Disturbance Suppression in Feedback Error Learning Control

Feedback error learning is an adaptive control scheme in the two-degree-of-freedom structure. We design a fixed feedback (FB) control law in advance to stabilize the closed-loop, and tune feedforward (FF) control online to improve response to command signals. However, the scheme is not robust against unknown disturbances. This paper proposes a method to address this issue, by introducing an offset term in the tunable FF controller. Furthermore, numerical simulation has been carried out to verify the effectiveness of the proposed method.