Seeking Control of Hard Disk Drive by Perfect Tracking Using Multirate Sampling Control

Abstract

In this paper, novel multirate two-degree-of-freedom controllers are proposed for digital control systems, where it is restricted that the speed of the A/D converters are slower than that of the D/A converters. The proposed feedforward controller assures the perfect tracking at M inter-sampling points. Next, the proposed method is extended to systems with time delay. The proposed scheme is applied to the seeking control for hard disk drive, and advantages of this approach are demonstrated.