Soil Moisture Content Measurement Using Esp32 and Thingsio.ai Platform

In this tutorial I am going to explain about reading of the moisture content in the soil by using esp32 and then sending the values into the thingsio.ai IoT cloud platform.

COMPONENTS

Hardware Components:

1. esp32 development board

2.Soil sensor

3.Jumper Wires

Software:

1. Arduino IDE

2. Thingsio.ai

CONNECTIONS

Soil Moisture Sensor----------------------esp32 Board

VCC---------------------------------------3V3

GND--------------------------------------GND

A0----------------------------------------VP

CODING:

#include <WiFi.h>

#include <WiFiMulti.h>

#include<WiFiClientSecure.h>

int count=0,i,m,j,k;

int t;

int sensor_pin = A0;

int value ;

//////////////////////////////////////// ALL DECLARATIONS
for CLOUD //////////////////////////////

const char* host = "api.thingsai.io";                                 // OR host =
devapi2.thethingscloud.com

const char* post_url = "/devices/deviceData";       // OR
/api/v2/thingscloud2/_table/data_ac

const char* time_server =
"baas.thethingscloud.com";            
//this is to convert timestamp

const int httpPort = 80;

const int httpsPort = 443;

const char*  server =
"api.thingsai.io";  // Server
URL

char timestamp[10];

WiFiMulti WiFiMulti;

// Use WiFiClient class to create TCP connections

   WiFiClient client;

/////////////////////////////////////// TIMESTAMP
CALCULATION function///////////////////////////////////////

int GiveMeTimestamp()

  unsigned long
timeout = millis();

 // WiFiClient client;

  while
(client.available() == 0)

    if (millis() -
timeout > 50000)

      client.stop();

      return 0;

while (client.available())

        String line =
client.readStringUntil('\r');                   
//indexOf() is a funtion to search for smthng , it returns -1 if not
found

        int pos =
line.indexOf("\"timestamp\"");                       //search for
"\"timestamp\"" from beginning of response got and copy all
data after that , it'll be your timestamp

        if (pos >=
0)

          int j = 0;

         
for(j=0;j<10;j++)

           
timestamp[j] = line[pos + 12 + j];

////////////////////////////////////////////////////////////////////////////////////////////////////////

void setup()

   
Serial.begin(115200);

   
Serial.println("Reading From the Sensor ...");

   delay(2000);

    // We start by
connecting to a WiFi network

    WiFiMulti.addAP("Wifi_name",
"Wifi_Password");

    Serial.println();

    Serial.println();

   
Serial.print("Wait for WiFi... ");

   
while(WiFiMulti.run() != WL_CONNECTED) {

       
Serial.print(".");

        delay(500);

   
Serial.println("");

   
Serial.println("WiFi connected");

    Serial.println("IP
address: ");

   
Serial.println(WiFi.localIP());

    delay(500);

void loop()

/////////////////////////////////////// SEND THE QUERY AND
RECEIVE THE RESPONSE///////////////////////

       value=
analogRead(sensor_pin);

     // value =
map(value,550,0,0,100);

       
Serial.print("Mositure : ");

        
Serial.print(value);

         
Serial.println("%");

          
delay(1000);

 
Serial.print("connecting to ");

 
Serial.println(host);                          //defined upside :-
host = devapi2.thethingscloud.com or 139.59.26.117

///////////////////////////////////// TIMESTAMP CODE SNIPPET
/////////////////////////

Serial.println("inside get timestamp\n");

  if
(!client.connect(time_server, httpPort))

    return;                                                       
//*-*-*-*-*-*-*-*-*-*

 
client.println("GET /api/timestamp HTTP/1.1");                            //Whats this part
doing, i didnt get

 
client.println("Host: baas.thethingscloud.com");

 
client.println("Cache-Control: no-cache");

 
client.println("Postman-Token:
ea3c18c6-09ba-d049-ccf3-369a22a284b8");

  client.println();

GiveMeTimestamp();           
            //it'll call the
function which will get the timestamp response from the server

Serial.println("timestamp receieved");

Serial.println(timestamp);

 
Serial.println("inside ThingsCloudPost");

  String PostValue =
"{\"device_id\": 61121695918, \"slave_id\": 2";

        PostValue =
PostValue + ",\"dts\":" +timestamp;

   PostValue =
PostValue +",\"data\":{\"MOIST\":" + value
+"}"+"}";

 
Serial.println(PostValue);

/* create an instance of WiFiClientSecure */

WiFiClientSecure client;

   
Serial.println("Connect to server via port 443");

    if
(!client.connect(server, 443)){

       
Serial.println("Connection failed!");

    } else {

       
Serial.println("Connected to server!");

        /* create HTTP
request */

       
client.println("POST /devices/deviceData HTTP/1.1");

       
client.println("Host: api.thingsai.io");

       
//client.println("Connection: close");

       
client.println("Content-Type: application/json");

        client.println("cache-control:
no-cache");

       
client.println("Authorization: Bearer
eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.IjVhMzBkZDFkN2QwYjNhNGQzODkwYzQ4OSI.kaY6OMj5cYlWNqC2PNTkXs9PKy6_m9tdW5AG7ajfVlY");

       
client.print("Content-Length: ");

        client.println(PostValue.length());

       
client.println();

       
client.println(PostValue);

//////////////////////////////////POSTING the data on to the
cloud is done and now get the response form cloud server//////////////////

 Serial.print("Waiting for response
");

        while
(!client.available()){

            delay(50);
//

           
Serial.print(".");

        /* if data is
available then receive and print to Terminal */

        while
(client.available()) {

            char c = client.read();

           
Serial.write(c);

        /* if the
server disconnected, stop the client */

        if
(!client.connected()) {

           
Serial.println();

           
Serial.println("Server disconnected");

            client.stop();

Serial.println("//////////////////////    THE END    
/////////////////////");

delay(3000);

OUTPUT:

The Output of the code is shown.

GRAPH

This is the graphical representation of the values which are read from the sensor.

Soil Moisture using thingsio.ai and esp32

Here is the complete video of the project. Thank You.