Controlling Vibration of HDD Actuator by Using Dummy Heads

Abstract

Some hard disk drives (HDDs) have fewer than the maximum number of magnetic heads. Such HDDs need to be re-designed to keep their position accuracy. We focused on adding dummy heads instead of re-designing the whole actuator. A dummy head is put on the edge of an arm model, and it influences the vibration characteristics of the model. Because the vibration characteristics of the arm model are related to those of the whole actuator, we optimized the dummy head design by focusing on the vibration characteristics of a local arm model instead of focusing on the whole actuator. We created a dummy head that would enable HDDs to keep the gain of their vibration characteristics around the sampling frequency as low as those of an HDD with the maximum number of mountable magnetic heads.