Modal analysis of two-dimensional translation stage

dendavis

What is the best way to model a two-dimensional stage supported by bearing blocks on guide rails for the purpose of identifying resonances? The two-dimensional stage is oriented vertically so the vertical axis is parallel to the gravity vector and the other axis is horizontal. So the bearings on the horizontal rails are preloaded by the stage weight vertically, whereas the bearings on the vertical rails are not preloaded.

Victor

You can use the modal vibration analysis type with stress stiffening (under Loads & Constraints). You apply whatever loads it has (gravity) and it'll include their effect on the stiffness of the structure.

If the "bottom" (furthest from the stage) rails are effectively rigid, I would think you can use either displacement or frictionless support constraints on their bearings.

For the bearings between the stage and the middle section, you could fix them together since Mecway doesn't have a sliding contact for linear analysis. If that's not appropriate, you can make a fake sliding contact by joining the two parts with high-stiffness truss elements that are oriented normal to the surfaces. That allows free lateral movement between the two surfaces but constrains movement in the normal direction.

dendavis

Thanks Victor. This is informative.