Fluid dynamic bearing systems produced by specified methods are provided.
In one example, a method for designing a fluid dynamic bearing system
includes determining a first stability ratio for a first journal bearing
configuration. The method further includes determining a second stability
ratio for a second journal bearing configuration. In a further example
system, the first configuration has two sub-journal bearings and the
second configuration has three sub-journal bearings. The method may
comprise comparing the two stability ratios to determine whether adding a
sub-journal increases the stability ratio of the bearing system.