if (sensorState == LOW) // Object detected digitalWrite(ledPin, HIGH); Serial.println("Object Detected!"); else // No object digitalWrite(ledPin, LOW);
Introduction In the world of embedded systems and robotics, few components are as ubiquitous or as essential as the infrared proximity sensor. Among the myriad of options available, the FC-51 IR Sensor stands out as a favorite for hobbyists and professionals alike. It is cheap, reliable, easy to interface with microcontrollers like Arduino, Raspberry Pi, and ESP32, and incredibly effective for non-contact object detection. Fc 51 Ir Sensor Datasheet
Keep ambient IR low, adjust the potentiometer for your target reflectivity, and always confirm the pinout before powering up. Keep ambient IR low, adjust the potentiometer for
| Feature | FC-51 | HC-SR04 (Ultrasonic) | TCRT5000 (Reflective) | | :--- | :--- | :--- | :--- | | | IR reflection | Sound wave echo | IR reflection | | Output | Digital (HIGH/LOW) | Analog (PWM width) | Analog/Digital (with add-on) | | Max Range | ~30 cm | ~400 cm | ~10 cm | | Color Sensitive? | Yes (dark objects reduce range) | No | Yes | | Cost | Very low ($1-2) | Low ($2-4) | Very low ($0.5-1) | | Best Use | Proximity switch, line follow (short range) | Distance measurement | Line following (very short) | int ledPin = 13
Happy sensing! Disclaimer: Specifications may vary slightly between manufacturers. Always test your specific module with a multimeter before integrating into a final design.
int sensorPin = 2; int ledPin = 13; int sensorState = 0; void setup() pinMode(sensorPin, INPUT); pinMode(ledPin, OUTPUT); Serial.begin(9600);