This experiment use human infrared sensors to detect if anyone is moving around the sensor. If yes the buzzer will make an alarm.

Material:

1.    arduino

2.   bread board

3.   LED

Note: you can redeem it in PCBWay, please support me register by this invited PCBWay link

Here is the connection diagram:

Here is the code:

int Sensor_pin = 3;

int ledpin = 11;

void setup()

{

  pinMode(Sensor_pin, INPUT); // Set the human infrared interface as the input state

  pinMode(ledpin, OUTPUT);

  Serial.begin(9600);

  Serial.flush();

  Serial.println("Ready");

}

void loop()

{

  int val = digitalRead(Sensor_pin); // Define parameters to store the state read by the human infrared senso

  if (val == 1) // Buzzer make alarm if someone is detected

  {

    Serial.println("There is sb moving");

    digitalWrite(ledpin, HIGH);

  }

  else

  {

    Serial.println("There isn't sb moving");

    digitalWrite(ledpin, LOW);

  }

  delay(100); // Delay 100 milliseconds }