1/2" bump in field?

Has anyone figured out why the bump in the field is stated as being 1/2"? We built our chassis and have got the clearance to be about 5/8" which is cutting it close to this bump. However the more we investigate the cause of the bump, it seems it shouldn’t be that much. In the field specs there is the support plate for the lane divider which is 3/16" thick, protrudes 2 feet into the lanes, and I assume it is placed underneath the carpet. When we place a 1/4" plate under our carpet the bump is very slight and nowhere near 1/2". Anyone else with a low rider bot chassis thinking about this too?

It’s on top of the carpet, covered by carpet. You’re right, it might not be that much. Still, it will affect gameplay.

Oh wow I hope this isn’t true. Our robot IS 1/2" off the ground!!!

Where is this written, how did I miss it?

-q

Section 6.2.3 of The Manual, in the section describing the Lane Divider:

The LANE DIVIDER is attached to vertical posts that are anchored to supporting plates covered by carpet. Note that these plates will create a bump in the carpet approximately 1/2 inch tall, and as a result the surface of the TRACK will not be perfectly flat.

EricH is correct, the bumps are caused by the supporting plates being placed on top of the baseline carpet, and then covered with additional pieces of carpet that are then taped down to the field carpet. So the 1/2 estimate is a reasonable one (and then when you throw in the general statement at the beginning of Section 6: “the arenas are assembled in different venues by different event staff, small some variations do occur. Fit and tolerance on large assemblies are ensured only to within 1/4 inch. Successful teams will design robots that are insensitive to these small variations.” things could start to get very interesting if you are only designing a robot with 1/2 inch ground clearance).

-dave

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I’ve seen some team pictures with 3/8" clearance. If one team is doing, there must be others. I’m worried about some of these teams that aren’t reading the rules that closely.

See also this thread with Kickoff pictures by Elgin Clock. And it is multiple bumps, not just a single one.

I was at kickoff at manchester and the bump there was ~1/2". However it is located in an area on the field where it would be impossible to “straddle” it. Meaning you wont be able to get your right side/left side wheels on opposite sides of it. This means that you will get a set of wheels over it which should make it a non issue.

For our team, we didn’t catch this tell we went up to another teams shop to use their mills and one of their mentors pointed it out us. Luckily I didn’t know how easy it was for the build team to drop the wheels down some, so like the next day it was fixed clearing something like 3/4"(before it was like 1/4").

Also, don’t forget. It’s not just your chassis that needs to be able to clear this, it’s also your manipulator. It’ll be interesting to see if some of those fork lift devices get hung up on the support plates.