Stick–slip oscillations in a multiphysics system

Abstract

This work analyzes a multiphysics system with stick–slip oscillations. The system is composed of two subsystems that interact, a mechanical and an electromagnetic (a DC motor). The mechanical subsystem is subject to a dry frictional force modeled as a Coulomb friction. The resulting motion of the mechanical subsystem can be characterized by two qualitatively different and alternate modes, the stick and slip modes, with a nonsmooth transition between them. The stick–slip oscillations affect and are affected by the electromechanical coupling. To the best of our knowledge, the study of stick–slip oscillations of this kind of system is a novelty in the literature since no references dealing with it were found after an extensive literature review. An analytical approximation of the upper bound for the stick duration is proposed. It should be remarked that the stick duration is one of the variables of great interest in systems with stick–slip dynamics. One the advantages of having the analytical approximation we propose is that it allows the observation of the influence of mechanical and electromagnetic variables and parameters on the stick duration.