Simple question ... How?
If you have one robot, and one light curtain, and one gate, and one E-stop button, all the logic pretty much fits on a couple of rungs that will all fit on the screen of your laptop, and it's simple. But that's not what I'm talking about.
Now try a cell with 15 robots...
I hurt a motorcycle engine yesterday :-/
The engine is a fuel-injected Honda 125cc SOHC liquid cooled single that has a rolling-element bottom end. After about 10 minutes of highway running at approx 10,000 rpm (redline is 11,000 rpm) it lost a bit of power momentarily. I think "that's odd" but...