AN IDENTIFIABLE CONTROL-ORIENTED DYNAMIC FRICTION MODEL

A new dynamic model to describe friction forces between two bodies in contact is presented. This model is an extension of the popular LuGre dynamic friction model. The main difference is in the description of the Stribeck effect, that now is modeled with a first order nonlinear differential equation. This yields a second order dynamic friction model that still preserves the intuitive base of previous models, reproduces the pseudo-steady state behavior and offers the same input-output properties. The advantage with respect to other dynamic friction models is in the possibility of identifying all the relevant parameters. This is particularly important when these parameters change with time making it difficult to continuously calibrate the model.