Introduction: Simple Project With the Ultrasonic Sensor (HC-SR04) +LED -Arduino Tutoriel-

Ultrasonic ranging module HC - SR04 provides 2cm - 400cm non-contact measurement function, the ranging accuracy can reach to 3mm. The modules includes ultrasonic transmitters, receiver and control circuit.

This is a simple example of using the ultrasonic sensor (HC-SR04) in Arduino where we will turn on a led with the variation of distance and print the distance from an object to the serial monitor.

Step 1: All the Necessary Components

1. Arduino Uno

2. Ultrasonic Sensor (HC-SR04).

3. Mini-BreadBoard

4. 1 kohm Resistor.

5. Jumpers.

6. Blue LED.

Step 2: Connect the Components

The connection of the components is very easy it is only necessary to follow the following pictures.

Step 3: Write Your Code

#define trigPin 13

#define echoPin 12

#define led 11

void setup()

{ Serial.begin (9600);

pinMode(trigPin, OUTPUT);

pinMode(echoPin, INPUT);

pinMode(led, OUTPUT);


void loop()

{ long duration, distance;

digitalWrite(trigPin, LOW);


digitalWrite(trigPin, HIGH);


digitalWrite(trigPin, LOW);

duration = pulseIn(echoPin, HIGH);

distance = (duration/2) / 29.1;

if (distance < 10)

{ digitalWrite(led,HIGH);


else {




Serial.println(" cm");



Step 4: Upload and Run .

You can change the value of distance by replacing 10 in the condition if (distance <=10) by the desired value.

LED Contest 2017

Participated in the
LED Contest 2017

Arduino Contest 2017

Participated in the
Arduino Contest 2017