Electromagnetic and mechanical control of slip: laboratory experiments with slider system

Field and laboratory data reveal the possibility of a significant coupling of elastic and electromagnetic (EM) fields that affect (hamper or initiate) slip. In this work we try to prove experimentally the possibility of controlling the slip regime by relatively weak mechanical or EM impact, in the way it has been done in nonlinear dynamic experiments on the control of chaos. The experimental setup consisted of a system of two plates of roughly finished basalt, where a constant pulling force was applied to the upper (sliding) plate. In addition, the same plate was subjected to mechanical or electric periodic perturbations, which are much weaker when compared to the pulling force. Quite different regimes of slip were excited depending on the amplitude and the frequency of applied weak perturbations. The observed regimes of slip vary from perfect synchronization of slip events, recorded as acoustic emission bursts with the perturbing periodic mechanical or EM impact, to their complete desynchronization. We consider the obtained results as evidence that it is possible to control slip by the application of weak periodic perturbations. The phenomenon can be explained in terms of nonlinear dynamics and synchronization theory.