Introduction: Ultrasonic Array
In this project we will show you how to build a phased-array controller and a flat array of 8x8 elements. These systems can be used for acoustic levitation, haptic feedback or directional speakers.
This is quite a complex project so I would recommend a little bit of knowledge on ultrasonics, computer science and electronics.
Do not forget to check the other Instructables for more information www.acousticlevitator.com
More detailed information in our open paper: http://ieeexplore.ieee.org/document/8094247/
All the detailed steps are in the attached video.
Step 1: Gather the Components
The source code is available here: https://github.com/asiermarzo/Ultraino
You will also find the STL files for the 3D printed arrays and the AI files for the laser-cut arrays.
The PCB files for manufacturing are also there here I recommend to use PCB Shopper to look for a cheap manufacturer. The dimensions of the board are 50.8mm by 67.31mm and it has 4 layers. It would be a good idea to order an stencil if you do not want to solder the components by hand.
The BOM can be found here.
Step 2: Assemble the Driver Board
You can solder by hand, or use solder paste and a reflow oven. I am not the most proficient SMD solderer, there are lots of goods tutorials on the Internet.
The code for the Arduino Mega is here
Step 3: Assembling a 8x8 Flat Array
Step 4: Single-sided Levitation
Step 5: Standing-wave Levitation
Step 6: Haptic Feedback
Step 7: Directional Speaker
I used this audio amplifier TDA7492P but anything that you can find will probably do the job.
* This is just a quick way of getting a directional speaker, the sound quality is not great and it is not very powerful. I am working on a dedicated directional speaker that will be released soon.