HC-SR04 Ultrasonic Sensor

Complete Guide: How to Use HC-SR04 Ultrasonic Sensor with Arduino | Stemvolt

Introduction

The HC-SR04 Ultrasonic Sensor is a simple yet powerful electronic sensor used for distance measurement. It is widely used in robotics, obstacle detection, and DIY electronics projects. In this guide, you will learn how to use HC-SR04 with Arduino, its working principle, wiring diagram, coding, and applications. At Stemvolt, we offer premium-quality HC-SR04 sensors with quick delivery across India.

What is HC-SR04 Ultrasonic Sensor?

The HC-SR04 Ultrasonic Sensor uses sonar technology to measure distance. It sends an ultrasonic pulse and calculates the time taken for the echo to return after bouncing off an obstacle. This time duration is converted into distance using Arduino.

Technical Specifications

Operating Voltage: 5V DC
Measuring Range: 2cm – 400cm (0.02m – 4m)
Accuracy: ±3mm
Frequency: 40kHz
Interface: 4 Pins (VCC, Trig, Echo, GND)
Compact Size, Lightweight and Durable

Components Required to Use HC-SR04 with Arduino

• Arduino UNO or compatible board
• HC-SR04 Ultrasonic Sensor Module
• Jumper Wires
• Breadboard (Optional)
• Power Supply (Battery or USB)

Wiring Diagram (Connection Guide)

VCC → 5V Arduino
GND → GND Arduino
Trig → Digital Pin (e.g., D9)
Echo → Digital Pin (e.g., D10)

Arduino Code for HC-SR04 Sensor

#define trigPin 9#define echoPin 10 void setup() {  Serial.begin(9600);  pinMode(trigPin, OUTPUT);  pinMode(echoPin, INPUT);} void loop() {  long duration, distance;  digitalWrite(trigPin, LOW);    delayMicroseconds(2);  digitalWrite(trigPin, HIGH);    delayMicroseconds(10);  digitalWrite(trigPin, LOW);    duration = pulseIn(echoPin, HIGH);  distance = (duration * 0.034) / 2;    Serial.print(“Distance: “);  Serial.print(distance);  Serial.println(” cm”);  delay(500);}

How HC-SR04 Works

Trigger Pin sends ultrasonic waves.
Echo Pin receives the reflected wave.
Arduino measures the time and converts it into distance using the formula:
Distance = (Time × Speed of Sound) / 2

Applications of HC-SR04 Ultrasonic Sensor

Obstacle Avoidance Robots
Distance Measurement Tools
Water Level Detection
Parking Assistance System
Smart Dustbins
DIY Arduino Projects and STEM Education Kits

Why Buy HC-SR04 Sensor from Stemvolt?

Trusted Quality Sensors
Budget-Friendly Prices
Same-Day Shipping Across India
Best for Schools, Colleges & Robotics Labs
STEM DIY Project Support