Linear quadratic Gaussian controller design for DVD track following

This paper considers the implementation of compensators for periodic disturbance cancellation, specifically applied to the removal of repeatable runout(RRO) from the position error signal(PES) in the high performance DVD player. The internal model principle is used for rejecting the sinusoidal disturbance caused by eccentric rotation of the disk, and the LQG methodology is used for the servo compensator design to improve the drive performance and meet the stability-robustness specifications in the frequency domain. A mathematical model of radial servo is constructed which forms the basis of a computer simulation. Simulation results are presented to show that LQG design is a viable approach.