A parametric method to quantify the balance of groove sets of honed cylinder bores

The honing texture of gray iron cylinder bores of combustion engines mainly consists of two sets of approximately parallel, stochastically placed grooves at different angles to the cylinder axis. Oil consumption, longevity and noxious emissions highly depend on the quality of this groove texture, that is still often rated by visual inspection of microscopic images by an expert. This approach is tedious and subjective. Therefore it is desireable to develop methods which allow an objective, reproducible and automatic assessment of the honing texture, Within our paper we focus On one important aspect of the boning texture. A method for an objective quantification of the balance of the two groove sets is presented. The sees are compared with respect to their spatial groove densities, amplitudes, widths and angle deviation, A parametric, well-interpretable measure D is constructed that explicitely evaluates the discrepancy between both groove sets on the basis of their propability density functions regarding amplitudes, widths and locations. Additionally, a heuristical measure for the dispersion of the groove angles within each set is taken into account. We show the usefulness of the proposed approach by assessing synthetic textures and a series of red honing textures which are visually rated by experts. Small values of D are sufficient as well as necessary for a balanced appearance of a texture. Moreover, we analyze the statistical reliability of the measure with respect to the size of the observed texture area.