抄録
This paper describes a new head positioning mechanism of a magnetic disk storage. The new positioning mechanism is designed on the basis of the concept of the in-phase positioning mechanism. It has two voice coil motors ; one is a conventional VCM, main-actuator, and the other is a small VCM, sub-actuator, attached on the middle of the arm. Generally, such a dual-actuator system must be driven with two controllers, however, the proposed positioning mechanism requires only one controller for a zero-residue condition of the main-resonance. The way to control the proposed positioning mechanism is called cooperative control. In order to clarify the validity of the proposed positioning mechanism and the cooperative control, a H_∞ controller is designed and applied to the system. A 1.2kHz servo-bandwidth is obtained for 20kHz sampling frequency in a numerical example.
