Turning Any R/C Car into a Bluetooth App Controlled Car

The are many lot cost RC cars with lots of features like the LED headlights and underglow lights. However, the remote controller came with the car cannot control lights and motors individually. With mobile App and Arduino board, we can convert these ordinary RC Cars to a more advanced bluetooth control toys.

We are using an Arduino Compatible board with BLE (Bluetooth Low Energy) by Wombatics, so that it works with both iOS and Android phone.

1. Picking a RC Car

We picked a Fast Lane 1:24 RC Car. This car is prefect for this project, as it has all features that we are looking for, such as headlight and underglow LEDs with enough room to put our board inside.

2. Taking the Car apart

After taking it apart, identify the wires for LEDs and motors. The desoldering them off the board and replace them with Arduino board and motor drive module.

3. Putting on the motor drive module

In this step, solder the steering motor to "MOTO A" and back motor to "MOTO B" on the motor driver module. Solder jumper wires to headlight & under-glow LEDs on both +ve & -ve side.

4. Connecting to the SAM01 Arduino robotics board

Putting on the SAM01 Arduino Robotics Board and connecting the jumper wires as following.

PIN 3 - INT1 for Motor A (Steering Motor)PIN 5 - INT2 for Motor A PIN 6 - INT3 for Motor B (Drive Motor)PIN 9 - INT4 for Motor BPIN 10 - Headlight LEDsPIN 13 - Under-glow LEDs

5. Arduino Coding & Testing

Now it is time for testing all the connections. I have made Sam_RC_Car_Test.ino for ease of testing. Upload the ino file with Arduino IDE.

** Set board to "Arduino Nano" in Arduino IDE**

/*************************************************************
 SAM01 RC Car Connections Testing
*************************************************************
 This example shows how to use SAM01 Arduino Robotics board
 to control a RC Car.
 This example code is in the public domain.
 https://github.com/wombatics/sam01/tree/master/Arduino/examples
*************************************************************/
#define MA1 3
#define MA2 5
#define MB1 6
#define MB2 9
#define BOTTOM_LED 13
#define FRONT_LED 10
void setup() {
 // put your setup code here, to run once:
 Serial.begin(9600);
 pinMode(MA1, OUTPUT);
 pinMode(MA2, OUTPUT);
 pinMode(MB1, OUTPUT);
 pinMode(MB2, OUTPUT);
 pinMode(BOTTOM_LED, OUTPUT);
 pinMode(FRONT_LED, OUTPUT);
}
void loop() {
 // right
 analogWrite(MA1, 255);
 analogWrite(MA2, 0);
 // forward
 analogWrite(MB1, 150);
 analogWrite(MB2, 0);
 delay(3000);
 // left
 analogWrite(MA1, 0);
 analogWrite(MA2, 255);
 // stop
 analogWrite(MB1, 0);
 analogWrite(MB2, 0);
 delay(3000);
 // middle
 analogWrite(MA1, 0);
 analogWrite(MA2, 0);
 // backward
 analogWrite(MB1, 0);
 analogWrite(MB2, 255);
 delay(3000);
 // Testing LEDs
 digitalWrite(BOTTOM_LED, HIGH);
 digitalWrite(FRONT_LED, HIGH);
 delay(100);
 digitalWrite(BOTTOM_LED, LOW);
 digitalWrite(FRONT_LED, LOW);
 delay(100);
} 

6. Prepare for Blynk

After the connections are verified. We are ready to connect with Blynk through BLE.

First upload the file Sam_Blynk_RC_Car.ino with Arduino IDE.

/*************************************************************
 SAM01 RC Car with Blynk.
 Blynk is a platform with iOS and Android apps to control
 Arduino, Raspberry Pi and the likes over the Internet / 
 WiFi / Bluetooth.
*************************************************************
 This example shows how to use SAM01 Arduino Robotics board
 to connect a RC Car to Blynk.
 NOTE: BLE support is in beta for Blynk. Too much data will
 cause errors in BLE with Blynk.
 This example code is in the public domain.
 https://github.com/wombatics/sam01/tree/master/Arduino/examples
*************************************************************/
#define MA1 3
#define MA2 5
#define MB1 6
#define MB2 9
#define BOTTOM_LED 13
#define FRONT_LED 10
//#define BLYNK_USE_DIRECT_CONNECT
// You could use a spare Hardware Serial on boards that have it (like Mega)
#include <SoftwareSerial.h>
SoftwareSerial BLESerial(10, 9); // RX, TX
#define BLYNK_PRINT Serial
#include <BlynkSimpleSerialBLE.h>
// You should get Auth Token in the Blynk App.
// Go to the Project Settings (nut icon).
char auth[] = "yourAuthToken";
bool turbo;
void forward(int speed)
{
 analogWrite(MB1, speed);
 analogWrite(MB2, 0);
// Serial.println("Speed: ");
// Serial.println(speed);
}
void backward(int speed)
{
 analogWrite(MB1, 0);
 analogWrite(MB2, -speed);
 // Serial.println("back speed: ");
 // Serial.println(speed);
}
void right(int speed)
{
 analogWrite(MA1, speed);
 analogWrite(MA2, 0);
}
void left(int speed)
{
 analogWrite(MA1, 0);
 analogWrite(MA2, speed);
}
BLYNK_WRITE(V0)
{
 int pinValue = param.asInt(); // assigning incoming value from pin V1 to a variable
 Serial.println(pinValue);
 if(pinValue >= 0)
 {
   if(turbo)
     forward(pinValue);
   else if (pinValue == 0)
     forward(0);
   else
     forward(pinValue * 0.7 + 30);
 }
 else
 {
   backward(pinValue * 0.7 - 30);
 }
}
BLYNK_WRITE(V2)
{
 int pinValue = param.asInt(); // assigning incoming value from pin V1 to a variable
 //Serial.print("Left ");
 //Serial.println(pinValue);
 if(pinValue)
   left(255);
 else
   left(0);
}
BLYNK_WRITE(V3)
{
 int pinValue = param.asInt(); // assigning incoming value from pin V1 to a variable
 //Serial.print("Right ");
 //Serial.println(pinValue);
 if(pinValue)
   right(255);
 else
   right(0);
} 
BLYNK_WRITE(V1)
{
 int pinValue = param.asInt(); // assigning incoming value from pin V1 to a variable
 if(pinValue)
   turbo = true;
 else
   turbo = false;
}
void setup()
{
 // Debug console
 Serial.begin(115200);
 Serial.println("Waiting for connections...");
 // Blynk will work through Serial
 // Do not read or write this serial manually in your sketch
 BLESerial.begin(9600);
 Blynk.begin(BLESerial, auth);
 pinMode(MA1, OUTPUT);
 pinMode(MA2, OUTPUT);
 pinMode(MB1, OUTPUT);
 pinMode(MB2, OUTPUT);
 forward(0);
 turbo = false;
}
void loop()
{
 Blynk.run();
} 

7. Setup Blynk

Copy the Auth Token back to Sam_Blynk_RC_Car.ino.

char auth[] = "yourAuthToken"; 

8. Final Step - Connect and Start Playing

Turn on the RC Car's power and search for SAM01 in Blynk App by following the steps below

9. Ready to GO!!