How To Use IR Sensor!

Learn To Operate IR Sensor With Arduino

Mariam Manzoor
DeepLift
3 min readNov 29, 2020

--

Thumbnail By DeepLift

Introduction

Arduino UNO is a microcontroller board- it is the brain of any electronics project. IR sensor, on the other hand, is an infrared rays transmitter and receiver. In the following project, we will learn the working principle of IR sensor followed by its application as a discriminator between black and white surfaces and as an obstacle detector with Arduino UNO.

IR Sensor

FC-51 IR Sensor emits and detected infrared radiations. IR radiations are part of the electromagnetic spectrum, with wavelength higher than that of visible light, and are generally invisible to the human eye.

The IR sensor consists of:

  1. IR Emitter LED: Emits infrared light
  2. IR Receiver: A photodiode with resistance depending on the amount of IR light falling on it
  3. Distance Adjuster: Changes detection distance
  4. Vcc Pin: Provides 3–5 V input voltage
  5. Gnd Pin: Ground input
  6. Out Pin: Transmits output signal from the sensor to Arduino
  7. Obstacle LED: Turns on when light falls on IR Receiver
  8. Power LED: Turns on when the sensor is connected to a voltage source
Photo from http://qqtrading.com.my

Working of IR Sensor:

Photo from https://osoyoo.com

As per the property of light — light falling on a smooth shiny surface bounces off in a particular direction i.e. reflection — the ray send by IR Transmitter gets reflected from a surface and falls on IR Reciever. Subsequently, the receiver’s resistance drops, and a LOW/0 signal is sent by the OUT pin to the microcontroller.

Photo by Mariam Manzoor — DeepLift

Similarly, when the light sent isn’t reflected either because there is no surface ahead or the surface ahead absorbs light, the resistance of the receiver rises and a HIGH/1 signal is sent by OUT pin to the microcontroller.

Photo by Mariam Manzoor — DeepLift

IR Sensor differentiating between black (rough) and white (smooth and reflective) surface

Photo by Mariam Manzoor — DeepLift

IR Sensor detecting an obstacle

Photo by Mariam Manzoor — DeepLift

Using IR Sensor with Arduino

Hardware requirements:

  1. Arduino UNO
  2. Arduino Cable
  3. LED
  4. IR Sensor
  5. Jumper Wires
  6. BreadBoard

Software Requirements:

  1. Arduino IDE
  2. Copy-paste the code from here:

Connections:

Photo by Mariam Manzoor — DeepLift

Connect Arduino to Laptop using USB cable, and upload the code. Open serial monitor to view results.

Sample Output

Conclusion

In the above mini-project, it was shown how the IR sensor can be used along Arduino to detect obstacles or differentiate between reflecting and non-reflecting surfaces. IR sensor, along with Arduino is used in many sensor-based electronic projects like line following car, obstacle avoiding car, and gesture control robot.

If you liked our effort consider subscribing to our Publication, and YouTube Channel.

--

--

Mariam Manzoor
DeepLift

Hey Friends! I’m Mariam, a Science and Technology Enthusiast and I’m here to share my Ideas and Explorations in the field of AI and Robotics.