I know it sounds like a basic question, but it is keeping my team up at night. Is frame perimeter a physical object or a non-physical area? We can all agree that the frame perimeter is a rectangle whose dimensions are the greatest length and width of the non extendable parts of your robot. The rules state that the bumpers must fully enclose your frame perimeter. According to my definition, if the frame perimeter was a physical object, then the bumpers would have to physically touch the longest and widest sides of your robot. If frame perimeter were non-physical then the bumper has to enclose the imaginary box formed by your longest and widest side.
As an analogy I want you to picture an opened umbrella as the robot. If the frame perimeter where physical, this would mean that the umbrella must be 2-10 inches off the ground and have the bumpers attached to it. If the frame perimeter was not physical, then the umbrella can be held high in the air as long as there was bumpers at ground level matching its outline.