We have a robot with a tool attached to the wrist3. There are some cables involved so we had a safety setting restricting the roation of the tool at -180 and + 180 degrees.
This setting has worked for a very long time.
Yesterday we changed the safety settings to unlimited rotation. We rotated the robot wrist whilst in freedrive mode, to figure out what are cable slack is actually, and reverted back the limits to +/- 180 … to our surprise it is as if the encoder for what the angle of the wrist has completely changed , so where 0 degrees used to be… it no longer is.
When we applied the +/- 180 degrees again we were told that the robot is out of bounds ( which it physically was never rotated out of the bounds, as we would have yanked on cabling ).
Is this normal ? Is the wrist3 angle somewhat resettable ? Can someone weigh in on this?
Hi,
Take a look at reset_revolution_counter() myUR
It should help 
Thanks for the suggestion.
I have attempted to use that function but I did not get far.
I am not certain how this revolution counter works, does it count full revolutions of a wrist ?
I have executed the function without parameters, and I also feed it a blank Qnear vector as well as a Qnear of a location that I use as part of my motions.
What seems to have happened is the +/- 180 degrees band we had configured did not translate again into the same band. And I manually typed in a positive angle of 180 and 540 in the safety settings of the installation file … and the robot works.
Thank for the suggestion but I wasn’t able to make sense of the documentation and I am not sure executing that function changed anything for me.
Well unfortuantely I’m still kind of Hosed.
My previous robot program that I had for that robot uses poses, that no longer function correctly after the safety settings changes.
I have used the reset_revolution_counter() , reset_revolution_counter(qNear=[0.0, 0.0, 0.0, 0.0, 0.0, 0.0]). But that doesn’t seem to have an effect.
Any other suggestions would be wellcome, I would hate to have to re-do the program … I would like to reset my robot to it’s previous state but I don’t seem to be able to.
Thanks,
Maciej
Ok,
I think I finally got it.
I set the safety to unlimited rotation.
When the angle of the robot 3 wrist was positive like 9 degrees, I rotated it below 0.
So when it was like 340 degrees.
I did use the reset_revolution_counter().
I restarted the robot controller.
Reset the safety to +/- 180 degrees
And it finally worked.
I feel like the way that funciton is documented in’t great, but thank you very much for brining this to my attention as I’m back in business.