130 J. Eur. Opt. Society-Rapid Publ. 21, 12( 2025)
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8. Kinematic comparison in freeform grinding experiments showing resulting surface topographies after fine grinding( D30), measured by WLI:( A) feed direction vertical to tool inclination angle and( B) feed direction parallel to tool inclination angle.
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Figure 9. Comparative schematic representation of topography generation during lateral and face grinding:( A) lateral surface grinding with exemplary protruding grains resulting in linear scores and( B) face grinding with exemplary protruding grains resulting in a more statistically distributed surface structure.
speed of individual grains also differ. In this case, all the paths of the grains overlap to a certain extent, which results in a relatively statistically distributed surface structure( Fig. 9( B)). It can be stated that the parallel kinematics are therefore advantageous for avoiding this described form of medium-frequency, periodic defect structures representing the path distance and thus producing a more homogeneous surface.
In order to obtain an overview of the entire component surface, a stitching measurement was carried out using WLI. Once again, a form subtraction was carried out using a fitted third-order polynomial, which allowed an error topography to be visualized, showing low- and mediumfrequency deviations and structures. In addition to other minor surface deviations, two dominant types of grinding structures are shown in Figure 10. Medium-frequency ripple structures aligned vertically to the tool feed direction occurred on the entire surface. In addition, a characteristic“ arch structure” was apparent.
After carrying out various iterative parameter and machine setting variations, a cause for the arch structure was identified and corrected. The arch structure is