Bluetooth Controlled Police Siren Sound Circuit with Arduino

Nowadays, Arduino projects are very popular and they controls everything.

They are easy to build and they are useful for learning electronics.

This project is about Bluetooth Controlled Police Siren Sound Circuit with Arduino.

Arduino UNO is the main controller and Bluetooth module is used for wireless control.

With Bluetooth we can control lights and siren from mobile.

So, this project is useful for beginners and it is also good for demonstration and learning purpose.

Arduino Coding:

char data;

int red1 = 8;
int red2 = 9;
int blue1 = 10;
int blue2 = 11;
int speaker = 6;

void setup()
{
  pinMode(red1, OUTPUT);
  pinMode(red2, OUTPUT);
  pinMode(blue1, OUTPUT);
  pinMode(blue2, OUTPUT);
  pinMode(speaker, OUTPUT);

  Serial.begin(9600);
}

void loop()
{
  if (Serial.available())
  {
    data = Serial.read();
  }

  if (data == '1')
  {
    policeEffect();
  }
  else if (data == '0')
  {
    stopAll();
  }
}

void policeEffect()
{
  digitalWrite(red1, HIGH);
  digitalWrite(red2, HIGH);
  digitalWrite(blue1, LOW);
  digitalWrite(blue2, LOW);
  tone(speaker, 800);
  delay(200);

  digitalWrite(red1, LOW);
  digitalWrite(red2, LOW);
  digitalWrite(blue1, HIGH);
  digitalWrite(blue2, HIGH);
  tone(speaker, 1200);
  delay(200);
}

void stopAll()
{
  digitalWrite(red1, LOW);
  digitalWrite(red2, LOW);
  digitalWrite(blue1, LOW);
  digitalWrite(blue2, LOW);
  noTone(speaker);
}

Code Explanation:

• First, variables are declared.
• They store pin numbers for LEDs and speaker.
• Then setup function runs once.
• All LED pins are set as output.
• Speaker pin is also output.
• Serial communication starts for Bluetooth.
• Loop function runs again and again.
• Arduino checks if Bluetooth data is received.
• If data is received, it is stored.
• If command is “1” then police effect starts.
• LEDs blink like police lights.
• Speaker makes siren sound.
• If command is “0” then everything stops.
• LEDs turn OFF and speaker becomes silent.
• Police effect function controls blinking.
• Red LEDs ON first.
• Blue LEDs OFF.
• Then red OFF and blue ON.
• Tone function creates siren sound.
• Different tones make up-down sound.
• Stop function turns OFF all outputs.
• No sound is produced.
• Thus Bluetooth controls police siren and lights.

Circuit Working:

Parts List:

Components	Quantity
Resistor 220Ω 1/4 watt	4
Arduino UNO	1
Speaker 0.25 watt 8Ω	1
LED 5mm 20mA red color	2
LED 5mm 20mA blue color	2
Bluetooth Module HC-05 Serial	1
Android Device	1

First at start power is given to Arduino and then Bluetooth module turns ON.

After that mobile phone sends command and Bluetooth receives the signal and then it sends data to Arduino.

Arduino reads the data and if command is ON then LEDs start blinking.

Red and blue LEDs blink alternately and at the same time Arduino generates tone and speaker produces siren sound.

If OFF command is sent then everything stops and thus, police siren and lights are controlled wirelessly.

Formula with Calculation:

Formula for LED Resistor Calculation:

Supply Voltage = 5V
LED Forward Voltage = 2V
LED Current = 20mA (0.02A)

Resistor Value = (Supply Voltage – LED Voltage) / LED Current

Resistor Value = (5 – 2) / 0.02
Resistor Value = 3 / 0.02
Resistor Value = 150 ohm

Standard value resistor is used is 220 ohm which is safe for LED.

How to Build:

To build a Bluetooth Controlled Police Siren Sound Circuit with Arduino follow the below steps:

• First collect all components as per circuit diagram.
• Arduino digital pin 8 connects to first red LED using resistor.
• Digital pin 9 connects to second red LED using resistor.
• Digital pin 10 connects to first blue LED using resistor.
• Digital pin 11 connects to second blue LED using resistor.
• Digital pin 6 connects to speaker positive.
• All LEDs, speaker and Bluetooth negatives connect to GND.
• HC-05 VCC pin connects to Arduino 5V.
• HC-05 GND pin connects to Arduino GND.
• TXD pin connects to Arduino RX pin 0.
• RXD pin connects to Arduino TX pin 1.

Note:

Download the Android application from play store:

• Arduino Bluetooth Controller
• Bluetooth Terminal
• Bluetooth Electronics
• Serial Bluetooth Terminal

Connection:

• Install the app in Android mobile.
• Turn ON mobile Bluetooth.
• Connect Bluetooth to HC-05 module and enter password .
• Open the app and connect HC-05.
• Now test the police siren and lights.

Conclusion:

To conclude, this project for Bluetooth Controlled Police Siren Sound Circuit with Arduino is simple and useful.

It explains Arduino, Bluetooth and LED control.

Moreover, it helps beginners understand wireless communication.

Also it shows how sound and light can work together.

Therefore, Police Siren and Lights using Arduino is a good learning project.

References:

Police Siren Alarm