Prestiction Friction Modeling and Position Control in an Actuated Rotary Arm

In this paper, using experiment and theory, we study the dynamic characteristics of a rotary single-link arm in free motion when the effect of hub friction is significant. Our objective is to identify the important phenomena that affect the system using an adequate friction model. We introduce a friction regime, called ¿prestiction,¿ and a friction model for capturing this regime. Comparisons are made with the LuGre friction model, and the effectiveness of the proposed model for friction compensation is examined in an experimental position control system.