how to Light control using ultrasonic sensor and relay module

Hey guys,welcome to our site, in video i would like to show you a project about home automation.

this project is very use for our houses and offices, because when will enter the room automatically light will turn on and when went out from room automatically light will trun off. I will all requirements for this project, no need to worry about it, i will give you only the CODE beacuse you no  need the circuit, all pin are in circuit.Still if you having any doubt about the project, contact me.

const int trigPin = 2; const int echoPin = 3; const int relay = 10; long duration; int distance; int safetyDistance; void setup() { // put your setup code here, to run once: pinMode(trigPin, OUTPUT); // Sets the trigPin as an Output pinMode(echoPin, INPUT); pinMode(relay, OUTPUT);// Sets the echoPin as an Input Serial.begin(9600); // Starts the serial communication } void loop() { // put your main code here, to run repeatedly: // Sets the trigPin on HIGH state for 10 micro seconds digitalWrite(trigPin, LOW); delayMicroseconds(2); digitalWrite(trigPin, HIGH); delayMicroseconds(10); digitalWrite(trigPin,LOW); // Reads the echoPin, returns the sound wave travel time in microseconds duration = pulseIn(echoPin,HIGH); // Calculating the distance distance= duration*0.034/2; Serial.println(distance); delay(50); safetyDistance = distance; if((distance>=15)) { digitalWrite(relay, HIGH); } else if(distance<15) { digitalWrite(relay, LOW); } }