Abstract: The present invention provides self-servo writing by which self-propagated servo pattern track shape errors are reduced or eliminated. The method includes providing first servo bursts on a first track, measuring edge errors of the first servo bursts, and self-servo writing second servo bursts to a second track using different combinations of the edge errors to adjust the position error signals for the second servo bursts.

Abstract: A sinusoidal acceleration trajectory controller is used in positioning a transducer at high speed to minimize vibration and acoustic noise. The controller reduces vibration and acoustic noise without sacrifice of seeking time by using a sinusoidal waveform as the actuator input. This sinusoidal waveform is a function of target track position and the seeking terminal time. When the velocity of the read/write head on the transducer reaches a maximum velocity, the sinusoidal waveform becomes a segment sinusoidal waveform, including a zero value waveform between two half sinusoidal waveforms. The amplitude of the sinusoidal waveforms and the coast period are minimized to obtain the minimum harmonic content in the segment sinusoidal waveform.