Track following Control with DFT Estimator for Eccentric Error Compensation of Optical Disk Driver

This paper proposes a dynamic eccentric error compensation architecture for the tracking follow controller of optical disk drivers. For enhancing the tracking performance in an optical disk drive servo system, it is essential to attenuate periodic disturbances which are caused by revolutions of the disk. Periodic disturbances can be attenuated using a discrete Fourier transform estimator with the known disturbance frequency provided by a motor driver. Optical disk drivers support various speeds. So optical disk drivers have a varying periodic disturbance. To deal with time varying periodic disturbances, a proposed eccentric error compensation controller is turned based on sinusoidal generator to follow the change of reference period. The disturbance estimator uses the discrete Fourier transform method that models the periodic disturbance. We present simulative and experimental results and show that the proposed control scheme enables a significant improvement of the tracking accuracy of the radial servomechanism and the random access time. We implement the proposed eccentric error controller on the system on chip (SOC).