-:Light On/Off By Clapping:-

So, basically in this project, I have made system related to home automation so for this project we need:-

Arduino Uno

Relay

Mic Module

Bulb

so basically connect Vcc to +5volt

Gnd to Ground pin of Arduino

and data pin to digital pin you can use any digital pin of you Arduino and configure to your code

#define signalToRelayPin 13
#define sensorPin 2

int lastSoundValue;
int soundValue;
long lastNoiseTime = 0;
long currentNoiseTime = 0;
long lastLightChange = 0;
int relayStatus = HIGH;

void setup() {
  pinMode(sensorPin, INPUT);
  pinMode(signalToRelayPin, OUTPUT);
}

void loop() {
  soundValue = digitalRead(sensorPin);
  currentNoiseTime = millis();

  if (soundValue == 1) { // if there is currently a noise

    if (
      (currentNoiseTime > lastNoiseTime + 200) && // to debounce a sound occurring in more than a loop cycle as a single noise
      (lastSoundValue == 0) &&  // if it was silent before
      (currentNoiseTime < lastNoiseTime + 800) && // if current clap is less than 0.8 seconds after the first clap
      (currentNoiseTime > lastLightChange + 1000) // to avoid taking a third clap as part of a pattern
    ) {

      relayStatus = !relayStatus;
      digitalWrite(signalToRelayPin, relayStatus);
      lastLightChange = currentNoiseTime;
     }

     lastNoiseTime = currentNoiseTime;
  }

  lastSoundValue = soundValue;
}

EXPANDED TECHNICAL DETAILS

Acoustic Event Impulse Logic

A practical and fun home automation project that provides hands-free light control using the acoustic signature of a human clap.

• Envelope-Follower Signal Analysis: Uses a high-gain microphone module. The Arduino ignores steady background noise and only triggers when it detects a sharp "Spike" (High Amplitude, Low Duration) characteristic of a clap.
• Double-Clap Verification Kernel: To prevent false triggers from speech or music, the firmware requires two claps within a 500ms window. The Arduino times the interval between spikes to verify a "Double-Clap" event before toggling the relay.

Performance

• Verified with Arduino IDE: Coded with a robust state-machine that ensures the light never "Flickers" or behaves unpredictably during loud environmental sounds.