Introduction: AURA - Audio Reactive Artistry
Hello, and welcome to AURA.
Music and sound inspire many people, including me and my creative work. For one of my artistic works I wanted to extend the experience of a piano concert by moving objects in the concert hall reactively to the music being played. I wanted to read the music depending on the volume level and frequency and send it via a microcontroller to a motor controller. Since I couldn’t find a tutorial that fits my needs, I designed my own setup, which I would like to share with you on instructables or detailed on my website www.alexrex.de/audioreactive/ .
My webpage shows you two different setups to read out sound and how to send this information as impulses to motors, such as steppers or servos. The basic idea of each setup looks like the schematic you see here.
In the following I will explain you how to drive stepper motors audio reactive. This SETUP is called AURA (Audio Reactive Artistry) SETUP B.
... uses a teensy and an audio board to read frequencies out of the audio input and send impulses to stepper drivers to controll powerfull stepper motors. For these components you will pay ~250 € and it will take you some more time to wire all together. This will provide you with a solid audio reactive motor control system, that can handle art exhibitions or little installations on festivals or concerts.
I used a single Teensy 3.5. With this setup I can easily define my own frequency bands and don't have to use the predefined frequency bands from the Spectrum Shield.
Let us have a look at the components needed, to set up a advanced audio reactive motor control:
This component is the heart of the setup.
Audio Adaptor Board for Teensy 3.0 - 3.6
This adaptor will provide the Teensy 3.5 with stereo line-level input.
Two Breadboards for Arduino
The breadboard has a uniform grid on which the components and power supply are connected with wires. We need two of these small boards to allow the teensy audio board combination setup to be placed.
Dupont Jumper Cable
There are different versions of these cables, which differ in their ends. There are male-male, female-female or male-female ends. It is best to have enough of all variants in stock. Furthermore it is advisable to leave the colour of the cable the same for each signal.
Stackable Header Kit for Teensy
To connect the Audio Board to the Teensy.
External Stepper Motor Driver for A4988/DRV8825/TMC2100
For every stepper motor we will need one of these boards. But before we can use this board, we have to remove one resistor and add a new 4.6 kOhms resistor on the flipside. You will find a detailed tutorial for this rebuild down in the schematic.
4.6 kOhm Resistor
For rebuilding the Stepper Driver Board.
Stepper Driver TMC2208
This driver controls the motor and makes its rotation ultra quiet, which is pretty useful for sound installations. For each stepper motor in the final setup we will need one of these drivers.
Stepper Motor Nema 17
There are different types of Nema 17 Motors available. All of them are strong and precise.
Micro USB-B Cable
Connecting computer and teensy.
Step 1: Rebuild Driver Board A4988 for TMC2208
Before we can start to wire everything up, we have to rebuild the stepper driver board, so it will work togehter with the ultra quiet TMC2208 driver. At first remove the R1 resistor on the front while using needle-nosed pliers or hit it hard but carefully with a small screw driver.
After this solder a ~4.6 Ohm resistor on the back, connecting GND (ground) and EN (enable).
After you finished this rebuild, connect your 12-24V power supply to the setup. Please pay special attention to directions of the currents! Otherwise you will burn your TMC2208 very fast. Finaly you have to set the right current setting on your TMC2208 driver while turning the potentiometer and measuring the voltage simultaneously. Please find detailed information how to this in this little guide or in this youtube-tutorial.
Step 2: Wiring
Connect your components
Please connect the parts as shown in the drawing and the pictures here. I fitted all elements inside a box, to keep them save at the art installation in the galleries.
Step 3: CODE
Please find attached two files with the code for the AURA SETUP B. One file is the PDF to transfer the code by copy and paste into your arduino project. The other file is the *.ino Arduino file.