Sliding susceptibility of a rough cylinder on a rough inclined perturbed surface

A susceptibility function $\chi (L)$ is introduced to quantify some aspects of the intermittent stick-slip dynamics of a rough metallic cylinder of length $L$ on a rough metallic incline submitted to small controlled perturbations and maintained below the angle of repose. This problem is studied from the experimental point of view and the observed power-law behavior of $\chi (L)$ is justified through the use of a general class of scaling hypotheses.