Team Yayi Make:

•

Seydou Gnali Ousman

Published May 16, 2020

Connected Visor

A connected protective visor which helps to respect preventive measures against COVID-19.

IntermediateWork in progress6 hours8,869

Grand Prize Winners

The COVID-19 Detect & Protect Challenge

The Hackster Impact Detect Award

The COVID-19 Detect & Protect Challenge

Things used in this project

Hardware components

Arduino Nano R3

HC-05 Bluetooth Module

Ultrasonic Sensor - HC-SR04 (Generic)

MLX90614

Buzzer, Piezo

9V battery (generic)

9V Battery Clip

Switch Actuator, Head for spring return push-button

Jumper wires (generic)

LED (generic)

Resistor 221 ohm

Android device

Software apps and online services

MIT App Inventor 2

Autodesk Fusion

Arduino IDE

Hand tools and fabrication machines

3D Printer (generic)

Soldering iron (generic)

Story

Overview

In the fight against Covid 19 WHO recommends the following preventive measures:

Wash hands regularly for 20 seconds
Do not touch the face
Keep a social distance at least 1 meter...

Thanks to our open source connected visor, the user will be able to protect his face, keep a social distance of 1 meter, wash his hands properly for 20 seconds and monitor his body temperature.

Connected visor

Visor features

We have developed a tool that allows you to protect yourself and respect the preventive measures against Covid 19 composed of an ultrasonic sensor (HC-sr04) to measure the distance, an infrared thermometer (MLX90614) to monitor its temperature, a led and a piezoelectric speaker to alert and guide the user, a bluetooth module to connect the visor to its mobile application.

By placing your hand 10 cm from the visor for 10 seconds, the visor automatically activates a 20 second timer to help you wash your hand: this is the hand washing timer function.

The mobile application allows you to display the measured body temperature on the forehead of the person wearing the visor, to activate or deactivate the following functions:

Hand washing timer
Mute mode.

How it's work

The thermometer sensor (MLX90614) is placed 2 cm from the forehead and the distance sensor (HC - sr04) is placed in front of the visor.

Sensor placement

Demonstration

Schematics

Code

Firmware

#include <Wire.h>
#include <Adafruit_MLX90614.h> // adafruit library
#include <SoftwareSerial.h>

SoftwareSerial serieBT(10, 11); //RX TX define
Adafruit_MLX90614 mlx = Adafruit_MLX90614();

const int trigPin = 4;
const int echoPin = 3;
long duration;
int distance;
int a=0;

bool Handwash = true;
bool Sound = true;

char junk;
String inputString="";
char c;
String Data;
int i=0;

unsigned long intervall2 = millis(); 


void setup() 
{
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT); 
  pinMode(5, OUTPUT); 
  pinMode(6, OUTPUT); 
  Serial.begin(9600);
  mlx.begin();  
  serieBT.begin(9600); 
  }

void loop() {
  // the bluetooth is used to configure the visor throuth the mobile application
  if(serieBT.available()){
    while(serieBT.available())
    {
      char inChar = (char)serieBT.read(); //read the input 
      inputString += inChar;        //make a string of the characters coming on serial
      }
    while (serieBT.available() > 0)  
    {
      junk = serieBT.read();
      }

    // if message is 1a the visor desactive handwash function
    if(inputString == "1a\r\n"){
      Handwash = false;
      }
    // if message is 1b the visor active handwash function
    if(inputString == "1b\r\n"){
      Handwash = true;
      }
    // if message is a the visor active the piezo speaker in the social distance function
    if(inputString == "a\r\n"){
      Sound = true;
      }
    // if message is a the visor desactive the piezo speaker in the social distance function
    if(inputString == "b\r\n"){
      Sound = false;
      }
    inputString = "";
    }
 
   else{ 
    Serial.print("ok ");
    if(millis()>intervall2+10000){ 
        serieBT.print(mlx.readAmbientTempC()); //the temperature is send every 10 second to the application to displaying
        intervall2 = millis();
        }
    fdistance();
    delay(200);
    //the function who active handwash funtion if you placed 
    if(i >8){
        if (Handwash) hand();
        else i = 0; 
        }
       }
  }

// function distanciation social 1 meter
void fdistance(){
  digitalWrite(trigPin, LOW);delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin, HIGH);
  distance= duration/58.2;
  Serial.println(distance);
  delay(100);
  if(distance<=100){
    digitalWrite(5, HIGH);
    if(Sound){
      digitalWrite(6, HIGH);
      }
    if (distance <10){
      i++;
      }
    }
  else if(distance> 100){
    digitalWrite(5, LOW);
    digitalWrite(6, LOW);
    }
}

//handwashing timer function (20 sec)
void hand (){
  unsigned long currentMillis = millis();
  unsigned long intervall = currentMillis + 20000; 
  i = 0;

  //the piezo speaker sound three time to warn user that he can start washing hand

  digitalWrite(6, LOW);
  delay(200);
  digitalWrite(6, HIGH);
  delay(200);
  digitalWrite(6, LOW);
  delay(200);
  digitalWrite(6, HIGH);
  delay(200);
  digitalWrite(6, LOW);
  delay(200);
  digitalWrite(6, HIGH);
  delay(200);
  digitalWrite(6, LOW);

  //20 second timer
  while(millis()<intervall)
  {
    Serial.print("hand");
    digitalWrite(5, HIGH);
    }
    
   //the piezo speaker sound three time to warn user that he can stop washing hand
  digitalWrite(6, HIGH);
  delay(200);
  digitalWrite(6, LOW);
  delay(200);
  digitalWrite(6, HIGH);
  delay(200);
  digitalWrite(6, LOW);
  delay(200);
  digitalWrite(6, HIGH);
  delay(200);
  digitalWrite(6, LOW);
  }