3-IN-1 Robotic Car with Arduino Nano

Introduction

About this project

My first Arduino project. This is a four-wheel car with 3 modes:

• Auto: Obstacle avoiding
• Manual: Bluetooth controlling
• Manual: Infrared controlling

Unlike many tutorials on the internet, I build my robot to stop automatically without having to press any stop button. If I want the robot to run, I'll just hold the button on the controller and release it when i don't want to. Therefore, the robot become easier to control o.<

DEMO

Obstacle Avoiding

Bluetooth Controlling

IR Controlling

Components and Supplies

Image	Name	QTY
	Arduino Nano	1
	L298N - Motor Driver	1
	3-6V DC motor and wheel	4
	SG90 - Micro Servo Motor	1
	HC-SR04 - Ultrasonic Sensor	1
	HC-06 - Bluetooth module	1
	KY-022 - IR Receiver Sensor	1
	Mini breadboard	1
	Plastic box	1

Necessary tools

Image	Name
	Kid's engineering kit
	Soldering iron
	Hot glue gun
	Jumper wires
	Infrared remote control

Notes:

• I only use the short L-shape bracket in the engineering kit. You can buy a mounting bracket for ultrasonic sensor, which is way better :3
• You can use any IR remote, just make sure to edit the buttons' hex value in the code before uploading it to Arduino. I use the remote shown above and its hex codes are:

#define ON    0xFFA25D
#define OFF   0xFFE21D
#define MODE1 0xFFE01F
#define MODE2 0xFFA857
#define MODE3 0xFF906F
#define SOS   0xFF18E7
#define HOLD  0xFFFFFFFF // Generally, remote will send this value when you're holding a button

How to exactly know the hex codes?

Connect IR receiver module with Arduino like this

Then plug in the USB cable to upload the code.

#include <IRremote.h>

#define RECV_PIN 2 // Specifying the pin connected to receiver module
IRrecv irrecv(RECV_PIN);
decode_results button;

void setup(){
  Serial.begin(9600);
  irrecv.enableIRIn(); // Initialization to receive IR signals 
}

void loop(){
  if(irrecv.decode(&button)){ // Store decoded signal in `button`, return 0 if nothing is received        
    Serial.println(button.value); // Print the value to the serial monitor
    irrecv.resume();
  }
}

On Arduino IDE, go to Tools -> Serial Monitor (or press Ctrl+Shift+M) then press the buttons on the remote respectively to get their Hex values on the monitor.

App

• Arduino IDE

• Any Arduino bluetooth controller app.

  I chose Arduino Bluetooth Controlled Joystick. Besides two joystick modes and one accelerometer mode, this app provides Button Mode - the mode i'm using in this project. I use the default setting in the app:

  Button	Symbol	Character send
  Up arrow	˄	N
  Down arrow	˅	S
  Left arrow	˂	W
  Right arrow	˃	E
  Cross	X	1
  Circle	O	2
  Triangle	Δ	3
  Square	□	4

Schematic