Are these bumper configurations legal?


No. Read the manual because the following is in there in official talk. If I say something wrong or what I say is misinterpreted, you might suffer because you didn’t read the manual.

BUMPERS must be around the full FRAME PERIMETER and be attached to a solid piece of frame.

Not in my interpretations.

The first clearly does not have 100% coverage.

The second does not fully cover the BUMPER PERIMETER. That is defined as a string encircling the robot at BUMPER ZONE height. The string would not take the path through the cutout as shown.

what about “b”?

Keep in mind that the bumpers will be 10" off the ground, so the balls will not make contact with the bumpers. In image B, the ball would go past that inner bumper and be more than 3" inside the frame perimeter. Image A could work if you have solid frame above that cutout to attach a bumper to.

You are not attaching to the frame perimeter as required by <R07>. Therefore, illegal.

If you would like to know about bumper rules, read Section 8 of the Manual, specifically <R07>, <R12>, and the definitions of Frame Perimeter, Bumper Perimeter, and Bumper Zone in Section 8.2.

I have been out for a while so the bumper rules are a bit new to me.

Is it correct to say that the you imagine that you project the robot top view down to a sheet of 3/4 ply would, cut out that profile and then strung a rubberband around the cutout (along the 3/4" side), then the path of the rubberband would be the path that the bumper would have to take?

Perhaps that is more confusing that it should be but perhaps not.

Joe J.

Confusing, yes. But it gets you point across. :smiley:

That is indeed correct. :smiley:


The bumpers are mandated by the GDC these days to provide max protection for the robot. Neither design shown above would be legal this year…

<R07> Teams are required to use BUMPERS on their ROBOTS. BUMPERS have several advantages, such as reducing damage to ROBOTS when they contact other ROBOTS or ARENA elements, and being excluded from the calculation of ROBOT weight and volume constraints specified in Rule <R10>. The BUMPER location and design have been specified so that ROBOTS will make BUMPER-to-BUMPER contact during most collisions. If implemented as intended, a ROBOT that is pushed against a vertical wall in any normal NORMAL CONFIGURATION will always have the BUMPER be the first thing to contact the wall. To achieve this, BUMPERS must be constructed as described below and illustrated in Figure 8 – 1.
A.** BUMPERS must provide complete protection of the entire FRAME PERIMETER of the ROBOT (i.e. BUMPERS must wrap entirely around the ROBOT).** The BUMPERS must be located entirely within the BUMPER ZONE when the ROBOT is standing normally on a flat floor, and must remain there (i.e. the BUMPERS must not be articulated or designed to move outside of the BUMPER ZONE).
From definitions…
FRAME PERIMETER – the polygon defined by the outer-most set of exterior vertices on the ROBOT (without the BUMPERS attached) that are within the BUMPER ZONE. To determine the FRAME PERIMETER, wrap a piece of string around the ROBOT at the level of the BUMPER ZONE - the string describes this polygon.

Emphasis is mine. Teams also need to remember that the bumper zone is between 10 and 16 inches above the floor while the ball is less than 9.5 inches in diameter. You are in POSSESSION of the ball while it is contact with the floor but you CARRYING the ball if you possess it without it touching the floor.