Improved performance of hard disk drive servomechanism using digital multirate control

Abstract

The main objective of the research is to study the advantages achieved through the use of a multirate control in hard disk drive servomechanism, and to design a multirate controller for the systems. Reduced cost plays an important role to keep the manufacture competitive. Compensator of low complexity is advantageous for failure anaylsis. In particular, the thesis introduces number of newly proposed techniques for designing low order and efficient controllers for multirate systems :- 1. Single input single output approach for multirate design, 2. Robust feedforward controller for systems with multiple flexible modes, 3. Partial estimation approach for dual input single output systems and 4. Multirate control for dual stage actuated systems. Simulation and experimental results show that proposed multirate control and compensators perform better for both single-actuated and dual actuated systems.