Friction Compensation Control to Achieve Pre-specified Transient and Steady-state Performance

A friction compensation control method based on funnel control has been developed that achieves a pre-specified transient and steady-state performance. The proposed control method has the following features: (1) the controller is designed using a backstepping method, (2) the friction characteristic is represented by the LuGre model, (3) the nonlinear characteristic of the LuGre model is approximated by a neural network, and (4) the weights of the neural network are estimated adaptively. To verify the effectiveness of the proposed control method, experiments were performed using a positioning stage. As a result, it was confirmed that the proposed control method could achieve the pre-specified transient and steady-state performance even when the dynamic behavior of nonlinear friction changed.