Track-seeking control using input-shaping method to reduce vibration in HDD

Abstract

Hard disk drives are used for storage information in its recording disk or media. Actuator arm is mechanical part to move heads that fly over a track from any position to the target track. Accuracy signal and access time are the key parameters to control the actuator seeking position. However, the accuracy signal and access time are adverse when actuator moves faster and then the system create the residual vibration at the target track. The causes of the vibration are part from the fact that the reference signals, which are acceleration, velocity, and position, have high power spectrum energy over wide frequency range including over the actuator's natural frequency. The input shaping is convolved two signals at referent position signal and properly designed impulse signal. The impulse sequence produces an input signal to cancel residual vibration, then the result is smoother and the residual vibration is canceled in actuator-arm movement. Hence the residual vibration should be reduced by the recommended input shaping.