I am trying to come up with a design that would track the position of a wire. The wire will have a permanent magnet attached to its tip. I will use a electromagnet to move the wire in only 1 dimension. Here is what I was thinking.... I would put a stationary aluminum plate some distance from the electromagnet. The wire with the permanent magnet will be placed in the middle. The wire will be moved according to capacitance. What kind of circuitry would be need to "measure" the value of capacitance? The capacitance value will tell me the position of the wire.