This is our new Bluetooth RC car - based on our favorite Arduino UNO! In this project as you can see we used a custom-made PCB board and the ATmega328p micro controller. The board is specially design for this project and for small RC models. You can simple control it from your Android phone or tablet via Bluetooth. From the Android application you can also turn on/off the front and rear lights and play a horn sound! For our RC model we used only 3x1.5V AA batteries!

Project updates and more Arduino projects can be found here:

http://www.ardumotive.com/arduino-bluetooth-rc-car...

Here is a video from our RC car with assembly/soldering instructions!

Step 1: What You Will Need - Hardware

For this project you will need:

Our custom PCB circuit (find it in next step)
Atmega328 (with Arduino UNO bootloader)
28 pin dip socket & 2x 16 pin dip socket
2x L293 IC or SN754410
16 MHz crystal oscillator
10 uF capacitor
2x22 pF ceramic capacitors
10 kOhm resistor
Buzzer
Bluetooth module HC-06 (or HC-05)
4x screw terminal 2P 2.54mm
Pin header 1x5 Female
Pin header 1x40 Male

You will also need a TTL to USB module or an Arduino UNO board for the programming procedure.

Step 2: Circuit Schematic

Order it from pcbway.com and get 10pcs PCB for free! (only for new members)

Instructions on how to order it can be found in the video that we have in first step.

You can also make your changes here:

https://easyeda.com/mi.vasilakis/My_PCB-9fb30c4a0c...

Step 3: The Code

Connect your circuit with the TTL to USB module with 5 cables to the programming header or insert the atmega328 IC to your Arduino UNO board and upload the code! (after the programming procedure remove it and install it again to our custom pcb board).

/* Arduino Bluetooth Car<br> * Created by Vasilakis Michalis // updated: 31/7/2019
 * More information at www.ardumotive.com
 */
#include 
//Software serial connection for bt module
SoftwareSerial btSerial(A2,A3); // RX & TX

//L293 Connection   
const int motorA1  = 5;  // Pin  2 of L293
const int motorA2  = 3;  // Pin  7 of L293
const int motorB1  = 11; // Pin 10 of L293
const int motorB2  = 10;  // Pin 14 of L293
//Leds connected to Arduino UNO Pin 12
const int front_lights  = 8;
const int back_lights = 7;
//Buzzer / Speaker to Arduino UNO Pin 3
const int buzzer = 2 ;

//Useful Variables
int i=0;
int j=0;
char state;

void setup() {
  // Initialize serial communication at 9600 bits per second:
  btSerial.begin(9600);
  Serial.begin(9600); // Only for debugging
  // Set pins as outputs:
  pinMode(motorA1, OUTPUT);
  pinMode(motorA2, OUTPUT);
  pinMode(motorB1, OUTPUT);
  pinMode(motorB2, OUTPUT);
  pinMode(front_lights, OUTPUT);
  pinMode(back_lights, OUTPUT);
  delay(500);
  //Stop all motors
  digitalWrite(motorA1, LOW);
  digitalWrite(motorA2, LOW);
  digitalWrite(motorB1, LOW);
  digitalWrite(motorB2, LOW);
}
 
void loop() {
  //Save income data to variable 'state'
    if(btSerial.available() > 0){     
      state = btSerial.read(); 
      Serial.println(state);  
    }	  
  /***********************Forward****************************/
  //If state is equal with letter 'F', car will go forward!
    if (state == 'F') {
    	digitalWrite(motorA1, HIGH); digitalWrite(motorA2, 0);
      digitalWrite(motorB1, 0);      digitalWrite(motorB2, 0); 
      Serial.println("Moving Forward");
    }
  /**********************Forward Left************************/
  //If state is equal with letter 'G', car will go forward left
    else if (state == 'G') {
    	digitalWrite(motorA1, HIGH); digitalWrite(motorA2, 0);  
      digitalWrite(motorB1, HIGH);    digitalWrite(motorB2, 0);
      Serial.println("Moving Forward Left"); 
    }
  /**********************Forward Right************************/
  //If state is equal with letter 'I', car will go forward right
    else if (state == 'I') {
      digitalWrite(motorA1, HIGH); digitalWrite(motorA2, 0); 
      digitalWrite(motorB1, 0);      digitalWrite(motorB2, HIGH); 
      Serial.println("Moving Forward Right");
    }
  /***********************Backward****************************/
  //If state is equal with letter 'B', car will go backward
    else if (state == 'B') {
    	digitalWrite(motorA1, 0);   digitalWrite(motorA2, HIGH); 
      digitalWrite(motorB1, 0);   digitalWrite(motorB2, 0); 
      Serial.println("Moving Backward");
    }
  /**********************Backward Left************************/
  //If state is equal with letter 'H', car will go backward left
    else if (state == 'H') {
    	digitalWrite(motorA1, 0);   digitalWrite(motorA2, HIGH); 
      digitalWrite(motorB1, HIGH); digitalWrite(motorB2, 0);
      Serial.println("Moving Backward Left"); 
    }
  /**********************Backward Right************************/
  //If state is equal with letter 'J', car will go backward right
    else if (state == 'J') {
    	digitalWrite(motorA1, 0);   digitalWrite(motorA2, HIGH); 
      digitalWrite(motorB1, 0);   digitalWrite(motorB2, HIGH); 
      Serial.println("Moving Backward Right");
    }
  /***************************Left*****************************/
  //If state is equal with letter 'L', wheels will turn left
    else if (state == 'L') {
    	digitalWrite(motorA1, 0);   digitalWrite(motorA2, 0); 
      digitalWrite(motorB1, HIGH); digitalWrite(motorB2, 0); 
      Serial.println("Turn Left");
    }
  /***************************Right*****************************/
  //If state is equal with letter 'R', wheels will turn right
    else if (state == 'R') {
    	digitalWrite(motorA1, 0);   digitalWrite(motorA2, 0); 
      digitalWrite(motorB1, 0);   digitalWrite(motorB2, HIGH); 
      Serial.println("Turn Right");		
    }
  /************************Lights*****************************/
  //If state is equal with letter 'W/w', turn front leds on or of off
    else if (state == 'W') {
      digitalWrite(front_lights, HIGH); 
      Serial.println("Turning front lights ON");
    }
    else if (state == 'w') {
      digitalWrite(front_lights, LOW); 
      Serial.println("Turning front lights OFF");
    }
  /************************Lights*****************************/
  //If state is equal with letter 'U/u', turn back leds on or of off
    else if (state == 'U') {
      digitalWrite(back_lights, HIGH); 
      Serial.println("Turning rear lights ON");
    }
    else if (state == 'u') {
      digitalWrite(back_lights, LOW); 
      Serial.println("Turning rear lights OFF");
    }  
  /**********************Horn sound***************************/
  //If state is equal with letter 'V', play (or stop) horn sound
    else if (state == 'V'){
      tone(buzzer,500);
      Serial.println("Playing horn sound");
    }
    else if (state == 'v'){
      noTone(buzzer);
      Serial.println("Stop playing horn sound");
    }
  /************************Stop*****************************/
  //If state is equal with letter 'S', stop the car
    else if (state == 'S'){
        digitalWrite(motorA1, 0);  digitalWrite(motorA2, 0); 
        digitalWrite(motorB1, 0);  digitalWrite(motorB2, 0);
        Serial.println("STOP");
    }  
}