Hey! I helped run it at Nationals in '06; my (one of many) boss dreamed this one up. passing the question along to him and he should (no promises, since I'm not him) get back to you.
From the three times I've helped him run it, the 7 meters isn't the problem. It's getting the thing to return to the same spot. Bad aim seems to correct itself, but getting it to stop right back where it started from. . . . .
best one i ever saw was the one in '06 that almost went into an open elevator. i was prepared to follow it if it did!
Uncle Fester, Maker & Fiction Science Writer
The Misadventures of the Electric Detention
The Revenge of the Electric Detention
The Curse of the Electric Detention
>> Three full-length adventures, 26 short stories and counting!