Bumper rules


#1

For bumpers, is there a limit on how far into the frame perimeter part of a bumper can extend? I’ve looked through the rules, and can’t seem to find one, but would like to double check with other people. ex: if we added a bracket to the corners of our bumpers, that has a triangular support to strengthen the corner, is that legal? Thx.


#2

Nobody’s found one that I’m aware of… Just watch the 15 lb limit.


#3

R31.F. optionally use metal brackets (i.e. angle or sheet metal) to attach BUMPER segments to each other.

The question becomes “is a triangulated angle bracket covered off under “angle” bracket”. When in doubt, ask the Q&A for a ruling.

However, if the metal parts are in contact with the frame, then I would think that they become part of your bumper mounting/support system and there are no restrictions there, other than the weight limit.


#4

There is not specific rule about bumper parts extending INTO the frame perimeter. But the GDC tends to interpret the bumper profile sketches in the manual pretty literally. Using that as a basis, the only thing allowed into the frame perimeter are the robust bumper attachments. Which can have the side effect of stiffening the frame and bumper. So make sure your corner bracket is attaching the robot to the bumper and you should be good. Just a brace extending into the frame perimeter would not be legal in my opinion.


#5

This topic was brought up a few months ago: Bumper Frames - Are They Legal?

If I recall, the consensus (but not an official ruling) was that angle brackets across the corners SHOULD BE legal.


#6

Zero. By definition is it only a BUMPER if it is ON the FRAME PERIMETER. Things inside the frame perimeter are not bumpers.

That being said, I think your rackets will be fine,


#7

This is how I interpret it also - if a mounting part is attached to the bumper, it’s part of the bumper and subject to bumper zone rules, and if it’s attached to the frame, it’s part of the robot and subject to frame perimeter rules. The bumper zone doesn’t have any rules for inward-facing parts, so as I read it, any brackets that extend over or into the frame perimeter are okay. The limitation to going overboard with brackets, as @EricH and @bjtheone mention, is the bumper weight limit.


#8

The issue is what @Frankj raised. RIs want your BUMPERS to conform to the pictures. If they were an attachment point then they would definitely be part of the rigid fastening system, which is fairly wide open.

R31G covers off attachment and figure 10-6 shows the cross section. Neither of those specifically calls out bracing that extends over the FRAME as legal, since bracing is not attachment. R31F shows pictures of legal brackets and specifically calls out (angle or sheet metal) and does not show them as extending over the FRAME.

I would pitch the “its not specifically ruled as illegal, so its legal” defense, but I would also shop for a Q&A answer to back me up, if they were my BUMPERS. Remaking bumpers at events sucks.