Better Motion Through Electrostatic Actuators

If you want something to move with electricity, odds are you’ll be using magnets. Deep inside every servo, every motor, and every linear actuator is a magnet and some coils of wire. There is another way of making things move, though: electrostatics. These are usually seen in tiny MEMS devices, and now we have tiny little electrostatic speakers making their way into phones and other miniature devices.

For [Nathann]’s Hackaday Prize entry, he’s building electrostatic actuators on the cheap, and not just tiny ones, either. He’s building ‘human’ scale electrostatic devices.

The reason electrostatic devices are usually very small is simple: the force of any actuator is dependent on the distance between the plates and the voltage. Moving the plates closer together is right out, or else they would be touching, so the solution to building bigger electrostatic actuators is increasing the voltage. [Nathann] is doing this with a cheap boost converter that’s actually sold as a taser module. These modules are small, output about 800kV, and cost around five bucks.

The prototype for this project is basically a 3D printed box with intersecting fins. These fins are covered in aluminum foil, and the box is filled with oil to prevent arcing. Will it work? That remains to be seen, but this project is a great example of what can be done with some creative part sourcing, a 3D printer, and a tiny bit of know-how. It’s some of the best work the Hackaday Prize has to offer, and we’re amazed that [Nathann] put in the work to make this happen.

10 thoughts on “Better Motion Through Electrostatic Actuators

    1. 800 kv is unlikely to say the least.
      I bought a couple of those cheap HV transformers which were advertised as, “1,000,000 VOLTS!”, but could barely put out a centimeter long spark, so probably 10 kv would be more realistic.

  1. As one who has done some HV mucking around. 15KV can jump about an inch and a half and once the spark as started the plasma conducts better than the air, it can span 5 to 6 inches. Look at any jacob’s ladder based on a neon sign transformer. A quick bit of reading turfed up that 200KV should be able to jump 8″ or so of air. Note that the above are with pointed ends, and pointed at each other. 800KV is a lot of voltage. It is hard to get static charges that big because of their high impedance. The parasitics start to bleed them off. I am sure someone, someplace has a source that big but god only knows what they use for insulation at those voltages. It may be more like ham radio flatline and you just keep a conductor suspended on (clean) soda glass rods. I do not see it being easy to generate, controle, or work with.

  2. “We don’t know if it works, but here’s an article.”
    This sounds like the perfect Hackaday article to me…
    Living on the fringe of things which may, or may not be possible is the essence of what this should be.
    Who cares if it pans out or not, it is the documented attempt that others can build on counts.

    1. Call me old-fashioned, I like to read about stuff that actually works, but I see your point in the last sentence.

      I would still suggest that claims of 800,000 volts require extraordinary evidence.

Leave a Reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.