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Singularity avoidance

#1
Hello,
I'm working on a simulation with calculated positions. 
Depending of the calculation, some targets are close of a singularity. Movements need to be linear, but precision is not important.
Doosan, the brand that I'm using as an option between Auto Avoidance, Path First, Variable Velocity for my program.
So I'm looking for something similar to auto avoidance in RoboDK. At the moment, I'm not able to perform offline programming before I'm getting a singularity error.
#2
I'm not familiar with how this Doosan feature works.
Physically speaking, if you are going through a singularity, you CAN NOT perform a Linear motion.
If you go close to one, the robot will drastically slow down.

Doosan might do some trickery to avoid the singularity, but it's certainly not running a linear motion through it. It's just impossible.
It might be changing the path without you noticing, or even having a way to notice it.

With RoboDK, if you are using the Curve Follow Project, you can use the optimization parameters to rotate around the tool z to avoid singularities.
Or you can use the API to do a MoveL_Test and see if it results in a singularity or not and adapt your path if it does.

Jeremy
Find useful information about RoboDK and its features by visiting our Online Documentation and by watching tutorials on our Youtube Channel


#3
Hi Jeremy,
That's exactly what the Doosan option is making (it also exists on Fanuc, Abb and many other brands). The linear path is changing a little, so my program is not affected and continue running even if it's close to a singularity. That's the kind of option that I'm looking for.
#4
We can't do this exactly in RoboDK.
What you can do is reduce the singularity threshold detection in "Tools"->"Options"->"Motions" (-1 will deactivate it completely). It should be +/-2.5 deg by default and activate the avoidance on the robot when you run the real program.
Would that work?

Jeremy
Find useful information about RoboDK and its features by visiting our Online Documentation and by watching tutorials on our Youtube Channel


#5
Hi Jeremy,
Disabling singularity with -1 seems to work in my simulation.
Thanks for your help!
  




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