KR6-16 Arc A3 limit seems to be wrong

[Xylotica]

I recently ran a program on my KR6-arc, and although there was no warning in the simulation, during the execution, I hit a "A3 angle software limit".
It was easy to fix since I just had to offset my work a little and generate a new program, but I though that this should not happen.
I also looked for a way to visualize the settings from pre-defined robots, but , apart from using the simulation graph, I couldn't see how to do this.

Cheers,

[Johannes @ Robots in Architecture]

Hello,

There can be a few reasons for that, first of all of course that there is an issue with the simulation - however I just checked the code and it seems to be identical to your screenshot.
You can also set software limits for each axis, so it is entirely possible that e.g. someone before you restricted the robot for a particular task. If you see that, be careful about changing it back the the default position as that person may have added mechanical stops as well.
Also, KUKA|prc only calculates the programmed positions. If you also want to see the positions between that, you would have to enable the LIN interpolation in the settings. Finally, if the tool and base values of the simulation and reality do not match up, you won't get a reliable simulation.

Best,
Johannes

[Xylotica]

Hi Johannes,

The robot's Base is consistent with the simulation's base since I use the robot's default base, identical to it's "world" coordinate system.
The point at which the problem happened is really at the "edge" of the simulation, so I doubt that it would have an intermediate position going further out.
Where should I look for these software limits to check if they are the same as the nominal values ?

Also : Is there a way to visualize easily a preset robot's parameters ?

Cheers,

[Johannes @ Robots in Architecture]

Hello,

If you've got a particular position that causes the problem it makes trouble-shooting much easier.
Just send me a Grasshopper file with just that single position (which shows up as valid in PRC, but doesn't work with your robot) as well as your exact tool and base values and I can double-check with KUKA SimPro if there is any difference between KUKA|prc and the official KUKA software.

Best,
Johannes

[Xylotica]

Hi Johannes,

I checked all  the software limits ; strangely, everything is set to "0"...

Cheers,

[Johannes @ Robots in Architecture]

Hmm.. That is really strange... Is that where you checked the axis limits? (see attachment)

[Xylotica]

Yes, exactly,
All the values are set to zero

[Johannes @ Robots in Architecture]

Hello,

Hmmm... As I wrote in the eMail, your robot seems to have a problem at 145.1 degree for A3, while A3 should actually go up to 154 degree, as per the manual.
Before I didn't read my own screenshot properly, because it says that setting it to 0 means that the checking is disabled. My guess is that someone edited that and accidentally switched numbers, going for 145 instead of 154.
Can you send me the $machine.dat file from the R1/MADA directory? Maybe rename it to machine.txt so that your eMail client doesn't complain about strange file endings.

Best,
Johannes