Hello everybody!
I need to set digital outputs after a certain movement (defined with the attribute fine) has been performed, so that the PLC can read them. In practice it happens that sometimes the PLC is able to read the transition, some other times no.
Anybody has any idea?
Is it possible to set the signal to a value for a certain period of time?
Thank you very much! 
PulseDO is the instruction that you are wanting. However, I, and some others like to refrain from using that instruction. I can be problematic. If this step in your process is that critical, I suggest that you use a handshake. Turn on your output until the PLC acknowledges receiving it, then turn it off and continue.
Also check out TriggIO.
Oh, or also setting up a world zone. Just make sure that you don’t pass back through it at the wrong time in your process. WzHomeJointDef would be more safe.