Sorry didnt get back to this thread until now
Yes it is the C channel from the Kit bot, but nearly all the bracing is custom bracketry. We wanted a smaller channel for the wheels than the little joint pieces allowed, so we came up with our own. We also decided that we wanted the wheels as close together as we could get them without compromising our CG.
We are using the 12:1 banebots transmissions and encoders as we have had a lot of success with them in the past, and the programmers like and know how to use the encoders. We also could not get the long shaft transmissions in time, so we actually went with the Regular shaft, and our mechanical engineers helped with the calculation and design to build a bearing block into the C Channel that supports enough of the weight that we dont need to support on the other side of the wheel (trust me, I didnt believe that you could canteliever it and be successful, but we drove it around all weekend fully weighted and its working beautifully). I think part of it has to do that there isnt a lot of torque on these transmissions, and they explained a whole bunch of other math that I forget now
Even with the 4 motors, we were able to get this thing down to 41lbs including the bumper mounts, and that was a big step for us!! (Last year it was close to 60).
As for bumpers, I dont think I have a drawing, but the back corners we are allowing the pool noodles from the back brace to extend 3.5", and I think the ones from the side brace extend out 2.14". This was the best that we could come up with with the rules, and after 5 of us talked about it for nearly 2 hours, I believe this is a completely legal configuration.
I will post a photo/image if I can soon.