A novel method of adaptive repetitive control for optical disk drivers

Abstract

In optical disk drives, which support various speeds, it is not avoidable to have a varying periodic disturbance. However, it is still possible to control optical disk drives by using a controller which repeatedly control the drive to change sampling frequency to follow the change of reference period. This paper introduces an adaptive repetitive control method to attenuate the periodic disturbances. The proposed adaptive repetitive control is built with two parts, the repetitive controller and the frequency multiplier. The repetitive controller uses a varying sampler operating at a variable sampling rate maintained at fixed multiple times of the disturbance frequencies and the frequency multiplier generates the varying sampling frequencies based on the disturbance frequency. © Springer-Verlag Berlin Heidelberg 2006.