Digital controller design for recordable optical disk player using disturbance observer

One of the most useful applications for an optical disk is a digital still camera (DSC). It is widely recognized that the vibration/shock caused by the motion of these devices is a serious problem for a portable CD (compact disk) or MD (mini disk) player. As far as a DSC with a recordable optical disk is concerned, if is far more important to reduce the effect of the disturbances in order not to fail to write data properly in the presence of even a strong disturbance. In this paper the disturbance observer has been implemented on a new recordable optical disk drive for DSC and some remarkable simulation and experimental results are shown.