Soil Moisture Content Measurement Using Esp32 and Thingsio.ai Platform
by kavya_vaskoty in Circuits > Microcontrollers
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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.

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