bumpers for interior perimeter

[EricH]

Sunshine, it's not illegal because there's a cutout. It's illegal because a short distance of frame perimeter (which, I remind you, is independent of cutouts) has no bumpers on it, and the rule says

BUMPERS must provide complete protection of the entire FRAME PERIMETER of the ROBOT (i.e. BUMPERS must wrap entirely around the ROBOT).

(emphasis mine)

If it were something like 1/4", you might have a case, as normal bumper joints are nearly that big. But to be big enough to let an arm out, it's almost got to be several inches. Try being the LRI who lets it through because it's protected despite the gap, only to have every other team at the event complain that that team just got a competitive advantage!

Cutouts were permitted a couple years ago because there was not a 100% protection requirement. IIRC, it was something like 75-80%. Starting last year, it went to 100%.

[cbeavers6790]

last year lots of teams had openings in their bumpers to allow for a kicker mechanism, pusher, etc while the cutout will be differnet the idea that the inside of the cutout would not be the first thing to touch a vertical wall in a collision it wouldnt need bumpers if you have anything that would help me make sure i am correct in this idea i would appreciate it

[GaryVoshol]

Originally Posted by cbeavers6790

last year lots of teams had openings in their bumpers to allow for a kicker mechanism, pusher, etc while the cutout will be differnet the idea that the inside of the cutout would not be the first thing to touch a vertical wall in a collision it wouldnt need bumpers if you have anything that would help me make sure i am correct in this idea i would appreciate it

Nobody in Michigan did, at least not among the 80% or more of teams that I saw. BUMPER coverage was required to be 100% last year too. The difference was that the BUMPER ZONE was higher last year, allowing the balls to go below the BUMPERS.

The issue is not the flat-wall test; the issue is the 100% BUMPER coverage requirement from <R07-A>.

[EricH]

Originally Posted by cbeavers6790

last year lots of teams had openings in their bumpers to allow for a kicker mechanism, pusher, etc while the cutout will be differnet the idea that the inside of the cutout would not be the first thing to touch a vertical wall in a collision it wouldnt need bumpers if you have anything that would help me make sure i am correct in this idea i would appreciate it

Last year, the bumpers were higher. There wasn't a single team to my knowledge that had a gap there intentionally (100% coverage again).

The frame perimeter is defined as

BUMPERS must provide complete protection of the entire FRAME PERIMETER of the ROBOT (i.e. BUMPERS must wrap entirely around the ROBOT).

The visual is to wrap a piece of string around the robot. They should have used a rubber band (and I told them so during the offseason). That string will show you the bumper perimeter. You need bumpers on 100% of that string. No bumpers over the cutout, no 100% coverage, fix it before you can play.

[SteveGPage]

Just last night I commented to another mentor - "You know, I haven't seen the rash of bumper questions, like in previous years. Maybe they are starting to get it!"

Maybe they just haven't done their chasis designs, yet!

Steve

[TedG]

For our robot this year we wanted to have an inner angle so that when we go to deploy the minibot we could hit it with the inner angle and always be straight on to the pole is this allowed?
According to the rules "BUMPERS must provide complete protection of the entire FRAME PERIMETER of the ROBOT (i.e. BUMPERS must wrap entirely around the ROBOT). As part of the 100% coverage, BUMPERS must protect all exterior corners of the FRAME PERIMETER. For adequate protection, a full segment of BUMPER must be placed on each side of the corner"

but it also says "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 STARTING CONFIGURATION
will always have the BUMPER be the first thing to contact the wall."

so reading these over we should be able to do this but we wanted to be sure before we just started cutting and welding

[GaryVoshol]

Interior angles and concave sections are not allowed in the FRAME PERIMETER - see that definition.

BUMPERS may span short segments that do not have a physical frame member along the FRAME PERIMETER - see <R07-K>.