Overview


I built this wearable device to give a reminder when I slouch. It sounds a buzzer if slouching lasts at least seven seconds. I chose that delay so brief movements wouldn't trigger an alert.

I used the existing SEFR algorithm with the micromlgen library, following Eloquent Arduino's guide. I trained the classifier on 600 samples: 300 slouching and 300 non-slouching.

I lowered the Arduino Pro Mini's clock speed and removed unused LEDs to reduce power use. The battery lasts up to about 4.5 days under ideal conditions. A power switch and charging module make it easy to turn off and recharge.

Pictures


Device viewed from above

Device viewed from below

Assembled device viewed from above

Assembled device viewed from below

Assembled device viewed from the side

3D printed enclosure

Power switch and indicator light

Charging indicator light


Demo


Turn up the volume to hear the buzzer.

Wearing the device


Schematic



Sequence Diagram



Code and Setup


The code and setup instructions are in my GitHub repository.