Nonlinear dynamics of a coupled system with dry-friction

Abstract

This work analyzes the nonlinear dynamics of a coupled system with dry-friction. The system has a mechanical part and an electromagnetic part. It is composed of a cart, whose motion is excited by a DC motor. The coupling between the motor and the cart is made by a mechanism called scotch yoke, so that the motor rotational motion is transformed in horizontal cart motion in a rail. It is considered the existence of dry-friction between the cart and the rail. The friction is modeled as Coulomb friction. The resulting motion of the motor can be characterized by two qualitatively different and alternate modes, the stick-and slip-modes, with a non-smooth transition between them. The focus of the work is to find the stick-and slip-mode parts of the trajectory for different values of the system parameters.