Ultrasonic Sensor Project with Arduino for Kids

Overview

This project tells about how to use an Ultrasonic sensor to print the object’s distance on the serial monitor.

This object’s distance is calculated and printed on a serial monitor in cm.

Hardware required 

1. Arduino Uno R3
2. LED
3. Resistor
4. Jumper Wires
5. Ultrasonic Sensor

Schematic Diagram

Fig 1.  Circuit Diagram

Arduino Code : 

#define echoPin 2 
#define trigPin 3 

long duration; // variable for the duration of sound wave travel
int distance; // variable for the distance measurement

void setup() {
  pinMode(trigPin, OUTPUT); 
  pinMode(echoPin, INPUT); 
  Serial.begin(9600); 
  Serial.println("Ultrasonic Sensor HC-SR04 Test"); 
  Serial.println("with Arduino UNO R3");
}

void loop() {
  // Clears the trigPin condition
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  // Sets the trigPin HIGH (ACTIVE) for 10 microseconds
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  // Reads the echoPin, returns the sound wave travel time in microseconds
  duration = pulseIn(echoPin, HIGH);
  // Calculating the distance
  distance = duration * 0.034 / 2; // Speed of sound wave divided by 2 (go and back)
  // Displays the distance on the Serial Monitor
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");
}

Precautions

1. Connections should be done properly.
2. Arduino is case Sensitive so code accordingly.
3. Give different and appropriate colors to the wires.
4. Use resistors for sensors and LED.