Touch Sensing in RG works thru collisions.
First you enable collisions on robot to trigger robot input and then in MENU -> Setup -> Touch IO you set this RI as Touch sensing trigger.
You also need to enable collisions on positioner, workpiece, ...
Excuse me, I've been busy for three days and it's prompted that I can't find the parts and crashed. Can you take a screenshot to illustrate how to set it up? thank you very much