Whispering “Shhhhhh” is not the most effective way to get people to shut up. Especially in public spaces, and especially in public libraries.

So, let’s shut their mouth with a sense of guilt. This light is installed in the library. It detects noise, and as the noise increases, the luminance decreases. If you’re speaking too loud in the library, the room gets darker and darker. Eventually, everyone in the room won’t be able to read. Is that what you expected? Probably not, And because you are now unexpectedly the center of attention in this darkening room, pieced of hundreds of readers’ eyes filled with fire, your sense of guilt will skyrocket and you’ll definitely shut up. After the room becomes silent, the light will turn back on. Then, everyone can read in silence, and everyone wins :))))))))

Shopping List:
Arduino

3D-building software

3D printing machine

Electret Microphone Amplifier

super bright LEDs

Step 1: Build It and Print It

Build a 3D model first.

Make sure the size of the model can fit all your Arduino

Step 2: Assemble Your Material

Step 3: Arduino

Coding:

const int sampleWindow = 50; // Sample window width in mS (50 mS = 20Hz)
unsigned int sample; int brightness = 255; int led[] = {2,4,7,8,12,13}; void setup() { Serial.begin(9600); } void loop() { unsigned long startMillis= millis(); // Start of sample window unsigned int peakToPeak = 0; // peak-to-peak level unsigned int signalMax = 0; unsigned int signalMin = 1024; // collect data for 50 mS while (millis() - startMillis < sampleWindow) { sample = analogRead(0); if (sample < 1024) // toss out spurious readings { if (sample > signalMax) { signalMax = sample; // save just the max levels } else if (sample < signalMin) { signalMin = sample; // save just the min levels } } } peakToPeak = signalMax - signalMin; // max - min = peak-peak amplitude double volts = (peakToPeak * 5.0) / 1024; // convert to volts brightness = map(volts, 0.3, 5, 255, 0); for(int i = 0; i < 6; i ++){ analogWrite(led[i], brightness); } Serial.println(volts); }