pic: 2009 Bot from Team 368

[Alan Ing]

Hi Adam,

You were on 294 right? It was a pleasure competing on the same alliance during the finals in 07'. It would have been even better to have won! However, there is no shame in losing to an alliance led by the Beachbots!

I wouldn't say that our bumper system is light or that efficient. We wanted to be able to maximize our turning force so we went with a 6WD with driven axles and shoved the wheels out as far as we could. Of course because of this years bumper rule, we had to fully support the back of the side bumpers leaving no gaps around the wheels. We weren't too thrilled with this new rule as our bumpers in the past have been supported by standoffs without being fully supported and have never once even showed signs of failing. Last year we attended 4 competitions Oregon, Hawaii, Championships and IRI and we all know how hard machines were getting hit that year.

In order to fully meet the requirements of the new rule, we basically added a solid heavy 2" x 1/4" x 27-3/4" Aluminum plate down each side of the machine supported by substantial standoffs at the corners and around each wheel. Fortunately for us, pneumatics or a two speed auto shifting gearbox wasn't necessary so we had the extra weight allowance (just barely robot weighs 119.7 lbs according to the scale at the Hawaii Regional). I have a picture I can post later if you would like to see it.

I don't think anyone would doubt that it would be considered a real frame member. We did not want to take any risk and wanted to make sure it passed inspection. It is substantial and unfortunately heavy and after reading the GDC's responses to peoples questions, we felt confident it would pass. The bad thing is that it also makes wheel and chain adjustments a pain as we now have to dissassemble it to do any sort of maintenance or adjustments to the wheels which takes away the advantages of using a shaft driven system. The bumpers themselves come off fairly easy we use a 1/4" pin that locks the bumper around the side frame plates. They come off in a few seconds.

Although I understand the intent of the bumper rule, I do think that perhaps this rule is a bit excessive and would suggest that it be revisited in the future as a properly supported bumper is possible (and not that hard to construct) without resorting to this.

Alan
Mentor Team 368