| 1. |
- Agmell, Mathias, et al.
(författare)
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The Influence the Uncut Chip Thickness has on the Stagnation Point in Orthogonal Cutting
- 2017
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Ingår i: 16th CIRP Conference on Modelling of Machining Operations (16th CIRP CMMO). - : Elsevier BV. - 2212-8271. - 9781510842762 ; 58, s. 13-18
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Konferensbidrag (refereegranskat)abstract
- The effect of cutting data on the stagnation zone of a machining operation is of great interest since it governs the material flow around the cutting edge. The material flow has a significant influence on the mechanical properties of the machined surface. This paper presents a numerical model that is able to determine the effect that the uncut chip thickness has on the stagnation zone and the connection between the stagnation zone and the deformation layer in the machined subsurface.
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| 2. |
- Gutnichenko, O., et al.
(författare)
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Modeling of Force Build-up Process and Optimization of Tool Geometry when Intermittent Turning
- 2017
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Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271 .- 2212-8271. - 9781510842762 ; 58, s. 393-398
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Tidskriftsartikel (refereegranskat)abstract
- Intermittent turning the slotted workpieces is always accompanied with a high impact load of the machine tool during the entry phase of the cutting edge. The process leads to a strong dynamic response of the system and results in vibrations arose and potential tool life and surface finish issues. The present study addresses the modeling of cutting force build-up process with further optimization of cutting edge geometry where tooltip overshoot during the tool entry is selected as an objective function. The model takes into consideration the interaction between three units of the machine tool such as a tool, toolpost, and workpiece as well as an influence of the process on the system's dynamics.
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| 3. |
- Kryzhanivskyy, V., et al.
(författare)
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Computational and Experimental Inverse Problem Approach for Determination of Time Dependency of Heat Flux in Metal Cutting
- 2017
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Ingår i: 16th CIRP Conference on Modelling of Machining Operations (16th CIRP CMMO). - : Elsevier BV. - 2212-8271. - 9781510842762 ; 58, s. 122-127
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Konferensbidrag (refereegranskat)abstract
- This study develops the method for solution of inverse heat conduction problem applied to metal cutting. The proposed method operates with a selection procedure involving iterative solutions of heat forward problem. In such formulation, it allows avoiding difficulties associated with ill-posed inverse problems inherent to conventional formulations. Inverse heat problem was transformed into constrained optimization problem via objective function which metrizes the difference between FE and experimental data. Specially designed solid HSS cutting tool with embedded thermocouples was manufactured. The method was validated for the case of orthogonal machining of 6061 aluminum alloy. The numerical simulations were performed with the help of COMSOL Multiphysics and MATLAB scripts. Heat flux exhibits descending trend over the time of the cutting test and closely follows hyperbola function behavior with the average value of q = 4.6 MW/m2.
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| 4. |
- Mohammed, Abdullah, et al.
(författare)
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Minimizing energy consumption for robot arm movement
- 2014
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Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271 .- 2212-8271. ; 25, s. 400-405
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Konferensbidrag (refereegranskat)abstract
- 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.
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| 5. |
- Persson, Henrik, et al.
(författare)
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Experimental and Numerical Investigation of Burr Formation in Intermittent Turning of AISI 4140
- 2017
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Ingår i: 16th CIRP Conference on Modelling of Machining Operations (16th CIRP CMMO). - : Elsevier BV. - 2212-8271. - 9781510842762 ; 58, s. 37-42
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Konferensbidrag (refereegranskat)abstract
- Burr formation is a problematic aspect in the machining of ductile metals. Understanding the formation mechanism and being able to model the plastic workpiece behavior during tool exits is key to burr minimization. A 3D finite element model is used to simulate burr formation during the exit phase of intermittent turning of AISI 4140, using a nose radiused insert. The model is validated by experimental results of dynamic force measurement and analysis of the burrs produced. The exit burr height obtained via simulation closely corresponds to the experimentally obtained values.
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| 6. |
- Stenberg, Niclas, 1964-, et al.
(författare)
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Numerical Modelling of Turning to Find Residual Stresses
- 2013
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Ingår i: Procedia CIRP. - : Elsevier. - 2212-8271. ; , s. 258-264
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Konferensbidrag (refereegranskat)abstract
- In this study a thermo-mechanical numerical simulation of the machining operation is presented. The purpose of the simulations is to obtain the residual stresses. The FE-simulations are compared to measurements of a machined axis. The reason for this work is to see if residual stress calculations have reached a level where it could be performed on a daily basis. Therefore, the simulations were performed with the software package DEFORM which has a re-mesh function that, for practical reasons, is necessary when forming chips. The large deformations will make the FE-analysis to costly otherwise.The work includes a parametric study of machining parameters in order to foresee the impact on the residual stresses. These simulations have also been compared to measurements.The FE-simulations has proved to predict the residual stresses in principle. However, even though the stress gradient in the vicinity of the surface is captured the exact stress level on the surface could not be foreseen. This effect was attributed to the re-mesh function. The parametric study showed that residual stresses can be foreseen, but not all the way up to the surface. Simulated results are only valid from approx 0.05mm-0.1mm below the surface. However, even with this restriction the FE-analysis can be used for optimising the cutting parameters with respect to residual stresses.
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| 7. |
- Abdoli, Shiva, et al.
(författare)
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Analyzing the Environmental Consequences of Production Processes from a System of Systems Perspective : A Case of Gear Manufacturing in the Automotive Industry
- 2021
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Ingår i: The 28th CIRP Conference on Life Cycle Engineering, March 10 – 12, 2021, Jaipur, India. - : Elsevier BV. - 2212-8271. ; 98, s. 376-381
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Konferensbidrag (refereegranskat)abstract
- Many research studies have been done to investigate different aspects of environmental challenges. In the product development context, there have been attempts to reduce the environmental impacts of associated activities including the production processes themselves. As a result, various technological improvements have been made and new production processes e.g. powder metallurgy technologies have been introduced that may demonstrate a lower environmental footprint compared to conventional processes e.g. cutting machining technologies. However, a production process with a lower environmental impact may lead to reducing the quality/performance attributes of the produced parts (gear) and probably of final products (transmission box). Therefore, the efforts intended to produce more sustainable products by using production processes with less environmental footprints may lead to some unintended consequences such as increased maintenance requirements and/or demand. This is a rebound effect from a system of systems (SoS) perspective. This paper aims to analyze the impacts of more environmentally friendly production processes on the total environmental impact associated with a product given they may have a negative impact on a part/product's quality and performance or usage. This paper introduces a methodological approach to analyze the environmental sustainability of a production process at a SoS level. This is done by including the entire supply chain of a product-system and its interacting systems by using the results of the attributional/consequential life cycle assessment (LCA) method. The approach validity approach is demonstrated in the case of gear manufacturing in the automotive industry.
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| 8. |
- Abdullah Asif, Farazee Mohammad, 1980-, et al.
(författare)
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A practical ICT framework for transition to circular manufacturing systems
- 2018
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Ingår i: Procedia CIRP. - : Elsevier. - 2212-8271. ; , s. 598-602
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Konferensbidrag (refereegranskat)abstract
- The transition towards a circular economy has become important. Manufacturing industry being a major stakeholder in this transition has started exploring the potential of this transition and challenges in implementation. Ambitious companies such as Gorenje d.d. has taken the circular economy transition seriously and aims to become a pioneer in implementing circular manufacturing systems. One vital step in this transition is the business model shift from the linear (sales model) to a circular model such as 'product as a service'. This brings new challenges to Original Equipment Manufacturers (OEMs) that have never been experienced in their conventional businesses. One of the challenges is to establish an information communication and technology (ICT) infrastructure that enables information management and sharing as well as establishes a real-time communication between relevant stakeholders. Outlining such an ICT infrastructure is the objective of this paper.
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| 9. |
- Adamson, Göran, 1958-, et al.
(författare)
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A Cloud Service Control Approach for Distributed and Adaptive Equipment Control in Cloud Environments
- 2016
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Ingår i: Procedia CIRP. - : Elsevier. - 2212-8271 .- 2212-8271. ; 41, s. 644-649, s. 644-649
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Tidskriftsartikel (refereegranskat)abstract
- A developing trend within the manufacturing shop-floor domain is the move of manufacturing activities into cloud environments, as scalable, on-demand and pay-per-usage cloud services. This will radically change traditional manufacturing, as borderless, distributed and collaborative manufacturing missions between volatile, best suited groups of partners will impose a multitude of advantages. The evolving Cloud Manufacturing (CM) paradigm will enable this new manufacturing concept, and on-going research has described many of its anticipated core virtues and enabling technologies. However, a major key enabling technology within CM which has not yet been fully addressed is the dynamic and distributed planning, control and execution of scattered and cooperating shop-floor equipment, completing joint manufacturing tasks.In this paper, the technological perspective for a cloud service-based control approach is described, and how it could be implemented. Existing manufacturing resources, such as soft, hard and capability resources, can be packaged as cloud services, and combined to create different levels of equipment or manufacturing control, ranging from low-level control of single machines or devices (e.g. Robot Control-as-a-Service), up to the execution of high level multi-process manufacturing tasks (e.g. Manufacturing-as-a-Service). A multi-layer control approach, featuring adaptive decision-making for both global and local environmental conditions, is proposed. This is realized through the use of a network of intelligent and distributable decision modules such as event-driven Function Blocks, enabling run-time manufacturing activities to be performed according to actual manufacturing conditions. The control system’s integration to the CM cloud service management functionality is also described.
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| 10. |
- Agic, Adnan, 1967-, et al.
(författare)
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Influence of cutting edge geometry on force build-up process in intermittent turning
- 2016
-
Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271 .- 2212-8271. ; 46, s. 364-367
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Tidskriftsartikel (refereegranskat)abstract
- In the intermittent turning and milling processes, during the entry phase the cutting edges are subjected to high impact loads that can give rise to dynamical and strength issues which in general cause tool life reduction. In this study the effect of geometrical features of the cutting tool on the force generation during the entry phase is investigated. Cutting forces are measured by a stiff dynamometer at a high sampling frequency. In addition, the chip load area is analyzed and related to the measured cutting force. The results show that micro-geometrical features, in particular the protection chamfer, significantly affect the force generation during the entry phase.
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