CONTENT

A) Overview

B) Things used in this project

1. Hardware Components

2. Software, apps and online services

3. Hand Tools and Fabrication machines

C) Building

1. Coding the NodeMCU board  

1.1- Adding and selecting the ESP8266 board to the IDE

1.2 – Downloading and adding necessary libraries

1.2- Coding the Sanitizer Dispenser and Temperature Scanner 

2. IFTTT Setup

2.1- Getting WebHook Credentials

2.2- Creating an Applet

3. Coding the Bolt module

3.1 – Getting All the Credentials   

3.2– Creating the conf.py file.

3.3- Creating the high_temp.py file

4. Schematics and Connections

4.1- PCB Designing

4.2- External Connections  

 5.   Hardware

D) Demonstration

1. Testing the sanitiser dispenser and temperature detection.

2. Testing the calling and mail feature.

3. Flow Chart

4. Full Video  

                 OVERVIEW

The device’s primary aim is to lower the spread of the coronavirus disease. The device checks for the person’s temperature. If it is under the usual temperature, there is a blue led which lights up indicates that the temperature is normal and the person can go. In case the person’s temperature is high, a red led lights up and a buzzer is activated to ensure that the person and the people around him are aware that he/she has a high temperature. Along with that, an automatic mail and phone call is placed to the owner or the person in charge of the place where the device has been set up. In addition to that, the system dispenses sanitiser automatically as soon as the person places his/her hand in front of the sensor.  This prevents surface transmission, unlike the usual sanitiser dispersers. 

THINGS USED IN THE PROJECT

HARDWARE COMPONENTS

1. Bolt IOT Wi Fi Module
2. GY-906 MLX90614-BAA Non-Contact Infrared Temperature Sensor
3. Node-MCU/ ESP8266 Board (Any Arduino board would also work)
4. HC-SR04 Ultrasonic Sensor
5. 5V Submersible water pump motor
6. 5V Relay Module
7. 5mm LEDs – Red and Blue
8. Copper Wires
9. Jumper Wires (Male to Female, Male to Male) Female Pin Header Strip
10. USB A to Micro USB Cables – 2
11. Power Bank
12. 1 m Plastic Pipe
13.  Plastic Box
14. Custom Built PCB

SOFTWARES, APPS AND ONLINE SERVICES

1. Bolt Iot Android App
2. IFTTT
3. Ubuntu (Vagrant/Virtual Box)
4. Mailgun
5. EasyEDA
6. JLCPCB

HAND TOOLS AND FABRICATION MACHINES

1. Soldering Iron (Generic)
2. Solder Wire
3. Glue Gun
4. Hand Drill
5. Wire Stripper
6. Screw Drivers

BUILDING

1. CODING THE NODEMCU BOARD

In order to deploy our C++ code into the ESP8266 board , we need an IDE. For this, we will be using the Arduino IDE which can be downloaded from www.arduino.cc/en/software. 

1.2- Downloading and adding necessary libraries:

1.3-Coding the Sanitizer Dispenser and Temperature Scanner:

Well, I guess this is the part you were waiting for. I am going to explain the code part by part . Please do pay attention to the comments in the code as well.

So firstly, before the setup function, we need to import the libraries and declare the pins and variables. That’s what we are doing here.

/* IMPORTING THE LIBRARIES */ 
#include <ESP8266WiFi.h>
#include <Wire.h>
#include <Adafruit_MLX90614.h>
#include <Ultrasonic.h>
/* DECLARING THE VARIABLES */ 
int distance; //variable to store distance measured by the ultrasonic sensor 
float temp_f; //variable to store the temperature 

/* NAMINGS THE PINS AS PER THE OBJECTS CONNECTED TO IT */ 
#define triger D3 //the trigger pin of the ultrasonic sensor 
#define echo D4 //the echo pin of the ultrasonic sensor 
#define boltpin D6 //pin connected to pin 0 of bolt iot module
#define relayofmotor D5 //Pin connected to the relay which will help in acivating the motor 
#define greenled D7 //the led which I want to glow when the temperature is low 
#define buzzerandredled  D8 //the pin which is connected to the red led and the buzzer which is want to activate of the temperature is high. 
/*DECLARING THE SENSOR OBJECTS*/ 
Ultrasonic ultrasonic(triger, echo); //Creating an ultrasonic sensor object with the trigger and echo pins as the parameters 
Adafruit_MLX90614 mlx = Adafruit_MLX90614();//creating a temperature sensor object

One  question which might come up to your mind is that why have we declared the temperature variable as a float and not an integer. Well, it is because float is a datatype which can even store decimals unlike an integer. Because most of the times the temperature is a decimal number, I have used a float instead of an int.

Next, we move on to the setup function. All the code in the setup function is just run once in the start.  This is where we declare of the pins are output or input and also do other basic things like starting the sensor.

void setup() {
  Serial.begin(9600);//Starting the serial monitor at 9600 baud 
  mlx.begin();//starting the sensor 
  /* DECLARING THE OUTPUT PINS */ 
  pinMode(relayofmotor, OUTPUT); 
  pinMode(boltpin, OUTPUT); 
  pinMode(greenled, OUTPUT); 
  pinMode(buzzerandredled, OUTPUT); 
}

Now we move on to the loop function. The code inside this function continuously runs.  

void loop() {
  distance = ultrasonic.read(); //Stores the distance in cm  measured by in ultrasonic sensor in the variable 
  temp_f = mlx.readObjectTempF(); //Stores the temperature in fahrenheit measured by in temperature sensor the variable 
  if (distance<8){ // This set of code will run if the distance is less than 8 which means someone's hand is below the device
     
      if (temp_f>98.6 and temp_f<1500){ //person is in front of the sensor and temperature is higer than usual. Errors are also avoided as if the temperature value is 1500, it means there is an issue with the sensor. 
      digitalWrite(boltpin, HIGH);
      digitalWrite(relayofmotor, HIGH); 
      digitalWrite(buzzerandredled, HIGH); 
      delay(1000); 
      digitalWrite(relayofmotor, LOW); 
      delay(1000); 
      digitalWrite(buzzerandredled, LOW); 
      delay(11000); 
      digitalWrite(boltpin, LOW);
    }
    if (temp_f<98.5 and temp_f<1500){ // person is in  of sensor but temperature ok 
    digitalWrite(relayofmotor, HIGH); 
    digitalWrite(greenled, HIGH);
    delay(1000); 
    digitalWrite(relayofmotor, LOW); 
    delay(10000); 
    digitalWrite(greenled, LOW); 

  } 

}
}

In the set of code above, firstly I have stored the values of the distance and temperatures in their respective variables. I have done it in the loop and not the setup function because I want them to be updated every time.

You might have noticed that I have made use of the if conditional many times. This is because I want a separate set of actions to be performed depending on the response form the sensors. So firstly, all the code in the loop function is surrounded by an if conditional which checks if the person’s hand is below the ultrasonic sensor. This means that if the distance is less than 8cm, then the rest of the code will run otherwise it will not.

Then comes the first conditional. It is when the temperature of the person is higher than 98.6 degree AND lower than 1500 degree. In this case the pins for the redledandbuzzer, the relay for the motor and the bolt turn high and then low after a specific time.

On the other hand, if the person’s temperature is below 98.6 degree, only the sanitiser dispenses and the green led glows for which the pins for the  green led and for the relay turn high and then low.  

You would be having 2 possible questions here. Firstly, you might ask that why have we added that second conditional that the temperature is below 1500.It is because if there is any loose connection or short circuit in the sensor, it sends the value 1500. So just to make sure that the device does not falsely determine someone to have a high temperature, I have added this conditional.

Secondly, you might be wondering what this boltpin is but don’t, I’m going to explain it to you as well. So what I have done is that I have connected the D6 pin or the boltpin of the NodeMCU to the pin 0 of the bolt iot module. I have done this because I am also running a python script on the Bolt IOT module and I have programmed it in such a way that when the pin 0 of Bolt Module is high, a mail will be sent along with a call to a specified individual. In the steps below, I’m going to show and explain how can we set up those automated calls and emails. 

2. IFTTT SETUP

IFTTT stands for If This Then That and it is a very nice online service which will help us in this project. So Before we proceed, we first need to create an account on IFTTT and we can do that by heading over to https://ifttt.com/. Also, as we will be using the VoIP Calls facility, we need to have the IFTTT app installed on our smartphone. It can easily be installed from Play Store on Android and through the App Store for IOS.

2.1 Getting the WebHook credentials:

2.2 Creating the Applet

3.CODING THE BOLT MODULE

Now in this section, we will be seeing how the device is able to perform the best and most useful functions of placing the call by calling the IFTTT webhook and sending automated emails using Mailgun.

3.1 Getting all The Credentials

Before we start uploading code onto the Bolt Module , we should collect all the required credentials.

B) MAILGUN CREDENTIALS: We will be using an online service named Mailgun for sending the automated email. Firstly sign up or login by heading over to https://www.mailgun.com/. Then start off by creating a sending domain. Once you have done that, go to Sending>>Do mains and click on your sending domain. Firstly you would see your Sandbox URL  which is something like sandboxXXXX.mailgun.org. Your sender email is test@yourSandboxURL.

3.2 Creating the conf.py file

3.2 Creating the high_temp.py file

As before, we will create a new file using nano high_temp.py. Before I show you the code, let me explain to you what we expect from it. Firstly, what we want is that the code gets the status of the pin 0. We know that if the person has a high temperature, the D6 pin of the NodeMCU which is connected with the digital pin 0 of the Bolt module turns high. So if the status is high, we want to send an email using mailgun and also make a web request which places the call via IFTTT. Also, also want to print the response for troubleshooting cases.

Here is the code:

# IMPORTING THE LIBRARIES 
import requests ##library which will help in making web request 
import conf # the file with all the credentials 
from boltiot import Email, Bolt #Bolt Iot libraries 
import json, time #Other libraries which  we will need


mybolt = Bolt(conf.API_KEY, conf.DEVICE_ID) # establishing connection with the bolt module 
mailer = Email(conf.MAILGUN_API_KEY, conf.SANDBOX_URL, conf.SENDER_EMAIL,conf.RECIPIENT_EMAIL)#creating the mailer object 

while True:
    response = mybolt.digitalRead('0')#Pin high when high temperature and pin low when low temperature  
    data = json.loads(response #Loading the data  
    decision = data['value'].rstrip() # decosion will be 1 for high temperature and 0 for low temperature 
    if decision == "1": #if person has high temperature 
        print("Arranging Phone Call")
        r= requests.get("http://maker.ifttt.com/trigger/makecall/with/key/lC5kvr7aPRfsnzUe6diZygd7vthmOn0Oa530qvbw-lm") #Calling the webhook 
        print("Making request to Mailgun to send an email")
        response = mailer.send_email("Alert!", "Someone whith a high temperature has just entered the building.") # ("Subbect", "Body")
        response_text = json.loads(response.text)#response from mailgun 
        print("Response received from Mailgun is: " + str(response_text['message'])) #printing the response for troubleshooting purpouses 

    elif decision =="0":
        print("low temperature")
    else:
        print("error")

    time.sleep(4)#code executes again after 4 seconds. 

4.SCHEMATICS AND CONNECTIONS

 4.1 – PCB Designing

This is a schematic of the PCB:

PS: Instead of connecting the pins in the schematics, I have added net ports so that it is neater and easier to understand. 

4.2 External Connections:

The above schematic is just of the PCB and of the pins which would be attached to it. There were also a few more connections left for which I am making a diagram below. Please note that the below connections are the external ones, the rest of the connections have been implemented into the PCB.

In the above schematic, I have shown the external connections.It is mainly the connection between the bolt module, relay and NodeMCU. The 3 input pins of the relay had been soldered in the PCB. Now when the replay turned high, I wanted the submersible motor inside the sanitiser container to work. So I connected the Ground of the Motor to ground of the Bolt Module. The 5v of the motor was connected to NC of the relay which is stands for normally closed and the 5v of the Bolt Module was connected to the COM port of the relay. In this way, whenever I programmed the relay to become high, the motor turned on.  

5. HARDWARE

There were a few parts  whose placing plays an important role. I just wated to show them to you as well.

MOTOR:

TEMPERATURE SENSOR:

 I have placed the temperature sensor at the top of the device so that the user does not have to bend to get his/her temperature scanned. I used a hand drill to make a hole for the sensor.

DEMONSTRATION

Before I start testing, I have uploaded the code on the nodeMCU board with the Arduino IDE, run the python script on my laptop and lastly connected the device with a power bank.

1.Testing the sanitiser dispenser and temperature detection.

In order to check if the temperature sensor and the sanitiser dispenser were working properly, I used the ambient room temperature in one case and a hot glass of water to stimulate the high temperature. The results were exactly as expected. In the first case, the blue led lit up and the sanitiser was dispensed and in the second case, the buzzer and red led were triggered along with the sanitiser dispensing.

CASE 1:

2.Testing the Mail and Calling Feature.

To test if these 2 key features  were working , I ran the python script on my laptop. I first checked the terminal as the status was being printed there.

This is how the terminal looked like. It showed error in the starting because the device wasn’t powered on.

This is the automated notification which was sent on the phone by IFTTT.:

This is the automated mail which was sent:

And lastly, this is the call which was placed.

3.Flow Chart

I also wanted to show you the entire flow of the project in case you had any confusions.

4.FullVideo

If you want to see this entire project in action, click HERE .