How is your team doing this? Is there any feedback from the feeder/human player to the drivers?
We have a signal light tower that will be mounted on the robot for notifying the feeder of what tubes we want:
This is the "mock-up" of our current idea, which is a couple layers of strip LED lights (which are commonly also used as underglow...typically). If you're wondering about the material, they're CDs with milled holes that fit to PVC piping.
As you can see, it's REALLY BRIGHT!!!
Green - Got a tube (banner sensor on manipulator)
Red - Triangle
White - Circle
Blue - Square
Pretty cool, right? (Obviously they won't all be on at once during teleop, but we're excited about having some serious dance party lights during autonomous!!!)
GP isn't just a good idea, it's mathematically optimal. - Jared Russell [more] 
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