Determination of viscous and Coulomb friction by using velocity responses to torque ramp inputs

Reports the results of an experimental study conducted on a direct-drive motor to evaluate the predicted behavior of selected friction models. We focus the study on the velocity response when torque ramp inputs are employed. Among the considered friction models, the dynamic friction model, the so-called LuGre model, captures very well the experimental behavior. As a consequence of the study, we derive a simple procedure to determine the viscous and Coulomb friction from experimental velocity responses