Chaotic motion of dry friction systems with multi-scale stick-slip characteristics

Multi-scale stick-slip dry friction at contact interface plays a significant role in the nonlinear system dynamics. The classic coulomb friction model cannot reflect the complex dry friction phenomenon accurately. So, a dry friction system with multi-scale stick-slip characteristics was proposed. A displacement-based Iwan hysteretic constitutive model was used to model the interface friction. The equation of motion was established and the numerical solution of the system under harmonic excitation was obtained with the central difference method. The steady state dynamic response was obtained under 1:1 and 1:2 resonance condition. It is shown that, in the case of 1:1 resonance, the dynamic behavior is extremely sensitive due to the existense of transversal heteroclinic point, and the double-periodic motion and chaos will happen along with the variation of characteristic parameters. In the case of 1:2 resonance, there are infinite homoclinic points, and chaotic motion may emerge under small perturbations.