Project 8: IR Infrared Obstacle Avoidance Sensor

Introduction

The IR Infrared Obstacle Avoidance Sensor detects obstacles by emitting infrared light and measuring the reflected signal.
It provides a digital output (HIGH or LOW) depending on whether an object is detected.
The ESP32 can read the sensor’s output and take appropriate action, such as stopping or turning a motor.
In this tutorial, we’ll interface the IR sensor with the ESP32 to detect obstacles.

Required Components

• ESP32 Dev Board
• IR Sensor
• Jumper wires
• Breadboard (optional)

Pinout

Circuit Diagram / Wiring

• IR SENSOR VCC → VIN, 3.3V (ESP32)
• IR SENSOR GND → GND (ESP32)
• IR SENSOR OUT → GPIO 15 (ESP32)

Code / Programming

#define IR_SENSOR_PIN 15    // Define IR sensor pin

void setup() {
  Serial.begin(115200);      // Start serial communication
  pinMode(IR_SENSOR_PIN, INPUT);  // Set IR sensor pin as input
}

void loop() {
  int sensorValue = digitalRead(IR_SENSOR_PIN);   // Read the sensor value

  if (sensorValue == HIGH) {  // If no obstacle is detected
    Serial.println("No Obstacle");
  } else {  // If an obstacle is detected
    Serial.println("Obstacle Detected");
  }
  
  delay(500);  // Wait for half a second before next reading
}

Explanation

• The IR_SENSOR_PIN reads a digital HIGH or LOW value depending on obstacle detection.
• If the value is HIGH, no obstacle is detected; if LOW, an obstacle is present.
• The sensor value is printed to the Serial Monitor for feedback.

Testing and Troubleshooting

• Ensure that the sensor is powered correctly (VCC to 5V and GND to GND) and that the output pin is connected to the ESP32.
• If the sensor continuously reads “Obstacle Detected,” check if the sensor is too close to a surface or incorrectly calibrated.
• If no readings are displayed, ensure the sensor’s wiring is secure and the ESP32’s GPIO is set to INPUT.