparison). The arc length was kept the same by adjusting voltage to reach shortest arcs, yet with suitable non short-circuiting metal transfer mode. An approach to measure bead convexity was also proposed and assessed. The results showed that DCEN is feasible as a means of increasing GMAW production capacity. However, to become DCEN applicable with GMAW, the results suggest an Ar based blend with around 6.5 % of O2 is the most appropriate shielding gas, as much as that there is a demand for a standard electronic controlled power source able to work in constant current mode. 

  • 32.
    Lieder, Michael
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    A. Asif, Farazee M.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Rashid, Amir
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Mihelič, Aleš
    Gorenje d.d..
    Kotnik, Simon
    Gorenje d.d..
    Towards circular economy implementation in manufacturing systems using a multimethod simulation approach to link design and business strategy2017In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 93, no 5-8, p. 1953-1970Article in journal (Refereed)
    Abstract [en]

    The recent circular economy movement has raised awareness and interest about untapped environmental and economic potential in the manufacturing industry. One of the crucial aspects in the implementation of circular or closed-loop manufacturing approach is the design of circular products. While it is obvious that three post-use strategies, i.e., reuse, remanufacturing, and recycling, are highly relevant to achieve loop closure, it is enormously challenging to choose “the right” strategy (if at all) during the early design stage and especially at the single component level. One reason is that economic and environmental impacts of adapting these strategies are not explicit as they vary depending on the chosen business model and associated supply chains. In this scenario, decision support is essential to motivate adaptation of regenerative design strategies. The main purpose of this paper is to provide reliable decision support at the intersection of multiple lifecycle design and business models in the circular economy context to identify effects on cost and CO2 emissions. The development of this work consists of a systematic method to quantify design effort for different circular design options through a multi-method simulation approach. The simulation model combines an agent-based product architecture and a discrete event closed-loop supply chain model. Feasibility of the model is tested using a case of a washing machine provided by Gorenje d.d. Firstly, design efforts for reuse, remanufacturing, and recycling are quantified. Secondly, cost and emissions of different design options are explored with different business model configurations. Finally, an optimization experiment is run to identify the most cost-effective combination of reused, remanufactured, and recycled components for a business model chosen on the basis of the explorative study results.

  • 33.
    Liu, J.
    et al.
    School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore.
    Tan, M. -J
    School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore.
    Aue-U-Lan, Y.
    Singapore Institute of Manufacturing Technology.
    Jarfors, A. E. W.
    Singapore Institute of Manufacturing Technology.
    Fong, K. -S
    Singapore Institute of Manufacturing Technology.
    Castagne, S.
    Singapore Institute of Manufacturing Technology.
    Superplastic-like forming of non-superplastic AA5083 combined with mechanical pre-forming2011In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 52, no 1-4, p. 123-129Article in journal (Refereed)
    Abstract [en]

    Superplastic forming has been considered as an attractive process in the automotive and aerospace industries. However, the disadvantages of slow forming rate, high-temperature requirement, poor thickness distribution, and expensive base material have hindered its widespread use for high production volume. In this paper, the non-superplastic grade of 5083 aluminum alloy (AA5083) sheets with thickness of 3 mm was employed in a superplastic-like forming process, which is a combination of drawing (mechanical pre-forming) and superplastic forming (blow forming). Experimental trials were conducted to verify the possibility of improving the forming rate and lowering the process temperature. The blank was firstly pre-formed during the mechanical pre-forming phase. As a result, some part of material along the flange area was introduced inside the deformation cavity in advance of the blow forming phase. Secondly, argon gas was applied on the sheet, which would be deformed to come into contact with the inner die surface at the end of pressure cycle. It took only 8 min for the blow forming phase, and the process achieved an almost fully formed part at 400°C. The minimum thickness occurred at the inward corners, and the maximum thinning of the formed part was 54%. Grain growth and cavitation were found from the microstructure observations.

  • 34. Maalouf, Maher
    et al.
    Barsoum, Zuheir
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Lightweight Structures.
    Failure strength prediction of aluminum spot-welded joints using kernel ridge regression2017In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 91, no 9-12, p. 3717-3725Article in journal (Refereed)
    Abstract [en]

    The current paper presents an alternative method for failure strength prediction of spot-welded joints in aluminum, based on nonlinear regression analysis, namely, the kernel ridge regression method. Welding parameters such as electrode force, welding current, and welding time are studied in the experimental investigation to measure their effects on the nugget size and failure strength of the resistance spot welds. Coupons are manufactured and tensile tested and the results show that the welding current and time have the largest effect on the nugget size and the failure strength. The results of this study are compared to those of the least squares method and they indicate that the truncated-regularized kernel ridge regression algorithm significantly improves the coefficient of determination and reduces the mean squared error.

  • 35.
    Meng, Yue
    et al.
    Harbin Univ Sci & Technol, Sch Mech & Power Engn, Harbin 150080, Heilongjiang, Peoples R China..
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Production Systems.
    Lee, Chen-Han
    Huazhong Univ Sci & Technol, Sch Mech Sci & Engn, Wuhan 430000, Hubei, Peoples R China..
    Ji, Wei
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Liu, Xianli
    Harbin Univ Sci & Technol, Sch Mech & Power Engn, Harbin 150080, Heilongjiang, Peoples R China..
    Plastic deformation-based energy consumption modelling for machining2018In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 96, no 1-4, p. 631-641Article in journal (Refereed)
    Abstract [en]

    To predict energy consumption in machining, a mathematical modelling method to mimic the cutting energy consumption during machining is proposed in this paper. The established model is based on the law of energy conservation. The mechanical material property coefficients and cutting parameters are included in the model by using material deformation theory and friction calculation which are used to represent the phenomena in machining. Cutting energy of material removal process is refined by analysing the effect of tool edge geometry. In addition, the machining process is divided into two machining elements, linear element and circular arc element, of which energy consumptions are established based on the principal theories above. Calculation method on the instantaneous cutting thickness for circular arc elements is proposed. Finally, a test example is given to validate the proposed modelling approach. With the proposed method, the separate impacts of the factors (e.g. cutting parameters, workpiece, tool) have been analysed and the physical background behind the known experimental dependence of the cutting parameters on cutting energy is revealed.

  • 36.
    M'Saoubi, R.
    et al.
    Seco Tools AB.
    Chandrasekaran, Hariharan
    RISE, Swerea, Swerea KIMAB.
    Hutchinson, Bevis
    RISE, Swerea, Swerea KIMAB.
    Experimental study and modelling of tool temperature distribution in orthogonal cutting of AISI 316L and AISI 3115 steels2011In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 56, p. 865-877Article in journal (Refereed)
    Abstract [en]

    Cutting tool temperature distribution was mapped using the IR-CCD technique during machining of carbon steel AISI 3115 and stainless steel AISI 316L under orthogonal cutting conditions using flat-face geometry inserts. The effect of work material treatment on tool temperature was investigated, and the results showed that AISI 3115 in heat-treated state displayed higher tool temperature than the as-rolled state. Stainless steel 316L with high sulphur content (0.027 wt.%) and calcium treatment displayed lower cutting tool temperature than the variant with low sulphur (0.009 wt.%). The experimental results were compared with theoretical tool temperature distributions based on a modified version of Komanduri and Hou's analytical model. In particular, variable frictional heat source and secondary shear were introduced and modelling of the tool stress distribution on rake surface was also considered. © 2011 Springer-Verlag London Limited.

  • 37.
    Oosthuizen, Gert Adriaan
    et al.
    Department of Industrial Engineering, University of Stellenbosch, Maiteland, South Africa.
    Akdogan, Guven
    Department of Industrial Engineering, University of Stellenbosch, Maiteland, South Africa.
    Treurnicht, Nico
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    The performance of PCD tools in high-speed milling of Ti6Al4V2011In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 52, no 9-12, p. 929-935Article in journal (Refereed)
    Abstract [en]

    Tool performance of conventional tools is poor and a major constraint when used in milling titanium alloys at elevated cutting speeds. At these high cutting speeds, the chemical and mechanical properties of Ti6Al4V cause complex wear mechanisms. In this paper, a fine-grain polycrystalline diamond (PCD) end mill tool was tested, and its wear behavior was studied. The performance of the PCD tool has been investigated in terms of tool life, cutting forces, and surface roughness. The PCD tool yielded longer tool life than a coated carbide tool at cutting speeds above 100 m/min. A slower wear progression was found with an increase in cutting speeds, whereas the norm is an exponential increase in tool wear at elevated speeds. Observations based on scanning electron microscope (SEM) and energy dispersive spectroscopy (EDAX) analysis suggest that adhesion of the workpiece is the wear main type, after which degradation of the tools accelerates probable due to the combined effect of high temperature degradation coupled with abrasion.

  • 38.
    Paras, Manoj Kumar
    et al.
    University of Borås, Faculty of Textiles, Engineering and Business.
    Pal, Rudrajeet
    University of Borås, Faculty of Textiles, Engineering and Business.
    Application of Markov chain for LCA: a study on the clothes 'reuse' in Nordic countries2017In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015Article in journal (Refereed)
    Abstract [en]

    The purpose of this paper is to develop a model to count the number of cycles or trips that a clothing product could make in a reuse-based closed loop cycle. The model is primarily based on three scenarios: (i) self-reuse (ii) discard to second-hand market and (iii) disposed to incineration or the recycling stations. The present study extended and complemented the existing literature by presenting the application of the Markov chain to analyse the future of textile products on the basis of probabilities. Subsequently, the proposed model has been used to study the textile waste flow in the Nordic countries, i.e. Denmark, Finland, Iceland, Norway and Sweden. The application of the proposed model on the data from the Nordic Countries indicated that the average number of times the clothes reuse is highest in Denmark, whereas the lowest was found in Finland. Repair and redesign were found a hotspot for the recovery of clothes. Variation in these hotspots can increase the trip number of clothes. A sensitivity analysis is performed and conclusions are made regarding variations of clothes reuse under different scenarios. The proposed model may help in the decision formulation for the companies, government authorities and research agencies which focus on reuse and recycling of textile products. Based on the insights from the present work, the decision maker may take several initiatives to increase the life span of a textile product.

  • 39.
    Parsian, Amir
    et al.
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Magnevall, Martin
    AB Sandvik Coromant, SE-811 81 Sandviken, Sweden..
    Beno, Tomas
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Eynian, Mahdi
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Time Domain Simulation of Chatter Vibrations in Indexable Drills2017In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 89, no 1-4, p. 1209-1221Article in journal (Refereed)
    Abstract [en]

    Regenerative chatter vibrations are common in drilling processes. These unwanted vibrations lead to considerable noise levels, damage the quality of the workpiece, and reduce tool life. The aim of this study is to simulate torsional and axial chatter vibrations as they play important roles in dynamic behavior of indexable insert drills with helical chip flutes. While asymmetric indexable drills are not the focal points in most of previous researches, this paper proposes a simulation routine which is adapted for indexable drills. Based on the theory of regenerative chatter vibration, a model is developed to include the asymmetric geometries and loadings that are inherent in the design of many indexable insert drills. Most indexable insert drills have two inserts located at different radial distances, namely central and peripheral inserts. Since the positions of the central and peripheral inserts are different, the displacement and thereby the change in chip thickness differs between the inserts. Additionally, the inserts have different geometries and cutting conditions, e.g., rake angle, coating, and cutting speed, which result in different cutting forces. This paper presents a time-domain simulation of torsional and axial vibrations by considering the differences in dynamics, cutting conditions, and cutting resistance for the central and peripheral inserts on the drill. The time-domain approach is chosen to be able to include nonlinearities in the model arising from the inserts jumping out of cut, multiple delays, backward motions of edges, and variable time delays in the system. The model is used to simulate cutting forces produced by each insert and responses of the system, in the form of displacements, to these forces. It is shown that displacements induced by dynamic torques are larger than those induced by dynamic axial forces. Finally, the vibration of a measurement point is simulated which is favorably comparable to the measurement results.

  • 40.
    Pervaiz, Salman
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Machine and Process Technology.
    Deiab, Ibrahim
    University of Guelph, CANADA.
    Wahba, Essam
    Mechanical Engineering, American University of Sharjah.
    Rashid, Amir
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Machine and Process Technology.
    Nicolescu, Mihai
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Machine and Process Technology.
    A novel numerical modeling approach to determine the temperature distribution in the cutting tool using conjugate heat transfer (CHT) analysis2015In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 80, no 5, p. 1039-1047Article in journal (Refereed)
    Abstract [en]

    This study deals with the conjugate heat transfer problem of a single point cutting tool under turning operation dissipating heat in the tool material and streams of the surrounding air. In order to estimate the cutting temperature during the turning operation, the DEFORM-3D finite element package was utilized. A machining simulation material model for Ti6Al4V was utilized using a modified Johnson–Cook equation. The maximum cutting temperature value was obtained from the finite element model. The temperature was then used as a constant heat source on the tool tip, and the conjugate heat transfer (CHT) approach was used to develop a computational fluid dynamics (CFD) model. The CFD model utilized a 3D heat and fluid flow analysis using ANSYS ® CFX. A cutting insert with a constant heat source was exposed to the stream velocities of the dry air. The numerical equations governing the flow and thermal fields in the fluid domain and energy equation in the solid domain were solved in parallel by maintaining the continuity of temperature and heat flux at the solid–fluid interface. The presented conjugate heat transfer (CHT) approach provided a very useful understanding of the temperature profile development at the cutting tool that is still a complex challenge for the existing experimental and numerical techniques.

  • 41. Pervaiz, Salman
    et al.
    Deiab, Ibrahim
    Wahba, Essam
    Rashid, Amir
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Nicolescu, Mihai
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    A numerical and experimental study to investigate convective heat transfer and associated cutting temperature distribution in single point turning2018In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 94, no 1-4, p. 897-910Article in journal (Refereed)
    Abstract [en]

    During the metal cutting operation, heat generation at the cutting interface and the resulting heat distribution among tool, chip, workpiece, and cutting environment has a significant impact on the overall cutting process. Tool life, rate of tool wear, and dimensional accuracy of the machined surface are linked with the heat transfer. In order to develop a precise numerical model for machining, convective heat transfer coefficient is required to simulate the effect of a coolant. Previous literature provides a large operating range of values for the convective heat transfer coefficients, with no clear indication about the selection criterion. In this study, a coupling procedure based on finite element (FE) analysis and computational fluid dynamics (CFD) has been suggested to obtain the optimum value of the convective heat transfer coefficient. In this novel methodology, first the cutting temperature was attained from the FE-based simulation using a logical arbitrary value of convective heat transfer coefficient. The FE-based temperature result was taken as a heat source point on the solid domain of the cutting insert and computational fluid dynamics modeling was executed to examine the convective heat transfer coefficient under similar condition of air interaction. The methodology provided encouraging results by reducing error from 22 to 15% between the values of experimental and simulated cutting temperatures. The methodology revealed encouraging potential to investigate convective heat transfer coefficients under different cutting environments. The incorporation of CFD modeling technique in the area of metal cutting will also benefit other peers working in the similar areas of interest.

  • 42.
    Pervaiz, Salman
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Rashid, Amir
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Deiab, I.
    Nicolescu, Cornel M.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    An experimental investigation on effect of minimum quantity cooling lubrication (MQCL) in machining titanium alloy (Ti6Al4V)2016In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 87, no 5-8, p. 1371-1386Article in journal (Refereed)
    Abstract [en]

    During the machining operation, elevated temperatures are achieved at the cutting interface due to the presence of high plastic deformation and friction in between the tool and chip contacting area. Efficient heat dissipation from the cutting interface is required to achieve better machining performance. Elevated temperature in the cutting area results in lower tool life as it facilitates different types of wear mechanisms. Metal working fluids (MWFs) are employed to reduce heat and friction in the cutting zone, simultaneously to help in the flushing of waste particles. The MWFs are based on either water or petroleum oil and include several additives which make them non-biodegradable and toxic in nature. The minimum quantity lubrication (MQL) method offers a feasible substitute to the MWF-based conventional flood cooling method. In this study, a vegetable oil-based MQL system was mixed with sub-zero temperature air to design a new minimum quantity cooling lubrication (MQCL) system. The study investigates the machinability of Ti6Al4V using an MQCL system under various oil flow rates and compared its machining performance with both dry cutting and conventional flood cooling. For further evaluation, the study investigated surface roughness, flank wear, and associated wear mechanisms. It was found that in the MQCL system (60–70 ml/h), oil supply rates provided reliable machining performance at higher feed levels.

  • 43.
    Rahayem, Mohamed R.
    et al.
    Örebro University, School of Science and Technology.
    Kjellander, Johan A. P.
    Örebro University, School of Science and Technology.
    Quadric segmentation and fitting of data captured by a laser profile scanner mounted on an industrial robot2010In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 52, no 1-4, p. 155-169Article in journal (Refereed)
    Abstract [en]

    Applications like geometric reverse engineering, robot vision and automatic inspection require sets of points to be measured from the surfaces of objects and then processed by segmentation and fitting algorithms to establish shape parameters of interest. In industrial applications where speed, reliability and automatic operation is of interest a measuring system based on a laser profile scanner mounted on an industrial robot can be of interest. In earlier publications we have presented such a system and also a segmentation algorithm for planar surfaces using 2D profile data in combination with robot poses. Due to the data reduction offered by this approach the segmentation algorithm computes faster than algorithms based on 3D point sets alone. Encouraged by the results we have now developed a segmentation algorithm for two different quadric surfaces also based on 2D profiles in combination with robot poses. This paper presents the new algorithm together with test results and also an interesting observation that points to future work.

  • 44.
    Schmidt, Bernard
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Wang, Lihui
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. Department of Production Engineering, KTH Royal Institute of Technology, Stockholm, Sweden.
    Cloud-enhanced predictive maintenance2016In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015Article in journal (Refereed)
    Abstract [en]

    Maintenance of assembly and manufacturing equipment is crucial to ensure productivity, product quality, on-time delivery, and a safe working environment. Predictive maintenance is an approach that utilises the condition monitoring data to predict the future machine conditions and makes decisions upon this prediction. The main aim of the present research is to achieve an improvement in predictive condition-based maintenance decision making through a cloud-based approach with usage of wide information content. For the improvement, it is crucial to identify and track not only condition related data but also context data. Context data allows better utilisation of condition monitoring data as well as analysis based on a machine population. The objective of this paper is to outline the first steps of a framework and methodology to handle and process maintenance, production, and factory related data from the first lifecycle phase to the operation and maintenance phase. Initial case study aims to validate the work in the context of real industrial applications.

  • 45.
    Silva, Ana
    et al.
    University West, Department of Engineering Science, Division of Production System.
    De Backer, Jeroen
    University West, Department of Engineering Science, Division of Production System.
    Bolmsjö, Gunnar
    University West, Department of Engineering Science, Division of Production System.
    Temperature measurements during friction stir welding2017In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 88, no 9-12, p. 2899-2908Article in journal (Refereed)
    Abstract [en]

    The increasing industrial demand for lighter, more complex and multi-material components supports the development of novel joining processes with increased automation and process control. Friction stir welding (FSW) is such a process and has seen a fast development in several industries.This welding technique gives the opportunity of automation and online feedback control, allowing automatic adaptation to environmental and geometrical variations of the component.Weld temperature is related to the weld quality and therefore proposed to be used for feedback control. For this purpose, accurate temperature measurements are required. This paper presents an overview of temperature measurement methods applied to the FSW process. Three methods were evaluated in this work: thermocouples embedded in the tool, thermocouples embedded in the workpiece and the tool-workpiece thermocouple(TWT) method. The results show that TWT is an accurate and fast method suitable for feedback control of FSW.

  • 46.
    Svenman, Edvard
    et al.
    University West, Department of Engineering Science, Research Enviroment Production Technology West. GKN Aerospace.
    Runnemalm, Anna
    University West, Department of Engineering Science, Division of Production System.
    A complex response inductive method for improved gap measurement in laser welding2017In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 88, no 1-4, p. 175-184Article in journal (Refereed)
    Abstract [en]

    Laser welding needs precise measurement of weldgap position to avoid weld defects. Most often, optical measurement methods are used, but well-aligned narrow gaps canbe difficult to detect. An improved inductive method capable of detecting zero gaps in square butt joints is proposed. The new method uses two eddy current coils, one on each side of the gap, and measures the complex response of the individual coils, i.e. both the inductive and resistive response. By combining the coil responses, both the position and the geometry of the weld gap can be estimated. The method was experimentally investigated by traversing a single coil over an adjustable gap between two plates and combining the measured coil responses into a simulated two-coil probe. The gap was adjusted in both misalignment and gap width up to 0.4 mm. Comparing the results to known settings and positions shows that gap position is measured to within 0.1 mm, if the probe is within a working area of 1 mm from the gap in both position and height. Results from the new method were compared to simulations, from the same experimental data, of a previously reported method where the coils were electrically combined by wiring them together. The previous method can give accurate results but has a much smaller working area and depends on servo actuation to position the probe above the gap. The improved method gives better tolerance to varying misalignment and gap width, which is an advantage over previous inductive methods.

  • 47.
    Svensson, Bo
    et al.
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Lennartson, Bengt
    University West, Department of Engineering Science, Division of Automation and Computer Engineering. University West, Department of Engineering Science, Division of Production System.
    An efficient algorithm for press line optimisation2013In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 68, no 5, p. 1627-1638Article in journal (Refereed)
    Abstract [en]

    Automated manufacturing processes such as automotive tandem press lines include time dependent complex control functions. All motions and critical interactions between moving parts must be synchronised to avoid collisions and reach high production rate. It is even for a skilled operator hard to optimise these processes on-line. Therefore, a hardware-in-the-loop simulation including real industrial control systems and its control code establish an essential tool for optimisation. Additionally, an efficient optimisation algorithm is required to reach a useful simulation-based optimisation method. This paper proposes a new optimisation algorithm starting with the Lipschitzian algorithm DIRECT as global search and then switches over to the Nelder-Mead simplex algorithm for local convergence. During the switch over, the new algorithm determines all local candidates of the set of points evaluated by DIRECT and starts multiple Nelder-Mead local searches in each of these. An optimisation study for an automotive press line shows that the proposed algorithm combines the benefits of the Lipschitzian and the simplex algorithms in an efficient way. The importance of multiple local searches from all local candidates found is also shown in the study. Based on the same number of function evaluations, it is also shown that this algorithm reaches improved press line performances compared to the stochastic differential evolution algorithm.

  • 48.
    Takami, Kourosh Mousavi
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Mahmoudi, Jafar
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Dahlquist, Erik
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Adaptive control of cold rolling system in electrical strips production system with online-offline predictors2010In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 50, no 9-12, p. 917-930Article in journal (Refereed)
    Abstract [en]

    One of the main concerns of strips producers is to measure strip thickness accurately as it is produced. Correct modelling of the sensitivity of output variables to input variables in a rolling mill model is one of the keys to obtaining more accurate data. An adaptive control system that uses an artificial neural network (ANN) creates a model of the process directly from measurement data. Using the model, the control system can predict how the process will react to control actions. The creation of the model and the computation of the control strategy are carried out automatically by the control system. The proportional-integral-derivative controller is used in this method to increase accuracy of final estimated variables and to increase accuracy of control of the system. To determine the correct tuning for thickness control, three control parameters are considered: the roll gap, and front and back tensions. A predictive model is used, based on the sensitivity equations of the process, where the sensitivity factors are computed by differentiating a previously trained neural network. Results of a case study in a real plant show that this online-offline model is effective in reducing thickness variations in produced strips.

  • 49.
    Takami, Kourosh Mousavi
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Mahmoudi, Jafar
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Dahlquist, Erik
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Lindenmo, Magnus
    Cogent Power Ltd, Surahammars Bruk.
    Multivariable data analysis of a cold rolling control system to minimise defects2011In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 54, no 5-8, p. 553-565Article in journal (Refereed)
    Abstract [en]

    This paper focuses on the application of principal component analysis (PCA) to thoroughly analyse and interpret multidimensional data from a cold rolling process. The analysis includes the effects of variables on the final properties of strips in a cold rolling mill. Unscrambler software was used to analyse and identify hidden variables. Variable correlations were also used to derive correlations between the control parameters. The results of this research will be used to improve the selection of material in order to reduce the occurrence of defects in the cold rolling process and to improve the adjustment of the set points that are performed in every pass or section of the cold rolling process. The hot rolled strips that enter the cold rolling mill are made of different materials and are produced by different strip manufacturers. Some strips break during the thickness reduction process in the cold rolling mill. This paper focuses on two possible causes of breakage: non-uniform strip material properties and failures in the rolling mill process. Two types of rolled strips (those that break and those that do not break) were compared to identify causes of breakage. The results indicate that breakages are caused by material or process failures. PCA was applied to the dataset in order to identify and analyse the relationships between the variables in the process. This information was used to interpret and diagnose the process behaviour. Swarm analysis and relating observations to process behaviour were able to distinguish between different start-up conditions, and between desirable and undesirable process conditions.

  • 50.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering. Harbin University of Science and Technology, Harbin, China.
    Collaborative robot monitoring and control for enhanced sustainability2015In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 81, no 9-12, p. 1433-1445Article in journal (Refereed)
    Abstract [en]

    This paper presents a new approach for real-time collaborations in adaptive manufacturing, including web-based remote monitoring and control of an industrial robot, and active collision avoidance for human-robot collaborations. It is enabled by using virtual 3D models driven by real sensor data and depth images of human operators. The objectives of this research are to significantly reduce network traffic needed for real-time monitoring over the Internet and to increase human safety in a human-robot coexisting environment. The ultimate goal is to enhance the sustainability of manufacturing operations in decentralised dynamic environments with safety protection. The results of a case study show that the approach consumes less than 1 % of network bandwidth of traditional camera-based methods and is feasible and practical as a web-based solution.

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