Some Experimental and Analytical Results on Self-Excited Vibration of a Dynamic Sliding System in the Case of Stribeck Law for Friction Coefficient

The principal aim of this paper is to deal with friction-induced self-excited vibrations in the context of Stribeck law for friction coefficient. More precisely, the theoretical dynamic system under study consists of a single-degree-of-freedom mass-spring-damper oscillator subjected to a velocity-dependent frictional force as it slides on a conveyor belt, following a Stribeck law. We have analyzed the local stability of the static equilibrium and described the created periodic cycle using the averaging method. Numerical continuation with Matcont software is also used for qualitative analysis of this non linear system. In order to validate the theoretical analysis, an original experimental device, the named Lug test rig developed in our laboratory, was employed. For a glass/elastomer contact lubricated with water, friction force and dynamic displacement have been measured. The appearance of the instabilities is explained in relation to the friction measurements.