Noise-induced kink propagation in shallow granular layers

•Random fluctuations induce the propagation of the domain wall in a granular layer, macroscopic Brownian motor.•Experimentally, noise-induced kink propagation on a one-dimensional shallow granular layer subjected to an airflow oscillating in time.•Domain wall dynamic is modeled using a simple Langevin equation that described the pinning-depinning transition.•A Gaussian-like distribution in the domain wall displacements and flat power spectrum density are characterized for all the inclinations.