The Arduino-compatible Infrared Obstacle Avoidance module is widely used in robot obstacle avoidance and more. The sensor is comprised of an infrared transmitter/receiver pair emitting a certain IR frequency to detect obstacles with high precision. The detection range can be set between 2-40cm by adjusting the potentiometers, the detection angle is 35°.  The output port OUT sensor module can be directly connected to the microcontroller IO port which you can directly drive a 5V relay. This Infrared Obstacle Avoidance module operating voltage is 3-5V DC.

Test Code

int Led = 13; // define LED Interface
int buttonpin = 3; // define the obstacle avoidance sensor interface
int val; // define numeric variables val

void setup () {
pinMode(Led, OUTPUT); // define LED as output interface
pinMode(buttonpin, INPUT); // define the obstacle avoidance sensor output interface
}

void loop () {
val = digitalRead(buttonpin); // digital interface will be assigned a value of 3 to read val

// When the obstacle avoidance sensor detects a signal, LED flashes
if (val == HIGH) {
digitalWrite(Led, HIGH);
}
else {
digitalWrite(Led, LOW);
}
}