A wheel assembly for a vehicle comprises a spindle and a wheel carrier. For example, a user can select one or more regions of one or more disparate web pages for which heshe desires updated information over a length of time. The controller also includes a duty-cycle controller configured to sample the current-sense signal at mid-points of duty cycles of the power switches and regulate the characteristic as a function of the error signal and the current-sense signal. Alternative embodiments include a sync feature for each servo sector formed by a selected groove andor land pattern as a marker for the start of the servo fields.