Home automation using relay

About This Project

Home automation using relay. For my robotics class graduation, I got the idea to do this.

Components Required

Arduino UNO
Power Relay, SPDT
PIR Motion Sensor (Generic)
Temperature Sensor
IR Receiver
6 Pin Gas Sensor
LED Light Bulb, Frosted GLS
DC Motor
Buzzer, Piezo
Resistor 10k ohm
9V battery
General Purpose Transistor NPN
1N4007 - High Voltage, High Current, Rated Diode
Resistor 1k ohm

Schematics

In this image all the components with the connections are given.

Code Of Project

// declare integer variables
int PIR = 0;
int temp = 0;
int IR = 0;
int gas = 0;

void setup() {
  // declare inputs
  pinMode(6, INPUT);
  pinMode(7, INPUT);
  pinMode(5, INPUT);
  pinMode(4, INPUT);
  // declare outputs
  pinMode(13, OUTPUT);
  pinMode(12, OUTPUT);
  pinMode(11, OUTPUT);
  pinMode(10, OUTPUT);
  // begin the serial port with a baud rate of 9600
  Serial.begin(9600);
}

void loop() {
  // declare variables
  PIR = digitalRead(4);
  temp = analogRead(5);
  IR = digitalRead(7);
  gas = analogRead(6);
  // if else statements
  if (temp >= 500) {
    digitalWrite(12, HIGH);
    Serial.println("fan on");
  } else {
    digitalWrite(12, LOW);
    Serial.println("fan off");
  }
  if (PIR == 1) {
    digitalWrite(13, HIGH);
    Serial.println("lights on");
  } else {
    digitalWrite(13, LOW);
    Serial.println("lights off");
  }
  if (gas >= 200) {
    digitalWrite(10, HIGH);
    Serial.println("gas leak");
  } else {
    digitalWrite(10, LOW);
  }
  if (IR == 1) {
    digitalWrite(11, HIGH);
    Serial.print("signal received");
  } else {
    digitalWrite(11, LOW);
  }
  delay(30); // delay 30 milliseconds to let things settle
}