On the Improvement of Variations in Producing Magnetic Heads Using Tracking Control

In hard disk drive manufacturing, the lapping process is a key procedure to produce high quality magnetic heads. In a lapping machine, an appropriate amount of force will be applied to lap a slider bar until reaching the target. A tilt angle can be adjusted to get an alignment between the secondary element and the primary element. The technique of tuning the tilt angle is provided in this paper. The behavior of lapping is first studied to approximate the desired path. The tracking control is then designed based on a classical control technique to follow the path. The experiments were carried out to show the effectiveness of the control scheme.