Our floor collector this year was a great success. I was in charge of designing and prototyping the collector mechanism, which our bot solely relied on. After much prototyping, we made the decision at the beginning of week 2 that we would only collect discs from the floor. While this was a risky decision, it allowed us to cut down significantly on the complexity of our design. Instead of using a hopper, discs were stored in a linear path to the shooter. Our 2013 bot was one of the simplest and most competitive in our history.
Our design consisted of a bottom scoop that dragged on the ground, and an articulating intake roller that compensated for the change in angle as discs were collected. The collector was only slightly larger than the width of a disc, but we believed that by adding a camera facing the collector, we could still ground load from across the field effectively during a match. The system worked extremely well throughout competition, and functioned properly for each of our 44 official matches. It's robustness and reliability helped us win two Motorola Quality awards this season, and go undefeated at the Connecticut regional. We were able to use the collector to run feeder station cycles as well. We realized that loading from the floor of the feeder station was actually a lot faster than most human loaded teams. Another cool feature that we discovered was our ability to flip upside down discs. By running the intake roller in reverse, and driving into a disc, we were could reliably flip discs, although we never used this on the field.
We did however, encounter a few problems. At first, we tried using poly-cord to drive the discs. This produced very mediocre results. We experimented with using VEX wheels on the discs, driven by poly-cord, which produced much better results. In the end, we went with Banebots 2 7/8" soft compound hex wheels. These produced an incredible amount of friction on the discs, and worked phenomenally well on the robot. Another challenge was placing the roller wheels in the right locations so that it would maintain contact with the disc as it traveled up the scoop. This was done with prototyping, and we transferred the measurements to our production collector. Finally, maintenance became a big concern. On our practice bot, our collector assembly wore down several times, affecting it's performance tremendously. The wheels, while great on the field, lasted for one competition at maximum.
Match Video:
http://www.youtube.com/watch?v=KsQPrFUpKmk
We only fired 3/4 in auto, so there was still one in it when we went for the center line in teleop. Since our bot is capable of carrying a maximum 4 discs, it appears as though the last one wouldn't collect, since it was full.
This is our bot before WPI. We extended the outer shaft and added extra wheels for Connecticut.
