[tim-tim]

Hmmm ok, so that idea doesn't work.

Is it possible to turn the rollers by hand to "roll/grab" the ubertube? There may be a simple way to add a hand crank on the output shaft to turn the rollers that way as well.

Again, these are just ideas, I don't want to see you give up. In 2007 we had to take a pin with us to switch the solenoid on the robot to load the keeper (equivalent to the ubertube) tube. Try and be a bit creative, while staying legal.

Hope this helps