Click Below to Go Directly to the Content You Need.
I'm New At ThisI Know New WayI'm An Expert

Technology Comparisons


Because of their non-contact nature, porous media air bearings provide advantages that traditional rolling element bearings, or even conventional orifice air bearings, inherently cannot. Here you'll find the performance of porous media air bearings compared to that of conventional rolling element bearings across eight critical characteristics.



Unlike conventional rolling element bearings, porous media air bearings offer a non-contact solution, almost entirely eliminating stiction, thereby providing almost infinite resolution and repeatability.


Rolling element bearings, over time, show wear from mechanical contact, resulting in inconsistent machine characteristics. With porous media air bearings there is no contact, so there is no wear, just consistent performance.

Smooth and Silent Motion

The changing directions of the balls within the raceway of a conventional rolling element bearing results in velocity ripples, which compromise stability and impact performance. Without contact or competing forces, porous media air bearings provide smooth, silent motion.



An order of magnitude separates the speed capabilities of conventional rolling element bearings (3-5 m/s) from their porous media air bearing counterparts (30-50 m/s), which feature no contact and no internal moving parts.


The rotating inertia of the balls in conventional rolling element bearings limits the acceleration capabilities of that solution, in contrast to the non-contact, high-acceleration solution that porous media air bearings provide.


Porous media air bearings ride on a cushion of air, so unlike conventional rolling element bearings there is no need for lubricant, and no resulting lubricant migration or out-gassing, significantly reducing maintenance.

Unwanted Motion

With rolling element bearings, the balls create unwanted motion in all directions (for which no controller can completely compensate). With porous media air bearings, there is no contact or internal moving parts, so there is no unwanted motion or need for such control.


Where positioning is critical, it is important to understand that guideways often exhibit flatness deviations. The momentum of the balls in a conventional rolling element bearing often amplify these deviations, while porous media air bearings average them, keeping linear motion true.