Evaluating distribution of peak signals representing reference track crossings to compensate for thermal expansion when writing spiral tracks to a disk

摘要

A method of writing a spiral track on a disk of a disk drive is disclosed. A plurality of reference tracks are written on the disk. A head is moved over the reference tracks to generate a read signal comprising a plurality of peak signals, wherein each peak signal corresponds to a reference track crossing. At least one of a starting radial location and a velocity profile is adjusted in response to a distribution of the peak signals, and the spiral track is written on the disk using the starting radial location and the velocity profile. In one embodiment, the distribution of the peak signals represents a uniform and a non-uniform expansion of a mechanical component.