ABSTRACT
This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book proposes fundamental controller designs based on classical control theories and their extensions. It describes several ultra-fast motion control design methods based on advanced control theories and discusses several ultra-precise position control designs based on advanced control theories. Hard Disk Drive (HDD) servo control is a simple Single-Input-Single-Output system, where the magnetic Read/Write (R/W) head is moved to a target data track in miliseconds and positioned on the track with nanometer accuracy. In an HDD, one or more disks are stacked on the spindle motor shaft and rotate typically at 15,000 revolutions-per-minute in high-performance HDDs and 5,400–7,200 rpm in mobile or desktop HDDs. The basic function of the HDD is to store and retrieve user data on a disk using only one magnetic R/W head, which makes its cost very low.
