Project: Automatic Alcohol Dispenser

Jun 2, 2020 · 2 min read · Arduino uno corona virus covid19 hc-sr04 mg996r pandemic servo motor ultrasonic sensor ·

Introduction

This is my own version of automatic (No touch / touchless) alcohol / sanitizer dispenser. This is especially useful during this COVID19 pandemic. In here, we will be using an ultrasonic sensor to detect the presence of hand near the dispenser. When the ultrasonic sensor detects an object less than the set distance, it will rotate the attached servo motors to push the plunger of the dispenser.

Bill Of Materials

Arduino Uno
HC-SR04 ultrasonic sensor
MG996R servo motor
Some wires, dispenser, some piece of wood.

Video Demonstration

Source Code

 1#include "Servo.h"
 2
 3#define ECHO_PIN 6
 4#define TRIG_PIN 7
 5#define SERVO_PIN 9
 6
 7Servo myservo; // create servo object to control a servo
 8long duration, cm;
 9
10void setup() {
11  // put your setup code here, to run once:
12  Serial.begin (9600);
13  pinMode(ECHO_PIN, INPUT);
14  pinMode(TRIG_PIN, OUTPUT);
15  myservo.attach(SERVO_PIN); // attaches the servo on pin 9 to the servo object
16  myservo.write(60);
17  delay(1000);
18  Serial.println("SETUP Complete");
19}
20
21void loop() {
22  // The sensor is triggered by a HIGH pulse of 10 or more microseconds.
23  // Give a short LOW pulse beforehand to ensure a clean HIGH pulse:
24  digitalWrite(TRIG_PIN, LOW);
25  delayMicroseconds(5);
26  digitalWrite(TRIG_PIN, HIGH);
27  delayMicroseconds(10);
28  digitalWrite(TRIG_PIN, LOW);
29 
30  // Read the signal from the sensor: a HIGH pulse whose
31  // duration is the time (in microseconds) from the sending
32  // of the ping to the reception of its echo off of an object.
33  duration = pulseIn(ECHO_PIN, HIGH);
34 
35  // Convert the time into a distance
36  cm = (duration/2) *0.0343;     // Speed of sound 0.0343 cm/usec
37  myservo.write(60);
38  if (cm <= 10) {
39    myservo.write(120); // sets the servo position
40  }
41  delay(400);
42}

Call To Action

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