Robot-Based Incremental Sheet Metal Forming – Increasing the Geometrical Complexity and Accuracy

Abstract:

The industrial application of incremental sheet metal forming is still limited by certain constraints, e.g. low geometrical accuracy and geometrical complexity. In order to overcome these constraints, this paper presents two approaches which have been carried out within the research project Development of a robot-based dieless incremental sheet metal forming process funded by the German Research Foundation (DFG). The first approach increases the geometrical accuracy by adding an addendum stabilization surface. As neither a partial nor a full die is used in this universal concept, there is a larger influence of the free compliant sheet area surrounding the formed part of the geometry. Thus the sheet shifts away from the forming tool more easily, which often results in a less accurate forming. The addendum stabilization surface reinforces this free sheet area. Experiments have proven this to be as good as a partial die. Especially the subsequent deformation resulting from the interaction of differently shaped elements causes geometrical deviations which are limiting the scope of formable parts. The second approach is based on the subsequent forming of elements belonging to the original geometry, which helps to increase the geometrical accuracy as well as the geometrical complexity. Thus the basic geometry is formed in a first step. Afterwards, further elements are formed subsequently, while the adjacent areas are supported by a peripheral supporting tool which prevents their deformation.

• Periodical: Key Engineering Materials (Volume 549)
• Pages: 149-155
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.549.149
• Online since: April 2013
• Authors: Bolko Buff, Christian Magnus, Jun Hong Zhu, Horst Meier
• Keywords: Accuracy, Forming, Robot, Sheet Metal

References

[1] J. Jeswiet, F. Micari, G. Hirt, A. Bramley, J. Duflou, and J. Allwood, "Asymmetric single point incremental forming of sheet metal," CIRP Annals - Manufacturing Technology, vol. 54/2, p.88–114, 2005.

DOI: 10.1016/s0007-8506(07)60021-3

[2] J. Jeswiet, M. Geiger, U. Engel, M. Kleiner, M. Schikorra, J. Duflou, R. Neugebauer, P. Bariani, and S. Bruschi, "Metal forming progress since 2000," CIRP Journal of Manufacturing Science and Technology, vol. 1, p.2/17, 2008.

DOI: 10.1016/j.cirpj.2008.06.005

[3] H. Meier, V. Smukala, O. Dewald, and J. Zhang, "Two-point incremental forming with two moving forming tools," Key Engineering Materials, vol. 344, p.599–605, 2007.

DOI: 10.4028/www.scientific.net/kem.344.599

[4] M. Bambach, "Process strategies and modelling approaches for asymmetric incremental sheet forming," Ph.D. Dissertation, RWTH Aachen, 2008.

[5] R. Malhotra, C. Jian, R. Feng, V. Kiridena, Z. C. Xia, and N. V. Reddy, "Improvement of geometric accuracy in incremental forming by using a squeezing toolpath strategy with two forming tools," Journal of Manufacturing Science and Engineering, vol. 133; Jg. 2011, no. 6, p.10, 2011.

DOI: 10.1115/1.4005179

[6] J. Duflou, J. Verbert, Y. Tunckol, F. Gelaude, and B. Lauwers, "Customised medical implant production by means of single point incremental forming," ICMEN, International Conference on Manufacturing Engineering and EUREKA Brokerage Event, 2; S. 217-225, vol. 2, p.217–225, 2005, ISBN: 960-243-614-X.

[7] A. Governale, A. Lo Franco, A. Panzeca, L. Fratini, and F. Micari, "Incremental forming process for the accomplishment of automative details," Key Engineering Materials, vol. 344, p.559–566, 2007.

DOI: 10.4028/www.scientific.net/kem.344.559

[8] D. Kreimeier, B. Buff, C. Magnus, V. Smukala, and J. Zhu, "Robot-based incremental sheet metal forming - increasing the geometrical accuracy of complex parts," Key Engineering Materials, vol. 473, p.853–860, 2011.

DOI: 10.4028/www.scientific.net/kem.473.853

[9] J. R. Duflou, J. Verbert, B. Belkassem, J. Gu, H. Sol, C. Henrard, and A. M. Habraken, "Process window enhancement for single point incremental forming through multi-step toolpaths," CIRP Annals - Manufacturing Technology, vol. 57, p.253–256, 2008.

DOI: 10.1016/j.cirp.2008.03.030

[10] G. Hirt, J. Ames, M. Bambach, R. Kopp, and R. Kopp, "Forming strategies and process modelling for cnc incremental sheet forming," CIRP Annals - Manufacturing Technology, vol. 53, no. 1, p.203 – 206, 2004.

DOI: 10.1016/s0007-8506(07)60679-9

[11] D. Kreimeier, B. Buff, C. Magnus, V. Smukala, and J. Zhu, "Robot-based incremental sheet metal forming – increasing the geometrical accuracy of complex parts," Presentation: 14th International Conference on Sheet Metal, Leuven, 18-20 April, 2011.

DOI: 10.4028/www.scientific.net/kem.473.853

[12] S. Tanaka, K. Hayakawa, and T. Nakamura, "Incremental sheet forming with direction control of path planes," steel research international, Special Edition: 10th International Conference on Technology of Plasticity, vol. ISBN 978-3-514-00784-0, p.503–507, 2011.