A New Adaptive Method for Identification of Multiple Unknown Disturbance Frequencies in HDDs

In hard disk drive (HDD) system, disturbances like rotary vibrations and shocks usually contain frequency components with time-varying phases and magnitudes. The effect of these disturbances has to be attenuated for better servo performance, and the dominant frequencies of these disturbances need to be estimated. In this paper, a new adaptive identification method for frequency estimation is introduced, and adaptive estimation of multiple unknown frequencies has been studied. The proposed adaptive method has been applied to an actual HDD drive, and the experimental results confirm its effectiveness.