See this link: http://www.chiefdelphi.com/forums/showthread.php?threadid=43369 <S03> The SHOOTING MECHANISM must remain inside the ROBOT - Any mechanism used to throw balls must be contained within the original 28" x 38" x 60"starting envelope of the ROBOT and must be shielded such that the mechanism cannot make contact with other ROBOTs. A ROBOT that violates this rule will be considered unsafe per <S01>. This now includes a "roller" type sweeper such as ours and it must be shielded per S03. J