| 1. |
- Björkman, Mattias, et al.
(författare)
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A New Concept for Motion Control of Industrial Robots
- 2008
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Ingår i: Proceedings of the 17th IFAC World Congress. - Linköping : Linköping University Electronic Press. - 9783902661005
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Konferensbidrag (refereegranskat)abstract
- This paper gives a short summary of an industrial development work on model-based motion control. This development has resultet in high robot motion performance simultaneously with an efficient use of the installed drive system of the robot.
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| 2. |
- Blomdell, Anders, et al.
(författare)
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Extending an Industrial Robot Controller-Implementation and Applications of a Fast Open Sensor Interface
- 2005
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Ingår i: IEEE Robotics & Automation Magazine. - 1070-9932. ; 12:3, s. 85-94
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Tidskriftsartikel (refereegranskat)abstract
- Many promising robotics research results were obtained during the late 1970s and early 1980s. Some examples include Cartesian force control and advanced motion planning. Now, 20 years and many research projects later, many technologies still have not reached industrial usage. An important question to consider is how this situation can be improved for future deployment of necessary technologies. Today, modern robot control systems used in industry provide highly optimized motion control that works well in a variety of standard applications. To this end, computationally intensive, model-based robot motion control techniques have become standard during the last decade. While the principles employed have been known for many years, deployment in products required affordable computing power, efficientengineering tools, customer needs for productivity/performance, and improved end-user competence in the utilization of performance features. However, applications that are considered nonstandard today motivate a variety of research efforts and system development to package results in a usable form. Actually, robots are not useful for many manufacturing tasks today, in particular those found in small and medium enterprises (SMEs). Reasonsinclude complex configuration, nonintuitive (for the shop floor) programming, and difficulties instructing robots to deal with variations in their environment. The latter challenge includes both task definitions and definition of motion control utilizing external sensors. The key word here is flexibility, and flexible motion control is particularly difficult since the user or system integrator needs to influence the core real-time software functions that are critical for the performance and safe operation of the system. We must find techniques that permit real-time motion controllers to be extended for new, demanding application areas.
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| 3. |
- Crothers, Phil, et al.
(författare)
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Characterization of the Tau parallel kinematic machine for aerospace application
- 2009
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Ingår i: SAE 2009 AeroTech Congress & Exhibition Technical Papers.
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Konferensbidrag (refereegranskat)abstract
- A consortium of interested parties has conducted an experimental characterization of two Tau parallel kinematic machines which were built as a part of the EU-funded project, SMErobot1. Characteristics such as machine stiffness, work envelope, repeatability and accuracy were considered. This paper will present a brief history of the Tau parallel machine, the results of this testing and some comment on prospective application to the aerospace industry.
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| 4. |
- Gunnar, Johan, et al.
(författare)
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Nonlinear Grey-box Identification of Linear Actuators Containing Hysteresis
- 2006
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Ingår i: Proceedings of the 2006 IEEE International Conference on Robotics and Automation. - Linköping : Linköping University Electronic Press. - 0780395050 ; , s. 1818-1823
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Konferensbidrag (refereegranskat)abstract
- A new identification procedure for a linear actuator used in parallel kinematic manipulators has been developed. The actuator dynamics contain both hysteresis and backlash resulting in a highly nonlinear system. The results in this paper show that not only can a nonlinear model of the system be successfully identified from measurement data, but the model is also compact enough to be an ideal candidate for inclusion in a high-performance robot control system.
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| 5. |
- Haage, Mathias, et al.
(författare)
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Reconfigurable Parallel Kinematic Manipulator for Flexible Manufacturing
- 2009
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Ingår i: 13th IFAC Symposium on Information Control Problems in Manufacturing. - 9783902661432 ; 42:4, s. 145-150
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Konferensbidrag (refereegranskat)abstract
- Flexible manufacturing puts high demands on industrial automation in terms of affordable and competitive solutions and is of key importance for short-lot production typically found in small and medium sized enterprises, situations where today manual labour is extensively used despite environmental issues and harsh working conditions. Key factors in the successful introduction of new robot automation concepts are that they provide both the desired performance and quality (technical capability), but also that they enable fast deployment and extend available task repertoire. The Gantry-Tau manipulator is a new robot concept which in contrast to other high-performance parallel kinematic manipulators (PKM), has a large, open working range. Its high stiffness makes it ideal for a wide range of tasks such as grinding, deburring, and cutting. An additional aspect of such a PKM is the modularity, which in this work has been studied in terms of possibilities for assembly and mechanical reconfiguration at the end-user site, integration of such a kinematically different robot with a standard industrial controller, and new needs for methods/tools to support simple (re)configuration. A range of software tools and methods were found to be useful and necessary for efficient engineering and integration of the concept in typical SME manufacturing scenarios. For experimental evaluation, two full-scale prototype robots were designed and built, the kinematic software was developed and integrated into a couple of different robot control systems, robot CAD software was adapted to the configuration needs, and both simulations and physical experiments were carried out. Our findings make us believe that enhanced software tools should be integrated on a higher symbolic (or meta-) level to better support transformation of data and code generation, but also that the Gantry-Tau type of robot (with adequate software support) will bring a new dimension of flexibility into SME manufacturing.
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| 6. |
- Kihlman, Henrik, et al.
(författare)
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On the Use of Force Feedback for Cost Efficient Robotic Drilling
- 2007
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Ingår i: SAE Technical Paper Series. - Los Angeles, CA, US : Society of Automotive Engineers. - 0148-7191.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Drilling is one of the most costly and labour-intensive operations in aircraft assembly. Rather than automating with expensive fixtures and precise machinery, our approach is to make use of standard low-cost robot equipment in combination with sensor feedback. The focus is to eliminate the sliding movement of the end-effector during the clamp-up, called the skating effect, and to keep the end-effector orthogonal to the surface, thus avoiding holes that are not perpendicular. To that end, force feedback is used for building up pressure to clamp up an end-effector to the work-piece surface prior to drilling. The system, including the planning of force parameters for each hole to be drilled, was programmed in DELMIA. The drilling was accomplished with the aid of an extension to the ABB Rapid language called ExtRapid, which is an XML-like code that is interpreted by the force feedback controller downstream in the process. Although experimental results are from drilling, the conceptual idea is believed to be useful in many other applications requiring external sensor feedback control of industrial robots.
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| 7. |
- Nilsson, Klas, et al.
(författare)
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Productive Robots and the SMErobot Project
- 2005
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Ingår i: Book of Abstracts of Third Swedish Workshop on Autonomous Robotics.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The need for keeping manufacturing and workplacesin Europe calls for new ideas and concepts for productiverobots with focus on their usefulness for Small andMedium sized Enterprises (SMEs). The activitiesfrom the Robotics Research at LTH, [3], [4], [2], andin particular those related to the SMErobot project[1] comprise efforts in this direction. The SMErobotproject is a recently started four-year-project of the6th Framework Programme of the EC "to create anew family of SME-suitable robots and to exploit itspotentials for competitive SME manufacturing". Tothis purpose the goal is not to create fully autonomousrobots for all possible tasks, but rather to createsemi-autonomous robots and to allow for human-robotinteraction in a safe way.
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| 8. |
- Pettersson, Marcus, 1977-
(författare)
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Design Optimization in Industrial Robotics : Methods and Algorithms for Drive Train Design
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Robot manufacturers, like many other manufacturers, are experiencing increasing competition in a global market where one way to confront the challenge is by making the development process more efficient. One way to speed up the time to market for new products is to take advantage of design optimization based on simulation models. By optimizing performance with the help of dynamic simulation, an immense amount of both time and money may be saved.In this thesis, design optimization strategies for industrial robot design are studied. Often, the trade-offs between performance, cost and quality are essential for design decisions. These tradeoffs can be investigated with the help of simulation models. Generating the trade-offs can be both cumbersome and time-consuming, but the process may be partly automated with the help of optimization algorithms. How the optimization problem needs to be formulated to generate the trade-off is discussed in this thesis.Robot design problems usually consist of a mixture of deciding continuous parameters as well as selecting components from catalogs and databases. Hence, there is a need for optimization algorithms which can handle variables of both a discrete and a continuous nature. A new method has been developed to address this problem. The method has also been improved by adding adaptive characteristics for further efficient design optimization.The ideas in this thesis have been applied to both simulation models of conceptual degrees of elaboration as well as simulation models of complete robot systems. An optimization procedure which shows how optimization can be used in the early phases of a development process is developed. The objective of the optimization is to determine optimal gearboxes and arm lengths from an acceleration capability perspective. An optimization based design method for robot drive trains is also presented. For further efficient use of already installed robots the concept of application adapted performance optimization is introduced. This means that the robot control is optimized with respect to thermal and fatigue load for the specific program that the robot performs. The motion program itself, i.e. the path planning, can be optimized at the same time in order to get the most out of the robot.
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| 9. |
- Robertsson, Anders, et al.
(författare)
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Implementation of Industrial Robot Force Control Case Study: High Power Stub Grinding and Deburring
- 2006
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Ingår i: 2006 IEEE/RSJ International Conference on Intelligent Robots and Systems (IEEE Cat. No. 06CH37780D). - 1424402581 ; , s. 2743-2748
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Konferensbidrag (refereegranskat)abstract
- In this paper, the results from a joint industry-academia project in industrial robotic force control are presented. The extension and implementation of an external sensor system for an industrial robot system, which can be used for high-bandwidth force control, are described. Results from two industrial applications using the system are presented, a stub grinding application using a new compliant grinding end-effector integrated with the robot control system, and a deburring application with a stiff tool requiring high-bandwidth force control in six degrees of freedom. Using the system an easily reconfigurable control structure was achieved, which was able to control contact forces with a sampling bandwidth of an order of magnitude higher than for conventional robot controllers
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