[Tom Line]

Originally Posted by Ether

Of course. There is more than one way to skin a cat.

Two-roller ball magnet designs in which the ball does not rotate continuously when possessed have already been described in this thread:

http://www.chiefdelphi.com/forums/sh...0&postcount=63

http://www.chiefdelphi.com/forums/sh...2&postcount=60

http://www.chiefdelphi.com/forums/sh...9&postcount=56

Question for you: is the lower bar in your design fixed or is it free to spin?


~

As you said, there's always more than one way to skin a cat (I'm going to have to look up where that euphemism came from: it isn't the more pleasing when you think about it ).

However, "trapping" the ball, as it were, rather than spinning it, makes a much easier system. You don't have to worry about roller speed, you don't have to worry about moderating your back up or turning speed, you don't have to worry about the ball rolling off sideways when you turn, you don't have to worry about differing ball surfaces or differing carpet cof's.

In fact, all you need is a small motor driving the top bar and you're set. That's why we chose that system.

I've seen excellent backward-ball-spinnering systems too, however we found that going that direction took a more powerful motor that we wanted to use elsewhere, as well as all the considerations I listed above.