We had a very long, arduous journey over the course of the season to prototype and perfect our intake. Our original intake design was like many others with a single double wide roller in the front and a "scooper" plate underneath. Here's two pictures of our original intake design, the pool noodle on the front was just a bumper to protect the roller underneath. The entire roller was on a hinged arm that allowed the roller to actuate vertically
In this picture the black rollers were made of a low durometer urethane called sorbothane, it was by far the most frisbee-adhesive material we could find. If you just laid the sheet of sorbothane on a frisbee you could pull the frisbee across the carpet with only the weight of the sorbothane holding itself down.
This intake design was fairly successful, it picked up almost every frisbee we touched, however like other teams we occasionally had some jamming problems when feeding 2 discs next to each other and the scooper plate getting stuck on the carpet lip around the pyramid. The other problem was that it would push the frisbees a short distance before picking them up which was a problem in autonomous. We went back to the drawing board using 254's intake as inspiration. Our final intake design worked better than we ever could have dreamed.
Our final design used a thin front roller with a polyurethane sheet wrapped around it that had similar traction properties to the sorbothane. The entire intake was wide enough to pull in two frisbees next to each other. Only having the traction on the center of the front roller allowed us to pull in one frisbee at a time without them fighting each other while being pulled in.
Behind the front roller we had a counter rotating roller with the same polyurethane traction material on it that lifted the edge of the frisbee and pulled it into our hopper. We also had another roller directly above it with a large brush on it, rolling in the same direction as the front roller, to assist the frisbees getting pulled in after the bottom roller had lifted the edge. This intake design worked flawlessly, it instantly picked up any frisbee touching the front roller, never had jamming issues, and had an additional, accidentally built in feature, if you picked up an upside down frisbee then lifted the intake it would flip the frisbee out right side up to be picked up again
Our final intake also had no bottom scooper plate and the entire intake rolled on two steel track balls which kept the front roller at a consistent height and allowed easy transitions over the carpet lip. Our intake also took a much heavier beating than it should have including a full speed hit against the pyramid and several pushing matches with other robots. We did end up bending the side plates that make up most of the intake however we reinforced them with a set of back-up plates that we had brought along in case that happened.
I'm sure most of you saw this live but here's a match with our intake after it had been "Frankensteined" back together.
http://www.youtube.com/watch?v=U_blP_tD8Yk
Thanks to 973 for the great quality video of the einstein matches.