Consideration of robot rigidity in roller heming processes

The paper shows experimental results of quality features (e.g. roll-in, hem thickness) of a representative hemming specimen in relation to varying robot system stiffnesses resulting from different hemming locations. Deviations from the nominal roller path to the real roller path in different locations are analysed by the application of an optical measurement system. Furthermore, a method for a simulative estimation of the robots stiffness along different hemming paths on the basis of a multibody simulation is being introduced. The quality of that estimation is compared to experimental measurements. Finally, the estimated system stiffness along the hemming path is implemented into a numerical FE-simulation showing a substantial improvement of the simulation quality.