Variations of the Bumps?

[Creator Mat]

My team is wondering do we know the expected tolerances with the height and angle of the bumps? I remember reading about some variance but couldn't figure out if they where exceptions or the rule

[JamesByrne]

in the field drawings it says the tollerances the field is built to.

The size of the components is +- 1/32 nd of an inch

and the angles are +- .25 degree

I think those numbers are right, I am trying to remember them off the top of my head.

[Tristan Lall]

Originally Posted by JamesByrne

in the field drawings it says the tollerances the field is built to.

The size of the components is +- 1/32 nd of an inch

and the angles are +- .25 degree

Don't rely upon those tolerances!

Although FIRST surely put a lot of effort into preparing the field plans, those are wholly inappropriate tolerances for many of the dimensions given. They're not impossible, they're just impractical and unlikely to have been followed, especially for assemblies. (FIRST has never been very good at providing sensible tolerances for the dimensions in the game manual and drawings.)

Consider instead the advice of 6.1.1: "Fit and tolerance on large assemblies (e.g. the TOWER) are ensured only to within ¼ inch. Overall gross dimensions of the entire field may vary up to 4 inches. Successful teams will design ROBOTS that are insensitive to these variations."

[gburlison]

When you consider that the rules state that the bump is 12" tall, but the field drawing puts it at more than 13", whats a few extra 1/32 of an inch here or there.

[Dad1279]

There were large differences in overdrive field 2 years ago. In some cases the overpass was inches lower in the center, and the field grew longer during the competition as robots rammed the drivers stations.

It would be prudent to build adjustments into your design