Traffic-light feedback
Green, yellow and red. Students know exactly where they stand without a teacher raising their voice.
IoT · ESP32 · Capstone project
A calmer classroom, one light at a time.
Hush listens to the room, estimates the noise level in real time and shows it on a simple traffic light, so students can see when it's time to bring it down.
Room 204 · live
48 dB
quietmoderatetoo loud
All good, keep it up!
Everything a classroom needs.
Nothing it doesn't.
Smart escalation
Smoothing, hysteresis and timed warnings mean a dropped book never sets it off.
Privacy first
No live listening and no continuous recording. Only a 5-second clip on major events.
Offline first
Events and readings buffer to the SD card and sync when Wi-Fi is back.
On-device admin
Wi-Fi setup, thresholds, timers, LED brightness and diagnostics from any phone.
Cloud dashboard
Incidents and clips sync to the cloud with role-based access for staff.
How it works
- 1
Listen
An I2S digital microphone samples the room continuously.
- 2
Measure
The ESP32 computes an estimated sound level and smooths it.
- 3
Signal
The traffic light changes; warnings escalate while it stays red.
- 4
Report
Incidents are logged with time and severity, then synced.
Built to respect students.
The device never streams audio and nobody can listen in. It only measures loudness. When noise stays at the major level, it saves exactly five seconds as evidence, and nothing more.
- No live listening
- No continuous recording
- Event-triggered 5-second clips only
- Role-based access to recordings
Inside the box
- ESP32
- INMP441 I2S mic
- RGB traffic light
- MicroSD card
- RTC module
- Speaker + MP3
Ready to give it a try?
Firmware, web UI and setup notes are all in the repository.
Get the source