Repetitive learning control and its application to a class of nonlinear systems

A new repetitive learning control method based on steady-state response is proposed for the tracking or rejection of unknown periodic reference or disturbance with a known period. It is essentially a feedforward approach and has the merits of high accuracy, easy implementation and insensitive to non-repetitive disturbances, compared with the conventional repetitive control method. Then the proposed method is applied to a class of nonlinear systems, where the disturbances have nonlinear dependency on the output with only continuous Lipschitz condition imposed, which can address most cases in practice. The effectiveness of the proposed method is confirmed by simulation results