TU. C CD 7
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Godding, Robert
N
0.6 0.6
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= N =
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minor strain q, [-] minor strain q, [-]
Figure 11: FLD (calculated from measured data) and FLC Figure 12: FLD (FEM-simulation)
6 CONCLUSION
The quality of a car body is substantially determined by the stamping parts. This results in increased requirements on
the accuracy of the stamping parts produced in press shops. However, these requirements can only be fulfilled by an
optimal layout of the forming process and a 100% quality control in the press shops both during the tool try-out and
during the production by means of optical measuring techniques.
Therefore, a new photogrammetric measuring system for the assessment of sheet metal parts in terms of shape accuracy
and strain distribution has been developed within the Brite/EuRam project “DIGIMAN”. Based on the optically
measured geometric parameters of the stamping part the system is able to detect deviations from the desired geometry
with springback analysis and critical strain distributions utilizing visioplasticity. A first prototype was installed at the
Institute for Metal Forming and Metal Forming Machine Tools (IFUM) of the University of Hanover. In the future it is
planned to implement further industrial photogrammetric systems for the measurement of large-size outer-body panels
with adequate accuracy in press shops at different car manufactures and producers of sheet metal parts.
ACKNOWLEDGMENTS
Parts of this research work were funded by the European Community within the Brite/EuRam project BE-4798
“Digital Imaging Techniques for Surface Quality Assessment in Manufacturing Industry (DIGIMAN).
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International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B5. Amsterdam 2000. 297
