IR Distance Sensor With Cables Gp2y0a41sk0f 0a41sk 4-30cm

Working Principle

• The sensor emits infrared light using an IR-LED.
• When this light hits an object, it reflects back to the PSD.
• The PSD detects the reflected light, and the sensor outputs an analog voltage that corresponds to the distance of the object.
• The output voltage is inversely proportional to the distance, making closer objects produce higher voltages.

Features

• Accurate short-range distance measurement (4 to 30 cm)
• Analog voltage output
• Compact size and easy to integrate
• Low power consumption
• Uses a 3-pin JST PH connector

Wiring Connections

Sample Code

#define sensor A0  // Sharp IR GP2Y0A41SK0F (4-30cm, analog)

void setup() {
  Serial.begin(9600); // Start the serial port
}

void loop() {
  float volts = analogRead(sensor) * 0.0048828125; // Convert analog to voltage (5V / 1024)
  Serial.println(volts);

  int distance = 13 * pow(volts, -1); // Estimate distance from voltage
  delay(1000); // Delay for readability

  if (distance <= 30) {
    Serial.println(distance); // Print distance if within range
  }
}

Notes

• No external library is required to use this sensor.
• Ensure the sensor is connected to the correct analog pin on the Arduino.
• The formula 13 * pow(volts, -1) is derived from the datasheet curve of output voltage vs. distance.

Understanding the Output

• Why multiply by (5 / 1024)?
  Analog pins read a value from 0 to 1023 (10-bit ADC), corresponding to 0V to 5V. Multiplying by (5 / 1024) converts it to real voltage.
• What does pow(volts, -1) do?
  This calculates the reciprocal of the voltage to approximate the distance based on the sensor's nonlinear response curve.

Getting Started

1. Connect the Arduino to your PC using a USB cable.
2. Open the Arduino IDE (install from arduino.cc if needed).
3. Select the correct board from Tools > Board.
4. Select the correct COM port from Tools > Port.

Applications

• Proximity sensing
• Obstacle detection in robots
• Short-range object detection
• Interactive systems and smart devices