Detection of surface defects and servo signal restoration for a compact disc player

Compact disc (CD) players have been on the market for more than two decades, and the involved technologies, including control are very mature. Some problems, however, still remain with respect to playing CDs having to surface defects like scratches and fingerprints. Two servo control loops are used to keep the optical pick-up unit (OPU) focused and radially locked to the information track of the CD. The problem is to design servo controllers which are well suited for both handling surface defects and disturbances like mechanical shocks. The handling of surface defects requires a low-controller bandwidth which is in conflict with the requirement for the handling of disturbances. This control problem can be solved by the use of a fault tolerant control strategy, where the fault detection is very important. The OPU feeds the controllers with detector signals. Based on these, focus and radial distances can be estimated and a pair of residuals can be computed. This paper introduces a model-based method to estimate focus and radial distances as well as residuals, which have the potential to improve the control of a CD player in case of a surface defect. The methods are applied to experimental data of a scratch. The results of this experimental work show the potential of the method.

[1]  Jia-Yush Yen,et al.  Servo controller design for an optical disk drive using fuzzy control algorithm , 1992, [1992 Proceedings] IEEE International Conference on Fuzzy Systems.

[2]  William F. Coscarelli,et al.  The Compact Disc Handbook , 1994 .

[3]  K. Schouhamer Immink,et al.  Principles of Optical Disc Systems , 1985 .

[4]  Ting-Jen Yeh,et al.  Modeling and identification of opto-mechanical coupling and backlash nonlinearity in optical disk drives , 2000, IEEE Trans. Consumer Electron..

[5]  H. F. Mikkelsen,et al.  Modelling of the optical detector system in a compact disc player servo system , 2003, Proceedings of the 2003 American Control Conference, 2003..

[6]  J. Stoustrup,et al.  Fault residuals for compact disc players based on redundant and non-linear sensors , 2004, Proceedings of the 2004 American Control Conference.

[7]  Leehter Yao,et al.  Track seeking hybrid fuzzy controller for the compact disc player , 2001, 10th IEEE International Conference on Fuzzy Systems. (Cat. No.01CH37297).

[8]  M Maarten Steinbuch,et al.  Robust control of a compact disc player , 1992, [1992] Proceedings of the 31st IEEE Conference on Decision and Control.

[9]  Ken C. Pohlman.  The compact disc handbook (2nd ed.) , 1992 .

[10]  M. Dettori,et al.  LMI Techniques for Control - with application to a Compact Disc player mechanism , 2001 .

[11]  G. Hearns,et al.  Limits of performance of an optical disk drive controller , 1999, Proceedings of the 1999 American Control Conference (Cat. No. 99CH36251).

[12]  Palle Andersen,et al.  Linear quadratic controller with fault detection in compact disk players , 2001, Proceedings of the 2001 IEEE International Conference on Control Applications (CCA'01) (Cat. No.01CH37204).

[13]  Masayoshi Tomizuka,et al.  Digital tracking controller design for CD player using disturbance observer , 1998, AMC'98 - Coimbra. 1998 5th International Workshop on Advanced Motion Control. Proceedings (Cat. No.98TH8354).

[14]  Maarten Steinbuch,et al.  Adaptive control of the radial servo system of a compact disc player , 1992, Autom..

[15]  S. Stan.  The CD-ROM Drive , 1998 .

[16]  Palle Andersen,et al.  Open and closed loop parametric system identification in compact disk players , 2001, Proceedings of the 2001 American Control Conference. (Cat. No.01CH37148).

[17]  P.M.J. Van den Hof,et al.  Adaptive repetitive control of a compact disc mechanism , 1995, Proceedings of 1995 34th IEEE Conference on Decision and Control.

[18]  Gene F. Franklin,et al.  Digital control of dynamic systems , 1980 .

[19]  J. Stoustrup,et al.  A study on the surface defects of a compact disk , 2001, Proceedings of the 2001 IEEE International Conference on Control Applications (CCA'01) (Cat. No.01CH37204).

[20]  Jintai Chung,et al.  Vibration and noise reduction of an optical disk drive by using a vibration absorber , 2002, IEEE Trans. Consumer Electron..

[21]  Tsu-Chin Tsao,et al.  Rejection of repeatable and non-repeatable disturbances for disk drive actuators , 1999, Proceedings of the 1999 American Control Conference (Cat. No. 99CH36251).

[22]  W T Welford,et al.  Principles of Optical Disc Systems , 1986 .

[23]  M. Steinbuch,et al.  Multivariable control of a compact disc player using DSPs , 1994, Proceedings of 1994 American Control Conference - ACC '94.

[24]  P.F. Odgaard,et al.  Time localisation of surface defects on optical discs , 2004, Proceedings of the 2004 IEEE International Conference on Control Applications, 2004..

[25]  Siri Weerasooriya,et al.  Discrete-time LQG/LTR design and modeling of a disk drive actuator tracking servo system , 1995, IEEE Trans. Ind. Electron..