Rule <R09> & <R12> contradictory?


At the time of inspection, the team must declare in which weight/height class (as specified in Rule <R07>) the ROBOT will be configured for the competition. Once inspected for the declared weight/height class, the ROBOT must remain within the weight/height restrictions of that class for the duration of the competition event. Modifications or changes to the configuration of the ROBOT after the start of the competition that change the weight/height class of the ROBOT will not be permitted.


**Once the match has started, the ROBOT may assume a PLAYING CONFIGURATION that exceeds the size dimensions specified in Rule <R07>. **While outside of its HOME ZONE, a ROBOT may expand up to a maximum width of 72 inches and depth of 72 inches. While entirely inside of its own HOME ZONE, there is no limit to the maximum width or depth of the ROBOT, as long as it remains entirely within the HOME ZONE. There are no height limits for a ROBOT in its PLAYING CONFIGURATION at any time after the start of the match (other than those naturally created by the ceiling height of the competition venue).

Can anyone define competition event? Rule R09 says you CANNOT exceed, while R12 says that you have to stay within 72x72 while on the playing field. Looking around the forums, it seems the general view is of the latter, but I just wanted to clear that up. When they say “competition event”, do they not also mean the match?

Perhaps there is something simple I am overlooking because I seem to be the first one asking this question on these forums. Someone else should have noticed this before, right?

The height/weight restrictions are for the starting class.

Competition event refers to the competitions and the matches, but other rules may define parts during which the rules are different.

My understanding of the intent is that they meant to say that robots must remain within the class they declare at their first inspection throughout the event. While in a match, your robot may expand to the allowed footprint of 72 sq. in.

In other words, you can’t pass inspection with a 6’ tall, 100 lbs. robot and then, in the elimination rounds hack off 2’ and add 20 lbs. of balast. That would represent a change of class and is disallowed.

They make perfect sense, <R09> is saying that once you register as a 6 ft tall 100 lb robot, you have to stay a 6ft tall 100 lb robot for the rest of the competition weekend.
<R12> is saying that you can expand out of the starting envelope for your particular weight-class once a match starts.

At least that is how I take it…

it means when you are getting your robot inspected at the beginning of the regional/nats you have to pick a weight/height category and stick with it but while you are in a match your robot can expand. at the beginning of each match you have to be in the size envelope whether it is 28"x38"x4’, 28"x38"x5’ ect.

edit: Cody beat me to it.

They rules don’t contradict. Each class only limits your starting dimensions not the dimensions you may expand to during a match.

There are three possible weight/height robot starting configurations. <R09> says ou have to pick one, and stick with it, throught the whole weekend. For example, if you build a 110 lb 5ft high robot, you can’t add weight to it after inspection, even if you reduce it’s height to 4 feet or less.

The 72" x 72" “virtual box” rule applies to robots after play has begun, your robot can expand to any size that will fit within a 72" wide by 72" long by as high as the ceiling box. But you’ll have to fold it up again before the beginning of the next match.

also it can be any size when it is in the home zone (although the home zone is only 8 feet by 26 feet, so that is the effective size limit there)

Reguarding R12 - I understand that you can’t expand more than 72 inches. Does this maximum also count for the arch swing of a mechanical arm for picking up the tubes?
For example, if our robot is 38 inches and our arm expands say 40 inches outside of our robot, would FIRST not allow this? It would be pretty difficult for a robot to get to the top spider with an arm that is shorter than 34 inches if it didn’t have some kind of elevation mechanism. Can someone clarify?

This question was just answered again on the FIRST Q&A:

“The purpose of Rule <R12> is to define a 72 inch wide x 72 inch deep x infinite height (save as may be practically limited by the venue ceiling height) three-dimensional box. When the ROBOT is not in the HOME ZONE, it must maintain a configuration that will allow it to fit within this virtual box at all times. The virtual box moves with the ROBOT, and the ROBOT may be oriented within the virtual box in any direction. But if any part of the ROBOT, at any height, ever extends outside of the virtual box while the ROBOT is not in the HOME ZONE it will be considered a violation of Rule <R12>. There is no case in which an object measuring greater than 102” horizontally will fit within the 72 x 72 inch limits specified. Any such device will violate the rule if it is used outside the Home Zone."

So, draw a sketch of your robot sitting in a larger square, probably at a 45 degree angle, with the arm stretched out to the opposite corner of the box. Dimension the robot and the box. Does it fit? do the geometry/trigonometry problem…see what happens…it’s just like math homework, except that the answer means something! :slight_smile:

So, what you’re saying is that all that Math is useful for something other than taking tests? Wow, whooda thunk it?


perfect sense

once again we have a case of peolple reading the rules but not reading defenitions ( you know the BIG BOLD WORDS )

Don’t forget about your bumper dimensions while you’re applying ol’ Pythagorus.

Thanx guys. That’s what we thought but we just wanted to be on the safe side. Doesn’t fare too well if we find out on competition day that our perception of the rules is different from that of FIRST.

heh, now that I look back at it, it does seem pretty obvious :rolleyes: