What is a legal bumper?

[lemon1324]

Our team has mounted the axles above the kitbot chassis, and the rail is now 2.5" off of the ground. As the bumper zone starts here, we cannot bolt the bumpers directly to the rail. We were thinking of joining the bumpers to each other at each corner to get a rectangular box of joined bumpers. Where exactly is the plywood backing permitted to go in this scenario? (Alternatively, a clarification on the interpretation of "corner" from rule <R08> would help)

Thanks

[EricH]

Try this Q&A.

[lemon1324]

Ah ok--that permits joinery between segments. Our team is more interested in where exactly the join may extend. In short, is it okay for the join to be in "Zone 2" in the attached sketch?

Thanks

[EricH]

Originally Posted by lemon1324

Ah ok--that permits joinery between segments. Our team is more interested in where exactly the join may extend. In short, is it okay for the join to be in "Zone 2" in the attached sketch?

Thanks

That is what is unclear. From the sound of the Q&A answer, yes, if you protect it with a pool noodle.
However, <R08> makes me a liar. See Figure 8-2 and <R08> bullet 11, which reads "Hard bumper parts MUST NOT extend into the corners."

Translation, you may not be in that zone.

[lemon1324]

Ok thanks

[Al Skierkiewicz]

Arul,
The "corner" in R08 refers to hard edges that can come in contact with other robots. The basis of using the Standard Bumper is so that you and other robots are protected when coming in contact with each other. Contact should only take place in the "bumper zone", bumper to bumper. Use of the kitbot chassis does not prevent you from mounting a standard bumper. The use of aluminum structural angles bolted to the top of the chassis is acceptable. Please remember that the structural material that is used for mounting the Standard bumper, is weighed and sized with the robot, not with the bumpers.

[Jimmy Nichols]

Yes, just mount some Aluminum angle to the top of the rail and mount the bumpers to that.

[countryboy_9115]

Are you sure that we can attatch the bumpers with angle iron? We did not know if you could do that or if you had to attatch the bumpers the way the diagram in the rules shows.

[GaryVoshol]

Originally Posted by Jimmy Nichols

Yes, just mount some Aluminum angle to the top of the rail and mount the bumpers to that.

Originally Posted by countryboy_9115

Are you sure that we can attatch the bumpers with angle iron? We did not know if you could do that or if you had to attatch the bumpers the way the diagram in the rules shows.

The bumper has bolts of some kind going through it. Those parts, and only those, are exempt from the size and weight limits of the robot.

The robot has pieces of angle attached to the frame, with holes for the bumper bolts to be fastened through. Those parts are included in the size and weight limits.

All very legal.

[Scott Carpman]

When in doubt, pool noodles.

[GaryVoshol]

Originally Posted by lemon1324

Ah ok--that permits joinery between segments. Our team is more interested in where exactly the join may extend. In short, is it okay for the join to be in "Zone 2" in the attached sketch?

Thanks

Originally Posted by EricH

That is what is unclear. From the sound of the Q&A answer, yes, if you protect it with a pool noodle.
However, <R08> makes me a liar. See Figure 8-2 and <R08> bullet 11, which reads "Hard bumper parts MUST NOT extend into the corners."

Translation, you may not be in that zone.

I concur with Eric. I wondered how the "joinery" referenced in the Q&A would jibe with <R08>.

Note: Joinery is a woodworking term for connecting two pieces of wood to each other, via methods such as dovetails or biscuits. It does not refer to connecting pieces together with brackets, hinges, etc.

Edit: Since bumpers are required this year, I would make sure that any specific designs that might be questioned by an inspector get pre-approved via the Q&A. You can't just take off non-conforming bumpers this year!