Control of Optical Disc Drive using Sliding Regulator

Abstract

For position control applications such as hard disc drives or optical disc drives, conventional linear controllers with time varying position references result in overshoot or windup by large disturbances or model errors. Instead, mode switching control which consists of velocity control and position control is commonly used, still it has a transient response problem around the switching.
This paper presents a new position control algorithm based on sliding mode control without the conventional switching model. By changing the control structure from velocity control to position control gradually along the optimal nonlinear sliding manifold, the controller gives the system quick settling and robustness. This idea is applied to DVD-optical disc drive seek-following servo system. The improved features are shown by 16bit DSP model base precise simulation.