Gantry skew

One leg runs slightly slower. Close a position loop on the skew and find a gain that holds it without ringing.

Try it: gantry skew control

Leg 2 slower by0.5 %

A worn wheel or a slightly different gearbox is enough.

Skew-loop gain k0.0 1/s

The skew exceeds the flange clearance: the wheels bind on the rails.

Δv = k_skew (x₁ − x₂) ; e_ss = v · δ / k