This biofeedback setup uses an EMG sensor to represent muscle tension as a series of beeps and allows you to train your body to adjust muscle tension at will. In short, the more tense you are, the faster the beeps become, and the more relaxed, the slower. Using this device you can learn how to regulate your body to speed up and slow down the beeps; hence increasing and decreasing muscle tension. With some practice, you will have enough understanding of your body to be able to control muscle tension without use of the device. This is cool because it allows you to consciously control a part of the body you would not normally be able to otherwise sense or easily control.
I set mine up to monitor the muscles in my shoulder and neck that are responsible for tension headaches, but you can place them on just about any muscle group. I recommend experimenting with the placement of the sensors and seeing what is possible.
Step 1: Go get stuff
You will need:
- An EMG sensor
- Electrode cables
- An Arduino
- A +/- 5V regulated supply board***
- 3-Pin female header
- 9V battery snap
- 1/4" stereo jack
- Headphones with 1/4" plug
- European-style terminal strip
- Red, green, and black 22 awg solid core wire
***+/-5V is the bottom range for the sensor board. I found two 9V batteries wired in series worked better than this board. The single red Wire is +9V, the junction where the two batteries meet is ground, and the lone black wire is -9V. Alternately, you can get a +/-12v mini board from Futurlec. However, I have not tried this.
Step 2: EMG Board
Assembled the EMG board with the parts provided as labeled.
Note that it comes with 5-band resistors and those are read differently from the typical 4-band resistors.
Step 3: Prepare the cables
Take a razor blade or other sharp object and cut around the circumference of the center of the cables plug to expose a metal tip.
Repeat this for all three cables.