Published November 11, 2021

Smart Extension Board

Arduino based Smart Bluetooth Controlled Extension Board

IntermediateFull instructions provided2 hours942

Things used in this project

Hardware components

Arduino Nano R3

HC-05 Bluetooth Module

1N4007 – High Voltage, High Current Rated Diode

Resistor 220 ohm

Female Header 8 Position 1 Row (0.1")

General Purpose Transistor NPN

bc547

JLCPCB's Customized PCB

Software apps and online services

Arduino IDE

Arduino Bluetooth Controller

Story

Smart Extension Board

A home automation system typically connects controlled devices to a central smart home hub. The user interface for control of the system uses a mobile phone application. Bluetooth Controlled Electronic Home Appliances is a simple project, where we can control different electrical appliances and electronic devices using an Android device with the help of Bluetooth Technology
By following this guide, you will be able to know and make your smart extension board. This project guide contains the files necessary to help you step by step produce your own Smart Extension Board. Please follow the steps of the project to get a positive result.
Users should install an Android application in the user’s mobile to control the electrical loads. Using this Android application users can send the commands to the Bluetooth module to control the electrical loads. Bluetooth is used in this project... It can also be called a “Smart Extension Board” or “Android-based Home Automation System".

Step 1: Get your PCB ready!

Talking About Electronics

After making the circuit diagram I transformed it into a PCB design to produce it, to produce the PCB, I have chosen JLCPCB the best PCB supplier and the cheapest PCB provider to order my circuit. with the reliable platform, all I need to do is some simple clicks to upload the Gerber file and set some parameters like the PCB thickness color and quantity. I’ve paid just 2 Dollars to get my PCB after five days only, what I have noticed about JLCPCB this time is the "out-of-charge PCB color" which means you will pay only 2 USD for any PCB color you choose.

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As you can see in the pictures above the PCB is very well manufactured and I’ve got the same PCB design that we’ve made for our main board and all the labels and logos are there to guide me during the soldering steps. You can also download the Gerber file for this circuit from the download link below in case you want to place an order for the same circuit design.

Step 2: Get all the Components Listed below images.

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Step 3: Place all the components on PCB and solder it properly.

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Step 4: After soldering all the components to PCB, connect Arduino nano to your PC(use Arduino IDE) / Phone(use ArduinoDroid) and upload the code.

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Step 5: Download Arduino Bluetooth Controller from Play Store.

Turn ON the Bluetooth, pair the HC-05 Bluetooth module to the phone(usually the password is "1234" for the HC-05 Bluetooth module).
After pairing the Bluetooth module open the Arduino Bluetooth control app and connect HC-05.
Tap on the button icon, then tap on Button 1 and change the button name and ("ON"-"OFF")Command as shown in the images below.

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Step 6:

Connect both wires of Switch 1 of the Extension board to the screw terminal of Relay 1 on the PCB.
Do the same connection for Switch 2, 3 & 4 (i.e. Connect both wires of Switch 2,3 & 4 to the screw terminal of Relay 2,3 & 4 respectively on the PCB )
Make sure to connect the power cable for Arduino before closing the extension board.
Close the cover of the extension board and done!

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Final step:

Power the Arduino with any adapter or power bank, also power the extension board.
Connect the HC-05 with the Arduino Bluetooth control app and now turn on the electrical appliance with the help of the app wirelessly or even from the Physical Switch itself!

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New users will also get a $30 coupon while registering at JLCPCB via this blue link.

Thank you for reading this guide, hopefully, this guide provides full steps to help you to create your own SmartExtention Board. If you have any questions please post them in the comment section below.

Code

Untitled file

/*
 * Connections of Arduino and Bluetooth Module HC-05 for this Code:
 *      Arduino  |  Bluetooth Module (HC-05)
 *            1  |  RX
 *            0  |  TX
 *           3V  |  3V
 *          GND  |  GND
 */
//Ashu MHR Technical
// https://www.youtube.com/watch?v=Txb-9gg6uLo
// https://www.youtube.com/c/ashumhrtechnical
//Home Automation
/* Code starts from here */
String voice;
#define relay1 2    //Connect relay1 to pin 2
#define relay2 3    //Connect relay2 to pin 3
#define relay3 4   //Connect relay1 to pin 2
#define relay4 5    //Connect relay2 to pin 3
void setup()
{
  Serial.begin(9600);            //Set rate for communicating with phone
  pinMode(relay1, OUTPUT);       //Set relay1 as an output
  pinMode(relay2, OUTPUT);
  pinMode(relay3, OUTPUT);      //Set relay2 as an output
  pinMode(relay4, OUTPUT);
  digitalWrite(relay1, LOW);     //Switch relay1 off
  digitalWrite(relay2, LOW);     //Swtich relay2 off
  digitalWrite(relay3, LOW);     //Switch relay1 off
  digitalWrite(relay4, LOW);     //Swtich relay2 off
}
void loop()
{
  while(Serial.available())    //Check if there are available bytes to read
  {
    delay(10);                 //Delay to make it stable
    char c = Serial.read();    //Conduct a serial read
    if (c == '#'){
      break;                   //Stop the loop once # is detected after a word
    }
    voice += c;                //Means voice = voice + c
  }
    if (voice.length() >0)
    {
      Serial.println(voice);
      if(voice == "*switch on"){
        switchon();
      }               
      else if(voice == "*switch off"){
        switchoff();
      }             
      else if(voice == "bulb off"){   
        digitalWrite(relay1, LOW);
      }
      else if(voice == "bulb on"){
        digitalWrite(relay1, HIGH);
      }
       else if(voice == "bulb2 off"){   
        digitalWrite(relay2, LOW);
      }
      else if(voice == "bulb2 on"){
        digitalWrite(relay2, HIGH);
      }
       else if(voice == "fan off"){   
        digitalWrite(relay3, LOW);
      }
      else if(voice == "fan on"){
        digitalWrite(relay3, HIGH);
      }
      else if(voice == "fan2 off"){
        digitalWrite(relay4, LOW);
      }
      else if(voice == "fan2 on"){
        digitalWrite(relay4, HIGH);
      }
      voice="";
    }
}
void switchon()               //Function for turning on relays
{
  digitalWrite(relay1, LOW);
  digitalWrite(relay2, LOW);
  digitalWrite(relay3, LOW);
  digitalWrite(relay4, LOW);
}
void switchoff()              //Function for turning on relays
{
  digitalWrite(relay1, HIGH);
  digitalWrite(relay2, HIGH);
  digitalWrite(relay3, HIGH);
  digitalWrite(relay4, HIGH);
}

Credits

Ashu Mhr Technical

13 projects • 2 followers

Smart Extension Board

Things used in this project

Hardware components

Software apps and online services

Story

Step 1: Get your PCB ready!

Talking About Electronics

Schematics

PCB Gerber File

Code

Untitled file

Credits

Ashu Mhr Technical

Comments

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Smart Extension Board

Smart Extension Board

Things used in this project

Hardware components

Software apps and online services

Story

Step 1: Get your PCB ready!

Talking About Electronics

Related Download Files

Schematics

PCB Gerber File

Code

Untitled file

Credits

Ashu Mhr Technical

Comments

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