Destabilizing effect of Coulomb friction induced limit cycles on sampled-data linear systems

This paper presents a counterintuitive effect of Coulomb friction on the dynamics of sampled-data linear systems. Due to dry friction, the motion becomes sensitive to the initial conditions, and the different possible motion trajectories are separated by limit cycles. This paper shows that the linearly stable behavior of the frictionless case degrades due to the presence of dry friction and how the stable domain of operation decreases. The results are illustrated through the example of a single-degree-of-freedom system model. The presented analysis of the nonlinear system gives insight into the intricate dynamics of sampled-data systems due to the effect of dry friction, and numerical simulations verify the results.