On Thu, 31 Mar 2005 12:00:37 -0600, you wrote:

>> I need to wiggle a thin wire. It will require very small movement, a
>> few thousands of an inch, and the wire end will be free so there 
>> will be very little force required. I would like to use only a few mA 
>> at 5volts or less.
>> 
>> I have looked at muscle wire and such. Are there any other ways
>> to do this?
>
>I'm thinking about the fact that current flowing through a wire
>immersed in a uniform magnetic field produces a lateral force on
>the wire.  Could you place a conductive joint halfway along the wire
>such that it forms a fulcrum, then run your 5-10 mA through the wire
>with a powerful fixed magnet underneath, such that the lateral force
>bows the wire?  The result would be that the end of the wire would
>move laterally in the opposite direction; the advantage here is that
>by altering the direction of the current, you can change the direction
>of the wiggle.  In fact, by flip-flopping the current flow, you could
>(probably) create a harmonic effect to get the end of the wire going
>quite vigorously.  I'll try to make a small diagram and get it online...
>
>Mike H.

Peizoelectric actuators are commonly used for this type of thing (are you trying to make a scaning
tunnelling electron microscope?). You could probably improvise someting out of normal piezo discs. 



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