Tillage Quality Measurement: Surface Roughness Analysis using Height Profiles

Surface roughness is a critical factor during the tillage process, as it impacts soil erosion, hy-drological mechanisms, and seedbed preparation. However, surface roughness can be de-scribed using various parameters, such as root mean square height or mean upslope depres-sion index, which complicates the selection of the most appropriate parameter for measuring tillage process quality. This paper presents an approach to determine the most relevant pa-rameters for measuring surface roughness for the tillage process with a cultivator. The ap-proach consists of three steps. First, surface height profiles are generated in a simulation en-vironment. Second, we evaluate different roughness parameters and analyze them using Spearman’s rank correlation coefficient. The analysis results in parameter clusters that exhibit similar correlations and thus likely describe similar physical properties. Based on this classifi-cation, appropriate parameters are selected. Finally, we compare the simulation environ-ment's correlation matrix with the field trial data correlation matrix. The results indicate that Rqx, Rqy, and Sq are the best parameters for characterizing surface roughness at the aggre-gate level during tillage with a cultivator. ... mehrThese parameters are computationally efficient and provide comprehensive information about the roughness for slope- and anomaly-free data.