Aerospace Eng in Foreign Electromag Land, gulp.

Hi there. You are going to need some strong magnets! The prposed hinge system sounds a little dubious to me. If you are familiar with the vibration tables in environmental testing labs these generally use a "moving coil" exciter on each axis. These are effectively just like the innards of your hi-fi loudspeaker, but on a giant scale and without the speaker cone. You should be able to make some quite resonable smaller scale ones if you use the cardboard tube from the centre of a toilet roll.

You don't say what kind of motion you are expecting from the shaker, i.e. sinusiodally, or what? If you just want it to flip-flop back and forth then you can make quite a simple driver circuit, but if want it to follow a waveform you will need quite a large power amplifier.

Hope that helps.....

Thanks Brian,

I appologize it's sinusoidal. If I recall my speaker classes then we are talking about a coil and perm mag config? what do we use for a signal driver?

Heck maybe a motor and piston set up would be more effective. Although, it would increase the complexity of the item.

B

For 10 Hz, I might try a mechanical cam/motor. Maybe an old sewing machine? Otherwise, for a electro-dynamic type, try a old powered subwoofer, or one of those power amps used for car speakers - like used in the annoying cars that you find at a traffic light with all the body panels rattling! For either, check a local thrift shop or pawn shop. For the magnetic drive element - can't think of anything that might be adapted easily other than an old sub woofer speaker.

That's why I luv you guys...you got great ideas! Thanks Comcokid and BrianG.

B

Simply an universal motor ( e.g. sewing machine motor, as mentioned) with an excentric mass and speed control.


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