> IIRC the "drop tower" sort of rides at amusement parks use eddy
> current brakes also,  beefy permanent magnets mounted on the car,
> copper/aluminum fins mounted on the tower. Nothing moving to fail,
> nothing that wears out

I do believe I've seen that on a Discovery show, thanks for reminding
me. I think though that eddy currents are, AFAIK, made by disks
moving past each other in the same plane, eg similar to the tuning gang
in a radio, without ferromagnetism

I don't think the same plates would be an effective brake if they move
perpendicularly (agh, that's twice I've had to type that !!) to each other

Which is why I'm looking at permanent and electromagnets. Maybe it'll
lead somewhere, maybe it won't

Joe
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