Parametric Acoustic Levitator

thingiverse

UPDATE 11/27/2019: I've completed this project. All parts, including the top cover and electronics base, are now available. Video in action [here](https://www.youtube.com/watch?v=uWjfwIOMlY8). Official home here: https://github.com/rsheldiii/ParametricLev ## What is this project? This is a Parametric Acoustic Levitator that powers the needs of 16mm drivers, aka BigLev. It works by creating 3d standing wave patterns in the air, allowing objects with a maximum density and size to be trapped in high pressure nodes. It uses transducers, which are just speakers that sometimes go way above frequencies the human ear can hear. The goal was to levitate small 3D printed objects, and do so in a parametric and hopefully prettier package. ## Parametric you say? While the design is indeed parametric, there's still a lot of hand-editing required to fit the correct / maximal number of transducers; the code attempts to make useful decisions for you, but it's not always great at it. In order to keep the math simple, transducer placement is done assuming you want 44000KHZ, so that gets you ~4.5mm. Increasing voltage increases the density of objects you can levitate. ## Parts list For a BigLev, please print: * 2 BigLev-half.stl * 2 BigLev-press-fit-shunt.stl * 1 BigLev-top.stl * 1 BigLev-bottom.stl You can get away without the shunts by gluing the two halves together, but I've found it very helpful to be able to vary the distance of the transducers from each other. There should be a "best" distance, but some items prefer different distances than others. ## Assembly Proceed to the Github page for assembly instructions: https://github.com/rsheldiii/ParametricLev You can piece together how to wire this by following the two guides listed above. Note that the tractor beam guide is only used for the wiring of the electronics; follow the wiring on that guide until you get to the outputs of the stepper motor driver, then switch to the original guide (positive / negative pairs powering each side). Couple notes: 1. You do really have to test the transducers, the ground pole is wrong half the time. 2. This print has extreme overhangs, so make sure you can dial in your supports. 3. You can melt the coating off the magnet wire with a soldering iron or lighter, and then I found looping the wire around the peg before soldering was a great way to get a good fit and keep things in place. 4. The size of objects you can levitate is always limited by half the wavelength of the sound you are generating. 5. Similarly, the transducers want to be a specific distance away from each other, so you may have to cut off / shim the side sponsons to get good levitation. 6. I found that teabag material made a good spoon to hold things you want to levitate. If there are any questions let me know!