[icewolf08]

Probably the easiest and least expensive solution is to make them hand operated olio style drop. So you would have the fabric attached to a drum that the fabric can roll up onto. You would then have control lines from each that you can pull one way to roll them up and one way to unroll them. You would then direct the control lines to either side of the stage and probably have 4 operators.

To do it with motors would require a lot of work. You would have to find variable speed reversible motors. You would probably need some kind of gear reducers to get the drops moving at a manageable speed, and you would need a way to control them. Though it is doable, it is probably more costly and time consuming than it is worth.