If this is a top view, the edge of your FRAME PERIMETER is the 24 inch dimension and therefore you have to cover 8 inches on either side. The bumper shown would not be legal.
See this Q&A
If in doubt, imagine pulling a string all the way around the outside of your robot. This defines your FRAME PERIMETER. Each of the sides of string now needs to have at least 8 inches of bumper on it, and each end of each bumper piece needs to be supported (at least 1/2 inch per R26).
-matto-