Abstract
It is known that a quasi-rigid body mode exists in hard disk drives in the frequency range from 3 to 6 kHz and it is caused by the flexibility of the pivot, the mass and structure of the head actuator assembly. The mode hinders performance improvement of servo system in bandwidth. In this paper, a tuned damping device is proposed to suppress this mode. The damping device is to be installed on the arm and hollow space within the voice coil motor on the HDDs. The dynamic characteristics of the head actuator assembly with the tuned damping device are measured in both frequency domain and time domain. It is shown that the tuned damping device can work effectively to suppress the quasi-rigid body vibration of the head actuator assembly and minimize the residual vibration in head positioning.
