Published January 10, 2019 © MIT

NodeMCU-Based IoT Project: Connecting IR Sensor

The goal of this tutorial is to enable you to capture and send data to the Thingsio.ai cloud from NodeMCU.

BeginnerProtip10 hours11,065

NodeMCU-Based IoT Project: Connecting IR Sensor

Things used in this project

Hardware components

IR Sensor

NodeMCU ESP8266 Breakout Board

Software apps and online services

Arduino IDE

thingsio.ai

Story

HowIR sensor work....

Sensor Description and Connection

after watching the above video you will know how sensor work, like to detect the object in particular direction we have to set our IR sensor in that direction and we can set the detection range using the potentiometer that is mounted on IR sensor pcb.

now lets see the connection for our project.

GND -> GND

+5V -> +5V

O/P -> A0

here all highlighted pins belongs to sensor and other to nodemcu.

so these are the hardware connection, that we have to make and then

STEPS->

1) google thingsio.ai

2) register yourself (or) make an account

3) click on new project button on top menu

4) go to sample code option's --> nodemcu -->LM35 --> copy

5) paste it on arduino ide

6)declare variable that you want to sent to server

      int t; //comment the line "int t,t1,t2,t3;"

7) give your SSID and PASSWORD

  if(!wifiManager.autoConnect("abcd","*****"))        
           //wifiManager.autoConnect("AP-NAME", "AP-PASSWORD"); (OR) wifiManager.autoConnect("AP-NAME"); only ID no password (OR) wifiManager.autoConnect(); this will generate a ID by itself
  {    Serial.println("failed to connect and hit timeout");     //control comes here after long time of creating Access point "NodeMCU" by NodeMCU and still it has not connected //reset and try again, or maybe put it to deep sleep  
  ESP.reset();  
  delay(1000);  } 
//here in place of abcd give your ssid and in place of ******* give your password

8)in calculation part make all line comment except below two lines--> t=(analogValue/1024.0) * 5000;

Serial.println(t);

t=(analogValue/1024.0) * 5000; 
      // Serial.print("temp: ");  comment line's
     Serial.println(t);    
   //t2=(t1/10);     
   //Serial.print("celc: "); 
    //   Serial.println(t2);  
     // t3=((t2 * 9)/5 + 32);  
      //Serial.print("fhrn: "); 
       //Serial.println(t3);

9) change celc to your parameter name and t2 to t, delete others

String PostValue = "{\"device_id\":  61121695818, \"slave_id\": 2";     
    PostValue = PostValue + ",\"dts\":" +timestamp;
   PostValue = PostValue +",\"data\":{\"celc\":" + t2 +",\"fahr\":" + t3 +"}"+"}";
//+",\"fahr\":" + t3 <----- delete this part from above line

10) that's all we need to do now upload it to nodemcu board.

open your serial monitor and see whether http status is 200 or not if yes that means the data is successfully getting uploaded to the cloud and then check on cloud and analyse it.

Use's

we can use this kind of project in farming (field security), visitor counter, to keep a particular place secret.

if you have the knowledge of machine learning then you can also predict the future case's like in farming case -->

after so many days of implementing this system we will be having lot of data with us so we can make a nice dataset having feature's like time and "object entry"

and since this will be binary case like somebody is entering in your field or not (0 or 1) so by using logistic algorithm we can easily predict for the future time whether the person or animal will enter in field or not.

--> another example- take visitor counter

let's we keep this system on for months then we will get a good data history which will be having features like number of people's visit on which day and time.

so we can simply use linear regression or we can go with the poly also if dataset is more likely for poly, to predict how many peoples will visit tomorrow and accordingly we can arrange our place.

Code

#include <SoftwareSerial.h>
SoftwareSerial mySerial(12, 13); // RX, TX

#include <ESP8266WiFi.h>          //https://github.com/esp8266/Arduino
#include <DNSServer.h>
#include <ESP8266WebServer.h>
#include "WiFiManager.h"          //https://github.com/tzapu/WiFiManager
#include <WiFiClientSecure.h>

int count=0,i,m,j,k;
int t;//int t,t1,t2,t3;
int outputpin= A0;//ds18b20 

//////////////////////////////////////// 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];

WiFiClient client;


/////////////////////////////////////////////////////////////////////////////////////////////////////////
void configModeCallback (WiFiManager *myWiFiManager) 
{
  Serial.println("Entered config mode");             //*-*-*-*-*-*-*-*-*-*-*-*-*-*if control enters this function then net is not connected
  Serial.println(WiFi.softAPIP());                  // "WiFi.softAPIP() is for AP" , "WiFi.localIP() is for STA",
                                                                
  Serial.println(myWiFiManager->getConfigPortalSSID());             //if you used auto generated SSID, print it
}
/////////////////////////////////////// TIMESTAMP CALCULATION function///////////////////////////////////////
int GiveMeTimestamp()
{
  unsigned long timeout = millis();

  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);     //(19200,SERIAL_8E1) - data size = 8 bits , parity = Even , stop bit =  1bit
  mySerial.begin(115200);
  WiFiManager wifiManager;
 
  wifiManager.setAPCallback(configModeCallback);
                                                                                                    
  if(!wifiManager.autoConnect("abcd","*****"))                   //wifiManager.autoConnect("AP-NAME", "AP-PASSWORD"); (OR) wifiManager.autoConnect("AP-NAME"); only ID no password (OR) wifiManager.autoConnect(); this will generate a ID by itself
  {
    Serial.println("failed to connect and hit timeout");     //control comes here after long time of creating Access point "NodeMCU" by NodeMCU and still it has not connected
    //reset and try again, or maybe put it to deep sleep
    ESP.reset();
    delay(1000);
  } 

  //if you come here you have connected to the WiFi
  Serial.println("connected...yeey :");
 
}

void loop() 
{
  int analogValue = analogRead(outputpin);
{
 
 
  
/////////////////////////////////////// SEND THE QUERY AND RECEIVE THE RESPONSE///////////////////////  
 t=(analogValue/1024.0) * 5000;
        //Serial.print("temp: ");
        Serial.println(t);

//        t2=(t1/10);
//        Serial.print("celc: ");
//        Serial.println(t2);
//
//        t3=((t2 * 9)/5 + 32);
//        Serial.print("fhrn: ");
//        Serial.println(t3);        //break;

          

  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\":  61121695818, \"slave_id\": 2";
         PostValue = PostValue + ",\"dts\":" +timestamp;
   PostValue = PostValue +",\"data\":{\"Inform\":" + t+"}"+"}";
  
  
  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);
}
}