Influence of damper position on multi-arm actuator resonance in HDD

Recently, actuator arms in hard disk drive (HDD) have been rapidly developed. However resonance problem of HDD emerges to be a concerning issue because the HDD package is required to be smaller but data capacity must be higher. As a result, the actuator arm is developed to have multiple layers and its characteristic, i.e. natural frequency respond, becomes more complex for either minimizing or shifting. This paper proposes to study resonant frequency of the multi-arm actuator by applying the finite element and the simplified methods. It is found that resonant frequency of the multi-arm actuator measured by LDV and predicted by FEM are consistent.