[EricH]

Originally Posted by Radical Pi

Exactly that though: string around the Bumper zone. It says nothing about pulling the string back for any gaps, leaving the frame perimeter as the outside edges of the robot. Since <R07-M> says it must be backed by the robot itself, it leaves the gap out

The string itself is the frame perimeter.

Originally Posted by Section 7

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.

Therefore, any gap in the robot frame in the bumper zone must have a structural support running over it to support the bumper.