Introduction: DIY Smartphone Controlled Bluetooth Car Using Arduino

About: Founder of letsmakeprojects.com...Sciency Guy who always try to make innovative projects,check out what i made in my instructable..

Hey guys in this instructable i will show you how you can make this Smartphone Controlled Bluetooth car using Arduino in an very easy way, RC car was one of the most enjoyable gadget in our younger days!

Now since we grew up it is better if we upgrade our gadgets accordingly, i would say this is not like the normal rc car. This car is completely programmable and there is no limitation to the creative touch which you can add to this.

I will be using the most simple materials available to build this robotic car but i have also kept the performance in mind.

With all these factors i have made a detailed instructable on making this, By building this you not only have the robotic car that can do small stunts but also get a chance to learn most of the things which you will need to make bigger projects in the future.

Now some explanation of this Robot car

This is controlled with your smartphone and there will be an app accordingly you can have the control panel, There are multiple apps on the store that you can use to run this car.

You can explore various options, the communication medium between the phone and the car is the Bluetooth and as we all know this tiny little car can work without any issues with the hardware we are using and the Bluetooth signals.

I have given all the information to build this including circuit diagram and codes along with a video tutorial of this project given in the below steps.


Supplies

Here are the components which you will need to build this project

Arduino Nano from here

HC-05 Bluetooth module

Small Breadboard

L298n Motor Driver

Jumper cables

Lithium ion battery

Battery Case

Bo motor and Wheels

Wheels

Small steel wire

Hot glue

Piece of hard cardboard

Star head screwdriver

Mobile phone with internet and Bluetooth

Arduino IDE

USB programming Cable

Step 1: Circuit Diagram and Codes

To make the circuit understandable for everyone i will break the explanation component wise

L298N Motor Driver Connections

12V pin to positive terminal of battery and 5v to Arduino nano Vin pin

GND pin on L298N to negative terminal of battery and Arduino ground.

IN1 to digital pin D3 on Arduino

IN2 to another digital D4 pin on Arduino

IN3 to another digital pin 7 on Arduino

IN4 to another digital pin 8 on Arduino

Speed control (PWM)

ENA to D5 pin on Arduino and ENB to another D6 pin on Arduino.

Arduino Nano Connections

Vin pin to positive terminal of the battery and GND pin to the negative terminal of the battery.

Control signals to L298N

Bluetooth Module (HC-05)

VCC to the 5V pin on Arduino and GND to the GND pin on Arduino.

TX to RX on Arduino and RX from module to TX on Arduino nano

BO Motor Connections

Motor 1 is Connected to OUT1 and OUT2 terminals on L298N Driver.

Motor 2 is Connected to OUT3 and OUT4 terminals on L298N.

After these connections are complete you can upload the code to the nano, You can also preupload the code before making the connections.

Copy and paste the below code in your arduino IDE, Check for proper port number and click on upload.

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Step 2: Making the Car Frame

There are plenty of readily available frames for this robotic car on the online and offline platforms, I would suggest you to build one by yourself.

I have made the frame for this car by my own and i will show you how i did that.

I have marked the size of my wheels and slightly increased the size so that there will be no obstruction in the movement, I will be using 3 wheels so for the rear wheel i will use regular robot car wheel.

The driving wheels are powered by BO motor and i will stick to the frame using hot glue, Apply hot glue and place the Bo motor and press it firmly for some time until the glue is dry.

Now place the circuit and using double sided adhesive or hot glue stick to the frame

Step 3: The Rear Wheel

I want to make the project simple considering the materials and the expenses, Using 4 powered wheels does not make any great difference in the overall working of the car so i decided to use only 3 wheels.

The rear wheel was kept in the middle of the frame so that it matches the alignment, The purpose of this wheel is to follow the direction of the front wheels.

The front wheels are driven by bo motor and the rear one simply follows the front wheel, I made a slot on the centre of the frame to fit this.

Now for the shaft i will use piece of filament alternatively you can use toothpick or a steel shaft.

Follow my method to connect this wheel to the frame, add hot glue to the sides and allow to dry completely.

Step 4: Finishing

I would suggest to attach the wheels in the end on any of the robotic car project you make since it avoids many messy situations like the wheel obstructing the work flow.

Add the motor driver to frame and connect the wires of the motor to the motor output pins and using a screwdriver tight the slots.

In the end connect the battery, You can use other type of batteries also, I found that 18650 battery gives great backup for such projects.

To be able to control the power supply i preadded the switch to the battery case, so that i can power on and off the supply to the board

Step 5: How to Use

Using this car is very simple, Almost it is similar to plug and play but with few extra steps

Power on the car first and wait for the hc05 module to blink, Now turn on the Bluetooth on your phone and check for HC05 name

Click on connect and now open the controller app on your phone, now the app will ask to click to connect, Click on that and now your car is connected to the phone and ready to use.

Explore various functions and there are also option to add led lights for the car, if you want a project of that let me know i will make a instructables on it too, That is all for this robot car, Thank you for reading

Step 6: Working Video

watch this video for the complete building of this car, If you have any questions on the circuit connections part then this video will have all the answers for your questions.

Feel free to customise this model and if you have any interesting tips for me let me know in the comments box.