Minimalist ultrasound levitator
This code is a simplification of the minilev.ino Asier Marzo version (http://www.instructables.com/id/Acoustic-Levitator/).
This algorithm is optimized to use only a pair of ultrasonic transducers facing each other and an Arduino Nano, using software interruptions of an 80 kHz timer, and toggling the state of the pins.
If using HC-SR04 sensor transducers, be sure to use the emission transducers with a T marked on the back.
A0 A1
_|___|_
| + - |
|_______|
|
1.5 cm | * Node 1
| * Node 2
| _______
| + - |
|_______|
| |
A2 A3
Connect one transducer to A0 and A1; and another transducer to A2 and A3.
Put the transducers opposite to each other to levitate a particle between them, it is easier to place the particle with a metallic grid.
You can use 3D-printed case designed by IB-as https://www.tinkercad.com/things/9uXNA47qORj#/