[Aleix Ripoll]

Hello RoboDK team,

Now, we are working with a real ABB robot (IRB1660ID-4/1.55) and we have realized that there is a not negligible difference between the virtual robot model and the real robot. We had the robot base frame displaced 5mm in Z direction. So, we have already modified manually  our robot kinematic parameters in the roboDK station to match with the real robot. Now, the virtual robot differs from the the real robot about 0.044mm in X, 0.001mm in Y and 0.002mm in Z. We know that roboDK has an option to get better accuracy by different calibration procedures (laser tracker for instance) but this is not the topic to discuss now. 

We would like to ask you if it is normal to find errors more than 1mm in the baseframes of the robot, other joints definitions or robot flange. If so, we would always be interested in calibrating the robot kinematic parameters.


Thanks you,
Aleix R.

[Jeremy]

Hi Aleix,

@Olivier is on the case.
He will keep you posted.

Jeremy

[Olivier]

Hi Alex,

Try this version and let us know if the parameters fit the real robot better.

Olivier

[Aleix Ripoll]

Dear Olivier,

Thank you for providing us a new modified 3d model. This model also fits with the real robot. 

I have attached a picture showing what we did in our initial 3D abb model. We have just modified manually the base frame of the 3D robot model to adjust it to our real robot. Then, we are calibrating manually the virtual robot to the real robot and get more accuracy in our OLP programs. Am I right?

Our question is about how often we will find differences between the theoretical 3D models from your library and the real robots. If you say that it is usually to find differences, we will consider to always make a calibration as you explain here:

https://robodk.com/doc/en/Robot-Calibrat...acker.html

Thank you for your time,

Aleix R.

[Jeremy]

This should not occur very often.
We find discrepancies a few times a year throughout our +600.

Jeremy