Ultrasonic Distance Sensor

En Ultrasonic distance sensor skickar ut korta ljudpulser och använder dem pulserna för att mäta avstånd. Ljudpulsen som skickas ut krockar med ett objekt och sen studsar tillbaka, så mäter den avståndet.

Såhär kan den se ut:

Kod från https://randomnerdtutorials.com/complete-guide-for-ultrasonic-sensor-hc-sr04/

/*
 * created by Rui Santos, https://randomnerdtutorials.com
 * 
 * Complete Guide for Ultrasonic Sensor HC-SR04
 *
    Ultrasonic sensor Pins:
        VCC: +5VDC
        Trig : Trigger (INPUT) - Pin11
        Echo: Echo (OUTPUT) - Pin 12
        GND: GND
 */
 
int trigPin = 11;    // Trigger
int echoPin = 12;    // Echo
long duration, cm, inches;
 
void setup() {
  //Serial Port begin
  Serial.begin (9600);
  //Define inputs and outputs
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
}
 
void loop() {
  // The sensor is triggered by a HIGH pulse of 10 or more microseconds.
  // Give a short LOW pulse beforehand to ensure a clean HIGH pulse:
  digitalWrite(trigPin, LOW);
  delayMicroseconds(5);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
 
  // Read the signal from the sensor: a HIGH pulse whose
  // duration is the time (in microseconds) from the sending
  // of the ping to the reception of its echo off of an object.
  pinMode(echoPin, INPUT);
  duration = pulseIn(echoPin, HIGH);
 
  // Convert the time into a distance
  cm = (duration/2) / 29.1;     // Divide by 29.1 or multiply by 0.0343
  inches = (duration/2) / 74;   // Divide by 74 or multiply by 0.0135
  
  Serial.print(inches);
  Serial.print("in, ");
  Serial.print(cm);
  Serial.print("cm");
  Serial.println();
  
  delay(250);
}

Källor:

https://www.sensorgruppen.se/produkter/sensor/ultraljud/