Bluetooth Controlled Car with LED Indicators

Abstract

This research paper presents the design and implementation of a Bluetooth Controlled Car with LED Indicators. The system demonstrates wireless communication, motor control, and directional signaling using Arduino Uno, HC-05 Bluetooth module, and L298N motor driver. The addition of LED indicators provides real-time feedback, making it an educational and practical project for robotics learning. This paper outlines the system overview, setup, working principle, tools, and future scope.

System Overview

The Bluetooth Controlled Car with LED Indicators is a microcontroller-based robotic project designed to demonstrate wireless communication, motor control, and directional signaling. The system uses an Arduino Uno (or Nano), HC-05 Bluetooth module, and L298N motor driver for mobility, while directional LEDs are integrated to provide visual feedback during movement. This makes the project a complete package for robotics learning, research, and prototyping. In addition, the project introduces students to embedded systems, sensor-actuator integration, and real-time control. It also helps in understanding how wireless communication can be applied in robotics. In future extensions, the same concept can be scaled up to Bluetooth-controlled drones or multifunctional robots for advanced applications.

Setup and Operational Guide

Essential Components

1.Arduino Uno (or any compatible Arduino board)

2.DC Motors (4 motors for movement control)

3.Motor Driver (L298N or L293D)

4.LEDs (5 LEDs: 2 for Forward, 2 for Backward, and 1 for Blinking)

5.Resistors (for LEDs and other components as needed) 6.Jumper Wires (for connections)

7.Power Supply (for motors, Arduino, and other components)

8.Breadboard (for prototyping connections)

9.Bluetooth Module (HC-05 or HC-06 for remote control)

Wiring Setup (Basic)

1.Motor Driver VCC → 5V (or external power for motors)

2.Motor Driver GND → GND (Arduino ground)

3.Motor Driver 5V → 5V (Arduino power supply for logic)

Arduino to Motor Driver:
1.IN1 → D8

2.IN2 → D9

3.IN3 → D10

4. IN4 → D11,

5.ENA → Jumper (or D5 using PWM for speed control)

6.ENB → Jumper (or D6 using PWM for speed control)

HC-05 Bluetooth:
1.TX → RX

2.RX → TX

3.VCC → 5V

4. GND → GND

Forward LEDs:

ForwardLed1 → D8 ( Pin 8 on Arduino)

ForwardLed2 → D9 ( Pin 9 on Arduino)

Backward LEDs:

BackwardLed1 → D10 ( Pin 10 on Arduino)

BackwardLed2 → D11 ( Pin 11 on Arduino)

Blinking LED → D12 (Pin 12 on Arduino)

Circuit Diagram

char data; // Variable to store received data

// Define motor control pins

#define motorPin1 3

#define motorPin2 5

#define motorPin3 6

#define motorPin4 7

// Define LED pins

#define forwardLed1 8 // First LED for Forward

#define forwardLed2 9 // Second LED for Forward

#define backwardLed1 10 // First LED for Backward (Left-side)

#define backwardLed2 11 // Second LED for Backward (Right-side)

#define blinkLedPin 12 // Blinking LED

// Variables for blinking LED

unsigned long previousMillis = 0; // Stores the last time the LED was updated

const long blinkInterval = 0; // Blink interval in milliseconds (500ms = 0.5 seconds)

bool blinkLedState = LOW; // Current state of the blinking LED

void setup() {

Serial.begin(9600); // Start serial communication at 9600 baud rate

// Set motor control pins as output

pinMode(motorPin1, OUTPUT);

pinMode(motorPin2, OUTPUT);

pinMode(motorPin3, OUTPUT);

pinMode(motorPin4, OUTPUT);

// Set LED pins as output

pinMode(forwardLed1, OUTPUT);

pinMode(forwardLed2, OUTPUT);

pinMode(backwardLed1, OUTPUT);

pinMode(backwardLed2, OUTPUT);

pinMode(blinkLedPin, OUTPUT); // Set blinking LED pin as output

}

void loop() {

// Handle blinking LED

unsigned long currentMillis = millis(); // Get the current time

if (currentMillis - previousMillis >= blinkInterval) {

previousMillis = currentMillis; // Save the last time the LED was updated

blinkLedState = !blinkLedState; // Toggle the LED state

digitalWrite(blinkLedPin, blinkLedState); // Update the blinking LED

}

// Handle motor control and other LEDs

if (Serial.available() > 0) {

data = Serial.read(); // Read received data

// Control motor movement and LEDs based on received data

switch (data) {

case 'F': // Move Forward

digitalWrite(motorPin1, HIGH);

digitalWrite(motorPin2, LOW);

digitalWrite(motorPin3, HIGH);

digitalWrite(motorPin4, LOW);

// Turn on Forward LEDs

digitalWrite(forwardLed1, HIGH);

digitalWrite(forwardLed2, HIGH);

// Turn off Backward LEDs

digitalWrite(backwardLed1, LOW);

digitalWrite(backwardLed2, LOW);

break;

case 'B': // Move Backward

digitalWrite(motorPin1, LOW);

digitalWrite(motorPin2, HIGH);

digitalWrite(motorPin3, LOW);

digitalWrite(motorPin4, HIGH);

// Turn on Backward LEDs

digitalWrite(backwardLed1, HIGH);

digitalWrite(backwardLed2, HIGH);

// Turn off Forward LEDs

digitalWrite(forwardLed1, LOW);

digitalWrite(forwardLed2, LOW);

break;

case 'L': // Turn Left

digitalWrite(motorPin1, HIGH);

digitalWrite(motorPin2, LOW);

digitalWrite(motorPin3, LOW);

digitalWrite(motorPin4, LOW);

// Turn on Left-side Backward LED

digitalWrite(backwardLed1, HIGH);

digitalWrite(backwardLed2, LOW);

// Turn off Forward LEDs

digitalWrite(forwardLed1, LOW);

digitalWrite(forwardLed2, LOW);

break;

case 'R': // Turn Right

digitalWrite(motorPin1, LOW);

digitalWrite(motorPin2, LOW);

digitalWrite(motorPin3, HIGH);

digitalWrite(motorPin4, LOW);

// Turn on Right-side Backward LED

digitalWrite(backwardLed1, LOW);

digitalWrite(backwardLed2, HIGH);

// Turn off Forward LEDs

digitalWrite(forwardLed1, LOW);

digitalWrite(forwardLed2, LOW);

break;

case 'S': // Stop

digitalWrite(motorPin1, LOW);

digitalWrite(motorPin2, LOW);

digitalWrite(motorPin3, LOW);

digitalWrite(motorPin4, LOW);

// Turn off all directional LEDs

digitalWrite(forwardLed1, LOW);

digitalWrite(forwardLed2, LOW);

digitalWrite(backwardLed1, LOW);

digitalWrite(backwardLed2, LOW);

break;

}

Remote App

1.A smartphone app is used to send directional commands (forward, backward, left, right) through Bluetooth.

2.The HC-05 Bluetooth module receives these commands and transfers them to the Arduino via serial communication.

3.The Arduino processes and interprets the received commands.

4.Based on the instructions, Arduino sends appropriate signals to the L298N motor driver to control the DC motors.

5.At the same time, the Arduino activates the corresponding directional LEDs (front, back, left, or right) for visual feedback.

6.The DC motors then drive the car in the desired direction, while LEDs provide real-time indication of movement.

7.The system ensures smooth coordination between command input and physical response, reducing delays.

8.Directional LEDs make the system more user-friendly and safer, as movement can be tracked visually. This setup reflects real-world vehicle signaling concepts and helps learners understand embedded system integration.

Useful Tools

1.Arduino IDE (Coding & Uploading): Arduino IDE is used to write, compile, and upload the program into the Arduino board. It provides a simple platform for debugging and modifying the code easily.

2.MIT App Inventor / Bluetooth Controller App: MIT App Inventor or a ready-made Bluetooth controller app is used to design and send directional commands from a smartphone. This allows wireless communication between user and robot.

3.Multimeter (Testing Connections): A digital multimeter helps check voltage, continuity, and current flow in circuits. It is essential for troubleshooting wrong wiring or faulty components. 4.Soldering Kit (Permanent Wiring): A soldering iron and related tools are used to make permanent and stable connections. This ensures durability and reduces loose wiring issues in the project.

5.Simulation Tools (Proteus / Tinkercad): These tools allow testing and simulating the circuit and code virtually before implementing on hardware. It saves time, reduces error, and helps in better understanding of the system.

Features

1.Wireless Bluetooth Control

2. LED Indicators for Each Movement (Forward, Backward, Left, Right)

3.Efficient and Low Power Consumption

4.Rechargeable and Portable

5. Educational Value – Demonstrates robotics + embedded system integration

6.Future Expandable – Drone and Robot

Summary

The Bluetooth Controlled Car with LED Indicators is an educational yet practical robotics project. It combines wireless communication, motor driving, and LED-based feedback system in a simple but effective way. The integration of LEDs enhances user interaction by visually representing the car’s movement direction. Its modular nature allows future upgrades, such as developing a Bluetooth-controlled drone or a multi-functional robot, making it a foundation for more advanced research in robotics and IoT.

Bluetooth Controlled Car with LED Indicators

Abstract

System Overview

Setup and Operational Guide

Essential Components

Wiring Setup (Basic)

Circuit Diagram

Remote App

Useful Tools

1.Arduino IDE (Coding & Uploading): Arduino IDE is used to write, compile, and upload the program into the Arduino board. It provides a simple platform for debugging and modifying the code easily.

2.MIT App Inventor / Bluetooth Controller App: MIT App Inventor or a ready-made Bluetooth controller app is used to design and send directional commands from a smartphone. This allows wireless communication between user and robot.

5.Simulation Tools (Proteus / Tinkercad): These tools allow testing and simulating the circuit and code virtually before implementing on hardware. It saves time, reduces error, and helps in better understanding of the system.

Features

1.Wireless Bluetooth Control

2. LED Indicators for Each Movement (Forward, Backward, Left, Right)

3.Efficient and Low Power Consumption

4.Rechargeable and Portable

5. Educational Value – Demonstrates robotics + embedded system integration

6.Future Expandable – Drone and Robot

Summary

AUST Robotics Club

Robotics for Building a Safer Future