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- Olsson, Tomas, et al.
(author)
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Cost-efficient drilling using industrial robots with high-bandwidth force feedback
- 2010
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In: Robotics and Computer-Integrated Manufacturing. - : Elsevier. - 0736-5845 .- 1879-2537. ; 26:1, s. 24-38
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Journal article (peer-reviewed)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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| 2. |
- Stolt, Andreas, et al.
(author)
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Force controlled assembly of flexible aircraft structure
- 2011
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In: Proceedings - IEEE International Conference on Robotics and Automation. - Shanghai, China : IEEE. ; , s. 6027-6032
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Conference paper (peer-reviewed)abstract
- The use of industrial robots in the aircraft industry has been hampered by a combination of poor accuracy of the robots and poor calibration of the workcell, and also manufacturing variability in composite parts. A way to handle these difficulties is using force control. An experimental case where a semi-compliant rib is aligned to multiple surfaces is used as an example to show this. The constraint-based task specification framework is used for the modelling and control, and the search and alignment sequence required for the assembly is modeled with a state machine. An implementation on an industrial robot system is presented and experimental data is evaluated. The described approach is easy to apply to other fields and more complicated assembly operations as well. © 2011 IEEE.
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