Published September 22, 2017 © GPL3+

Basic Ultrasonic Tutorial

A simple tutorial on getting readings from an ultrasonic sensor

BeginnerProtip18,568

Things used in this project

Hardware components

Arduino UNO

Ultrasonic Sensor - HC-SR04 (Generic)

Adafruit Standard LCD - 16x2 White on Blue

Resistor 220 ohm

Resistor 470 ohm

Breadboard (generic)

Jumper wires (generic)

Story

The desired readout

I am building an Arduino course for my students, and I could not find a tutorial on taking readings from an ultrasonic sensor. I wanted a simple tutorial which shows students how to get information from an ultrasonic sensor, and do something with it. So I decided to make one.

The project simply takes a reading from the ultrasonic sensor and then displays the measurement on a LCD. The code is very simple as its purpose is for explanation.

Code

Ultrasonic sensor introduction

#include <Ultrasonic.h>                   // import ultrasonic library
#include <LiquidCrystal.h>                // import LCD library

Ultrasonic ultrasonic(2,3);               // Register ultrasonic sensor with interface pins trig:2, echo:3
LiquidCrystal lcd(0,1,8,9,10,11);         // Register the LCD with interface pins RS:0, E:1, D4:8, D5:9, D6: 10, D7:11)

void setup() {
  // setup the LCD's number of coulumns and rows
  lcd.begin(16,2);
    
}

void loop() {
  // take a measurement and display it on the LCD
  lcd.clear();                            // Clears the screen in preparation of new measurement    
  lcd.print("Distance in cm:");           // Prints the first line of the display
  lcd.setCursor(0,1);                     // Moves cursor tot he second line of display
  lcd.print(ultrasonic.distanceRead());   // Takes measurement from US and prints it to LCD
  delay(500);                             // waits half a second

}