Robust tracking servo system considering force disturbance for the optical disk recording system

Abstract

This paper proposes a new robust servo system for the optical disk recording system with feedforward controller based on the prediction of the error. In optical recording systems, the feedback servo system must suppress the influence of force disturbance and parameter variation. To overcome this problem, this paper designs the robust feedback control system by using coprime factorization and disturbance observer. The detecting signal of the optical disk recording system is only a error. Hence, the feedforward controller of the proposed control system is constructed based on both the zero-phase-error tracking control theory and the prediction of the error. The experimental results point out that the proposed servo system has a quick and precise response and keeps the residual error below its tolerance.