Bumper notch, R21

[RandeJ]

We have a design where an appendage comes down over the ball to retrieve it. The attachment points (2) are just above our drive frame. When we put the bumper on, we noticed that it interferes with the motion of the appendage ever so slightly. We are considering putting a small (1/2" deep by 1" wide) bevel at the top of the bumper plywood to prevent this.

We're going to ask Q&A for clarification, but we were wondering if anyone else had run into something like this. It's not really clear if this impacts bumper integrity, is a small clearance, etc.

Our alternative is to raise the hinge point a 1/2" to clear the bumper. But that's a fair bit of work we'd like to avoid if possible.

[mott]

My understanding of the various bumper rules and Q&A responses would lead me to believe (not official obviously) that notching the rigid bumper backing is NOT allowed. If you can't install 8" of unaltered bumpers on each "corner" of your frame perimeter, you'd likely be illegal.

If your appendage attachment points are within 8" of the corners of your frame, I'd say you're going to need to alter your hinge points to be legal.

[45Auto]

I have NEVER seen a robot that had the edge of it's bumpers modified to clear a mechanism pass inspection.

R21 has traditionally been interpreted to allow minor clearance pockets on the rear face (frame side) of the bumper for bolt heads, E-clips, etc, that protrude less than 1/4" past the frame perimeter.

If I were you, I would modify the robot to use un-modified bumpers NOW while you have time and tools available, rather than have to do it in the pits at the competition.

[cgmv123]

R19 and R21 do not mention notches to allow for robot mechanisms.

[Al Skierkiewicz]

Rande,
The above answers are correct. Sorry.

[RandeJ]

Thanks everyone. Rather deal with it now than at competition. Preponderance of the evidence says it won't fly, so we'll work around it.

[Alan Anderson]

The rules don't accommodate the kind of notch you're suggesting, but they do permit leaving a section of frame completely uncovered. As long as you keep 8 inches on either side of each corner covered by a bumper segment, you can have the center part of a side of the frame open.

[RandeJ]

We thought about that, but we're ~28" square. So after 16" come off, we don't think there's enough room left over to separate the hinges. We're just going to raise them to make it all work. Our mech team was worried they were about to run out of fun things to do anyway...