Published October 24, 2026 © LGPL

Automatic Touchless Tap with Arduino

A hygienic, water-saving tap that opens automatically when hands come within 15cm using HC-SR04 and servo.

BeginnerFull instructions provided2 hours4

Things used in this project

Hardware components

Arduino UNO

SG90 Micro-servo motor

SparkFun Electronics Ultrasonic Sensor - HC-SR04

Software apps and online services

Arduino IDE

Autodesk Tinkercad

Hand tools and fabrication machines

Soldering iron (generic)

Story

### Automatic Touchless Tap with Arduino**Problem:** Normal taps spread germs and waste water.**Solution:** This tap opens automatically when you bring your hand near it.**How it Works:**1. HC-SR04 sensor continuously measures distance.2. Arduino checks if distance is less than 15cm.3. If hand is detected, Arduino rotates Servo Motor to 90 degrees to open the tap.4. After 3 seconds, tap closes automatically.**Components Used:**- Arduino UNO- HC-SR04 Ultrasonic Sensor- Servo Motor SG90- Jumper Wires**Tinkercad Simulation Link:**https://www.tinkercad.com/things/2a92OdCjcOj/**Benefits:** 100% Hygienic, Saves Water, Low Cost.

Code

Arduino Code for Touchless Tap

#include <Servo.h>
Servo tapServo;
const int trigPin = 9;
const int echoPin = 10;
const int servoPin = 6;
long duration;
int distance;
void setup() {
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  tapServo.attach(servoPin);
  tapServo.write(0);
  Serial.begin(9600);
}
void loop() {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin, HIGH);
  distance = duration * 0.034 / 2;
  if (distance < 15) {
    tapServo.write(90);
    delay(3000);
  } else {
    tapServo.write(0);
  }
  delay(200);
}