Re: Going for 3 robots on Ramp?
 

Our regional event judge said yes, a downward protrusion to lift a robot's wheel off the ground would be in violation of the no articulated bumper rules. The rule applies to movement of the bumper in relation to the ground, not (just) in relation to the frame or wheels. It also does not matter if the bumpers stay in the bumper zone, it is the movement of the bumpers that violates the rule.

I submitted a q&a question to verify, but no one else in the room, most with more experience then me, questioned his interpretation.

Now, if your wheel stays in contact with the arena, carpet or barrier or bridge surface, then you're ok but then that isn't what a downward protrusion would be doing.

Re: Going for 3 robots on Ramp?
 

There was a Q&A that said it was legal, but the question wasn't in relation to the "change" in bumper height... So asking it in terms of changing the bumper height is a good idea...

I personally don't see how it is articulating the bumpers as the bumpers are rigidly attached you aren't moving the bumpers you are moving something else. But I'm not on the GDC so my opinion doesn't really matter... also as long as the bumpers stay in the bumper zone why should it matter....

Re: Going for 3 robots on Ramp?
 

This would be true -- if FRC teams were as good as building robots as everyone assumes. The truth of the matter is that teams do not score many points, and by building a simple robot that you can get working, you can often significantly outperform the mean.

Take for example this distribution of OPR in 2011 from Jim Zondag. OPR uses matrix math to approximate the points a robot is worth in a match. Because of how the math works, the true distribution is probably even more skewed!


In 2011, the mean robot scored about 11.3 points/match, but the median (or 50% robot) scored significantly fewer... somewhere around 5.

I would be willing to bet a widebot that is good at balancing the ramp and does not get penalties is worth more than the 50 percentile shooter. In 2011 a consistent minibot would've put you well above 75% percentile by OPR. I don't have 2010 nationwide OPR distribution, but seeing as a consistent hang would put you above the mean robot score (2 pts vs 1.4), that would also put you well above the 50% percentile scoring robot as well.

Building a good robot is harder than most people think. :o

Re: Going for 3 robots on Ramp?
 

I agree with you. But our judge said he wasn't making the call based on this year's rules, but rather on consistent direction from FIRST over the years of what articulated bumper means. He said they could make an exception via a team update, but I haven't seen it yet.

Re: Going for 3 robots on Ramp?
 

The ONLY person you should be listening to in these matters is your Lead Robot Inspector and FIRST HQ.

I don't know what you mean exactly by regional event judge, but if they are not one of the two above people, they may not be a good source of information.

Re: Going for 3 robots on Ramp?
 

Our approach for being the "third bot on the bridge" is to drive up the rail edge with only ~14" of our bot's width (bumper included) above the bridge, and ~19" of our width hanging off the side of the bridge. Most full size bots can still drive past us.

We plan to tilt the center bridge for balls in autonomous, shoot out our preloads, head for our bridge. After autonomous ends, we tilt our bridge for balls and then go over it to play defense. We can shoot balls full court from a spot parked in front of return slot. Near end, we plan to be first bot on bridge and to bring it down for our partners who can, rolling bumper-to-bumper, just drive right past us up to the balance position. They can both stay near center of bridge as we hang off side and near center enough to balance it with them. No ball pickup from floor yet, and this seems like an essential for us to really do well.

-Dick Ledford