Reverse the motion direction

Reverse and weight the friction curve

In the Stribeck curve model, a jump in feedforward control current occurs in the axis reversal process (velocity zero crossing).

To prevent this discontinuity, the CNC monitors axis reversal. In this case, the friction model may be weighted before and after zero crossing.

• Before zero crossing:          time [number of CNC cycles]
• After zero crossing:       Path distance covered [0.1 µm]

Notice

If no reversal takes place, i.e. the axis is only decelerated and continues in the same direction, the friction model is not weighted.