Accommodation of Repetitive Sensor Faults— Applied to Surface Faults on Compact Discs

Surface defects such as scratches and fingerprints on compact discs (CDs) can cause CD players to lose focus and tracking on the discs. A scheme for handling these defects has previously been proposed. In this brief, adaptive and predictive versions of this scheme are developed. The adaptive scheme can be used to adapt the accommodation to specific surface defects on specific discs, while the predictive scheme can be used to jump between tracks with surface defects on the disc. Sufficient and necessary stability conditions for the proposed accommodation schemes are derived as well. Performance of the accommodation scheme is discussed. Both proposed methods show their potentials through simulations with a CD player playing a CD with a surface defect (scratch).