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  • 151.
    Liu, Yongkui
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Production Systems.
    Wang, Yuquan
    KTH.
    Wang, Xi Vincent
    KTH, Centres, XPRES, Excellence in production research. KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Production Systems.
    Zhang, L.
    China.
    Multi-agent-based scheduling in cloud manufacturing with dynamic task arrivals2018In: Procedia CIRP, Elsevier, 2018, p. 953-960Conference paper (Refereed)
    Abstract [en]

    Scheduling is a critical means for providing on-demand manufacturing services in cloud manufacturing. Multi-agent technologies provide an effective approach for addressing scheduling issues in cloud manufacturing, which, however, have rarely been used for solving the issue. This paper addresses scheduling issues in cloud manufacturing using multi-agent technologies. A multi-agent architecture for scheduling in cloud manufacturing is proposed firstly. Then, a corresponding multi-agent model is presented, which incorporates many-to-many negotiations based on an extended contract net protocol and takes into account dynamic task arrivals. Simulation results indicate the feasibility of the model and approach proposed.

  • 152. Liu, Zhenkai
    et al.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Production Systems. National Research Council of Canada.
    Sequencing of interacting prismatic machining features for process planning2007In: Computers in industry (Print), ISSN 0166-3615, E-ISSN 1872-6194, Vol. 58, no 4, p. 295-303Article in journal (Refereed)
    Abstract [en]

    oday, feature-based process planning has been popular in academia and industry with its ability to rigorously integrate design and manufacturing. To date, research on feature sequencing is mainly focused on using expert systems or knowledge-based systems, geometric based approaches, unsupervised-leaming or artificial neural network, and genetic algorithms. The approach presented in this paper, however, is a hybrid one using both knowledge-based rules and geometric reasoning rules. In addition to feature sequencing rules formulation, our research contributions consist of: (1) determining machining precedence constraints by a set of defined knowledge-based rules, (2) grouping machining features into setups based on tool approaching directions, and (3) sequencing features within each setup through geometric reasoning. The sequence of materials (features) to be removed depends on two types of interactions: adjacent interaction and volumetric interaction. A set of rules for geometric reasoning is therefore developed to generate feature sequence. The developed approach has been implemented as the Sequence Generator module in a Distributed Process Planning system and is validated through a case study.

  • 153. Liu, Zhenkai
    et al.
    Wang, Lihui
    Integrated Manufacturing Technologies Institute, National Research Council Canada.
    Lu, B.
    Integrating Cross-sectional Imaging based Reverse Engineering with Rapid Prototyping2006In: Computers in industry (Print), ISSN 0166-3615, E-ISSN 1872-6194, Vol. 57, no 2, p. 131-140Article in journal (Refereed)
    Abstract [en]

    This paper presents an integrated system of cross-sectional imaging based reverse engineering (RE) and rapid prototyping (RP) for reproducing complex objects. The system consists of four modules: cross-sectional image measurement, 3D reconstruction, stereo lithography (STL) file generation, and RP slice file generation. During cross-sectional image measurement, the object to be measured is encased within resin and then milled, layer-by-layer, using an NC milling machine. After each layer is machined, a CCD camera is used to capture the newly exposed cross-sectional image of the object. The contours of the cross-sectional image are further extracted through image processing and segmentation. A collection of the contour data is acquired by the cross-sectional image measurement module. While a 3D CAD model can be reconstructed by the 3D reconstruction module from the contour data, its STL file and RP slice file are generated directly from the contour data. The algorithm for STL file generation from cross-sectional contours consists of three major steps: (1) preprocessing of cross-section images for data reduction, (2) Delaunay triangulation of contours in the first and last layers and (3) triangulation of contours between adjacent layers. This integrated system and the processing algorithms are further validated through four examples. Crown Copyright © 2005 Published by Elsevier B.V. All rights reserved.

  • 154. Liu, Zhenkai
    et al.
    Wang, Lihui
    Lu, Bin
    Rapid Reverse Engineering Based on Cross-sectional Images2004Conference paper (Refereed)
  • 155. Lu, B.
    et al.
    Li, B.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Yang, J.
    Liu, J.
    Wang, X. Vincent
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Reusability based on life cycle sustainability assessment: Case study on WEEE2014Conference paper (Refereed)
    Abstract [en]

    Reuse is one of the key strategies of Waste Electrical and Electronic Equipment (WEEE) recycling system in China. Reuse can help realize eco-efficient and sustainable WEEE management, with environmentally friendly materials recovery. At present, reusability of products and components is determined only by the products functional situation or the economic cost benefit analysis. It does not cover all the three pillars of sustainability, including environment, economy and society. In this study, the emerging integrated method, Life Cycle Sustainability Assessment (LCSA), is employed to measure reusability of typical electrical and electronic products and components. The results of case studies show that, LCSA based reusability of typical electrical and electronic products and components will help improve WEEE management policy.

  • 156.
    Lu, Shaoping
    et al.
    Shenzhen Univ, Dept Transport & Logist, Shenzhen, Peoples R China..
    Xu, Chen
    Shenzhen Univ, Inst Intelligent Comp Sci, Shenzhen, Peoples R China..
    Zhong, Ray Y.
    Univ Auckland, Dept Mech Engn, Auckland, New Zealand..
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    A passive RFID tag-based locating and navigating approach for automated guided vehicle2018In: Computers & industrial engineering, ISSN 0360-8352, E-ISSN 1879-0550, Vol. 125, p. 628-636Article in journal (Refereed)
    Abstract [en]

    This research is motivated by the industrial applications of Cyber-physical System (CPS) such as smart warehouse and intelligent manufacturing which require the support of AGV (Automated Guided Vehicle). One of the key research is locating and navigating approach that should be with much flexibility for dealing with complex industrial applications. This paper takes a passive radio frequency identification (RFID) tag-based locating and navigating approach for AGV to examine the influences of tags, antennas, and environmental aspects. The approach was validated and a prototype system was built up. Several key observations are significant from the implementation and simulation study. Firstly, it is observed that adding angle reflector could eliminate the back lobe and restrain backward reflection. Secondly, RFID antenna center and the tag center should be designed at the same height could reduce the impact area of reflection. Lessons and insights from this study will be significant for industrial practitioners to implement AGVs in smart warehouse and manufacturing management.

  • 157. Ma, J.
    et al.
    Feng, H.-Y.
    Wang, Lihui
    University of Skövde.
    Normal Vector Estimation for Point Clouds via Local Delaunay Triangle Mesh Matching2013In: Computer-Aided Design and Applications, ISSN 1686-4360, Vol. 10, no 3, p. 399-411Article in journal (Refereed)
    Abstract [en]

    Reliable estimation of normal vectors for point clouds is of practical importance in computer-aided geometric modeling and inspection. This paper introduces a new normal vector estimation method for point clouds based on the matching results of the local Delaunay triangle mesh formed at each point. The local mesh is a manifold patch of Delaunay triangles and resembles an open umbrella. According to the matching results of these umbrellas, the local Delaunay neighbors at each point can be reliably identified, which leads to accurate normal vector calculations. Compared with the existing methods, the proposed method yields normal vectors of notably improved accuracy, especially for points near edge or corner features. The improvement has been demonstrated using both simulated and scanned point cloud data sets.

  • 158. Ma, Ji
    et al.
    Feng, Hsi-Yung
    Wang, Lihui
    University of Skövde.
    Delaunay-Based Triangular Surface Reconstruction from Points via Umbrella Facet Matching2010Conference paper (Refereed)
    Abstract [en]

    This paper presents an effective algorithm to reconstruct a closed 3D triangular surface mesh from a set of unorganized points based on Delaunay triangles. The algorithm essentially seeks to construct an optimal local 2D manifold surface (umbrella) at each individual point in parallel. The underlying principle is that for any point, there always exists a cluster of triangular facets, selected from the Delaunay triangles at the point, to constitute the shape of an opened umbrella. If a triangular facet belongs to all three umbrellas of its three vertices, the triangular facet is considered as a matched facet. When all triangular facets of an umbrella are matched facets, the umbrella is regarded as a matched umbrella which fully overlaps with its neighboring umbrellas. A topologically correct triangular surface mesh is then constructed when the matched umbrella for every individual point is found. The proposed Umbrella Facet Matching (UFM) algorithm has been implemented and validated using many publicly available point cloud data sets. The algorithm is seen to be of good convergence and without the need for further hole-filling post-processing. And the reconstructed surface meshes only contain minor shape approximation errors, when compared to the original surfaces of the sampled points.

  • 159. Ma, Ji
    et al.
    Feng, Hsi-Yung
    Wang, Lihui
    University of Skövde.
    Feature Sensitive Mesh Reconstruction by Normal Vector Cone Filtering2011In: PROCEEDINGS OF THE ASME INTERNATIONAL DESIGN ENGINEERING TECHNICAL CONFERENCES AND COMPUTERS AND INFORMATION IN ENGINEERING CONFERENCE, 2011, VOL 2, PTS A AND B, ASME Press, 2011, p. 619-628Conference paper (Refereed)
    Abstract [en]

    Automatic and reliable reconstruction of sharp features remains an open research issue in triangle mesh surface reconstruction. This paper presents a new feature sensitive mesh reconstruction method based on dependable neighborhood geometric information per input point. Such information is derived from the matching result of the local umbrella mesh constructed at each point. The proposed algorithm is different from the existing post-processing algorithms. The proposed algorithm reconstructs the triangle mesh via an integrated and progressive reconstruction process and features a unified multi-level inheritance priority queuing mechanism to prioritize the inclusion of each candidate triangle. A novel flatness sensitive filter, referred to as the normal vector cone filter, is introduced in this work and used to reliably reconstruct sharp features. In addition, the proposed algorithm aims to reconstruct a watertight manifold triangle mesh that passes through the complete original point set without point addition and removal. The algorithm has been implemented and validated using publicly available point cloud data sets. Compared to the original object geometry, it is seen that the reconstructed triangle meshes preserve the sharp features well and only contain minor shape deviations.

  • 160. Mao, Jin
    et al.
    Xu, Xun
    Wang, Lihui
    University of Skövde.
    Newman, Stephen
    A Statistic Review of Computer-Aided Process Planning Research2010Conference paper (Refereed)
    Abstract [en]

    Since the late 1970’s, computer-aided process planning (CAPP) has attracted a large amount of research interest, which has led to a huge volume of literature published on this subject. The literature encompasses both reviews and research articles. The review articles are mostly technologically oriented. This paper takes a different angle to look back the CAPP research, that is, a statistic approach. The paper analyses the journals that have been publishing CAPP research works. The concept of “Subject Strength” of a journal is introduced and used to gauge the level of focus of a journal on a particular research subject/domain, i.e. CAPP. Discussions about the recent CAPP research works are presented in different categories as they fall in. The term “Technology Impact Factor (TIF)” is introduced to assess the level of impact of a particular technology, in terms of citation counts. All discussions and analyses are carried out based on the data gathered from the Elsevier’s Scopus abstract and citation database. Finally, a discussion on the future development is presented. The literature suggests that this is the only review article of the similar nature in the first decade of the century.

  • 161. Meng, Y.
    et al.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Wu, X. F.
    Liu, X. L.
    Ren, G. X.
    A study on energy consumption of a CNC milling machine based on cutting force model2014Conference paper (Refereed)
    Abstract [en]

    Machining operations are performed by machine tools with a large amount of energy consumed for material removal. Understanding and characterizing the energy consumption is essential to explore the potential of energy-saving in energy-efficient machining. For this purpose, this paper proposes a method for modeling energy consumption of end milling operation which is based on cutting theory. The cutting power model is verified with experiments on a CNC milling machine. According to the calculated and experimental results, it is clear that the theoretical prediction can predict the mean cutting power successfully as validated by actual measurements.

  • 162.
    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.

  • 163. Mohammed, Abdullah
    et al.
    Givehchi, Mohammad
    Wang, Lihui
    Interfacing Image Processing with Robotic Sketching2012Conference paper (Refereed)
    Abstract [en]

    In attempt to have a flexible manufacturing environment with adaptive control systems, several researchers tend to integrate vision systems into the industrial systems to achieve that objective; the majority of the research works that have been done in this perspective tend to keep this kind of integration fully automated. Along the same direction, this paper presents an approach for integrating Robotic Sketching and Path Planning with Image Processing, and it introduces at the same time the ability for operators to remotely control and monitor the processing stages. It has been accomplished using network based architecture consisting of a vision system together with a server, a client and an ABB industrial robot. The aims of this paper are: (1) to provide an example that illustrates the benefit of interfacing the image processing techniques with the industrial shop floor system, and (2) to develop a web based system that allows an operator to remotely monitor and control the stages of the application using Java based applet. Further analyses have been done for the processing times of the application; this helped us to address the problem that consumed the largest proportion of the processing time. The work that has been done in this research provides additional supervision ability for the integrated system, and it demonstrates some of the challenges and the obstacles that may face this kind of integration.

  • 164.
    Mohammed, Abdullah
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Schmidt, B.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Energy-Efficient Robot Configuration for Assembly2017In: Journal of manufacturing science and engineering, ISSN 1087-1357, E-ISSN 1528-8935, Vol. 139, no 5, article id 051007Article in journal (Refereed)
    Abstract [en]

    Optimizing the energy consumption of robot movements has been one of the main focuses for most of today's robotic simulation software. This optimization is based on minimizing a robot's joint movements. In many cases, it does not take into consideration the dynamic features. Therefore, reducing energy consumption is still a challenging task and it involves studying the robot's kinematic and dynamic models together with application requirements. This research aims to minimize the robot energy consumption during assembly. Given a trajectory and based on the inverse kinematics and dynamics of a robot, a set of attainable configurations for the robot can be determined, perused by calculating the suitable forces and torques on the joints and links of the robot. The energy consumption is then calculated for each configuration and based on the assigned trajectory. The ones with the lowest energy consumption are selected. Given that the energyefficient robot configurations lead to reduced overall energy consumption, this approach becomes instrumental and can be embedded in energy-efficient robotic assembly.

  • 165.
    Mohammed, Abdullah
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Schmidt, B.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Gao, L.
    Minimizing energy consumption for robot arm movement2014Conference paper (Refereed)
    Abstract [en]

    Robots are widely used in industry due to their efficiency and high performance. Many of them are operating in the manufacturing stage of the production line where the highest percentage of energy is consumed. Therefore, their energy consumption became a major focus for many robots manufacturers and academic research groups. Nevertheless, the optimization of that consumption is still a challenging task which requires a deep understanding of the robot's kinematic and dynamic behaviors. This paper proposes an approach to develop an optimization module using Matlab® to minimize the energy consumptions of the robot's movement. With the help of Denavit-Hartenberg notation, the approach starts first by solving the inverse kinematics of the robot to find a set of feasible joint configurations required to perform the task, solving the inverse kinematics is usually a challenging step which requires in-depth analyses of the robot. The module then solves the inverse dynamics of the robot to analyze the forces and torques applied on each joint and link in the robot. Furthermore, a calculation for the energy consumption is performed for each configuration. The final step of the process represents the optimization of the calculated configurations by choosing the one with the lowest power consumption and sends the results to the robot controller. Three case studies are used to evaluate the performance of the module. The experimental results demonstrate the developed module as a successful tool for energy efficient robot path planning. Further analyses for the results have been done by comparing them with the ones from commercial simulation software. The case studies show that the optimization of the location for the target path could reduce the energy consumption effectively.

  • 166.
    Mohammed, Abdullah
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Schmidt, Bernard
    University of Skövde.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Active collision avoidance for human–robot collaboration driven by vision sensors2016In: International journal of computer integrated manufacturing (Print), ISSN 0951-192X, E-ISSN 1362-3052, p. 1-11Article in journal (Refereed)
    Abstract [en]

    Establishing safe human–robot collaboration is an essential factor for improving efficiency and flexibility in today’s manufacturing environment. Targeting safety in human–robot collaboration, this paper reports a novel approach for effective online collision avoidance in an augmented environment, where virtual three-dimensional (3D) models of robots and real images of human operators from depth cameras are used for monitoring and collision detection. A prototype system is developed and linked to industrial robot controllers for adaptive robot control, without the need of programming by the operators. The result of collision detection reveals four safety strategies: the system can alert an operator, stop a robot, move away the robot, or modify the robot’s trajectory away from an approaching operator. These strategies can be activated based on the operator’s existence and location with respect to the robot. The case study of the research further discusses the possibility of implementing the developed method in realistic applications, for example, collaboration between robots and humans in an assembly line.

  • 167. Mohammed, Abdullah
    et al.
    Schmidt, Bernard
    Wang, Lihui
    Remote Monitoring and Controlling for Robotic Path Following Operations2012Conference paper (Refereed)
    Abstract [en]

    Controlling a robot's movement requires a prior knowledge about the needed path and configurations to accomplish the movement. The lack of this knowledge causes limitations in the robot's adaptability in dynamic environments. The objectives of this paper are: (1) to improve the ability of the robot to follow any arbitrary path defined by an operator, and (2) to provide the ability for an authorized distant operator to access the system for monitoring and controlling both the robot and the stages of the process. The system developed in this research consists of a calibrated network camera, an industrial robot and an application server. The process starts by having a sketch drown by an operator representing the paths that the robot needs to follow, then the operator can remotely take a snapshot of the paths and retrieve the contours that represent the paths; after that the system sends them to the robot controller to perform the task of path following. The results have shown that the system can perform the required task within a relatively short time and with a reasonable level of quality. This research proves that it is possible to build an adaptive robotic system that can follow efficiently any arbitrary path without the need for defining it in advance.

  • 168.
    Mohammed, Abdullah
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Schmidt, Bernard
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Liang, Gao
    Minimising Energy Consumption for Robot Arm Movement2014Conference paper (Refereed)
    Abstract [en]

    Robots are widely used in industry due to their efficiency and high performance. Many of them are operating in the manufacturing stage of the production line where the highest percentage of energy is consumed. Therefore, their energy consumption became a major focus for many robots manufacturers and academic research groups. Nevertheless, the optimisation of that consumption is still a challenging task which requires a deep understanding of the robot’s kinematic and dynamic behaviours. This paper proposes an approach to develop an optimisation module using Matlab® to minimise the energy consumptions of the robot’s movement. With the help of Denavit-Hartenberg notation, the approach starts first by solving the inverse kinematics of the robot to find a set of feasible joint configurations required to perform the task, solving the inverse kinematics is usually a challenging step which requires in-depth analyses of the robot. The module then solves the inverse dynamics of the robot to analyse the forces and torques applied on each joint and link in the robot. Furthermore, a calculation for the energy consumption is performed for each configuration. The final step of the process represents the optimisation of the calculated configurations by choosing the one with the lowest power consumption and sends the results to the robot controller. Three case studies are used to evaluate the performance of the module. The experimental results demonstrate the developed module as a successful tool for energy efficient robot path planning. Further analyses for the results have been done by comparing them with the ones from commercial simulation software. The case studies show that the optimisation of the location for the target path could reduce the energy consumption effectively.

  • 169.
    Mohammed, Abdullah
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Brainwaves driven human-robot collaborative assembly2018In: CIRP annals, ISSN 0007-8506, E-ISSN 1726-0604, Vol. 67, no 1, p. 13-16Article in journal (Refereed)
    Abstract [en]

    This paper introduces an approach to controlling an industrial robot using human brainwaves as a means of communication. The developed approach starts by establishing a set of training sessions where an operator is enquired to think about a set of defined commands for the robot and record the brain activities accordingly. The results of the training sessions are then used on the shop floor to translate the brain activities to a set of robot control commands. An industrial case study is carried out to assist the operator in coordinating a collaborative assembly task of a car engine manifold.

  • 170.
    Mohammed, Abdullah
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Vision-Based Robotic Path Following2013In: International Journal of Mechanisms and Robotic Systems, ISSN 2047-7252, Vol. 1, no 1, p. 95-111Article in journal (Refereed)
    Abstract [en]

    Most robotic manufacturing applications nowadays require tedious and expensive pre–programming of the chosen robot, each time when a new task is introduced. In order to eliminate the tedious robot programming for better productivity, this research proposes an adaptive approach that allows a robot to follow any arbitrary robot path defined by an operator. A so–developed system was designed to monitor and control the path following operation locally or remotely through an established web–based architecture, without the need of extra programming. The objective of the research is achieved by integrating an image processing module with a robotic system. The real benefits of such a system are the ability to control and monitor the stepwise processing stages, as well as to automate the whole operation to a certain level of control defined in advance. In particular, this paper introduces a prototype that can be extended to various industrial applications, such as arc welding, laser cutting and water jet cutting, which require controlling the 2D or 3D path of a robot.

  • 171.
    Mohammed, Abdullah
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Gao, R. X.
    Integrated Image Processing and Path Planning for Robotic Sketching2012In: Proceedings of the 8th CIRP Conference on Intelligent Computation in Manufacturing Engineering, 2012Conference paper (Refereed)
  • 172. Moriwaki, T.
    et al.
    Sugimura, N.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    A Modelling System for Finite Element Analysis of Machine Products1993In: Transactions of the North American Manufacturing Research Institution of SME, ISSN 1047-3025, Vol. 21, p. 383-390Article in journal (Refereed)
  • 173. Moriwaki, T.
    et al.
    Sugimura, N.
    Wang, Lihui
    A Study on Thermal Analysis for Machine Tools with Relative Motions1993Conference paper (Refereed)
  • 174. Moriwaki, T.
    et al.
    Sugimura, N.
    Wang, Lihui
    Development of an Integrated CAD/CAE System for Machine Tool Design1993In: Integrated Manufacturing Systems of JSPE, p. 81-94Article in journal (Refereed)
  • 175. Moriwaki, T.
    et al.
    Sugimura, N.
    Wang, Lihui
    Development of Modelling System for CAD/CAE of Machine Tools (Part-1: Automatic Mesh Adjustment of FEM Model for Moving Parts)1993In: International journal of the Japan Society for Precision Engineering, ISSN 0916-782X, Vol. 59, no 2, p. 233-238Article in journal (Refereed)
  • 176. Moriwaki, T.
    et al.
    Sugimura, N.
    Wang, Lihui
    Development of Modelling System for CAD/CAE of Machine Tools (Part-2: Application of Thermal Analysis for Moving Parts)1994In: International journal of the Japan Society for Precision Engineering, ISSN 0916-782X, Vol. 60, no 7, p. 959-963Article in journal (Refereed)
  • 177. Moriwaki, T.
    et al.
    Sugimura, N.
    Wang, Lihui
    Modelling System for CAD/CAE of Machine Tools (1st Report, Concept and Approach to the System)1992Conference paper (Refereed)
  • 178. Moriwaki, T.
    et al.
    Sugimura, N.
    Wang, Lihui
    Modelling System for CAD/CAE of Machine Tools (2nd Report, Automatic Generation of FEM Models)1992Conference paper (Refereed)
  • 179. Moriwaki, T.
    et al.
    Sugimura, N.
    Wang, Lihui
    Modelling System for CAD/CAE of Machine Tools (3rd Report, Integrated Management of Finite Element Nodal Information)1992Conference paper (Refereed)
  • 180. Moriwaki, T.
    et al.
    Sugimura, N.
    Wang, Lihui
    Study on Modelling Methods for Kinematic Analysis of Machine Tools1991In: Integrated Manufacturing Systems of JSPE, p. 69-78Article in journal (Refereed)
  • 181. Moriwaki, T.
    et al.
    Sugimura, N.
    Wang, Lihui
    Araki, Y.
    Modelling System for CAD/CAE of Machine Tools (4th Report, Application to Thermal Analysis with Relative Motions)1993In: Proceedings of 1993 Spring Annual Meeting of Japan Society for Precision Engineering, 1993, p. 39-40Conference paper (Refereed)
  • 182. Moriwaki, T.
    et al.
    Wang, Lihui
    Study on Thermal Behaviour of Machine Tool Elements across Movable Joints Under Operating States1995Conference paper (Refereed)
  • 183. Moriwaki, T.
    et al.
    Wang, Lihui
    Kuroda, N.
    Study on Thermal Deformation of Machine Tools1994Conference paper (Refereed)
  • 184. Moriwaki, T.
    et al.
    Wang, Lihui
    Kuroda, N.
    Thermal Analysis of Machine Elements with Relative Motions1994Conference paper (Refereed)
  • 185. Mourtzis, D.
    et al.
    Vlachou, E.
    Xanthopoulos, N.
    Givehchi, Mohammad
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Cloud-based adaptive process planning considering availability and capabilities of machine tools2016In: Journal of manufacturing systems, ISSN 0278-6125, E-ISSN 1878-6642, Vol. 39, p. 1-8Article in journal (Refereed)
    Abstract [en]

    Disturbances on manufacturing shop-floors and the increasing number of product variants necessitate adaptive and flexible process planning methods. This paper proposes a service-oriented Cloud-based software framework comprising two services. The first service generates non-linear process plans using event-driven function blocks and a genetic algorithm. The second service, gathers data from shop-floor machine tools through sensors, input from operators, and machine schedules. An information fusion technique processes the monitoring data in order to feed the process planning service with the status, specifications, and availability time windows of machine tools. The methodology is validated in a case study of a machining SME.

  • 186. Newman, S. T.
    et al.
    Ali, L.
    Brail, A.
    Brecher, C.
    Klemm, P.
    Liu, R.
    Nassehi, A.
    Nguyen, V. K.
    Proctor, F.
    Rosso, R. S. U.
    Stroud, I.
    Suh, S. H.
    Vitr, M.
    Wang, Lihui
    Xu, X. W.
    The Evolution of CNC Technology from Automated Manufacture to Global Interoperable Manufacturing2007Conference paper (Refereed)
  • 187. Newman, S.T.
    et al.
    Nassehi, A.
    Xu, Xun
    Rosso Jr., R.S.U.
    Wang, Lihui
    Integrated Manufacturing Technologies Institute, NRC, London, Ontario, Canada.
    Yusof, Y.
    Ali, L.
    Liu, R.
    Zheng, L.
    Kumar, S.
    Vichare, P.
    Dhokia, V.
    Strategic Advantages of Interoperability for Global Manufacturing Using CNC Technology2008In: Robotics and Computer-Integrated Manufacturing, ISSN 0736-5845, E-ISSN 1879-2537, Vol. 24, no 6, p. 699-708Article in journal (Refereed)
    Abstract [en]

    In the domain of manufacturing, computer numerically controllers (CNC) technology is a major contributor to the production capacity of the enterprises. The advances in CNC technology coupled with enhancements ill computing systems have provided the basis to re-examine the way in which computer-aided systems (CAx) call be used to enable global manufacturing. Interoperability of the various components of the CAx chain is therefore a major prerequisite for manufacturing enterprises for becoming strategically agile and consequently globally competitive. Being interoperable, resources call be utilized interchangeably in a plug-and-produce manner. Over the last 8 years the eminence of a STEP standard for machining entitled STEP-NC (numerical control) has become a well-known vehicle for research to improve the level of information availability at the CNC machine too]. Ill this paper, the authors introduce the background to the evolution of CNC manufacturing over the last 50 years and the Current standards available for programming. A review of the literature in interoperable CNC Manufacturing is then provided relating to Milling, turn-mill and other NC processes. The major part of the paper provides a strategic view of]low interoperability call be implemented across the CAx chain with a range of standards used to regulate the flow of information. Finally, the paper Outlines the advantages and major issues for future developments in interoperability, identifying future key requirements and limiting factors.

  • 188. Newman, Stephen
    et al.
    Xu, X.W.
    Rosso Jr., R.S.U.
    Wang, Lihui
    Yusof, Y.
    Ali, L.
    Liu, R.
    Zheng, L.
    Kumar, S.
    Vichare, P.
    Dhokia, V.
    Interoperable CNC for Global Manufacturing2007Conference paper (Refereed)
  • 189. Peng, Tao
    et al.
    Xu, Xun
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    A novel energy demand modelling approach for CNC machining based on function blocks2014In: Journal of manufacturing systems, ISSN 0278-6125, E-ISSN 1878-6642, Vol. 33, no 1, p. 196-208Article in journal (Refereed)
    Abstract [en]

    Energy efficiency remains one of the major issues in the machining domain. Today's machining systems are confronted with a number of new challenges, such as turbulent product demand and variations in production resources. Rapid and flexible energy modelling in a distributed and collaborative machining environment emerges as a new research area. Energy demand models in such an environment need to be practical, accurate, effective, scalable and reusable. Energy analysis and optimisation cannot be carried out once for all at the beginning. Instead, it is an on-going process. In this paper, the function block technique, i.e. IEC 61499, is used for the development of energy demand models as it brings advantages such as modularity, encapsulation, extensibility and reusability. A brief review on energy modelling and research on function blocks are given in the first part. A novel energy demand modelling approach based on function blocks is then proposed and elaborated. Three types of function blocks have been developed, i.e. machine tool dependent function blocks, state transition function blocks, and service interface function blocks. The first type, as the fundamental building blocks, is divided into two sub-types, machine component function block and machining state function block. Two case studies, based on a small 3-axis milling machine and an industrial production line respectively, are presented to demonstrate the possible applications using the function block-based model. Comprehensive discussions are given thereafter, including a pilot application of a distributed process planning system and a unique energy evaluation scheme. A confidence level associated energy rating system is proposed as the first step to turn energy consumption figures into useful indicators. The energy demand model based on function blocks developed here enhances the energy modelling and their practical implementations.

  • 190. Ren, Lei
    et al.
    Zhang, Lin
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Production Systems.
    Tao, Fei
    Chai, Xudong
    Cloud manufacturing: key characteristics and applications2017In: International journal of computer integrated manufacturing (Print), ISSN 0951-192X, E-ISSN 1362-3052, Vol. 30, no 6, p. 501-515Article in journal (Refereed)
    Abstract [en]

    Cloud manufacturing is emerging as a new manufacturing paradigm as well as an integrated technology, which is promising in transforming today's manufacturing industry towards service-oriented, highly collaborative and innovative manufacturing in the future. In order to better understand cloud manufacturing, this paper provides a critical review of relevant concepts and ideas in cloud computing as well as advanced manufacturing technologies that contribute to the evolution of cloud manufacturing. The key characteristics of cloud manufacturing are also presented in order to clarify the cloud manufacturing concept. Furthermore, a four-process structure is proposed to describe the typical scenario in cloud manufacturing, hoping to provide a theoretical reference for practical applications. Finally, an application case of a private cloud manufacturing system for a conglomerate is presented.

  • 191. Sandberg, Ulf
    et al.
    Schmidt, Bernard
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Management of Factory and Maintenance Information for Multiple Production and Product Life-Cycle Phases2014Conference paper (Refereed)
    Abstract [en]

    Maintenance is crucial for future manufacturing systems. An extended local knowledge is essential to increase precision and efficiency, but also for improvements of the maintained object itself. Approaches exist that closes the loop from end-user to vendor, but intra loops are not so well developed.

    This article discusses ways to interconnect and manage data and knowledge flow between work processes in user and vendor life-cycles. It aims to inspire improvements in existing approaches, closer connections between producer and customer, between users, and improved quality of maintenance work via factory-, company-, or group-wide data and knowledge about similar types of equipment.

  • 192. Schmidt, B.
    et al.
    Gandhi, K.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering. School of Engineering Science, University of Skövde, PO Box 408, Skövde, 541 28, Sweden.
    Diagnosis of machine tools: Assessment based on double ball-bar measurements from a population of similar machines2018In: 51st CIRP Conference on Manufacturing Systems, Elsevier, 2018, Vol. 72, p. 1327-1332Conference paper (Refereed)
    Abstract [en]

    The presented work is toward population-based predictive maintenance of manufacturing equipment with consideration of the automatic selection of signals and processing methods. This paper describes an analysis performed on double ball-bar measurement from a population of similar machine tools. The analysis is performed after aggregation of information from Computerised Maintenance Management System, Supervisory Control and Data Acquisition, NC-code and Condition Monitoring from a time span of 4 years. Economic evaluation is performed with use of Monte Carlo simulation based on data from real manufacturing setup.

  • 193. Schmidt, B.
    et al.
    Mohammed, Abdullah
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Minimising Energy Consumption for Robot Arm Movement2013Conference paper (Refereed)
  • 194. Schmidt, B.
    et al.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering. Virtual Systems Research Centre, University of Skövde, Sweden .
    Contact-less and programming-less human-robot collaboration2013In: Forty Sixth CIRP Conference on Manufacturing Systems 2013, 2013, p. 545-550Conference paper (Refereed)
    Abstract [en]

    In today's manufacturing environment, safe human-robot collaboration is of paramount importance, to improve efficiency and flexibility. Targeting the safety issue, this paper presents an approach for human-robot collaboration in a shared workplace in close proximity, where real data driven 3D model of a robot and multiple depth images of the workplace are used for monitoring and decision-making to perform a task. The strategy for robot control depends on the current task and the information about the operator's presence and position. A case study of assembly is carried out in a robotic assembly cell with human collaboration. The results show that this approach can be applied in real-world applications such as human-robot collaborative assembly with human operators safeguarded at all time.

  • 195. Schmidt, B.
    et al.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Predictive Maintenance of Machine Tool Linear Axes: A Case from Manufacturing Industry2018In: Procedia Manufacturing, Elsevier B.V. , 2018, p. 118-125Conference paper (Refereed)
    Abstract [en]

    In sustainable manufacturing, the proper maintenance is crucial to minimise the negative environmental impact. In the context of Cloud Manufacturing, Internet of Things and Big Data, amount of available information is not an issue, the problem is to obtain the relevant information and process them in a useful way. In this paper a maintenance decision support system is presented that utilises information from multiple sources and of a different kind. The key elements of the proposed approach are processing and machine learning method evaluation and selection, as well as estimation of long-term key performance indicators (KPIs) such as a ratio of unplanned breakdowns or a cost of maintenance approach. Presented framework is applied to machine tool linear axes. Statistical models of failures and Condition Based Maintenance (CBM) are built based on data from a population of 29 similar machines from the period of over 4 years and with use of proposed processing approach. Those models are used in simulation to estimate the long-term effect on selected KPIs for different strategies. Simple CBM approach allows, in the considered case, a cost reduction of 40% with the number of breakdowns reduced 6 times in respect to an optimal time-based approach.

  • 196. Schmidt, Bernard
    et al.
    Galar, Diego
    Wang, Lihui
    University of Skövde, School of Engineering Science University of Skövde, The Virtual Systems Research Centre. KTH.
    Asset Management Evolution: from Taxonomies toward Ontologies2015Conference paper (Refereed)
    Abstract [en]

    This paper addresses the evolution that can be observed in Asset Management in modelling approach. Most traditional Condition Monitoring systems use hierarchical representations of monitored the integration of data from disparate source toward context awareness and Big Data utilization there is a need to include and model more complicated dependencies than hierarchical. Ontology based modelling is gaining recently on popularity in the domain of Condition Monitoring and Asset Management.

  • 197. Schmidt, Bernard
    et al.
    Wang, Lihui
    Automatic Robot Calibration via a Global-Local Camera System2012Conference paper (Refereed)
    Abstract [en]

    In a human-robot collaborative manufacturing application where working object can be placed in an arbitrary position, there is a need to calibrate the actual position of the work object. This paper presents an approach for automatic calibration in flexible robotic systems. It consists of two subsystems: a global positioning system based on fixed cameras mounted around robotic workspace, and a local positioning system based on the camera mounted on the robot arm. The aim of the global positioning is to detect work object in working area and roughly estimate the position, whereas the local positioning is to define the object frame according to the 3D position and orientation of the work object with higher accuracy. For object detection and localization, coded visual markers have been utilized. For each object, several markers have been used to increase the robustness and accuracy of localization and calibration procedure. This approach can be used in robotic welding or assembly applications.

  • 198. Schmidt, Bernard
    et al.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Automatic work objects calibration via a global-local camera system2014In: Robotics and Computer-Integrated Manufacturing, ISSN 0736-5845, E-ISSN 1879-2537, Vol. 30, no 6, p. 678-683Article in journal (Refereed)
    Abstract [en]

    In a human robot collaborative manufacturing application where a work object can be placed in an arbitrary position, there is a need to calibrate the actual position of the work object. This paper presents an approach for automatic work-object calibration in flexible robotic systems. The approach consists of two modules: a global positioning module based on fixed cameras mounted around robotic workspace, and a local positioning module based on the camera mounted on the robot arm. The aim of the global positioning is to detect the work object in the working area and roughly estimate its position, whereas the local positioning is to define an object frame according to the 3D position and orientation of the work object with higher accuracy. For object detection and localization, coded visual markers are utilized. For each object, several markers are used to increase the robustness and accuracy of the localization and calibration procedure. This approach can be used in robotic welding or assembly applications.

  • 199. Schmidt, Bernard
    et al.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering. University of Skövde, Sweden.
    Depth camera based collision avoidance via active robot control2014In: Journal of manufacturing systems, ISSN 0278-6125, E-ISSN 1878-6642, Vol. 33, no 4, p. 711-718Article in journal (Refereed)
    Abstract [en]

    A new type of depth cameras can improve the effectiveness,of safety monitoring in human-robot collaborative environment. Especially on today's manufacturing shop floors, safe human-robot collaboration is of paramount importance for enhanced work efficiency, flexibility, and overall productivity. Within this context, this paper presents a depth camera based approach for cost-effective real-time safety monitoring of a human-robot collaborative assembly cell. The approach is further demonstrated in adaptive robot control. Stationary and known objects are first removed from the scene for efficient detection of obstacles in a monitored area. The collision detection is processed between a virtual model driven by real sensors, and 3D point cloud data of obstacles to allow different safety scenarios. The results show that this approach can be applied to real-time work cell monitoring.

  • 200. Schmidt, Björn
    et al.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Production Systems.
    Cloud-enhanced predictive maintenance2018In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 99, no 1-4, p. 5-13Article 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.

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