Help with my linear resonance actuator, solenoid, piezoelectric motor, or ERM question

[CHRISGLIB]

I am attempting to design/make a vibrating platform (think foot massager) that has the following characteristics:
1. Vibrates at a frequency between 12-25 Hertz
2. Has an amplitude (displacement) of less than 4mm. Ideally somewhere between 1-4 mm.
3. Has an acceleration of less than 1G. Ideally between .3G's and 1G.

In a perfect world, this platform would only vibrate up and down and not side to side. But as I read more, it sounds like it may have to do both.

I'v done as much research as I can regarding linear resonance actuators, however these all seem to have higher frequencies than what I'm looking for. I then researched linear solenoids, but these seem to have lower frequencies than what I'm looking for.

I'm not sure if a piezoelectric motor would work, but they seem to vibrate a pretty high frequencies also. I vibrating ERM motor may also work but I'm having difficulty finding one that fits my characteristics.

I would greatly appreciate any advice or feedback on if this is possible.

 

[sreid]

I'd suggest a Universal Mot phase controlled SCR (like a light dimmer).

https://en.wikipedia.org/wiki/Universahttp://www.eng-tips.com/viewthread.cfm?qid=415607l_motor

 

[sreid]

https://en.wikipedia.org/wiki/Universal_motor

Oops!

 

[mikekilroy]

This is perfect application for a PM linear servo motor. I would recommend you contact some mfgrs of them such as kollmorgen.com and others. We have done many similar performance 15-25hz oscillating motions as you describe.

They will assign an application engineer to walk you through their motioneering (tm) free software to model this and it will pick your components required.

Google "linear servo motor" and you will find folks that can help do the application work for and with you.

http://www.KilroyWasHere<dot>com

 

[sreid]

http://mamcomotors.com/b-motors