[MattLi]

Ah now I see what the application is. I'm going to argue that the electromagnet can still be considered dangerous. I haven't done any research, but isn't the power of electromagnets determined by the amount of current run through them? Getting close to another robot with your arm could still disable it. And please talk to your programmers. Usually programmers + electromagnets = a painful debate about why there will be ABSOLUTELY NO MAGNETS ON OUR ROBOT. (Trust me I tried to argue for a magnet in 2006 aim high that would stick to the diamond plate when we rolled down)

There are much better ways to open and close an arm. Pneumatics, motors, you take your pick. An electromaget would also take up electricity. With that new battery I'm not sure that the battery could put out enough juice to sustain your "arm closing mechanism." Your opinion is your opinion. Good luck during the season. If you guys do build this please email me. I would like to see how it would work.