IR sensor (with or without Arduino)

 IR Sensor without Arduino

Circuit Diagram: (LED and Relay):

Video:

IR sensor with Arduino

A servo motor is activated when any obstacle comes in front of IR sensor.

Circuit Diagram:

Arduino Code:

#include <Servo.h> 

Servo myservo; // create servo object to control a servo 

const int IRpin = 4;

void setup() { 

   myservo.attach(5); // pin 5 of Arduino with servo motor

   pinMode(IRpin, INPUT);

   myservo.write(0);

   delay(500);

   myservo.write(90);

}

void loop() { 

  if(digitalRead(IRpin)==0)

     myservo.write(0); // tell servo to go to a particular angle

  else

    myservo.write(90);

}

Video: