Luis Eduardo Arenas DeseanoJaphet Lopez
Published

Arduino Sigfox: School Warden to Monitor the Environment

This project is for monitor the air and UV conditions of the environment before the children go to recess.

IntermediateWork in progressOver 2 days949

Things used in this project

Hardware components

DevKit Sigfox NXTIoT
×1
6 Volt 4.5 Ah Sealed Lead Acid Rechargeable Battery -
×1
Adafruit Standard LCD 16x2
×1
Adafruit i2c / SPI character LCD backpack
×1
Altoids tin
Altoids tin
A SMALL BOX TO PROTEC THE UV SENSOR
×1
MQ135 Gas Sensor for Air Qaulity (ER-SEN17850M) Digital / Analog output
×1
MQ8 Gas Sensor for Hydrogen
×1
UV sensor
×1
DC Power Monitor DC 0-100 V Voltage Meter LED green
×1
Medium Orange Plastic Mechanical Push Button
×1
Switch button 2 positions
×1
4 in. (102mm) Satin Nickel Wire Drawer Pull
×1

Software apps and online services

Arduino IDE
Arduino IDE
Sigfox
Sigfox
Ubidots
Ubidots

Hand tools and fabrication machines

Variety Screwdriver Set (6-Piece)
4g Ultra Gel Control Super Glue Bottle
or a hot glu gun
Hammer
5.5-Amp Corded 3/8 in. Variable Speed Compact Drill/Driver with Bag
Dremel
8 in. Wire Stripper and Cutter and Crimper
Electric welding pencil

Story

Read more

Custom parts and enclosures

All the dimentions from the proyect

you just need to unzip the file an the open with catia or with solidworks

MainBox

TopBox

Schematics

Schematic

Code

Code for school warden

Arduino
/* PROJECT: THE SCHOOL WARDEN WITH SIGFOX
 * AUTOR: LUIS ARENAS
 * EMAIL: WICHOMW3@HOTMAIL.COM
 * 
 */
#include <LiquidCrystal_I2C.h> // library for the I2C DISPLAY
#include<Wire.h> // library for the comunication by I2C

#define PIN_GUVAS12SD A2 // Pin al que se conecta el módulo con el UVM30A
#define ESPERA_ENTRE_LECTURAS 100 // Leer cada 100 ms // Read every 100 ms
#define ESPERA_ENTRE_PRESENTACIONES 10000 // Mostrar el índice cada 10 s // show every 10 seconds the average
#define CANTIDAD_INDICES_UV 12 // cuantity of UV levels *you can change it 
#define CANTIDAD_INDICES_CO2 6 // cuantity of CO2 levels *you can change it

LiquidCrystal_I2C lcd(0x3F,16,2); // define the I2C Direction (Direction in hexadecimal,witdh,height)


unsigned int lectura_sensor; //variable to read the analog value of uv sensor
unsigned int contador_lecturas=1; // counter of lectures for uv sensor
unsigned int contador_lecturas2=1; // counter of lectures for MQ135
float total_lecturas=0.0; // the sum of all lectures from uv sensor
float media_lecturas;   // keep the average from the uv sensor values
float total_lecturas_mq135=0.0; // the sum of all the lectures from MQ135
float media_lecturas_mq135; // the average form the MQ135 values
int valor_indice_uv[CANTIDAD_INDICES_UV]={0,210,295,378,467,563,646,738,818,907,1003,1022}; // ranges of Uv values from 0 to 11 * you can change it 
int valor_indice_CO2[CANTIDAD_INDICES_CO2]={0,8,11,16,19,23};  // ranges of CO2 from 0 to 6 * you can change it 
byte indice; // variable to keep the number of the array of UV
byte indice2; // variable to keep the number of the array of CO2
boolean buscando_indice_uv; // Varible that turns true when the average of uv is greater than some value of the uv array
boolean buscando_indice_CO2; // Varible that turns true when the average of CO2 is greater than some value of the CO2 array
long cronometro_lecturas; // take the time that has been passed between lectures
long cronometro_presentaciones; // take the time that has been passed when the info is showed
long tiempo_transcurrido; // take the time that have been passed

const int boton=6;//default pin for the boton just for this model
const int led=7; // default pin for the LED just for this model
char RespuestaSigfox[50]; // The String for the message
const int mq135=A0; // define the analog pin for the MQ135 sensor
const int mq8=A1; // define the analog pin for the MQ8 sensor

int sensor1=0; // variable to keep the value of MQ135 and add to the message for sigfox
int sensor2=0; //variable to keep the value of MQ8 and add to the message for sigfox
int sensor3=0; //variable to keep the value of UV and add to the message for sigfox

float sensor11=0; // variable to read the analog value of MQ135
float sensor22=0; // variable to read the analog value of MQ8

int ban=0;
long RO=68760; // value obtained by the operation with a rule of three with the video 
float RS_mq135=0; // value of the resistence S for MQ135
float RS_mq8=0; // value of the resistence S for MQ8
int ppm_mq135=0; // value of ppm for MQ135 * you can change it to long if you want
long ppm_mq8=0; // value of ppm for MQ8 
float var11; // value of divide RS from MQ8 with RO
float var22; // value of divide RS from MQ135 with RO

void setup() {
 
  Serial.begin(9600); // begin the port Serial in the arduino
  pinMode(boton, INPUT); // define the pin boton like input
  pinMode(7, OUTPUT);  // define the pin LED like output
  pinMode(mq135,INPUT); // define the analog pin for MQ135
  pinMode(mq8,INPUT);  // define the analog pin for MQ8
   //pinMode(PIN_GUVAS12SD,INPUT); // La lectura analógica no necesita inicialización
  lectura_sensor=analogRead(PIN_GUVAS12SD); // The first lecture is an error
  cronometro_lecturas=millis(); // wait one round of read to stabilize the sensor
  cronometro_presentaciones=millis();

   // define a welcome message
   lcd.init();
  lcd.backlight();
  lcd.clear();
  lcd.setCursor(0,0);
  lcd.print("WELCOME");
  lcd.print(" SIGFOX");
  delay(3000);
  lcd.clear();
  lcd.setCursor(0,0);
  lcd.print("Processing info");
  lcd.setCursor(0,1);
  lcd.print("Please Wait...");
 }

void enviar_sigfox(int x, int y, int z) // this funtion converts he 3 values of the sensors to hexadecimal and add to the sigfox message to send it
{
  String cad1;
  String cad2;
  String cad3;
  String bufer="AT$SF=";
  char payload[20];
  Serial.print("Enviar/send: ");
  Serial.println(x);
  Serial.println(y);
  Serial.println(z);
  cad1=String(x, HEX);
  cad2=String(y, HEX);
  cad3=String(z, HEX);  
  //convierte el dato a bytes y lo agrega a nuestro mensaje a enviar
  String cadena;
  cadena=cad1+cad2+cad3;
  //str1=  String(sensor1, HEX);  
  Serial.println(cadena);
  bufer+=cadena;
  
  bufer.toCharArray(payload,16);
  //
  digitalWrite(7, HIGH);
  delay(1000);
  enviarcomandoATSigfox("AT");
  enviarcomandoATSigfox("AT$RC");
  enviarcomandoATSigfox(payload);
  digitalWrite(7, LOW);
}


void loop() {

  tiempo_transcurrido=millis()-cronometro_lecturas;
  
  if(tiempo_transcurrido>ESPERA_ENTRE_LECTURAS) // read every time that the millis pass the value stablish in the top
  {
    cronometro_lecturas=millis();
    lectura_sensor=analogRead(PIN_GUVAS12SD); // read the value of th esensor
    lectura_sensor=(lectura_sensor*1100)/225.06; // converts the value to de real value in volts from the sensor, because the sensor just reach lectures of 1.1 volts 

    //to calculate the value of MQ135
    sensor11=analogRead(mq135);
     sensor11=(sensor11*5.0)/1023.0;
     RS_mq135=1000*((5-sensor11)/sensor11);
     var22=RS_mq135/RO;
      ppm_mq135=5.0908*(pow(var22,-0.343));

          
    total_lecturas_mq135+=ppm_mq135; //to sum the value of MQ135 to a variable
    total_lecturas+=lectura_sensor; // to sum the valur of UV to a variable
    media_lecturas=total_lecturas/contador_lecturas++; //divade the sum of the value obtained with the count of readings 
    media_lecturas_mq135=total_lecturas_mq135/contador_lecturas2++; //divade the sum of the value obtained with the count of readings 
   
  }
  tiempo_transcurrido=millis()-cronometro_presentaciones;
  if(tiempo_transcurrido>ESPERA_ENTRE_PRESENTACIONES) // if the millist are greater than the time to prresente the total
  { // substract all the information of the ranges
    cronometro_presentaciones=millis();
    buscando_indice_uv=true;
    buscando_indice_CO2=true;
    indice=CANTIDAD_INDICES_UV;
    indice2=CANTIDAD_INDICES_CO2;
    while(buscando_indice_uv&&indice>0) // look for the value from the greatest to the lowest
    {
      indice--;
      if(media_lecturas>valor_indice_uv[indice]) // if the average is higher than that value readed
      {
        
        buscando_indice_uv=false;  //active the flag
      }
    }
    while(buscando_indice_CO2&&indice2>0) // if the average is higher than that value readed
    {
      indice2--;
      if(media_lecturas_mq135>valor_indice_CO2[indice2]) 
      {
        
        buscando_indice_CO2=false; // active the flag
      }
    }

    // if you want to see the values in the serial  monitor but if you are using sigfox you must be to desactivated
    /*Serial.print("Lectura sensor: "+String(media_lecturas,DEC));
    Serial.print(" (media de "+String(contador_lecturas,DEC)+")");
    Serial.print (" Lectura de mq135: "+String(media_lecturas_mq135,DEC)+"");
    Serial.print(" (media de "+String(contador_lecturas2,DEC)+")");
    Serial.print (" sensor de mq135: "+String(analogRead(mq135),DEC)+"");
    Serial.print (" sensor de mq8: "+String(analogRead(mq8),DEC)+"");
    Serial.println(" Índice UV: "+String(indice,DEC));
    Serial.println(" Índice CO2: "+String(indice2,DEC));
    */ 
//-----------------------------------------------------
    
     lcd.clear(); // clean the display
    sensor22=analogRead(mq8);
    sensor22=(sensor22*5.0)/1023.0; // transform the analog value into voltage by a rule of three
    RS_mq8=1000*((5-sensor22)/sensor22); // this operation is for obtain RS value - the value of 1000 is a constant obtained by the resisitence between  voltage and analog port
    var11=RS_mq8/RO; // a pre division of the final operation
    ppm_mq8=20163*(pow(var11,-1.438)); // this operation is the equation obtained by excel

   // show the results on the display
      lcd.setCursor(0,0); 
      lcd.print("CO2:");
      lcd.print((int)media_lecturas_mq135);

      lcd.setCursor(7,0);
      lcd.print("H:");
      lcd.print(ppm_mq8);

      lcd.setCursor(12,1);
      lcd.print((int)media_lecturas);
// this switch is for know the value of the place in the array of UV sensors
      switch (indice){
       case 1: 
              lcd.setCursor(0,1);
               lcd.print("LEVEL UV 1");
               sensor3=18;
               break;
        case 2:
               lcd.setCursor(0,1);
               lcd.print("LEVEL UV 2");
               sensor3=19;
               break;
         case 3:
               lcd.setCursor(0,1);
               lcd.print("LEVEL UV 3");
               sensor3=20;
               break;
         case 4:
               lcd.setCursor(0,1);
               lcd.print("LEVEL UV 4");
               sensor3=21;
               break;
         case 5:
               lcd.setCursor(0,1);
               lcd.print("LEVEL UV 5");
               sensor3=22;
               break;
          case 6:
               lcd.setCursor(0,1);
               lcd.print("LEVEL UV 6");
               sensor3=23;
               break;
          case 7:
               lcd.setCursor(0,1);
               lcd.print("LEVEL UV 7");
               sensor3=24;
               break;
          case 8:
               lcd.setCursor(0,1);
               lcd.print("LEVEL UV 8");
               sensor3=25;
               break;
          case 9:
               lcd.setCursor(0,1);
               lcd.print("LEVEL UV 9");
               sensor3=26;
               break;
          case 10:
               lcd.setCursor(0,1);
               lcd.print("LEVEL UV 10!!");
               sensor3=27;
               break;
          case 11:
               lcd.setCursor(0,1);
               lcd.print("LEVEL UV 11!!!");
               sensor3=28;
               break;
         case 0:
               lcd.setCursor(0,1);
               lcd.print("LEVEL UV 0");
               sensor3=17;
               break;      
      }
      // this switch is for know the place of the array of the MQ135 sensor
            switch (indice2){
       case 1: 
               sensor1=18;
               break;
        case 2:
              sensor1=19;
               break;
         case 3:
               sensor1=20;
               break;
         case 4:
               sensor1=21;
               break;
         case 5:
               sensor1=22;
               break;
         case 0:
               sensor1=17;
               break;      
      }
    // this part is for have a range for the MQ8 sensor
    if(ppm_mq8<300000){
    sensor2=17;
    }

    else if(ppm_mq8>300000 && ppm_mq8<360000){
      sensor2=17;
    }
    else if(ppm_mq8>450000 && ppm_mq8<850000){
      sensor2=18;
    }
    else if(ppm_mq8>950000 && ppm_mq8<1500000){
      sensor2=19;
    }
    else if(ppm_mq8>1500000){
      sensor2=19;
    }

    //restar the counters and the average for MQ135 and UV sensor
    contador_lecturas=1;
    contador_lecturas2=1;
    total_lecturas=0.0;
    total_lecturas_mq135=0.0;
  }








  
  if (digitalRead(boton)==LOW) // if the boton is pressed we send the values to sigfox
  {
    enviar_sigfox(sensor1,sensor2,sensor3);
    delay(2000);
  }
}

  void enviarcomandoATSigfox(char* comandoAT){ //tis funtion call the sigfox module to send the message 
  unsigned long x=0;
 while( Serial.available() > 0) Serial.read();
  x = 0;
  memset(RespuestaSigfox, '\0',sizeof(RespuestaSigfox)); 
  Serial.print(comandoAT);
  Serial.print("\r\n");
  while(true){
    if(Serial.available() != 0){   
      RespuestaSigfox[x] = Serial.read();
      x++;
      if (strstr(RespuestaSigfox, "\n") != NULL){
        break;
      }
    }
  }
}

Credits

Luis Eduardo Arenas Deseano

Luis Eduardo Arenas Deseano

2 projects • 3 followers
I am a mechatronic, in communications and electronics engineer. Specialist in IoT, mobile conectivity and service robotics.
Japhet Lopez

Japhet Lopez

1 project • 2 followers

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