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1.	Mohammed, Abdullah, et al. (författare) Minimizing energy consumption for robot arm movement 2014 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271 .- 2212-8271. ; 25, s. 400-405 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.
2.	Stenberg, Niclas, 1964-, et al. (författare) Numerical Modelling of Turning to Find Residual Stresses 2013 Ingår i: Procedia CIRP. - : Elsevier. - 2212-8271. ; , s. 258-264 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.
3.	Agmell, Mathias, et al. (författare) The link between plasticity parameters and process parameters in orthogonal cutting 2013 Ingår i: 14th CIRP Conference on Modeling of Machining Operations (CIRP CMMO). - : Elsevier BV. - 2212-8271. ; 8, s. 224-229 Konferensbidrag (refereegranskat)abstract In the present study the plasticity parameters in the Johnson Cook plasticity model are determined on the basis of process parameters in orthogonal cutting by use of inverse analysis. Previously established links between material parameters and process parameters in the cutting process such as chip thickness ratio, cutting forces, temperatures, deformation zones, is used serve as a starting point in the inverse analysis. The material AISI 4140 is simulated using the model employed in [1], the Johnson Cook parameters being changed within an interval of ±30 %. The inverse analysis is performed using a Kalman filter. The material model for the reference point is validated on the basis of the experimental results in [1], the model being shown to predict the process parameters with a high level of accuracy. The attempt is made to establish a link for materials having cutting process characteristics that are similar between certain process parameters and the Johnson Cook parameters in order to be able to predict the input parameters to FEM models using experimental data from a cutting process.
4.	Anderberg, Staffan, 1981-, et al. (författare) Process planning for cnc machining of swedish subcontractors : A web survey 2014 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271 .- 2212-8271. ; 17, s. 732-737 Tidskriftsartikel (refereegranskat)abstract Process planning of CNC machining is critical to ensure cost, time and quality parameters of manufacturing operations. At the heart of process planning is, typically the process planner, who must make a multitude of decisions regarding machines, cutting strategies, tools and process parameters etc. Today there are a number of different tools and methods available to aid the process planner. This paper explores today’s industrial use of some of these aids and outlinespotential underlying reasons for the current state. The empirical data is based on a questionnaire survey of Swedish CNC machining sub-contractors. The main conclusion is that despite a long history of development of various aids (CAD/CAM, PLM standards etc.) there is still a large proportion of the industry, which has not yet adopted these aids. By the responding companies 32% do not use any CAM system and only 2% use a PLM system. On the other side of the spectrum is a group of 25% that uses CAM in 75% or more of their planned products. The learning from this survey can be used to better understand the industrial needs and focus research and development efforts.
5.	Andersson, Frida, et al. (författare) Design for Manufacturing of Composite Structures for Commercial Aircraft : The Development of a DFM strategy at SAAB Aerostructures 2014 Ingår i: Procedia CIRP. - : Elsevier. - 2212-8271. ; 17, s. 362-367 Tidskriftsartikel (refereegranskat)abstract Within the aircraft industry, the use of composite materials such as carbon fiber reinforced plastics (CFRPs) is steadily increasing, especially in structural parts. Manufacturability needs to be considered in aircraft design to ensure a cost-effective manufacturing process. The aim of this paper is to describe the development of a new strategy for how SAAB Aerostructures addressing manufacturability issues during the development of airframe composite structures. Through literature review, benchmarking and company interviews, a design for manufacturing (DFM) strategy was developed. The strategy ensures that the important factors for successful DEM management are implemented on strategic, tactical and operational levels that contribute to a more cost-efficient product development process and aircraft design.
6.	Beno, Tomas, et al. (författare) Measurement of cutting edge temperature in drilling 2012 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271 .- 2212-8271. ; 3, s. 531-536 Tidskriftsartikel (refereegranskat)abstract In this paper a methodology is described to conduct temperature measurement on the cutting edges and the clearance faces on twist drills using a fibre optic two color pyrometer. Two measuring positions of the fibre were used in order to determine the temperature at two different locations, centre and outer corner of the drill. The measurements were carried out on a stationary work piece and a rotating drill. The work piece materials ranged from tool steel, aged Inconel 718, Ti6-4 to carbon epoxy fibre composite. All experiments were conducted in dry machining conditions.© 2012 The Authors.
7.	Björkenstam, Staffan C, 1981, et al. (författare) Efficient sequencing of industrial robots through optimal control 2014 Ingår i: 5th CIRP Conference on Assembly Technologies and Systems, November 13-14, 2014, Dresden, Germany. - : Elsevier BV. - 2212-8271. ; 23:C, s. 194-199 Konferensbidrag (refereegranskat)abstract In a production plant for complex assembled products there could be up to several hundred robots used for handling and joining operations. Thus, improvements in robot motion can have a huge impact on equipment utilization and energy consumption. By combining recent algorithms for collision free numerical optimal control and for optimal sequencing, we are able to cut down on energy consumption without sacrificing cycle time. The algorithm has been successfully applied to several industrial cases demonstrating that the proposed method can be used effectively in practical applications to find fast and energy efficient solutions.
8.	Bushlya, Volodymyr, et al. (författare) Effect of Cutting Conditions on Machinability of Superalloy Inconel 718 During High Speed Turning with Coated and Uncoated PCBN Tools 2012 Ingår i: 45th CIRP Conference on Manufacturing Systems 2012. - : Elsevier BV. - 2212-8271. - 9781627485128 ; 3, s. 370-375 Konferensbidrag (refereegranskat)abstract Inconel 718, an efficient superalloy for energy and aerospace applications, is currently machined with cemented carbide tools at low speed (vc≈60 m/min) due to its unfavorable mechanical and thermal properties. The article presents results of superalloy machinability study with uncoated and coated PCBN tools aiming on increased speed and efficiency. Aspects of tool life, tool wear and surface integrity were studied. It was found that protective function of the coating, increasing tool life up to 20%, is limited to low cutting speed range. EDX and AFM analyses suggested dominance of chemical and abrasive wear mechanisms. Residual stress analysis has shown advantageous compressive surface stresses.
9.	Carlson, Johan, 1972, et al. (författare) Minimizing Dimensional Variation and Robot Traveling Time in Welding Stations 2014 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 23:C, s. 77-82 Konferensbidrag (refereegranskat)abstract Complex assembled products as an automotive car body consist of about 300 sheet metal parts joined by up to 4000 spot welds. In the body factory, there are several hundred robots organized into lines of welding stations. The distribution of welds between robots and the welding sequences have a significant influence on both dimensional quality and throughput. Therefore, this paper proposes a novel method for quality and throughput optimization based on a systematic search algorithm which exploits properties of the welding process. It uses approximated lower bounds to speed up the search and to estimate the quality of the solution. The method is successfully tested on reference assemblies, including detailed fixtures, welding robots and guns.
10.	Cedergren, Stefan, 1982, et al. (författare) On the Influence of Work Material Microstructure on Chip Formation, Cutting Forces and Acoustic Emission when Machining Ti-6Al-4V 2013 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 12, s. 55-60 Konferensbidrag (refereegranskat)abstract The influence of heat treatment of work material on chip formation, when machining Ti-6Al-4V, was studied through microstructural investigation of chips, as well as response on cutting forces and acoustic emission. Three different microstructures were investigated; equiaxed, bimodal and Widmanstätten. It is well known that machining of titanium produces shear localized chips at all industrially practical cutting speeds and feed rates, however there is also a transition from aperiodic to periodic sawtooth chip formation. The feed rate was varied at constant cutting speed to study this transition from aperiodic to periodic saw-tooth chips in the three microstructures. Face turning cutting tests were used when sensor signals were collected. The results from this investigation stress the importance to consider work material microstructure when studying the chip formation process, and its impact on cutting forces and acoustic emission, when machining Ti-6Al-4V.
11.	Chen, Ling, et al. (författare) Modeling effect of surface roughness on nanoindentation tests 2013 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 8, s. 334-339 Konferensbidrag (refereegranskat)abstract Surface roughness is a commonly used criterion for characterization of surface quality in a machining operation. In the study of micro-scale mechanical properties of machined surface and cutting tool with nanoindentation, prefect surface finish on the test specimen is often required for the reliable result. However, the prefect surface finish is often difficult to obtain from the machining operation due to the limitation of the cutting tool geometry and machining dynamics. In presented paper, the effect of surface roughness on nanoindentation measurement was investigated by using finite element method. A 3D finite element model with three levels of surface roughness was developed to simulate the load-displacement indentation process with a Berkovich indenter. The material used in the simulation is AISI 316L stainless steel and it was modeled as an elastic-plastic von Misses material. Three levels of surface roughness, Ra, are used in the simulation, including 2 nm, 20 nm and 37 nm. The mechanical properties were calculated by combined simulation with the Oliver-Pharr method. The hardness and reduced modulus from the simulation was found to decrease with an increase of roughness. The scatter of load-depth curves and deviation of hardness and reduced modulus are affected by the changing of roughness. The height of pile-up was little affected by the surface roughness from the simulation. Combined effect of indenter tip radius and surface roughness was also investigated.
12.	Delfs, Niclas, et al. (författare) Automatic Creation of Manikin Motions Affected by Cable Forces 2014 Ingår i: Procedia CIRP:CIRP Conference on Assembly Technologies and Systems, CATS 2014; Dresden; Germany; 12 May 2014 through 14 May 2014. - : Elsevier BV. - 2212-8271. ; 23, s. 35-40 Konferensbidrag (refereegranskat)abstract Effective simulation of manual assembly operations considering ergonomic load and clearance demands requires detailed modeling of human body kinematics and motions, including balance and response to external forces.In this paper we address the interaction of humans with flexible objects. By incorporating detailed physics simulation of flexible objects into the creation of ergonomically feasible human motions, we are able to ergonomically assess manual assembly operations involving cables and hoses.The method is implemented and demonstrated on a challenging operation taken from the automotive industry; a wiring harness assembly.
13.	Ebrahimi, Amir Hossein, 1976, et al. (författare) Managing product and production variety - A language workbench approach 2014 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 17, s. 338-344 Konferensbidrag (refereegranskat)abstract Product platforms are commonly used in industries with complex products and high competition like the car and truck industry to allow a customer to order a product that satisfy its unique needs. A consequence of product variety is that manufacturing and assembly processes need to deal with this variety as well. If the variety is low and changes of the product occur infrequently then the variety may be handled by designing the production system for a small set of typical products. But as the variety increases and changes become frequent the necessity for integrated product and production information model is high, to partially solve this problem Product Life Cycle Management (PLM) systems aim at providing an integrated model to all categories of users, e.g. product designers, product preparation engineers, line builders and shop-floor workers. All users need to access the information in the platform and refine and modify the information to reflect new knowledge that has been acquired. Today, most often multiple systems are used where some systems may store information in a structured way but often unstructured text documents are also used. This easily results in redundant information models and automated analysis is not feasible or not event possible because of issues regarding cohesion and traceability of information. The contribution in this paper is to discuss how a new type of tool for building domain specific languages and editors using language workbench approach can be used to support the different user categories in their tasks working with variability of a product and production system while at the same time provide cohesion and traceability of information.
14.	Edh, Nina, 1984, et al. (författare) Production-related Staff's Perception of Manufacturing Strategy at a SMME 2012 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 3:1, s. 340-345 Konferensbidrag (refereegranskat)abstract Today's global competitiveness urges SMMEs to pay attention to their MS process. The purpose of this case study at a Swedish SMME, mainly conducted through interviews with production-related staff: staff with direct connection to everyday production work, is to explore their perception of the MS content. The study shows that communication is the main obstacle for production-related staff's perception of the MS. Their perception is diverse and based on a multitude of factors, such as employment period, organizational belonging, and the employees’ own interest. Several problem areas are identified and need to be investigated further.
15.	Elfving, Sofi W, et al. (författare) At a Crossroads : Case Study Analysis of the Organizational Challenges within the Transformation Path to an IPS2 2014 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271 .- 2212-8271. ; 16, s. 326-331 Tidskriftsartikel (refereegranskat)abstract Many ICT companies are transforming, going from a product focus towards more service focused business approaches. This transformation process has been on-going for a couple of decades now and places high demands, not only on the technological development and business models but also on the companies ability to mature and transform the organizational setup, leadership capabilities, and the need for different types of competencies. This paper analyzes the servitization process within the ICT industry by presenting a case study that addresses the organizational challenges and gives tentative answers on how to cope with them.
16.	Elo, Kristofer, et al. (författare) Automatic Dismantling Challenges in the Structural Design of LCD TVs 2014 Ingår i: Procedia CIRP. - : Elsevier. - 2212-8271 .- 2212-8271. ; 15, s. 251-256 Tidskriftsartikel (refereegranskat)abstract Many liquid crystal display television sets (LCD TVs) end up in the waste stream today. The combination of hazardous materials such as mercury and liquid crystal, and the labor-intensive disassembly of LCD TVs, make the recycling process interesting to automate. However, since there are so many manufacturers the variation of LCD TVs is high, making automation a challenge. Todays most common automatic process utilizes shredders, resulting in degradation of recycled material and possible decontamination of machine equipment. This paper aims to investigate the challenges related to the structural design of LCD TVs for an automatic dismantling process for the recycling of LCD TVs. The challenges identified during the empirical study were related to the mixture of materials, inhomogeneous materials, thin design, separation of the different components and finding a suitable dismantling sequence without unnecessary removal of components.
17.	Elo, Kristofer, 1983-, et al. (författare) Process concepts for semi-automatic dismantling of LCD televisions 2014 Ingår i: Procedia CIRP. - : Elsevier. - 2212-8271 .- 2212-8271. ; 23:2014, s. 270-275 Tidskriftsartikel (refereegranskat)abstract There is a large variety of electrical and electronic equipment products, for example liquid crystal display television sets (LCD TVs), in the waste stream today. Many LCD TVs contain mercury, which is a challenge to treat at the recycling plants. Two current used processes to recycle LCD TVs are automated shredding and manual disassembly. This paper aims to present concepts for semi-automated dismantling processes for LCD TVs in order to achieve higher productivity and flexibility, and in turn increase the value of the recycled materials, improve the work environment for operators and remove mercury from the recycled materials. A literature review and two empirical studies were performed to be able to present a concept for dismantling direct illuminated LCD TVs. The process used a circular saw and/or a band saw to machine two cuts in LCD TVs to gain access to the mercury-containing cold cathode fluorescent lamps inside. This conceptual process is compared to the other processes found in the literature.
18.	Eynian, Mahdi, 1980- (författare) Frequency Domain Study of Vibrations above and under Stability Lobes in Machining Systems 2014 Ingår i: Procedia CIRP. - : Elsevier. - 2212-8271 .- 2212-8271. ; 14, s. 164-169 Tidskriftsartikel (refereegranskat)abstract Using modified Nyquist contours, the dominant poles of the closed loop delay-differential equation for machining systems such as milling are identified. Contours with constant damping ratio of the dominant poles are constructed using this method. These contours are similar in shape to the stability lobes, but move upwards and to the right as the instability parameter increases. Additionally, it is possible to study the movement of the dominant poles to the right-hand side of the complex plane as the system becomes unstable by increasing the depth of cut at a constant spindle speed. The movement of the dominant pole is shown to be towards the right (unstable) and upward (higher vibration frequency) of the complex plane. In some cases, there would be a jump of vibration frequency due to the change of the lobe number. It is also shown that the damping ratio of the structure strongly affects both the vibration frequency and the damping ratio of the dominant poles in the closed loop system. Finally, in two milling experiments with two different spindle speeds and continuously increasing depth of cuts, vibration frequencies are measured and compared to the theoretical predictions. The measurements agree with the theoretical predictions, particularly in the unstable cutting conditions.
19.	Fasth Berglund, Åsa, 1978, et al. (författare) Cognitive automation strategie: Improving use-efficiency of carrier and content of information 2014 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 17, s. 67-70 Konferensbidrag (refereegranskat)abstract The production paradigm of mass customization puts high demand on the production system and the people who works there. This is especially true for final assembly where the number of variants is the richest. To handle this variety, the operator needs the correct information accessible at the right time; the operator wants to know how and when to assemble what part. What is correct information includes the amount of information (content of information), how it is presented (carrier of information) and who is the receiver (specific operator). The strategy for Cognitive Automation will be more and more important for companies within this paradigm. This paper aims to show the use-Efficiency of information, both carrier and content, in two industrial case studies. Furthermore how the cognitive automation strategy within a company is connected to the maturity of technology. ©2014 Elsevier B.V. This is an open access article under the CC BY-NC-ND license.
20.	Fasth Berglund, Åsa, 1978, et al. (författare) Using the TRL methodology to design supporting ICT-tools for production operator 2014 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 17, s. 726-731 Konferensbidrag (refereegranskat)abstract The Technology Readiness Level or TRL, has a long history at NASA and American Department of Defence (DoD), when designing and testing new technologies. Could this methodology be used in a production system context? Due to the increased information complexity in production systems today new technologies and prototypes have to be developed and tested more frequently. Cognitive automation strategies are becoming a competitive benefit for the companies that have a standardisation when it comes to prototyping and testing. The aim of this paper is to show how the TRL could be used to design supporting ICT-tools for operators in Swedish production. The internal testing has been done at the university lab, and the external tests have been done in two industrial case studies as an input for the results in this paper. Results show that even though it is good to have a structured methodology to follow, it is difficult to put the methodology to use in a different context.
21.	Fasth, Åsa, 1978, et al. (författare) From Task Allocation Towards Resource Allocation when Optimising Assembly Systems 2012 Ingår i: Procedia CIRP - Elsevier. - 2212-8271. ; 3, s. 400-405 Tidskriftsartikel (refereegranskat)abstract The article discusses the question; is it possible to reach route flexibility and system proactivity through resource allocation and task optimisation. In order to answer this, differences between three types of optimisation regarding task and resource allocation are discussed: Global Task and Resource optimisation, Task optimisation and local resource allocation, but with resource alternatives, Task optimisation and local resource allocation (optimisation), with prioritised resources, shown as a possible solution in this paper in order to increase the route flexibility and proactivity in the system planning. An example of the last approach will be shown using a logic language (SOP) with help of software tool called Sequence Planner (SP).
22.	Friel, R. J., 1982-, et al. (författare) Ultrasonic additive manufacturing – A hybrid production process for novel functional products 2013 Ingår i: Procedia CIRP. - Amsterdam : Elsevier. - 2212-8271 .- 2212-8271. ; 6, s. 35-40 Tidskriftsartikel (refereegranskat)abstract Ultrasonic Additive Manufacturing (UAM), or Ultrasonic Consolidation as it is also referred, is a hybrid form of manufacture, primarily for metal components. The unique nature of the process permits extremely novel functionality to be realised such as multi-material structures with embedded componentry. UAM has been subject to research and investigation at Loughborough University since 2001. This paper introduces UAM then details a number of key findings in a number of areas that have been of particular focus at Loughborough in recent years. These include; the influence of pre-process material texture on interlaminar bonding, secure fibre positioning through laser machined channels, and freeform electrical circuitry integration. © 2013 The Authors.
23.	Hedman, Richard, 1984, et al. (författare) Object-oriented Modeling of Manufacturing Resources Using Work Study Inputs 2013 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 7, s. 443-448 Konferensbidrag (refereegranskat)abstract Resources are the core of manufacturing models. They provide information about the people and equipment that perform activities on the shop floor. Comprehensive representations of equipment are common but human resources are often defined to a very limited extent. This paper presents how work study data can be applied as input to detailed modeling of human manufacturing resources. The purpose is to provide a valid representation of manual work tasks on a shop floor level. If implemented in manufacturing models the valid representation will contribute to improve planning, control and execution of production. It also facilitates and encourages production improvement initiatives.
24.	Holm, Magnus, et al. (författare) Adaptive decision support for shop-floor operators in automotive industry 2014 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; , s. 440-445 Konferensbidrag (refereegranskat)abstract Today's operators on factory shop-floors are often not stationed, dealing with a single or few tasks but have increasing responsibilities demanding enhanced skills and knowledge in a production environment where any disturbance must be settled with adequate actions without delay to keep optimum output. To be able to respond to these demands, the operators need dynamic, distributed and adaptive decision support in real-Time, helping them to distinguish decision options and maximizing productivity despite incoming stochastic events. The minimum of time and option for operators to consider appropriate action both during normal production and when facing unexpected or unscheduled events point out the need of adaptive decision support for operators. When initiating this research project the question from the industry partner was the following: In what ways is it possible to support operators in making decisions for optimal productivity? By targeting this problem this paper introduces a novel framework for an adaptive decision-support system enabled by event-driven function blocks and based on decision logics. The proposed decision support systems' ability to adapt to the actual conditions on the shop-floor is validated through a case study, and its capability is compared to the voice message system installed on-site.
25.	Hosseini, Seyed, 1981, et al. (författare) Characterization of the Surface Integrity induced by Hard Turning of Bainitic and Martensitic AISI 52100 Steel 2012 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 1:1, s. 494 - 499 Konferensbidrag (refereegranskat)abstract Depending on the process parameters and the tool condition, hard turned surfaces can consist of a “white” and a “dark” etching layer having other mechanical properties compared to the bulk material. X-ray diffraction measurements revealed that tensileresidual stresses accompanied with higher volume fraction of retained austenite are present in the thermally induced white layer. While compressive residual stresses and decreased retained austenite content was found in the plastically created white layer. The surface temperature was estimated to be ~1200 C during white layer formation by hard turning.
26.	Hosseini, Seyed, 1981, et al. (författare) Dissolution of iron-chromium carbides during white layer formation induced by hard turning of AISI 52100 steel 2014 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 14, s. 107-112 Konferensbidrag (refereegranskat)abstract The (Fe, Cr)3C carbide morphology in the surface region of hard turned bainitic AISI 52100 steel was investigated using both experimental techniques and simulations, where microstructural analysis was correlated with analytical studies of the carbide dissolution kinetics using DICTRA1. The experimental results showed that for both predominantly thermally and mechanically induced white layers no significant carbide dissolution took place down to a depth of 20 μm below the machined surfaces. This was confirmed by the analytical results from DICTRA, which showed that no significant carbide dissolution should take place during hard turning given the short contact times. Within the hard turned surfaces up to ∼12% of the carbides were elongated, indicating plastic deformation of the carbides during machining.
27.	Jareteg, Cornelia, 1986, et al. (författare) Variation simulation for composite parts and assemblies including variation in fiber orientation and thickness 2014 Ingår i: Procedia CIRP CATS 2014. 5th CATS 2014 - CIRP Conference on Assembly Technologies and Systems. - : Elsevier BV. - 2212-8271. ; 23, s. 235-240 Konferensbidrag (refereegranskat)abstract All manufacturing processes are afflicted by geometrical variation, which can lead to defect products. A simulation tool for geometry assurance analysis is therefore important in the design process. The use of composites has recently increased drastically, but there is still a lack of understanding about the effects of variation in such parts. A method for predicting variation in subassemblies, including variation in fiber orientation and ply thickness for composites is presented. The approach is demonstrated on an industrial case and finite element analysis is used to calculate the deformation. In particular, contribution from variation in material properties to the variation in critical points is analyzed. The results indicate that material uncertainties have a small impact on the geometric variation for the test case.
28.	Johansson, Carl-Anders, et al. (författare) Context Driven Remaining Useful Life Estimation 2014 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271 .- 2212-8271. ; 22, s. 181-185 Tidskriftsartikel (refereegranskat)abstract In the context of maintenance activities maintainers rely on machine information, their past breakdowns, adequate repair methods and guidelines as well as new research results in the area. They usually get access to information and knowledge by using information systems (nondestructive testing (NDT) or condition monitoring.), local databases, e-resources or traditional print media. Basically it can be assumed that, the amount of available information affects the quality of maintenance decision making and acting positively. Machine health information retrieval is the application of information retrieval concepts and techniques to the operation and maintenance domain. Retrieving Contextual information, describing the operational conditions for the machine, is a subarea of information retrieval that incorporates context features in the search process towards its improvement. Both areas have been gaining interest from the research community in order to perform more accurate prognostics according to specific scenarios and happening circumstances. Context is a broad term and in this paper the operational conditions and the way the machine has been used is seen as the context and is represented by operational data collected over time. This paper intends to investigate the effects of the interaction of context features on machine tools health information. This interaction between context and health assessment is bidirectional in the sense that health information seeking behavior can also be used to predict context features that can be used, without disturbing the operational environment and creating production disruptions.The extraction of multiple features from multiple sensors, already deployed in this type of machinery, may constitute snapshots of the current health of certain machine components. The mutation status (the way they have changed) of these snapshots, hereafter called Fingerprints, has been proposed as prognostic marker in machine tools problems. Of them, in this work so far only the spindle fingerprint mutation has been validated independently as prognostic for overall survival and survival after relapse, while the prognostic value of rest of components mutation is still under validation. In this scenario, the prognostic value of spindle fingerprint mutations can be investigated in various contexts defined by stratifications of the machine population.
29.	Johansson, Pierre, 1986, et al. (författare) Current state of standardized work in automotive industry in Sweden 2013 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 7, s. 151-156 Konferensbidrag (refereegranskat)abstract Standardized work has been one of several larger research topics in the automotive industry over the years. This paper gives a brief view of the current situation of standardized work in the automotive industry in Sweden. The paper is based on recently performed studies at several automotive actors in Sweden. Most of the present research about standardized work focuses on local premises. Therefore, this paper suggests more focus in future research on how to implement standardized work in global organizations focusing on local demands and cultural differences and similarities. © 2013 The Authors.
30.	Kirkhorn, Lanny, et al. (författare) Improved Tribotesting for Sheet Metal Forming 2012 Ingår i: 45th CIRP Conference on Manufacturing Systems 2012. - : Elsevier BV. - 2212-8271. - 9781627485128 ; 3, s. 507-512 Konferensbidrag (refereegranskat)abstract A new tribotester has been developed to characterize the friction conditions in sheet metal forming applications. The basic principle for the tribotester is parallel strip drawing. This apparatus is an improvement on conventional test setups in that it offers controllable speed and normal load during experimenting, a tool size that is variable over a wide range, and direct force measurement to allow the calculation of friction coefficients without using internal material deformation. These features increase the efficiency of the testing procedure when developing new tooling concepts within the sheet metal forming industry.
31.	Kyösti, Petter, et al. (författare) A Decision Support Tool for Optimising Support Site Configuration of Functional Products : Special Session: Product Development for Through-Life Engineering Services 2014 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271 .- 2212-8271. ; 22, s. 175-180 Tidskriftsartikel (refereegranskat)abstract The customization of the support site configuration (including the number, locations and capabilities of sites where maintenance staff are based) is of critical importance to functional product providers, who must provide maintenance support services for products operated by their customers at different locations and ensure that contractual guarantees for functional availability are met whilst keeping support costs under control. Since contract fulfilment costs are performance based and long term, they are difficult to predict without modelling. This paper discusses a decision support tool designed for use by management and engineering personnel at Functional Product providers to analyse and optimize the performance of their support base configuration. It features a graphical user interface for configuration customization, simulation modelling to predict performance and outputs a wide range of analytics that can be used to compare and optimize configurations. The tool is demonstrated via application to an industrial test case
32.	Lindahl, Mattias, 1971-, et al. (författare) Actor's and System Maps for Integrated Product Service Offerings : Practical Experience from Two Companies 2014 Ingår i: Procedia CIRP. - Elsevier : Elsevier BV. - 2212-8271. ; 16, s. 320-325 Tidskriftsartikel (refereegranskat)abstract The objective is to analyze how proposed Integrated Product Service Offering (IPSO) actors and system maps can be utilized in order to identify and access IPSO-related requirements. Furthermore, the objective is to identify and analyze how IPSO-related requirements are managed and transformed into product-related design aspects. Literature review, interviews and workshops were the primary research methods used. The conclusion is that participating companies have realized that there are several issues within their operations that can be improved, and proposed maps provide support for this. These maps provide useful detailed information compared to other approaches, and are easy to use.
33.	Lindskog, Erik, 1988, et al. (författare) Visualization Support for Virtual Redesign of Manufacturing Systems 2013 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 7, s. 419-424 Konferensbidrag (refereegranskat)abstract Rapidly changing products and market demand call for manufacturing systems to be continuously adapted and developed. The process of modifying manufacturing systems requires large amounts of planning involving contributions from personnel across an organization. These people need a shared understanding of the future system, including but not limited to its design, functions, and expected performance. One common representation in the virtual manufacturing system domain are 2D CAD layouts. Typical problems with such traditional 2D models are that only experts understand the content fully. For increased understanding, 3D CAD models could bridge the gap between different areas of expertise. However, creating 3D models representing the complete system is traditionally time-consuming, resulting in oversimplified models or limited to parts of the system. Furthermore, such models normally contain uncertainty about building-related geometries that could incur costly mistakes if used as basis for decisions, e.g. realizing during installation of a machine that roof-beams interfere with the planned placement. This paper evaluates what type of problems can be solved with better visualization support, e.g. issues concerning workshop-layout, production flow, workplace design, etc. The evaluation is based on two case studies at different manufacturing sites during ongoing system redesign processes. The case studies implemented visualization using a combination of CAD models and 3D laser scanned as-built data of the current system and facility. The vision is to implement the Lean concept of “Go to Gemba” for a future state in a virtual environment. Bringing this concept into the early phases of manufacturing system redesign has the potential to facilitate the creation of a shared understanding of the future system within cross-functional project teams.
34.	Lindström, John, et al. (författare) Functional Products lifecycle: Governed by sustainable win-win situations 2014 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 22:1, s. 163-168 Konferensbidrag (refereegranskat)abstract The paper proposes a Functional Products (FP) lifecycle viewed from economic, ecologic and societal perspectives. The overall FP lifecycle is further discussed from the viewpoint of its technical and economic lifecycles. The paper suggests that the overall FP lifecycle is governed by a sustainable win-win situation between the provider and customer sides, and thus that there needs to be a balance regarding the perceived value for both parties.
35.	Lindström, John, et al. (författare) Use of cloud services in functional products : availability implications 2014 Ingår i: Product Services Systems and Value Creation. - : Elsevier. ; 16, s. 368-372 Konferensbidrag (refereegranskat)abstract The paper addresses the potential use of cloud services in Functional Products (FP) and its possible implications for availability. Further, how the implications for availability can be understood via modelling and simulation is addressed. The paper adds further specificity to literature by indicating the FP constituents for which cloud services are applicable and adequate.
36.	Lu, B., et al. (författare) Reusability based on life cycle sustainability assessment : Case study on WEEE 2014 Ingår i: Procedia CIRP. - : Elsevier. - 2212-8271. Konferensbidrag (refereegranskat)abstract 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.
37.	Malakizadi, Amir, 1983, et al. (författare) Wear mechanism of CBN inserts during machining of bimetal aluminum-grey cast iron engine block 2013 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 8, s. 188-193 Konferensbidrag (refereegranskat)abstract In this study, the wear mechanism of CBN inserts while face milling of aluminum-grey cast iron engine block was investigated by means of Scanning Electron Microscopy (SEM). It was shown that the thermal cracking constitutes the main wear mechanism. The Finite Element Method (FEM) was utilized to simulate the face milling under the operational condition. The flow stress properties of the aluminum-silicon alloy and grey cast iron were determined by means of inverse methodology and the milling operation was modeled separately for each material to obtain the thermally and mechanically induced stresses on the tool edge. The methodology presented in this paper can be used to find the optimum cutting condition as well as tool geometry to reduce tool wear rate.
38.	Mattsson, Sandra, 1984, et al. (författare) Managing production complexity by empowering workers: six cases 2014 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 17, s. 212-217 Konferensbidrag (refereegranskat)abstract To manage high product variety many companies empower their operators. Reaching the benefits of that is connected tosuccessfully distributing role allotments and work tasks in the complex context. The characteristic of empowerment is studied in six cases where the focus is work tasks and power to affect the company. Results indicate that the workers are, in general,responsible for more than 30% of the tasks connected to the production but that they do not always have the power to make decisions that influence the organization directly. This could increase the companies’ attractiveness as a future employer and itscompetitiveness.
39.	Mattsson, Sandra, 1984, et al. (författare) Testing Complexity Index – a Method for Measuring Perceived Production Complexity 2012 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 3:1, s. 394-399, s. 394-399 Konferensbidrag (refereegranskat)abstract Complexcity Index (CXI) is a method developed to help manufacturing companies to describe complexity as experienced and to assist in reducing the effects it has on operator performance. The method is targeting the perceived complexity and was tested at Volvo Cars Corporation. Reproducibility of the method could be seen between respondents and was considered a valuable tool for visualizing problem-areas at the stations. It is suggested that objective data could be one way to identify which stations should be tested in-depth with the CXI method, and that CXI could be used for suggesting improvements or appropriate support tools.
40.	Mohammed, Abdullah, et al. (författare) Integrated Image Processing and Path Planning for Robotic Sketching 2013 Ingår i: Procedia CIRP. - : Elsevier. - 2212-8271 .- 2212-8271. ; 12, s. 199-204 Tidskriftsartikel (refereegranskat)abstract Since the beginning of the development of machine vision, researchers have realized its importance in the robotics field, as it provides a useful tool for both the environment detection and decision making during the automation process. At the same time, path planning for robots influences many in the robotics and automation field and it has remained active for both methodology research and system implementation. This research combines machine vision with robot path planning with an aim of programming-free robotic applications. Particularly as a proof of concept, a programming-free robotic sketching prototype is developed as a case study. Within the context, this paper consists of three parts. The first part covers the processing of a facial image taken by a webcam to identify the contours that represent the image; the second part converts these contours to paths for an industrial robot to follow; and the third part controls the robot adaptively for sketching including auto-generation of control codes and self-calibration. The developed prototype is a closed-loop system with networked camera and robot. Intelligent computation is applied to identify the contours of the image with minimum representation of points and with the correct sequence of points for each curve (path); the sequence of the output robot paths represents the near-optimal sequence to preserve the minimum travelling time for the robot. The robot control module can also retrieve the TCP of the robot for off-site monitoring. The ultimate goal of this research is future applications of robot path following, e.g. ad-hoc robotic cutting or welding where the paths can be specified by hand-drawings of an operator on the target workpiece with zero programming for the operator.
41.	Mårdberg, Peter, 1980, et al. (författare) Using a Formal High-level Language to Instruct Manikins to Assemble Cables 2014 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 23:C, s. 29-34 Konferensbidrag (refereegranskat)abstract In this paper, a formal high-level language is used to generate simulations where a manikin assembles flexible cables. The language generates assembly instructions for the manikin, which automatically performs the corresponding assembly motion with as good ergonomic as possible. Due to weight, stiffness and narrow regions, it may be difficult to perform an assembly of the cable. Our approach allows us to verify that it may be performed in an ergonomically sound way. The generated instructions are formally verified to ensure that assembly order is held and to prevent erroneous assembly states. The simulations have been made on industrial test cases.
42.	Nayyar, Varun, 1981, et al. (författare) An Experimental Investigation of Machinability of Graphitic Cast Iron Grades; Flake, Compacted and Spheroidal Graphite Iron in Continuous Machining Operations 2012 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 1:1, s. 488-493 Konferensbidrag (refereegranskat)abstract In this study the machinability of different grades of cast iron has been studied in terms of cutting temperatures, cutting forces, tool life, deformed chip thickness and contact length in different continuous machining operations. The tests performed were: external turning, boring and face turning. Pearlitic Flake Graphite Iron (FGI), Compacted Graphite Iron (CGI) and Spheroidal Graphite Iron (SGI) materials were selected for making the experiments. Later the machinability was also compared with ferritic SGI material. The cutting temperature has been measured with the help of thermocouple insisted inserts. These inserts were having 2 junctions; 0.55 and 1.2 mm away from the cutting edge on the clearance face. It has been seen that the cutting temperature on the clearance face has not shown any significant difference for different grades of cast irons. However, the tool life and the cutting forces have shown significant differences. The face turning tests were performed in both dry and wet conditions to see the importance of cutting fluids for different grades of cast iron. It has been seen that the CGI and SGI requires cutting fluid in a continuous machining operation. It has been seen that CGI and SGI require cutting fluid in a continuous machining operation. Later the wear mechanisms of different grades were also studied for dry and wet conditions in a boring operation. Both CGI and SGI have shown adhesion as a wear mechanism under dry conditions as compared to abrasive wear in wet conditions with a cutting speed of 300 m/min. The results can be input to designing a suitable insert for CGI and SGI and highlights the importance of using cutting fluids while machining CGI and SGI in a continuous turning operation.
43.	Parida, Vinit, et al. (författare) A Survey Study of the Transitioning towards High-Value Industrial Product-Services 2014 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271 .- 2212-8271. ; 16, s. 176-180 Tidskriftsartikel (refereegranskat)abstract Servitization literature suggests that traditional manufacturing companies are increasingly offering industrial services in order to increase their position in the global competition. However, little is known about extent and profit potential of different types of such offers in current industry. This paper offers an overview of such offers and concludes that maintenance based business models are most closely linked to increased revenue generation while add-on services have a negative effect. Future trends, suggest that business models such as R&D services and functional services will be increasingly important in the future.
44.	Parida, Vinit, et al. (författare) Win-Win collaboration, functional product challenges and value-chain delivery : An explorative case study approach 2013 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271 .- 2212-8271. ; 11, s. 86-91 Tidskriftsartikel (refereegranskat)abstract Functional products (FPs) comprises of integrated hardware, software, and a service support system components that are bundled together to offer higher customer value and possibility to generate revenue. However, offering FPs requires forming and managing win-win collaboration with diverse global value chain partners. Based on twenty explorative interviews at two Swedish manufacturing companies, we specifically focus on the collaboration between FP provider and its value-chain delivery organizations. Our results show that such collaborations can lead to win-lose or lose-win situations. Furthermore, we identify six diverse relational challenges which could negatively influence the collaboration between FP providers and its value-chain delivery organizations
45.	Parsian, Amir, 1982-, et al. (författare) A Mechanistic Approach to Model Cutting Forces in Drilling with Indexable Inserts 2014 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271 .- 2212-8271. ; 24:0, s. 74-79 Tidskriftsartikel (refereegranskat)abstract Holes are made in many industrial parts that need screws, pins or channels for passing fluids. The general method to produce holes in metal cutting is by drilling operations. Indexable insert drills are often used to make short holes at a low cost. However, indexable drills are prone to vibrate under certain circumstances, causing vibrations that affect tool life. Therefore, a good prediction of cutting-forces in drilling is important to get a good description of the cutting process for optimization of tool body and insert design. Reliable simulations of dynamic forces also aid in prediction of chatter vibrations that have significant effects on the quality of the manufactured parts as well as the tool life. In this paper, a mechanistic approach is used to model the cutting-forces. Cutting-force coefficients are identified from measured instantaneous forces in drilling operations. These coefficients are used for simulating torque around drill-axis, axial force and cutting-forces in the plane perpendicular to drill-axis. The forces are modeled separately for peripheral and central insert, which results in a detailed description of the cutting-forces acting on each insert. The forces acting on each insert are estimated by dividing the cutting edges into small segments and the cutting-forces acting on each segment are calculated. The total forces are predicted by summation of the forces acting on each segment. Simulated torque and forces are compared to measured cutting-forces for two different feeds. A good agreement between predicted and experimental results, especially in torque and axial-force, is observed.
46.	Pavasson, Jonas, et al. (författare) Challenges and opportunities within simulation-driven functional product development and operation : Special Session: Product Development for Through-Life Engineering Services 2014 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271 .- 2212-8271. ; 22, s. 169-174 Tidskriftsartikel (refereegranskat)abstract The product development process at industrial companies has traditionally focused on hardware-oriented solutions. Business strategies strive towards more service-oriented solutions e.g., functional product business models. In this paper two case studies are developed and the objective is to highlight important challenges and opportunities by implementing a simulation-driven strategy in functional product development and operation. It can be concluded that challenges and opportunities within simulation-driven functional product development and operation are related to both quality and management of the simulations. With the proposed strategies for validation and coupling of the simulations, some of the challenges within functional product development can be overcome.
47.	Pavasson, Jonas, et al. (författare) Simulation-driven mobility function development 2013 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271 .- 2212-8271. ; 11, s. 157-162 Tidskriftsartikel (refereegranskat)abstract A trend among industrial companies is to change business strategies from hardware-oriented to more service-oriented solutions, e.g. functional product business models. In this paper, a mobility function scenario is developed and the objective is to derive a simulation-driven methodology for development of sustainable mobility functions. It can be concluded that mobility function solutions may create incitements for sustainability. When developing mobility functions, a lot of new requirements, brought about by increased product complexity, need to be managed by the simulation methodology. However, the proposed simulation strategy can be used to drive mobility function development.
48.	Pejryd, Lars, 1955-, et al. (författare) Computed Tomography as a Tool for Examining Surface Integrity in Drilled Holes in CFRP Composites 2014 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271 .- 2212-8271. ; 13, s. 43-48 Tidskriftsartikel (refereegranskat)abstract In light weight structures the joining of composite materials and of composites to metals are key technologies. A manufacturing method associated with joining is the drilling of holes. The hole creation in CRFP through drilling is associated with several defects related to the process, both on the entry and exit sides of the hole and also with dimensional and surface roughness issues of the hole wall. The detection of damage due to the process is not trivial. Especially interesting is non-destructive methods. In this work X-ray computed tomography is used to determine defects due to drilling of holes in a CFRP composite using twist drills with different geometrical features at different drilling parameters. The results can be used to establish relationship between different geometrical features of drills in combination with cutting parameters and resulting surface integrity of holes. © 2014 The Authors. Published by Elsevier B.V.
49.	Pejryd, Lars, 1955-, et al. (författare) Machine Tool Internal Encoders as Sensors for the Detection of Tool Wear 2012 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271 .- 2212-8271. ; 4, s. 46-51 Tidskriftsartikel (refereegranskat)abstract Tool wear in machining changes the geometry of the cutting edges, which effect the direction and amplitudes of the cutting forcecomponents and the dynamics in the machining process. These changes in the forces and dynamics are picked up by the internalencoders and thus can be used for monitoring of changes in process conditions. This paper presents an approach for the monitoringof a multi-tooth milling process. The method is based on the direct measurement of the output from the position encoders availablein the machine tool and the application of advanced signal analysis methods.The paper investigates repeatability of the method developed and how to detect wear in an individual tooth in a milling cutter. Theresults of this work show that various signal features which correlate with tool wear can be extracted from the first few oscillatingcomponents, representing the low-frequency components, of the machine axes velocities. The responses from the position encodersexhibit good repeatability, especially short term repeatability while the long-term repeatability is more unreliable. A worn toothincreases the irregularity in the encoder responses and can be identified at an early stage of the cut.
50.	Pervaiz, Salman, et al. (författare) A coupled FE and CFD approach to predict the cutting tool temperature profile in machining 2014 Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271 .- 2212-8271. ; 17, s. 750-754 Tidskriftsartikel (refereegranskat)abstract The paper presents an innovative methodology of coupling the conventional finite element machining simulations with computational fluid dynamic (CFD) model to analyse the temperature distribution at the cutting tool. The conventional finite element machining simulations were conducted using DEFORM 2D to predict the heat generation and tool tip temperature during the cutting action. Machining simulations were conducted using Ti6Al4V and uncoated carbide as a workpiece and tool material respectively. Modified version of Johnson-Cook constitutive model was incorporated in the conventional finite element based machining simulations to predict the behavior of flow stresses for Ti6Al4V titanium alloy. Computational fluid dynamics (CFD) simulations were performed using ANSYS (R) CFX. CFD model has incorporated air as a cooling media to simulate the dry cutting and temperature distribution at the tool surface was obtained. The coupled numerical modeling methodology showed encouraging potential of predicting precise temperature distribution on the cutting tool. The approach can be further evaluated to predict temperature distribution under flood cooling and minimum quantity lubrication (MQL).

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