Robust feedforward track following control system for an optical disk drive system

This paper proposes a new feedforward tracking servo system for optimal disk recording system based on prediction of tracking error. In the optical disk recording systems, its detecting signal is only a tracking error. The tracking servo system, such as CD-R, must have the complete tracking response whose error is less than 0.1[μm] of position reference. For this purpose, this paper proposes a new tracking servo system based on prediction of tracking error. The proposed robust feedforward tracking control system is constructed both "zero phase error tracking" (ZPET) control system and robust feedback control system. Moreover, this paper considers the saturation of controller input. The experimental results point out that the proposed system has a quick and precise tracking response and keeps the residual tracking error below this tolerance smoothly and stably.