Home Automation using Arduino UNO and Android App

Home Automation using Arduino UNO and Android App

Home automation means automatic control of electrical and electronics appliances. It includes Lighting, switching and controlling appliances. In a home automation system we have a mobile host controller and a number of client module such as home appliances. These appliances are connected through relay, Bluetooth and micro controller.  The aim of this project is to control home appliances using a mobile host.

Components required 

Hardware

• Arduino UNO

• HC – 05 Bluetooth Module 

• 5 V Relay two channel

• Jumper/Connecting Wires

• Smart phone

• 5 V DC Adapter

Software

• Arduino IDE

• Android App

Warning: - AC is very risky and accidental shock could be fetal, so be sure to pursue appropriate safety precautions.  Predictable Designs assumes no accountability for any injury that may happen by following this tutorial.

Circuit and Working

The home automation circuit is built using Arduino Uno, Bluetooth and a 2-channel relay or as per the requirements. Using a 4-channel relay we can control only four loads.

The step-wise working is as follows:

      Step1: Upload the sketch in Arduino Uno. A Sample sketch is shown below: 

    

int relay1 = 10;
int relay2 = 11;

String readString;

void setup() {
  Serial.begin(9600);
  pinMode(relay1, OUTPUT);
  pinMode(relay2, OUTPUT);
 }

void loop() {
  while (Serial.available()) {
    delay(3);
    char c = Serial.read();
    readString += c;
  }
  if (readString.length() >0) {
    Serial.println(readString);
    if (readString == "1 ON")
    {
      digitalWrite(relay1, HIGH);
    }
    if (readString == "1 OFF")
    {
      digitalWrite(relay1, LOW);
    }
    //relay2
    if (readString == "2 ON")
    {
      digitalWrite(relay2, HIGH);
    }
    if (readString == "2 OFF")
    {
      digitalWrite(relay2, LOW);
    }

    //All on / off
    if (readString == "ALL ON")
    {
      digitalWrite(relay1, HIGH);
      digitalWrite(relay2, HIGH);
         }
    if (readString == "ALL OFF")
    {
      digitalWrite(relay1, LOW);
      digitalWrite(relay2, LOW);
    }
    //next
    readString="";
}
}

Step 2: Connect Relay with Arduino Uno

Relay      Adruino Uno

IN1      >   Pin 10
IN2      >   Pin 11

GND   >    GND

VCC   >     5V

Step 3: Connect Bluetooth Module with Arduino Uno 

Bluetooth  Module               Adruino Uno
RX                                   >        TX
TX                                   >        RX
GND                                >        GND
+5V                                >         3.3V

Step 4: Connect Relay and AC Load as shown below

Step 5: Power the Load and Adruino Uno ( use 5V Adapter)
Step 6: Install the Android App to control the appliances.