Adaptive and robust motion control in presence of LuGre-type friction

The proposed approach to the adaptive motion control in the presence of LuGre-type friction consists in the compensation of all components containing the internal model variable by a robust control term, based on a special “bounding function”. To minimize the chattering effect, this function is approximated by a linear-in-parameters model. The model is tuned on-line by the adaptive control, together with the remaining unknown parameters.