Influence of range measurement noise on roughness characterization of rock surfaces using terrestrial laser scanning

The application of laser scanning in studying rock surfaces is limited by the range measurement noise inherent in the laser scanner data. In this paper we investigate the influence of range measurement noise on the quantification of rock surface roughness. Roughness measures derived from the laser scanner data are compared with those derived from manual measurements. The comparison shows that the presense of noise in range measurements leads to an overestimation of the fractal dimension and amplitude of roughness profiles. Experiments with wavelet decomposition and thresholding methods for reducing noise in the laser range data are presented. The results indicate that wavelet de-noising methods in general lead to more realistic estimates of the roughness of the laser profiles.

► Roughness profiles extracted from laser range data contain noise.
► Presence of noise results in an overestimation of roughness measures.
► Effect of noise is larger on roughness profiles with smaller fractal dimension and amplitude.
► Wavelet de-noising of laser profiles leads to more realistic estimates of roughness measures.