Well, I need a rotating disk consisting of two metalic plates seperated by a dielectric, effectively creating a capacitor that is charged via its rotation (exact mechanism is not important) and what I really want now that I think about it is a fast cutoff for the discharge, ie a mosfet. Since the disk is spinning, it makes it dificult to make electrical connections to it, if I can house the electronics on the disk itself, all the better. So I want it to discharge maybe halfway through its total charge then cut off as fast as possible, then reset so that it may be recharged.
Actually, while im typin here, does anybody know of a good spray on dielectric with a high dielectric constat? I want this disk to have as much capacitance as possible.