Abstract
This paper proposes the new realization method of error-prediction control system based on ZPET control and robust feedback control. The error-prediction control system based on ZPET control can reduce the tracking error caused by periodic disturbance compared with general repetition control. However, the proposed tracking servo system does not reduce the residual tracking error cased by the low-pass filter at the feedforward compensation and long sampling time. In order to overcome this problem, this paper proposes the new structure of the feedforward tracking control system. The modified ZPET control tracking servo system for optical disc recording system does not include the low-pass filter and its sampling time becomes faster. On the other hand, the sudden disturbance observer reduces the influence of non-periodic disturbance. The experimental results point out that the proposed tracking servo system has a precise tracking response against both the periodic disturbance and the non-periodic disturbance.
