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- Jonsson, Marie, 1979-, et al.
(författare)
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Development of an automated reconfigurable device for affordable fixturing
- 2011
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Ingår i: Proceedings of the 21st International Conference on Production Research (ICPR2011), 31st July - 4th August, Stuttgart, Germany. - 3839602939 - 9783839602935
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Fixtures are used in manufacturing to hold and position products or workpieces. Linköping University has over a period of several years developed an approach to flexible fixturing that relies on an outer measuring system to ensure accuracy rather than the more common approaches of high internal accuracy or a built-in chain of tolerances. The Linköping system fuses modularity, a rebuildable framework, with reconfigurability, through the means of adjustable devices. To address the need for speed in reconfiguration an automated approach has been developed as a proof-ofconcept. The system consists of electrical motors attached to the legs of the Flexapod 6, a PC, controller cards and an external measuring system. The measuring system feeds information to the PC that is utilized to calculate desired leg length using a Visual Basic program that communicates with CATIA V5. This program then sets signals to the motor controller cards which run the actuators. Due to the motors used the accuracy achieved are in the range of +/-0.15 mm but this may be enhanced with other types of motors developed for higher strengthrather than speed. The system can be further developed by having the actuators as the actual legs of the Flexapod, making it a cheaper Hexapod robot. The paper presents the automated Flexapod 6 in the current system along with possible further development.
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| 2. |
- Kihlman, Henrik, et al.
(författare)
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Flexapods - Flexible Tooling at SAAB for Building the NEURON Aircraft
- 2010
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Ingår i: SAE Technical Paper Series. - 400 Commonwealth Drive, Warrendale, PA, United States : SAE International. - 0148-7191.
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Konferensbidrag (refereegranskat)abstract
- Building prototype aircrafts is costly in tooling especially since only one aircraft is being built. Today's most common tooling strategy is to weld together a beam framework. Welded framework solutions have long lead times both in design and manufacturing and once the aircraft is assembled the tool becomes obsolete. Flexible tooling strategy uses non-welded tooling thus it can be changed and re-used for future products. Early version of a new aircraft model is always hampered by frequent changes in its design, which is cumbersome to handle in a welded framework solution. This paper presents a flexible assembly tooling solutions based on Flexapods and BoxJoint. The Flexapods are commercialized reconfigurable tooling units that are manually adjusted injunction with a laser tracker to a final positional accuracy of +/? 0,05 mm absolute accuracy. An operator software program called the Flexapod control panel collect metrology data in real-time and an operator screen show graphics on how to manually jog the Flexapod joints to reach the final Cartesian 3D-coordinate. The Flexapods are installed in a modular steel based framework solution called BoxJoint. A complete PLM package has been developed for the solution where the Flexapods are configured in CATIA using an add-on package to CATIA called the Flexapod configurator. All CATIA data is stored in ENOVIA. Once the Flexapod fixture is designed in CATIA a file, containing all Cartesian coordinates of the Flexapods, is exported and loaded into the Flexapod control panel on the workshop floor. A previous paper on the Flexapod as an early concept and a paper on BoxJoint have been presented at SAE Aerofast. This paper follows up on these results and presents a case study at SAAB Aeronautics for implementing the first industrial solution of Flexapods to build the military unmanned aerial vehicle - nEURON.
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| 3. |
- Olsson, Tomas, et al.
(författare)
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Cost-efficient drilling using industrial robots with high-bandwidth force feedback
- 2010
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Ingår i: Robotics and Computer-Integrated Manufacturing. - : Elsevier. - 0736-5845 .- 1879-2537. ; 26:1, s. 24-38
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Tidskriftsartikel (refereegranskat)abstract
- Here we present a method for high-precision drilling using an industrial robot with high-bandwidth force feedback which is used for building up pressure to clamp-up an end-effector to the work-piece surface prior to drilling, The focus is to eliminate the sliding movement (skating) of the end-effector during the clamp-up of the end-effector to the work-piece surface, an undesired effect that is due to the comparatively low mechanical stiffness of typical serial industrial robots. This compliance also makes the robot deflect due to the cutting forces, resulting in poor hole position accuracy and to some extent in poor hole quality. Recently, functionality for high-bandwidth force control has found its way into industrial robot control systems. This could potentially open up the possibility for robotic drilling systems with improved performance, using only standard systems without excessive extra hardware and calibration techniques. Instead of automation with expensive fixtures and precise machinery, our approach was to make use of standard low-cost robot equipment in combination with sensor feedback. The resulting sliding suppression control results in greatly improved hole positioning and quality. The conceptual idea behind the force control is useful also in many other robotic applications requiring external sensor feedback control.
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