Using the CoBot as a measuring device to measure straightness

Technical Questions
1

I’m currently using our CoBot to measure surface heights. To do so, I lower the Cobot onto the surface until a defined force is reached. I then save the height of the TCP.

At the moment, I am not able to distinguish differences in the region of 0.05 mm by that method.

To clarify, I’m using the force copilot URCap. I give a downward force of 5 N onto the Z axxis, and let the tcp drive a prerecorded path (in which it is standing still, with no force applied). I save the height at the moment it doesn’t change anymore in a seperate thread.

Have I reached the limit of what is possible with the CoBot, or are there other methods to measure objects in a touching manner?

2

0.05 mm (.002 inches) is well past the robot’s capabilities.

I believe 0.10mm is the best you can get and that would be under ideal conditions. If you’re getting 0.05 you’re doing well.

3

E-series robots have a pose repeatability of 0.03mm for the 3e/5e and 0.05mm for the 10e/16e. With that said, any sort of error in the rest of the system will probably take you out of the range that you are looking for.

4

Has this changed in the last 2 years? I’m fairly positive we were told 0.1 when we bought ours.

5

Nope, E-series has always had those numbers. CB3 does have 0.1mm for repeatability though.

6

Oh. I sit corrected (and deceived?) <—Totally not complaining! :stuck_out_tongue_closed_eyes: