The illustration shows one of the common shape errors that occurs with Servo Following Error. In this case, we are showing the error during servo direction reversal in the Y axis. This Flat Error is directly related to two characteristics: Servo Following Error and Mechanical Backlash. While Mechanical Backlash can be improved mechanically or by software compensation, the problem of Servo Following Error dynamically changes according to feed rates.
The Flat occurs when the Y-axis reverses direction. This is because when moving Y positive, the Following Error is a negative error, and when reversing to moving Y negative, the Following Error becomes positive.
The transition from negative to positive (Following Error) creates a servo dead-zone. The size of this dead-zone is directly proportionate to speed and is very difficult, if not impossible, to accurately correct with software, especially as feed rates increase.
With the typical machine today, the only solution operators have is to slow the feed rates to reduce the Following Error, which directly increases the part cycle time.