Backlash Compensation

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(Redirected from Gearplay Compensation)

CPRog can help to compensate backlash(=gear play) in software. This might increase precision in some applications, in others it might not.


  • CPRog Version V902-10-016 from March 2018 or later


Roboter Ini file with GearPlay Compensation

The backlash compensation can be configured in the robot ini file at c:\CPRog\Data\Robots\yourrobotinifile.xml

Please use "." as decimal separator!

For each joint the tags "GearPlay" and "GearPlayInc" can be adapted:

  • GearPlay: Enter the mechanical backlash in degree in this joint. Values from 0.0 to 3.0. Needs to be higher than 0.1 to activate the compensation.
  • GearPlayInc: Enter the velocity in degrees per cycle of backlash compensation. Values from 0.0 to 0.5. Should be around 0.05.


To test the compensation:

  • Make the changes in the ini file, save the file and start CPRog. Changes take effect only after a new start of CPRog.
  • Set the override to e.g. 3%. Now move joint 1 a little to the left and to the right. Results:
    • If it does not move, the "GearPlay" Parameter should be increased.
    • If it moves too much, then the "GearPlay" parameter is too high. The backlash is overcompensated.
    • It should move just a little, then it is ok.

Side Effects

  • When moving the robot for the first time, there might be a small motion when the backlash compensation is initially applied.
  • Please test the compensation in combination with your referencing procedure. Verify the referencing precision from different starting positions.