Burglar Alarm System — Arduino

Arduino Based Burglar Alarm System Demonstration

I successfully crafted a burglar alarm system using an Arduino Uno, incorporating an ultrasonic sensor SR04 and a buzzer. The Arduino controlled the system, the ultrasonic sensor detected movement, and the buzzer sounded a robust alarm in response. This DIY creation represents a powerful fusion of technology and innovation for enhanced home security.

Necessary Components

1. Arduino Board

515b4656ce395f8a38000000.png (551×405) (sparkfun.com)

2. Ultrasonic Sensor (SR04)

hc043.jpg (700×700) (digitalelectronics.lk)

3. Buzzer

3.5–5.5v-standard-active-buzzer-module-for-arduino-550x550.JPG (550×550) (flyrobo.in)

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4. LED light

light-emitting-diode-or-led-diode-with-individual-parts-and-structure-anvil-and-post.jpg (573×612) (istockphoto.com)

5. 100 Ω Resistor

121–5007–00_1.jpg (2571×2000) (plentymarkets.com)

Schematic Diagram

Schematic diagram of the above system

Arduino Program (source code)

// Arduino pin configuration
#define TRIG_PIN 13
#define ECHO_PIN 12
#define IND_LED 11
#define BUZ_PIN 9

bool entered;
long duration, distance;

void setup() {
  Serial.begin(9600);
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  pinMode(IND_LED, OUTPUT);
  pinMode(BUZ_PIN, OUTPUT);

  entered = false;
}

void loop() {
  // Clear sensor
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);

  // Generate 10 microseconds pulse to the sensor
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);

  duration = pulseIn(ECHO_PIN, HIGH); // in microseconds
  distance = (duration / 2) / 29.1; // in cm

  // Assuming door width is 10cm (If someone crossed the 10cm range, alarm will be raised)
  if (distance < 10) {
    entered = true;
  }

  // Alarm raises when someone crossed the range
  if (entered) {
    // Turn on alarm light
    digitalWrite(IND_LED, HIGH);
    
    // Generate 2KHz buzzer noise
    tone(BUZ_PIN, 2000);
    delay(500);
    
    digitalWrite(IND_LED, LOW);
    noTone(BUZ_PIN);
  }
  
  Serial.print(distance);
  Serial.println(" cm");
  delay(500);
}

Link to the simulation

Circuit design Burglar Alarm System - Arduino | Tinkercad