Signed. There are more effective means of clearing a path, the best to be have someone who stands 5 feet or so in front of the cart tapping peoples shoulders as a warning.
After a short time at competitions hearing about how a robot is moving the entire competition away from where you are, the next time you hear it behind you, you tend to ignore it... Its pretty bad how by the end of the first day, what you use to identify movement of heavy robots are generally ignored because its hard to tell where they are coming from when they are all the same loudness.
I find the best is to be just a bit on the quiet side. Its so different from everything else that it catches the attention better.
Also, you may want to add a limit on the DJ's volume, because if its too loud, its difficult to hear yourself think let alone hearing "Excuse me, I have a robot behind me."

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"I want you to lose [by] the most you can!" ~Mr. Hepfer at Breakaway Champs. [Curie Match 100]
RoboDawg Alumni, 2009-2012
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For lack of being allowed to put them up top here are all my kids!