I think what you are talking about is this. (16"x36" contact base)
The red areas are the "blocking spaces where balls can't be thrown. All measurements are ballpark (within 1-2" accurate, Proof of Concept)
The robot fits in the "box" and hugs at least half of the trailer. Weight issues might be a problem, but if you make the shroud light enough and place the batteries and heavy stuff in front you might be OK.