Interfacing IR Sensor with Arduino

IR (Infrared) Sensor

An IR sensor uses infrared light to detect objects and measure proximity. It consists of an IR LED and a photodiode that detects reflected light. This module is widely used in obstacle detection, line-following robots, and motion sensing applications.

Arrangement

1. VCC
2. GND
3. OUT (Digital Output)

Types of IR Sensors

Analog IR Sensor

  • Provides variable voltage output based on distance.
  • Suitable for proximity detection and distance measurement.

Digital IR Sensor

  • Outputs HIGH/LOW based on object detection.
  • Used in obstacle detection and line-following robots.

Circuit Connections

Pin Configuration of IR Sensor

Standard IR Sensor Configuration

  • VCC: Connect to 5V on Arduino.
  • GND: Connect to Arduino ground (GND).
  • OUT: Connect to a digital input pin on Arduino.

Analog IR Sensor Configuration

  • Connect OUT pin to an analog input (e.g., A0).
  • Read varying voltage for distance measurement.

How Does an IR Sensor Work

An IR sensor emits infrared light, which reflects off objects. The reflected light is detected by a photodiode, which converts it to an electrical signal. Digital IR sensors provide a HIGH signal when an object is detected, while analog IR sensors output variable voltage depending on the object's distance.

Applications of IR Sensors

Algorithm

  1. Define the Pins

    • Assign the IR sensor OUT pin to a digital pin (e.g., pin 7).

  2. Initialize the Arduino

    • Set the IR sensor pin as INPUT in setup().
    • Begin serial communication for monitoring.

  3. Read IR Sensor Data

    • Check if the sensor outputs HIGH or LOW.
    • If HIGH, an object is detected.

  4. Trigger an Action

    • Perform actions like turning on LEDs when an object is detected.

  5. Repeat the Process

    • Continuously check the sensor and update actions.
1// Interfacing IR Sensor with Arduino for Object Detection
2
3// Define the pin connected to the OUT pin of IR sensor
4#define IR_SENSOR_PIN 2  // Digital Pin 2
5
6void setup() {
7  // Start the Serial Monitor at 9600 baud rate
8  Serial.begin(9600);
9
10  // Set the IR sensor pin as input
11  pinMode(IR_SENSOR_PIN, INPUT);
12}
13
14void loop() {
15  // Read the state of IR sensor
16  int sensorValue = digitalRead(IR_SENSOR_PIN);
17
18  // If sensorValue is LOW, an object is detected (for most IR sensors)
19  if (sensorValue == LOW) {
20    Serial.println("Object Detected");
21  } else {
22    Serial.println("No Object");
23  }
24
25  delay(500); // Delay to make output readable
26}
27

Components Required

  • Obstacle Detection in Robots
  • Line-Following Robots
  • Motion Detection Systems
  • Automatic Door Systems
  • Proximity Measurement

Conclusion

Interfacing an IR sensor with Arduino allows you to detect objects and measure proximity. This setup is widely used in automation and robotics, providing a simple and effective solution for motion and obstacle detection.