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I've been working on a little prototype - it's kind of a creative interpretation of a heart beat. The piece is made from an electromagnet, a neodymium magnet, some springs, and acrylic -

Electromagnet off: The attractive force of the neodymium magnet brings the magnets closer together, but the compressive resistance of the springs prevent the magnets from touching.
Electromagnet on: The repulsive force causes the neodymium magnet and plastic panel to shoot up.
Electromagnet off: Gravity brings the neodymium magnet down.

Everything is working well, but I'd like a little more "oomph", specifically the vertical distance the top panel can travel. What are my options?

I've considered using stepper motors to raise and lower the top panel, but I'd like to stick with the magnets because they can be "self correcting" in this scenario. The final version of this piece will be touched. If someone presses down kind of hard, the beat effect will be temporarily disabled, but can continue as soon as someone removes their hand.

* Would a larger electromagnet make much of a difference?
* Has anyone here tried something like (patent link -
* Instead of using a neodymium magnet, what if it was a steel cylinder mounted to the bottom of the top piece of plastic. When the attractive force of the electromagnet kicked on, the steel cylinder would surround the electromagnet.

The video posted is just a prototype and I'd definitely be willing to rethink the physical structure of the device if I can get more magnetic force. Thanks for any help you can provide.

Links for reference
Electromagnet - ... r=8-4&th=1
Neodymium Magnet - ... UTF8&psc=1
Electromagnet field strength is proportional to the number of turns of wire in the coil and the current flow.

With your existing setup, you could increase the voltage of the electromagnet power supply, which increases the current flow. However, avoid using a voltage so high that the coil starts to overheat. Heating will also depend on the duty cycle, i.e. the fraction of time the coil is powered.