When your application requires precision positioning, it is important to understand that rails and guideways often exhibit flatness deviations. Some of these are inherent…others may develop over time. Either way, the momentum of the balls in a rolling element bearing actually amplify the unwanted motion of the bearing. In fact, rail-ball contact further damages both the rail and the balls. This is a frequent scenario with conventional bearings and systems.
When using porous media air bearings, exactly the opposite is true. Because the bearing rides on a cushio of air, there is no contact. Instead, the air bearing actually averages any irregularities in the rail. Without contact, there is no damage to the rail, let alone increasing damage.
The porous media air bearing solution keeps the smooth, frictionless motion as close as possible to theoretical perfection.