| 1. |
- Augustsson, Svante, 1983-, et al.
(author)
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How to Transfer Information Between Collaborating Human Operators and Industrial Robots in an Assembly
- 2014
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In: Proceedings the NordiCHI 2014: The 8th Nordic Conference on Human-Computer Interaction. - New York, NY, USA : ACM Publications. - 9781450325424 ; , s. 286-294
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Conference paper (peer-reviewed)abstract
- Flexible human-robot industrial coproduction will be important in many small and middle-sized companies in the future. One of the major challenges in a flexible robot cell is how to transfer information between the human and the robot with help of existing and safety approved equipment. In this paper a case study will be presented where the first half focus on data transfer to the robot communicating the human's position and movements forcing the robot to respond to the triggers. The second half focuses on how to visualize information about the settings and assembly order to the human. The outcome was successful and flexible, efficient coproduction could be achieved but also a number of new challenges were found.
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| 2. |
- Augustsson, Svante, 1983-, et al.
(author)
-
Human and robot interaction based on safety zones in a shared work environment
- 2014
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In: HRI '14. - New York : ACM Publications. - 9781450326582 ; , s. 118-119
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Conference paper (peer-reviewed)abstract
- In this paper, early work on how to implement flexible safety zones is presented. In the case study an industrial robot cell emulates the environment at a wall construction site, with a robot performing nailing routines. Tests are performed with humans entering the safety zones of a SafetyEye system. The zone violation is detected, and new warning zones initiated. The robot retracts but continues its work tasks with reduced speed and within a safe distance of the human operator. Interaction is achieved through simultaneous work on the same work piece and the warning zones can be initiated and adjusted in a flexible way.
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| 3. |
- Bolmsjö, Gunnar, 1955-, et al.
(author)
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Collaborative Robots to Support Flexible Operation in a Manufacturing System
- 2012
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In: Flexible Automation and Intelligent Manufacturing, FAIM 2012. - Tampere, Finland : Tampere University. - 9789521527838 - 9789521527845 ; , s. 531-538
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Conference paper (peer-reviewed)abstract
- Collaborative robotic systems where human(s) and robot(s) cooperate in performing a common task is an attractive solution to introduce automation combined with high flexibility for tasks that have a high complexity and characterized by low volume or down to one-off. By introducing collaboration in robotics systems, the operator can complement with cognitive capacity and skill in order to gain in flexibility and agility in the task operation. This paper describes on-going work related to work on collaboration between operator and robot. User scenarios are outlined together with methods, software components and hardware to support collaboration, where some of these are under development. As the standards related to collaborative robotic systems are soon to be completed, it is expected that this type of semi-automatic systems will be important for flexible and agile automation of production which otherwise cannot be automated.
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| 4. |
- Bolmsjö, Gunnar, 1955-
(author)
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Reconfigurable and Flexible Industrial Robot Systems
- 2014
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In: Advances in robotics & automation. - : OMICS international. - 2168-9695. ; 3
-
Research review (other academic/artistic)abstract
- This paper presents a concept for reconfigurable and flexible robot systems. To reach a technology readiness level where solutions and results can be implemented in industry, the focus in this work is on systems with limited number of robots, and work scenarios which are reasonable complex but hard to automate using standard solutions.Four distinct areas have been identified as important within the concept and further studies: (i) human machine interaction, (ii) safety including collaboration, (iii) programming and deployment, and (iv) planning and scheduling. Feasibility studies have been made which addressed issues (ii) and (iii), in scenarios with collaboration between robot and human, or between two robots. For the chosen work scenario, manufacturing of structures in wood for family houses, challenges related to programming and safety was identified and possible solutions outlined.The concept and the studies indicate that feasible solutions can be found and designed given a reasonable consistent work processes and products. In this study, the processes are similar, nailing and screwing but different sizes may apply, the material is similar but variations may apply, and the construction is different of each product, but include the same type of operations at different locations. Our study confirm that human collaboration improves the ability to implement and use robots as it make it possible to move some operations to the human which otherwise would add to the complexity of the system. Furthermore, programming can also I general be simplified although methods for automatic programming has been tried out. But in some cases, the solution space is limited and the ability to move certain operations to a human simplifies the programming task. However, further work needs to be done in this area specifically related to safety issues for safe collaboration.
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| 5. |
- Bolmsjö, Gunnar, 1955-, et al.
(author)
-
Robotic Friction Stir Welding of complex geometry and mixed materials
- 2018
-
In: 50th International Symposium on Robotics, ISR 2018. - : VDE Verlag GmbH. - 9783800746996 - 9781510870314 ; , s. 35-41
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Conference paper (peer-reviewed)abstract
- Friction stir welding (FSW) is a solid state process for joining materials which has demonstrated advantages compares with other methods which include joining of mixed materials, hard to weld alloys and consistent and high quality. This paper presents a study of robotic FSW initiated by Volvo Skövde plant to join an insert workpiece of extruded aluminium with a cylinder block of aluminium casting. A three-stage procedure was decided to determine the feasibility to apply robotic FSW. The stages included study of welding the mixed materials, weld along the complex joint line with holes and channels close to the joint, and finally welding the cylinder block. The results based on preliminary analysis indicate that the final tests were successful and the process is feasible for the challenging case study. However, further studies are recommended in order to identify the operating parameters window, tool design, and control of the process in order to optimize productivity and quality. © VDE VERLAG GMBH
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| 6. |
- Bolmsjö, Gunnar, 1955-
(author)
-
Smart Industri och Akademien
- 2019
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In: Presenterades på Regiondagarna 2019.
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Conference paper (pop. science, debate, etc.)
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| 7. |
- Bolmsjö, Gunnar, 1955-
(author)
-
Supporting Tools for Operator in Robot Collaborative Mode
- 2015
-
In: 6th International Conference on Applied Human Factors and Ergonomics (AHFE 2015) and the Affiliated Conferences, AHFE 2015. - : Elsevier. ; 3, s. 409-416
-
Conference paper (peer-reviewed)abstract
- Making use of robot automation for customized products put high demand not only on the robot but on the efficiency, simplicity and flexibility to actually deploy and use robots in manufacturing stations and production lines in short batches and low volume production. Hence, market oriented product development and production requires more products to be developed and offered in less time than before, and produced for the market with more customizable options. The role of the operator is in this context an important factor and tools are needed to support the operator for highly efficient and flexible production. In this paper, the development and study of supporting tools for operators is presented. A demonstrator has been built for robotic nailing, screwing and manipulation operation in producing scaled down gable wall elements in wood for a family house. Issues raised to support the operator included automatic programming and generating relevant information for the operator for the deployment procedure to prepare for production. During production, different concepts of safety system to support collaboration mode between the operator and the robot was developed and studied. Wearable devices was used for the operator to access the information generated and different safety configurations were developed and evaluated. The baseline for this work has been to identify industrial use cases which has a clear need for automation as well as collaboration between operator(s) and robot(s). Work scenarios were discussed and analyzed with industrial partners and it was concluded that, in addition to the deployment tools, a smart safety system which is able to detect and react on humans entering the robot system work area is needed. This should support for efficient production and less downtime for both automatic mode and collaboration mode. The benefit of operator – robot collaboration is clearly shown as well as the need for supporting tools.
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| 8. |
- De Backer, Jeroen, 1987-, et al.
(author)
-
Deflection model for robotic friction stir welding
- 2014
-
In: Industrial robot. - Bingley : Emerald Group Publishing Limited. - 0143-991X .- 1758-5791. ; 41:4, s. 365-372
-
Journal article (peer-reviewed)abstract
- This paper aims to present a deflection model to improve positional accuracy of industrial robots. Earlier studies have demonstrated the lack of accuracy of heavy-duty robots when exposed to high external forces. One application where the robot is pushed to its limits in terms of forces is friction stir welding (FSW). This process requires the robot to deliver forces of several kilonewtons causing deflections in the robot joints. Especially for robots with serial kinematics, these deflections will result in significant tool deviations, leading to inferior weld quality.This paper presents a kinematic deflection model, assuming a rigid link and flexible joint serial kinematics robot. As robotic FSW is a process which involves high external loads and a constant welding speed of usually below 50 mm/s, many of the dynamic effects are negligible. The model uses force feedback from a force sensor, embedded on the robot, and predicts the tool deviation, based on the measured external forces. The deviation is fed back to the robot controller and used for online path compensation.The model is verified by subjecting an FSW tool to an external load and moving it along a path, with and without deviation compensation. The measured tool deviation with compensation was within the allowable tolerance for FSW.The model can be applied to other robots with a force sensor.The presented deflection model is based on force feedback and can predict and compensate tool deviations online.
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| 9. |
- De Backer, Jeroen, 1987-, et al.
(author)
-
Investigation of path compensation methods for robotic friction stir welding
- 2012
-
In: Industrial robot. - : Emerald Group Publishing Limited. - 0143-991X .- 1758-5791. ; 39:6, s. 601-608
-
Journal article (peer-reviewed)abstract
- Purpose – Friction stir welding (FSW) is a novel method for joining materials without using consumables and without melting the materials. The purpose of this paper is to present the state of the art in robotic FSW and outline important steps for its implementation in industry and specifically the automotive industry.Design/methodology/approach – This study focuses on the robot deflections during FSW, by relating process forces to the deviations from the programmed robot path and to the strength of the obtained joint. A robot adapted for the FSW process has been used in the experimental study. Two sensor-based methods are implemented to determine path deviations during test runs and the resulting welds were examined with respect to tensile strength and path deviation.Findings – It can be concluded that deflections must be compensated for in high strengths alloys. Several strategies can be applied including online sensing or compensation of the deflection in the robot program. The welding process was proven to be insensitive for small deviations and the presented path compensation methods are sufficient to obtain a strong and defect-free welding joint.Originality/value – This paper demonstrates the effect of FSW process forces on the robot, which is not found in literature. This is expected to contribute to the use of robots for FSW. The experiments were performed in a demonstrator facility which clearly showed the possibility of applying robotic FSW as a flexible industrial manufacturing process.
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| 10. |
- De Backer, Jeroen, 1987-, et al.
(author)
-
Temperature control of robotic friction stir welding using the thermoelectric effect
- 2014
-
In: The International Journal of Advanced Manufacturing Technology. - : Springer. - 0268-3768 .- 1433-3015. ; 70:1-4, s. 375-383
-
Journal article (peer-reviewed)abstract
- Friction stir welding (FSW) of non-linear joints receives an increasing interest from several industrial sectors like automotive, urban transport and aerospace. A force-controlled robot is particularly suitable for welding complex geometries in lightweight alloys. However, complex geometries including three-dimensional joints, non-constant thicknesses and heat sinks such as clamps cause varying heat dissipation in the welded product. This will lead to changes in the process temperature and hence an unstable FSW process with varying mechanical properties. Furthermore, overheating can lead to a meltdown, causing the tool to sink down into the workpiece. This paper describes a temperature controller that modifies the spindle speed to maintain a constant welding temperature. A newly developed temperature measurement method is used which is able to measure the average tool temperature without the need for thermocouples inside the tool. The method is used to control both the plunging and welding operation. The developments presented here are applied to a robotic FSW system and can be directly implemented in a production setting.
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| 11. |
- De Backer, Jeroen, 1987-, et al.
(author)
-
Thermoelectric method for temperature measurement in friction stir welding
- 2013
-
In: Science and technology of welding and joining. - 1362-1718 .- 1743-2936. ; 18:7, s. 541-550
-
Journal article (peer-reviewed)abstract
- Previous research within friction stir welding (FSW) has demonstrated that online control of welding parameters can improve the mechanical properties and is necessary for certain applications to guarantee a consistent weld quality. One approach to control the process is by adapting the heat input to maintain a stable welding temperature, within the specified operating boundaries. This requires accurate in-process temperature measurements. This paper presents a novel method to measure the temperature at the interface of the FSW tool and workpiece. The method is based on the thermoelectric effect between dissimilar materials. The measurements are compared to thermocouple measurements and to a physical model and show good correspondence to each other. Experiments demonstrate that the method can quickly detect temperature variations, due to geometrical variations of the workpiece or due to parameter changes. This allows use of the method for online control of robotic FSW.
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| 12. |
- Ericsson, Mikael, 1975-, et al.
(author)
-
Three-dimensional simulation of robot path and heat transfer of a TIG-welded part with complex geometry
- 2002
-
In: 11th International Conferences on Computer Technology in Welding. - : Society of Manufacturing Engineers, North American Manufacturing Research Institution. ; , s. 309-316
-
Conference paper (other academic/artistic)abstract
- The application of commercial software (OLP) packages for robot simulation, and programming, use interactive computer graphics, provide powerful tools for creating welding paths off-line. By the use of such software, problems of robot reach, accessibility, collision and timing can be eliminated during the planning stage. This paper describes how such software can be integrated with a numerical model that predicts temperature-time histories in the solid material. The objective of this integration is to develop a tool for the engineer where robot trajectories and process parameters can be optimized on parts with complex geometry. Such a tool would decrease the number of weld trials, increase productivity and reduce costs. Assumptions and principles behind the modeling techniques are presented together with experimental evaluation of the correlation between modeled and measured temperatures.
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| 13. |
- Ferreira Magalhães, Ana Catarina, 1986-, et al.
(author)
-
Thermal dissipation effect on temperature-controlled friction stir welding : [Efeito da dissipação térmica inducida durante soldadura por friçcão linear sob controlo de temperatura]
- 2019
-
In: Soldagem & Inspeção. - 0104-9224 .- 1980-6973. ; 24
-
Journal article (peer-reviewed)abstract
- During Friction Stir Welding (FSW) of complex geometries, the thermal dissipation, induced by geometric features or the surrounding environment, may strongly affect the final weld quality. In order to guarantee a consistent weld quality for different conditions, in-process welding parameter adaptation is needed. This paper studies the effect of thermal dissipation, induced by the backing bar thermal conductivity, on the weld temperature and the temperature controller response to it. A new temperature sensor solution, the Tool-Workpiece Thermocouple (TWT) method, was applied to acquire online temperature measurements during welding. An FSW-robot equipped with temperature control, achieved by rotation speed adaptation, was used. AA7075-T6 lap joints were performed with and without temperature control. The cooling rate during welding was register plus macrographs and tensile tests were assessed. The controller demonstrated a fast response promoting the heat input necessary to maintain the set welding temperature. The results demonstrated that temperature control using the TWT method is suitable to achieve higher joint performance and provides a fast setup of optimal parameters for different environments. © 2019, Universidade Federal de Uberlandia. All rights reserved.
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| 14. |
- Ferreira Magalhães, Ana Catarina, 1986-
(author)
-
Thermoelectric Measurements for Temperature Control of Robotic Friction Stir Welding
- 2020
-
Doctoral thesis (other academic/artistic)abstract
- Friction stir welding (FSW) has undergone a rapid expansion in several industrial sectors such as in the aerospace, marine, railway and automotive sectors. Current industrial applications are mainly simple long straight welds, but there is a growth of interest in components with higher geometric complexity. However, welding of geometrically complex components represents a challenging task due to the resulting uneven induced thermal dissipation along the weld, but especially due to the need for suitable equipment, able to accurately follow a complex 3D path under high mechanical loads, while managing the machine deflection. This is the case for robots, where the high process forces result in deflections, which affects robots' compliance, leading to weld failures and poor consistency in mechanical properties.In the presented approach, the rotational speed is controlled during welding in order to maintain the set temperature value along the weld. An innovative method to measure the process temperature, the tool-workpiece thermocouple (TWT), which offers a temperature estimation from the whole tool-workpiece interface (TWT-data), is set as the controlled variable. The overall aim of this thesis is then to demonstrate the industrial applicability of TWT temperature control for joining geometrically complex components using robotic friction stir welding.The TWT-data signal is demonstrated to be fast, repeatable and representative of the welding temperature. Moreover, TWT-data supplies online information during the whole weld procedure, especially during plunging. The shoulder contact with the workpiece is identified by TWT-data, providing for an improved plunging operation, which was demonstrated to significantly improve the use of robotic FSW, overcoming the lack of stiffness inherent to this equipment type at this welding stage.Improved joint performance, low tensile strength variation along the weld path and a reduced number of failed welds were achieved by welding under temperature control. As a result, such a welding approach simplifies the development of a welding procedure, allowing for a decrease in time and material. The concept was successfully validated by performing two welds consisting of two dissimilar materials in a two-dimensional weld path on a geometrically complex component by using robotic equipment. The temperature control approach is not limited to robotic equipment, but also suitable for standard FSW equipment, being of interest to a various range of applications where quality and/or time is an important factor.
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| 15. |
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| 16. |
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| 17. |
- Keyvani, Ali, 1978-, et al.
(author)
-
Using methods-time measurement to connect digital humans and motion databases
- 2013
-
In: Lecture Notes in Computer Science. - Berlin, Heidelberg : Springer Berlin Heidelberg. - 0302-9743 .- 1611-3349. - 9783642391811 ; 8026:Part 2, s. 343-352
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Journal article (peer-reviewed)abstract
- To simulate human motions in DHM tools, using techniques which are based on real human data is one promising solution. We have presented a solution in this study to connect motion databases with DHM tools. We have showed that using a motion database with MTM-based annotations is a promising way in order to synthesize natural looking motions. A platform consists of a Motion Database, a Motion Generator, and a DHM tool was introduced and tested. The results showed successful application of the presented platform in the designed test case. © 2013 Springer-Verlag.
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| 18. |
- Magalhaes, Ana, et al.
(author)
-
Thermal Dissipation Effect on Temperature-controlled Friction Stir Welding
- 2019
-
In: Soldagem & Inspeção. - : ASSOC BRASIL SOLDAGEM. - 0104-9224 .- 1980-6973. ; 24, s. 1-9
-
Journal article (peer-reviewed)abstract
- During Friction Stir Welding (FSW) of complex geometries, the thermal dissipation, induced by geometric features or the surrounding environment, may strongly affect the final weld quality. In order to guarantee a consistent weld quality for different conditions, in-process welding parameter adaptation is needed. This paper studies the effect of thermal dissipation, induced by the backing bar thermal conductivity, on the weld temperature and the temperature controller response to it. A new temperature sensor solution, the Tool-Workpiece Thermocouple (TWT) method, was applied to acquire online temperature measurements during welding. An FSW-robot equipped with temperature control, achieved by rotation speed adaptation, was used. AA7075-T6 lap joints were performed with and without temperature control. The cooling rate during welding was register plus macrographs and tensile tests were assessed. The controller demonstrated a fast response promoting the heat input necessary to maintain the set welding temperature. The results demonstrated that temperature control using the TWT method is suitable to achieve higher joint performance and provides a fast setup of optimal parameters for different environments.
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| 19. |
- Silva, Ana, 1986-, et al.
(author)
-
Analysis of Plunge and Dwell Parameters of Robotic FSW Using TWT Temperature Feedback Control
- 2016
-
In: Proceedings of 11th International Symposium on Friction Stir Welding. - Cambridge : TWI Ltd. ; , s. 1-11
-
Conference paper (other academic/artistic)abstract
- Friction stir welding (FSW) and variants of the process have generated high interest in many industries due to its several advantages such as low distortion, superior mechanical properties over arc welding and the possibility of joining dissimilar materials. Increased complexity of industrial applications require a better control of the welding process in order to guarantee a consistent weld quality. This can be achieved by implementing feedback control based on sensor measurements. Previous studies have demonstrated a direct effect of weld temperature on the mechanical properties of FSW joints, [1], and therefore, temperature is chosen as primary process variable in this study.A new method for temperature measurement in FSW referred to as the Tool-WorkpieceThermocouple (TWT) method has recently been developed by De Backer. The TWT method is based on thermoelectric effect and allows accurate, fast and industrially suitable temperature monitoring during welding, without the need for thermocouples inside the tool [2]. This paper presents an application of the TWT method for optimisation of the initial weld phases, plunge and dwell, operation in conventional FSW, which can also be applied to friction stir spot welding (FSSW). An analysis of the operation parameters by using feedback temperature control is presented aiming to better control of the initial weld phases through temperature feedback.The introduction of the TWT temperature sensor provides additional process information during welding. Fast data acquisition gives opportunity to differentiate different process phases: contact of probe tip with workpiece surface; plunge phase; dwell phase. This would be followed by tool retraction for FSSW or tool traverse phase for FSW.The effect of the plunge parameters on weld temperature and duration of each phase were studied for the purpose of optimising the process with respect to process (i) robustness, (ii)time, (iii) robot deflection and (iv) quality. By using temperature feedback, it is possible to control the plunge phase to reach a predefined weld temperature, avoiding overheating of the material, which is known to have a detrimental influence on mechanical properties. The work presented in this paper is an important step in the optimization of robotic FSSW and FSW.
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| 20. |
- Silva, Ana, et al.
(author)
-
Cooling rate effect on temperature controlled FSW process
- 2015
-
Conference paper (peer-reviewed)abstract
- A continuous trend towards more demanding jointgeometries is imposed across various manufacturingindustries. During Friction Stir Welding (FSW) of suchcomplex geometries, the surrounding environment playsan important role on the final weld quality, especially inthermal aspects. In order to guarantee a consistent weldquality for different conditions, in-process weldingparameter adaptation is needed.This paper studies the effect of the cooling rate onmechanical properties for temperature controlled FSW byusing different backing bar materials. A new temperaturesensor solution, the Tool-Workpiece Thermocouple(TWT) method [1], was applied to measure thetemperature during welding. A FSW-robot equipped withtemperature and force feedback control was used, whererotation speed was varied to maintain a constant weldingtemperature. AA7075-T6 lap joints were performed withand without temperature control. The cooling rate duringwelding was acquired and macrographs and mechanicalproperties were evaluated for each weld. The rotationspeed offered a fast response promoting the heat inputnecessary to weld at the set temperature. Temperaturecontrolled welds presented a better behaviour undertensile loads. The results prove that temperature controlusing the TWT method is suitable to achieve higher jointquality and provides a fast setup of optimal parameters fordifferent environments.The work presented is an important step in the processoptimization through feedback control which willconsider not only the operational parameters of theprocess as such but also the resulting quality of the joint.
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| 21. |
- Silva, Ana, 1986-, et al.
(author)
-
Temperature measurements during friction stir welding
- 2017
-
In: The International Journal of Advanced Manufacturing Technology. - : Springer. - 0268-3768 .- 1433-3015. ; 88:9-12, s. 2899-2908
-
Journal article (peer-reviewed)abstract
- The increasing industrial demand for lighter, more complex and multi-material components supports the devel-opment of novel joining processes with increased automationand process control. Friction stir welding (FSW) is such aprocess and has seen a fast development in several industries. This welding technique gives the opportunity of automationand online feedback control, allowing automatic adaptation to environmental and geometrical variations of the component. Weld temperature is related to the weld quality and therefore proposed to be used for feedback control. For this purpose, accurate temperature measurements are required. This paper presents an overview of temperature measurement methods applied to the FSW process. Three methods were evaluated in this work: thermocouples embedded in the tool, thermocouples embedded in the workpiece and the tool-workpiece thermocouple (TWT) method. The results show that TWT is anaccurate and fast method suitable for feedback control of FSW.
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| 22. |
- Silva, Ana, et al.
(author)
-
TWT method for temperature measurement during FSW process
- 2015
-
In: The 4th international Conference on scientific and technical advances on friction stir welding & processing. - San Sebastian, Spain. ; , s. 95-98
-
Conference paper (peer-reviewed)abstract
- Friction stir weld (FSW) has generated a high interest in many industry segments in the past 20 years. Along with new industrial challenges, more complex geometries and high quality demands, a better control of the welding process is required. New approaches using temperature controlled welding have been proposed and revealed good results. However, few temperature measurement methods exist which are accurate, fast and industrially suitable. A new and simple sensor solution, the Tool-Workpiece Thermocouple (TWT) method, based on the thermoelectric effect was recently developed.This paper presents a calibration solution for the TWT method where the TWT temperature is compared to calibrated thermocouples inside the tool. The correspondence between both methods is shown. Furthermore, a calibration strategy in different aluminium alloys is proposed, which is based on plunge iterations. This allows accurate temperature monitoring during welding, without the need for thermocouples inside the tool.
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| 23. |
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| 24. |
- Silva-Magalhaes, Ana, et al.
(author)
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A Friction Stir Welding case study using Temperature Controlled Robotics with a HPDC Cylinder Block and dissimilar materials joining
- 2019
-
In: Journal of Manufacturing Processes. - : Elsevier. - 1526-6125 .- 2212-4616. ; 46, s. 177-184
-
Journal article (peer-reviewed)abstract
- The automotive industry is going through a radical transformation from combustion engines to fully electric propulsion, aiming at improving key performance indicators related to efficiency, environmental sustainability and economic competitiveness. In this transition period, it is important to continue the innovation of combustion engines for e.g. plug-in hybrid vehicles. This led Volvo Cars to pursue radically new manufacturing processes such as Friction Stir Welding (FSW). The work presented in this paper is a case study whereby feasibility of using FSW to join a reinforcement element into the aluminium casted Cylinder Block was studied. The complex geometry of the joint required a flexible five-axis manipulator, i.e. an industrial robot, as well as advanced process control, i.e. temperature feedback control, in order to maintain a consistent weld quality throughout the whole component. The process was successfully demonstrated in a lab environment and offers a cost-efficient solution while maintaining the durability and higher efficiency. The outcome of this study shows the great potential of implementing the FSW process in combination with High Pressure Die Casted components, such a Cylinder Block.
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| 25. |
- Silva-Magalhães, Ana, et al.
(author)
-
In-situ temperature measurement in friction stir welding of thick section aluminium alloys
- 2019
-
In: Journal of Manufacturing processes. - : Elsevier. - 1526-6125 .- 2212-4616. ; 39, s. 12-17
-
Journal article (peer-reviewed)abstract
- Friction stir welding (FSW) is a reliable joining technology with a wide industrial uptake. However, several fundamentals of the process such as the temperature inside the stirred zone of the weld and its influence on mechanical properties, are not yet fully understood. This paper shows a method for accurate temperature measurements in multiple locations around the tool, to identify the location of the peak temperature, the temperature variations between the advancing and the retreating side of the tool and its relation to the tool geometry. Both standardised thermocouples in the FSW tool and the novel “tool-workpiece thermocouple” method were used to record temperatures.Bead-on-plate welds in 20 mm thickness AA6082-T6 were produced while the temperatures were measured in three locations on the FSW tool: at the shoulder outer diameter, at the transition from shoulder to probe and at the probe tip. It was found that the hottest point in the stirred zone was 607 °C and was located at the transition between the shoulder and probe, on the retreating-trailing side of the tool. The lowest temperature was found at the probe tip on the retreating-leading side of the tool.The results offer a better understanding of the temperature distribution around a FSW tool. The method presented can be applied to verification of thermal simulation models, tool design optimization, quality assurance and temperature feedback control.
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| 26. |
- Ziada, Osama, et al.
(author)
-
Robotic Window Assembly : A Simulation Study and a Proposed Self-Adaptive Software Architecture
- 2022
-
In: Proceedings of the 10th Swedish Production Symposium. - : IOS Press. - 9781643682709 - 9781643682716 ; , s. 111-121
-
Conference paper (peer-reviewed)abstract
- The key driving factors in using humans and robots in collaborativeapplications for assembly processes are to reduce assembly time, cost and toimprove the human working environment from an ergonomic viewpoint. Currently,there are limited automated procedures in assembly operations in house constructionbecause the traditional type of assembly process depends entirely on manpower.This is common in the assembly process in different industries since assembly isone of the most demanding and intense manufacturing processes, and it is difficultto automate. This paper presents a case study on the implementation of human-robotcollaboration for window assembly by way of an offline robot programmingsimulation. A self-adaptive software architecture that runs on a real-time targetmachine is also proposed for robotic window assembly. The window assemblymethod that will be used in this study is called “Click-In” and is manufactured byFixture System Sweden AB. Apart from robot simulations, detailed suggestions aregiven for building a pilot cell for robot window assembly. The case study presentedin this paper has both economical and ergonomic goals. The economic goal is toreduce the assembly time which will lead to an increase in window production. Byintroducing human-robot collaboration, operators do not need to performuncomfortable assembly operations—rather the robot will perform these unergonomic operations. The feasibility of both goals is verified with offline robotprogramming simulation.
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