Bumpers - Rule R08 Robot Perimeter

[FRC766]

We read Rule 08 regarding the construction and installation of bumpers and we are clear on the part that states “STANDARD BUMPERS must protect a minimum of 2/3 of the perimeter of the ROBOT within the BUMPER ZONE”. We are contemplating using a robot design with a wide and deep frontal opening to receive and hold the ball. The width and depth of the opening is 17 and 20 inches respectively. Would the 17 inches be included in calculating the robot perimeter? We think the 2/3 is intended to accommodate openings and such but in our case the opening depth is so deep that it is just not feasible for another robot to make contact with the back of the opening. I think you can see where we are headed with this design concept. The high bumpers would not permit us to come up under the ball in the region around our opening.

[FRC190]

The rules state that the bumpers must cover 2/3 of the perimeter of the robot. At what height is the perimeter measured, and how is it determined? If the robot is approximately rectangular, is the perimeter simply twice the robot's maximum width plus twice the maximum length?

[FRC766]

Re: R08 about bumpers protecting 2/3 of the robot's perimeter:

Interpretation of this rule is clear when the robot is a typical rectangular or convex polygonal shape, where any point in the outside perimeter might contact another robot. However our robot will have a large "notch" in the front, some 20" wide and 17" deep, that would not be contacting other robots, because some other portion of the frame would contact first. By "perimeter", does the rule apply only to the exterior perimeter of a robot, which could contact other robots, or would our "interior" perimeter length also have to be counted, even though there is no potential for bumping there?

P.S. We initially posted this question on Monday 1/14 but haven't seen a response yet, so we are afraid our original post may have gotten lost. Please reply as soon as you can, as this is a key factor in our design...

[FRC190]

How is the perimeter of the robot determined for the purposes of bumper coverage?

[GDC]

Our apologies for the rule's ambiguity.

The intent of the rule was for the bumpers to cover at least 2/3 of the exterior perimeter of the Robot. If the Robot is somewhat rectangular, the perimeter is twice the Robot's maximum width plus twice the Robot's maximum length. For example, this would apply to the rectangular external perimeter of a U-shaped Robot.