An improved method for determining rough surface parameters based on moving reference line

Abstract Accurate characterization of the measured surface profile is crucial for the calculation and analysis of real surface contact. This study introduces a model that approximates the original profile using a quadratic function, referred to as the deterministic method. Based on the height ratio criterion of asperity peaks to valleys, a moving reference line strategy is further proposed to enhance the accuracy of profile simplification and to determine the corresponding contact characteristic parameters. Characteristic parameters calculated via deterministic and spectral moment methods are integrated into typical micro-contact models to examine the rough surface contact performance, with particular focus on the real contact area and the contact load. The results demonstrate that the proposed improved method enhances the accuracy of rough surface topography characterization. Greater stability under low sampling intervals is observed in the deterministic method relative to the spectral moment method, indicating reduced sensitivity to sampling interval variation.