Stick-Slip Friction

In this example, Stateflow is employed to represent the actual physical states of a system. That is, the friction force exerted between two surfaces is intrinsically tied to their instantaneous relative motion. While at rest, or with zero relative velocity, the force is purely a function of the externally applied forces. With the onset of relative motion, however, an opposing force is generated as a function of the normal force and coefficient of friction. Simulink provides a powerful tool for the conventional dynamics, but Stateflow is a natural and intuitive setting for modeling the physical states. This phenomenon will be present, to a greater or lesser degree, in all mechanical systems.