Robot Design: Frame Perimeter?

[IamMisplaced]

We are wondering, the rule, and revision to the rule, is relatively vague about what constitutes a frame perimeter. We are design a "snow plow" directly into our robot, but if the balls go into that plow, is that considered inside the 3" perimeter rule? Or, does that only mean literaly under the robot?

[DonRotolo]

I can't say; I think the rule is pretty clear:
FRAME PERIMETER – the polygon defined by the outer-most set of exterior vertices on the ROBOT (without the BUMPERS attached) that are within the BUMPER ZONE. To determine the FRAME PERIMETER, wrap a piece of string around the ROBOT at the level of the BUMPER ZONE - the string describes this polygon
Got any string?

If any ball can go more than 3" inside that string, it's not allowed.

[MrForbes]

It might help if you show us some drawings of your planned robot design. I don't really understand your description.

Show the robot from a couple different views, or an isometric drawing.

[IamMisplaced]

The thing is, with the string thing, what if there is a gap? Imagine an H, does that include the inside parts of an H?

[MrForbes]

The string goes across the gap, so the FRAME PERIMETER also goes across the gap. But the bumper rule says you need to protect both sides of any outside corner with bumpers. Basically you cannot have a notch in your bumpers.

There have been a few threads discussing this already.

http://www.chiefdelphi.com/forums/showthread.php?t=79945

[IamMisplaced]

BUT, what about revised section <R19>, and in effect diagram 8-5, it only says the robot frame, which is within the bumper, and why can't the frame be something but a perfect polygon and no inlets. Also, in the other forum, they said that it would be legal because the bumper is covered by everything and the balls wouldn't be inside the robot.

[GaryVoshol]

The entire bumper length must be backed up by frame members. (<R07>) That's why there must be a complete frame all around the FRAME PERIMETER.

[MrForbes]

It would be very helpful to see drawings of what you're trying to do.