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Kutluhan Aktar
Published © CC BY

IoT AI-driven Yogurt Processing & Texture Prediction | Blynk

Collect environmental factors and culture amount while producing yogurt. Then, run a neural network model via Blynk to predict its texture.

ExpertFull instructions provided4,963

Things used in this project

Hardware components

Seeed Studio XIAO ESP32C3
×1
Seeeduino XIAO Expansion board
Seeed Studio Seeeduino XIAO Expansion board
×1
Seeed Studio Grove - Temperature&Humidity Sensor (SHT40)
×1
Seeed Studio Grove - Integrated Pressure Sensor Kit
×1
Gravity: I2C 1Kg Weight Sensor Kit - HX711
DFRobot Gravity: I2C 1Kg Weight Sensor Kit - HX711
×1
Adafruit Waterproof DS18B20 Digital temperature sensor
Adafruit Waterproof DS18B20 Digital temperature sensor
×1
MicroSD Card
×1
Creality Sermoon V1 3D Printer
×1
Creality Sonic Pad
×1
Creality CR-200B 3D Printer
×1
SparkFun Solder-able Breadboard - Mini
SparkFun Solder-able Breadboard - Mini
×1
4.7K Resistor
×1
Xiaomi 20000 mAh 3 Pro Type-C Power Bank
×1
M3 Screw and Hex Nut
×4
Grove - 4 pin Male Jumper to Grove 4 pin Conversion Cable
Seeed Studio Grove - 4 pin Male Jumper to Grove 4 pin Conversion Cable
×1
Jumper wires (generic)
Jumper wires (generic)
×1

Software apps and online services

Edge Impulse Studio
Edge Impulse Studio
Blynk
Blynk
Arduino IDE
Arduino IDE
Thonny
Fusion
Autodesk Fusion
Ultimaker Cura

Hand tools and fabrication machines

Hot glue gun (generic)
Hot glue gun (generic)

Story

Read more

Custom parts and enclosures

IoT_Yogurt_Processing_main_case.stl

IoT_Yogurt_Processing_front_cover.stl

Edge Impulse Model (Arduino Library)

Schematics

Schematic

Code

AI_yogurt_processing_data_collect.ino

Arduino
         /////////////////////////////////////////////  
        //    IoT AI-driven Yogurt Processing      //
       //      & Texture Prediction w/ Blynk      //
      //             ---------------             //
     //             (XIAO ESP32C3)              //           
    //             by Kutluhan Aktar           // 
   //                                         //
  /////////////////////////////////////////////

//
// Collect environmental factors and the culture amount while producing yogurt. Then, run a neural network model via Blynk to predict its texture.
//
// For more information:
// https://www.theamplituhedron.com/projects/IoT_AI_driven_Yogurt_Processing_Texture_Prediction
//
//
// Connections
// XIAO ESP32C3 :  
//                                Grove - Temperature & Humidity Sensor
// A4   --------------------------- SDA
// A5   --------------------------- SCL
//                                Grove - Integrated Pressure Sensor
// A0   --------------------------- S
//                                Gravity: I2C 1Kg Weight Sensor Kit - HX711
// A4   --------------------------- SDA
// A5   --------------------------- SCL
//                                DS18B20 Waterproof Temperature Sensor
// D6   --------------------------- Data
//                                SSD1306 OLED Display (128x64)
// A4   --------------------------- SDA
// A5   --------------------------- SCL
//                                MicroSD Card Module (Built-in on the XIAO Expansion board)
// D10  --------------------------- MOSI
// D9   --------------------------- MISO
// D8   --------------------------- CLK (SCK)
// D2   --------------------------- CS (SS)  
//                                Button (Built-in on the XIAO Expansion board)
// D1   --------------------------- +


// Include the required libraries:
#include <FS.h>
#include <SPI.h>
#include <SD.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <SensirionI2CSht4x.h>
#include <DFRobot_HX711_I2C.h>
#include <OneWire.h>
#include <DallasTemperature.h>

// Initialize the File class:
File myFile;
// Define the CSV file name: 
const char* data_file = "/yogurt_data.csv";

// Define the 0.96 OLED display (SSD1306) on the XIAO Expansion board. 
#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels
#define OLED_RESET    -1 // Reset pin # (or -1 if sharing Arduino reset pin)

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

// Define the Grove - Temperature & Humidity Sensor object.
SensirionI2CSht4x sht4x;

// Define the HX711 weight sensor.
DFRobot_HX711_I2C MyScale;

// Define the DS18B20 waterproof temperature sensor settings:
#define ONE_WIRE_BUS D6
OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature DS18B20(&oneWire);

// Define minimum and maximum pressure thresholds for the Grove - Integrated Pressure Sensor depending on the initial sensor measurements.
#define pressure_s_pin A0
int rawValue;
int offset = 221; // minimum (adjust)
int fullScale = 8360; // maximum (adjust)
 
// Define monochrome graphics:
static const unsigned char PROGMEM _error [] = {
0x00, 0x00, 0x00, 0x00, 0x00, 0x3F, 0xFC, 0x00, 0x00, 0xE0, 0x07, 0x00, 0x01, 0x80, 0x01, 0x80,
0x06, 0x00, 0x00, 0x60, 0x0C, 0x00, 0x00, 0x30, 0x08, 0x01, 0x80, 0x10, 0x10, 0x03, 0xC0, 0x08,
0x30, 0x02, 0x40, 0x0C, 0x20, 0x02, 0x40, 0x04, 0x60, 0x02, 0x40, 0x06, 0x40, 0x02, 0x40, 0x02,
0x40, 0x02, 0x40, 0x02, 0x40, 0x02, 0x40, 0x02, 0x40, 0x02, 0x40, 0x02, 0x40, 0x02, 0x40, 0x02,
0x40, 0x02, 0x40, 0x02, 0x40, 0x02, 0x40, 0x02, 0x40, 0x03, 0xC0, 0x02, 0x40, 0x01, 0x80, 0x02,
0x40, 0x00, 0x00, 0x02, 0x60, 0x00, 0x00, 0x06, 0x20, 0x01, 0x80, 0x04, 0x30, 0x03, 0xC0, 0x0C,
0x10, 0x03, 0xC0, 0x08, 0x08, 0x01, 0x80, 0x10, 0x0C, 0x00, 0x00, 0x30, 0x06, 0x00, 0x00, 0x60,
0x01, 0x80, 0x01, 0x80, 0x00, 0xE0, 0x07, 0x00, 0x00, 0x3F, 0xFC, 0x00, 0x00, 0x00, 0x00, 0x00
};
static const unsigned char PROGMEM sd [] = {
0x0F, 0xFF, 0xFF, 0xFE, 0x1F, 0xFF, 0xFF, 0xFF, 0x1F, 0xFE, 0x7C, 0xFF, 0x1B, 0x36, 0x6C, 0x9B,
0x19, 0x26, 0x4C, 0x93, 0x19, 0x26, 0x4C, 0x93, 0x19, 0x26, 0x4C, 0x93, 0x19, 0x26, 0x4C, 0x93,
0x19, 0x26, 0x4C, 0x93, 0x19, 0x26, 0x4C, 0x93, 0x19, 0x26, 0x4C, 0x93, 0x1F, 0xFF, 0xFF, 0xFF,
0x1F, 0xFF, 0xFF, 0xFF, 0x1F, 0xFF, 0xFF, 0xFF, 0x1F, 0xFF, 0xFF, 0xFF, 0x1F, 0xFF, 0xFF, 0xFF,
0x3F, 0xFF, 0xFF, 0xFF, 0x7F, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFC, 0xC7, 0xFF, 0xFF, 0xF9, 0x41, 0xFF, 0x1F, 0xF9, 0xDD, 0xFF,
0x1F, 0xFC, 0xDD, 0xFF, 0x1F, 0xFE, 0x5D, 0xFF, 0x1F, 0xF8, 0x43, 0xFF, 0x1F, 0xFD, 0xFF, 0xFF,
0x3F, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFE
};

// Define the integrated button pin on the XIAO Expansion board.
#define button D1
// Define the button state and the duration to utilize the integrated button in two different modes: long press and short press.
int button_state = 0;
#define DURATION 5000

// Define the data holders:
float temperature, m_temperature, humidity, pressure, weight;
int class_number = 0;
long timer;
uint16_t error;
char errorMessage[256];
 
void setup(){
  Serial.begin(115200);

  pinMode(button, INPUT_PULLUP);
  
  // Initialize the SSD1306 screen:
  display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
  display.display();
  delay(1000);

  display.clearDisplay();      
  display.setTextColor(SSD1306_BLACK, SSD1306_WHITE);
  display.setCursor(0,0);
  display.setTextSize(1);
  display.println("\nIoT AI-driven\n");
  display.setTextSize(3);
  display.println("Yogurt");
  display.setTextSize(1);
  display.println("\nProcessing");
  display.display();

  // Initialize the DS18B20 sensor.
  DS18B20.begin();

  // Define the required settings to initialize the Grove - Temperature & Humidity Sensor.
  sht4x.begin(Wire);
  uint32_t serialNumber;
  error = sht4x.serialNumber(serialNumber);

  // Check the Grove - Temperature & Humidity Sensor connection status and print the error message on the serial monitor, if any.
  if(error){
    Serial.print("Error: Grove - Temperature & Humidity Sensor not initialized!\n");
    errorToString(error, errorMessage, 256);
    Serial.println(errorMessage);
    err_msg();
  }else{
    Serial.print("Grove - Temperature & Humidity Sensor successfully initialized: "); Serial.println(serialNumber);
  }

  // Check the connection status between the weight (HX711) sensor and XIAO ESP32C3.
  while (!MyScale.begin()) {
    Serial.println("Error: HX711 initialization is failed!");
    err_msg();
    delay(1000);
  }
  Serial.println("HX711 initialization is successful!");
  
  // Set the calibration weight (g) to calibrate the weight sensor automatically.
  MyScale.setCalWeight(100);
  // Set the calibration threshold (g).
  MyScale.setThreshold(30);
  // Display the current calibration value. 
  Serial.print("\nCalibration Value: "); Serial.println(MyScale.getCalibration());
  MyScale.setCalibration(MyScale.getCalibration());
  delay(1000);
  
  // Check the connection status between XIAO ESP32C3 and the SD card.
  if(!SD.begin()){
    Serial.println("Error: SD card initialization failed!\n");
    err_msg();
    while (1);
  }
  Serial.println("SD card is detected successfully!\n");

  delay(5000);    
 
}
 
void loop(){
  get_temperature_and_humidity();
  get_pressure();
  get_weight(15);
  get_milk_temperature();
  
  // Show the collected data on the screen.
  home_screen();

  // Detect the long press and short press button modes:
  button_state = 0;
  if(!digitalRead(button)){
    timer = millis();
    button_state = 1;
    while((millis()-timer) <= DURATION){
      if(digitalRead(button)){
        button_state = 2;
        break;
      }
    }
  }
  
  if(button_state == 1){
    // Save the given data record to the given CSV file on the SD card when long-pressed.
    save_data_to_SD_Card(SD, class_number);
  }else if(button_state == 2){
    // Change the class number when short-pressed.
    class_number++;
    if(class_number > 2) class_number = 0;
    Serial.println("\n\nSelected Class: " + String(class_number) + "\n");
  }

}

void save_data_to_SD_Card(fs::FS &fs, int consistency_level){
  // Open the given CSV file on the SD card in the APPEND file mode.
  // FILE MODES: WRITE, READ, APPEND
  myFile = fs.open(data_file, FILE_APPEND);
  delay(1000);
  // If the given file is opened successfully:
  if(myFile){
    Serial.print("\n\nWriting to "); Serial.print(data_file); Serial.println("...");
    // Create the data record to be inserted as a new row: 
    String data_record = String(temperature) + "," + String(humidity) + "," + String(pressure) + "," + String(m_temperature) + "," + String(weight) + ',' + String(consistency_level);
    // Append the data record:
    myFile.println(data_record);
    // Close the CSV file:
    myFile.close();
    Serial.println("Data saved successfully!\n");
    // Notify the user after appending the given data record successfully.
    display.clearDisplay(); 
    display.drawBitmap(48, 0, sd, 32, 44, SSD1306_WHITE);
    display.setTextSize(1);
    display.setTextColor(SSD1306_WHITE);  
    display.setCursor(0,48); 
    display.println("Data saved to the SD card!");
    display.display();  
  }else{
    // If XIAO ESP32C3 cannot open the given CSV file successfully:
    Serial.println("\nXIAO ESP32C3 cannot open the given CSV file successfully!\n");
    err_msg();
  }
  // Exit and clear:
  delay(4000);
}

void get_temperature_and_humidity(){
  // Obtain the measurements generated by the Grove - Temperature & Humidity Sensor.
  error = sht4x.measureHighPrecision(temperature, humidity);
  if(error){
    Serial.print("Error trying to execute measureHighPrecision(): ");
    errorToString(error, errorMessage, 256);
    Serial.println(errorMessage);
  }else{
    Serial.print("\nTemperature : "); Serial.print(temperature); Serial.println("C");
    Serial.print("Humidity : "); Serial.print(humidity); Serial.println("%");
  }
  delay(500);
}

void get_pressure(){
  // Obtain the measurements generated by the Grove - Integrated Pressure Sensor.
  rawValue = 0;
  // Convert the accumulation of raw data to the pressure estimation.
  for (int x = 0; x < 10; x++) rawValue = rawValue + analogRead(pressure_s_pin);
  pressure = (rawValue - offset) * 700.0 / (fullScale - offset);
  Serial.print("\nPressure : "); Serial.print(pressure); Serial.println(" kPa");
}

void get_weight(int calibration){
  weight = MyScale.readWeight();
  weight = weight - calibration;
  if(weight < 0.5) weight = 0;
  Serial.print("\nWeight: "); Serial.print(weight); Serial.println(" g");
  delay(500);
}

void get_milk_temperature(){
  // Obtain the temperature measurement generated by the DS18B20 Waterproof Temperature Sensor.
  DS18B20.requestTemperatures(); 
  m_temperature = DS18B20.getTempCByIndex(0);
  Serial.print("\nMilk Temperature: "); Serial.print(m_temperature); Serial.println("C");
}

void home_screen(){
  display.clearDisplay();   
  display.setTextSize(1); 
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0,0);
  display.println("Temp => " + String(temperature) + " *C");
  display.println("Humidity => " + String(humidity) + " %");
  display.println("Pres. => " + String(pressure) + " kPa");
  display.println();
  display.println("M_Temp => " + String(m_temperature) + " *C");
  display.println("Weight => " + String(weight) + " g");
  display.println();
  display.println("Selected Class => " + String(class_number));
  display.display();  
}

void err_msg(){
  // Show the error message on the SSD1306 screen.
  display.clearDisplay();   
  display.drawBitmap(48, 0, _error, 32, 32, SSD1306_WHITE);
  display.setTextSize(1); 
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0,40); 
  display.println("Check the serial monitor to see the error!");
  display.display();  
}

AI_yogurt_processing_run_model.ino

Arduino
         /////////////////////////////////////////////  
        //    IoT AI-driven Yogurt Processing      //
       //      & Texture Prediction w/ Blynk      //
      //             ---------------             //
     //             (XIAO ESP32C3)              //           
    //             by Kutluhan Aktar           // 
   //                                         //
  /////////////////////////////////////////////

//
// Collect environmental factors and the culture amount while producing yogurt. Then, run a neural network model via Blynk to predict its texture.
//
// For more information:
// https://www.theamplituhedron.com/projects/IoT_AI_driven_Yogurt_Processing_Texture_Prediction
//
//
// Connections
// XIAO ESP32C3 :  
//                                Grove - Temperature & Humidity Sensor
// A4   --------------------------- SDA
// A5   --------------------------- SCL
//                                Grove - Integrated Pressure Sensor
// A0   --------------------------- S
//                                Gravity: I2C 1Kg Weight Sensor Kit - HX711
// A4   --------------------------- SDA
// A5   --------------------------- SCL
//                                DS18B20 Waterproof Temperature Sensor
// D6   --------------------------- Data
//                                SSD1306 OLED Display (128x64)
// A4   --------------------------- SDA
// A5   --------------------------- SCL
//                                MicroSD Card Module (Built-in on the XIAO Expansion board)
// D10  --------------------------- MOSI
// D9   --------------------------- MISO
// D8   --------------------------- CLK (SCK)
// D2   --------------------------- CS (SS)  
//                                Button (Built-in on the XIAO Expansion board)
// D1   --------------------------- +


// Define the Template ID, Device Name, and Auth Token parameters provided by the Blynk.Cloud.
#define BLYNK_TEMPLATE_ID "<_TEMPLATE_ID_>"
#define BLYNK_DEVICE_NAME "<_DEVICE_NAME_>"
#define BLYNK_AUTH_TOKEN "<_AUTH_TOKEN_>"

// Uncomment the line below to activate debugging for the Blynk application.
//#define BLYNK_PRINT Serial

// Include the required libraries:
#include <WiFi.h>
#include <WiFiClient.h>
#include <BlynkSimpleEsp32.h>
#include <SPI.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <SensirionI2CSht4x.h>
#include <DFRobot_HX711_I2C.h>
#include <OneWire.h>
#include <DallasTemperature.h>

char ssid[] = "<_SSID_>";    // your network SSID (name)
char pass[] = "<_PASS_>";    // your network password (use for WPA, or use as key for WEP)

// Define the required variables for the Blynk application and the virtual pins connected to the dashboard widgets.
char auth[] = BLYNK_AUTH_TOKEN;
#define TEMP_WIDGET     V4
#define HUMD_WIDGET     V12
#define PRES_WIDGET     V6
#define M_TEMP_WIDGET   V7
#define WEIGHT_WIDGET   V8
#define BUTTON_WIDGET   V9
#define LABEL_WIDGET    V10

// Include the Edge Impulse model converted to an Arduino library:
#include <IoT_AI-driven_Yogurt_Processing_inferencing.h>

// Define the required parameters to run an inference with the Edge Impulse model.
#define FREQUENCY_HZ        EI_CLASSIFIER_FREQUENCY
#define INTERVAL_MS         (1000 / (FREQUENCY_HZ + 1))

// Define the features array to classify one frame of data.
float features[EI_CLASSIFIER_DSP_INPUT_FRAME_SIZE];
size_t feature_ix = 0;

// Define the threshold value for the model outputs (predictions).
float threshold = 0.60;

// Define the yogurt consistency level (class) names:
String classes[] = {"Thinner", "Optimum", "Curdling"};

// Define the 0.96 OLED display (SSD1306) on the XIAO Expansion board. 
#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels
#define OLED_RESET    -1 // Reset pin # (or -1 if sharing Arduino reset pin)

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

// Define the Grove - Temperature & Humidity Sensor object.
SensirionI2CSht4x sht4x;

// Define the HX711 weight sensor.
DFRobot_HX711_I2C MyScale;

// Define the DS18B20 waterproof temperature sensor settings:
#define ONE_WIRE_BUS D6
OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature DS18B20(&oneWire);

// Define minimum and maximum pressure thresholds for the Grove - Integrated Pressure Sensor depending on the initial sensor measurements.
#define pressure_s_pin A0
int rawValue;
int offset = 221; // minimum (adjust)
int fullScale = 8360; // maximum (adjust)
 
// Define monochrome graphics:
static const unsigned char PROGMEM _error [] = {
0x00, 0x00, 0x00, 0x00, 0x00, 0x3F, 0xFC, 0x00, 0x00, 0xE0, 0x07, 0x00, 0x01, 0x80, 0x01, 0x80,
0x06, 0x00, 0x00, 0x60, 0x0C, 0x00, 0x00, 0x30, 0x08, 0x01, 0x80, 0x10, 0x10, 0x03, 0xC0, 0x08,
0x30, 0x02, 0x40, 0x0C, 0x20, 0x02, 0x40, 0x04, 0x60, 0x02, 0x40, 0x06, 0x40, 0x02, 0x40, 0x02,
0x40, 0x02, 0x40, 0x02, 0x40, 0x02, 0x40, 0x02, 0x40, 0x02, 0x40, 0x02, 0x40, 0x02, 0x40, 0x02,
0x40, 0x02, 0x40, 0x02, 0x40, 0x02, 0x40, 0x02, 0x40, 0x03, 0xC0, 0x02, 0x40, 0x01, 0x80, 0x02,
0x40, 0x00, 0x00, 0x02, 0x60, 0x00, 0x00, 0x06, 0x20, 0x01, 0x80, 0x04, 0x30, 0x03, 0xC0, 0x0C,
0x10, 0x03, 0xC0, 0x08, 0x08, 0x01, 0x80, 0x10, 0x0C, 0x00, 0x00, 0x30, 0x06, 0x00, 0x00, 0x60,
0x01, 0x80, 0x01, 0x80, 0x00, 0xE0, 0x07, 0x00, 0x00, 0x3F, 0xFC, 0x00, 0x00, 0x00, 0x00, 0x00
};
static const unsigned char PROGMEM thinner [] = {
0x00, 0x00, 0x00, 0x00, 0x0F, 0xFE, 0x00, 0x00, 0x0F, 0xFF, 0x00, 0x00, 0x07, 0xFE, 0x00, 0x00,
0x08, 0x03, 0x00, 0x00, 0x18, 0x01, 0x80, 0x00, 0x30, 0x00, 0x80, 0x00, 0x20, 0x00, 0xC0, 0x00,
0x60, 0x00, 0x60, 0x00, 0x40, 0x3F, 0xE0, 0x00, 0x79, 0xFF, 0xE0, 0x00, 0x7F, 0xFF, 0xE0, 0x00,
0x7F, 0xFF, 0xE0, 0x00, 0x7F, 0xFF, 0xE0, 0x00, 0x7F, 0xFF, 0xE0, 0x00, 0x7F, 0xFF, 0xE0, 0x00,
0x7F, 0xFF, 0xE0, 0x00, 0x7F, 0xFF, 0xE0, 0x00, 0x7F, 0xFF, 0xE0, 0x00, 0x7F, 0xFF, 0xE0, 0x00,
0x7F, 0xFF, 0xEF, 0xFE, 0x7F, 0xFF, 0xE8, 0x02, 0x7F, 0xFF, 0xE8, 0x02, 0x7F, 0xFF, 0xE8, 0x12,
0x7F, 0xFF, 0xEF, 0xFE, 0x7F, 0xFF, 0xEF, 0xFE, 0x7F, 0xFF, 0xEF, 0xFE, 0x7F, 0xFF, 0xEF, 0xFE,
0x7F, 0xFF, 0xE7, 0xFC, 0x7F, 0xFF, 0xE7, 0xFC, 0x7F, 0xFF, 0xE7, 0xFC, 0x3F, 0xFF, 0xC7, 0xFC
};
static const unsigned char PROGMEM optimum [] = {
0x00, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xE0, 0x0F, 0x80, 0x00, 0x3C, 0x38, 0x00, 0x70, 0x06,
0x61, 0xEC, 0xFF, 0xE2, 0xC7, 0x13, 0x98, 0x3B, 0xD8, 0x00, 0x0F, 0x06, 0x70, 0x1E, 0x3B, 0x9E,
0x7F, 0x80, 0x01, 0xFE, 0x2F, 0xFF, 0xFF, 0xFC, 0x21, 0xFF, 0xFF, 0xC4, 0x20, 0x0F, 0xFC, 0x04,
0x20, 0x18, 0x03, 0x04, 0x10, 0x60, 0x01, 0x84, 0x10, 0xC0, 0x00, 0xC4, 0x11, 0x00, 0x00, 0x44,
0x1E, 0x00, 0x00, 0x68, 0x13, 0x20, 0x01, 0xF8, 0x1F, 0x79, 0x0E, 0xA8, 0x0C, 0xFB, 0xDA, 0x98,
0x0C, 0xA6, 0x56, 0x98, 0x0C, 0xAF, 0xD6, 0x58, 0x0A, 0xAE, 0xD6, 0x78, 0x0A, 0x93, 0xF0, 0x30,
0x0E, 0x00, 0x00, 0x30, 0x0D, 0x00, 0x00, 0x70, 0x04, 0x80, 0x00, 0xD0, 0x04, 0x60, 0x01, 0x90,
0x02, 0x38, 0x06, 0x30, 0x01, 0xCF, 0xF9, 0xC0, 0x00, 0x7F, 0xFF, 0x00, 0x00, 0x00, 0xC0, 0x00
};
static const unsigned char PROGMEM curdling [] = {
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0E, 0x00, 0x00, 0x00, 0x3F, 0x00, 0x00, 0x00, 0x7F, 0x00,
0x00, 0x01, 0xE3, 0x00, 0x00, 0x03, 0xC3, 0x80, 0x00, 0x0F, 0xC7, 0xC0, 0x00, 0x0F, 0xFF, 0xF8,
0x00, 0x0F, 0xFF, 0xFC, 0x00, 0x1F, 0xFF, 0xFC, 0x00, 0x3F, 0xFF, 0xFC, 0x07, 0xFF, 0x0F, 0xFC,
0x1F, 0xFE, 0x0F, 0xFE, 0x3F, 0xFC, 0x07, 0xFC, 0x00, 0x00, 0x00, 0x00, 0x7F, 0xFE, 0x0F, 0xFE,
0x7F, 0xFE, 0x1F, 0xFE, 0x7F, 0xFF, 0x3F, 0xFE, 0x7F, 0xFF, 0xFF, 0x3E, 0x7F, 0x1F, 0xFF, 0x3E,
0x7F, 0x0F, 0xFF, 0x3E, 0x1F, 0x0F, 0xFF, 0xFE, 0x1F, 0x0F, 0xFF, 0xFE, 0x0F, 0x0F, 0xFF, 0xFE,
0x0F, 0x9F, 0xDF, 0xFE, 0x0F, 0xFF, 0x8F, 0xFE, 0x1F, 0xFF, 0x8F, 0xFE, 0x3F, 0xFF, 0xCF, 0xFE,
0x7F, 0xFF, 0xFF, 0xFE, 0x7F, 0xFF, 0xFF, 0xFE, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};

// Create an array including icons for labels (classes).
static const unsigned char PROGMEM *class_icons[] = {thinner, optimum, curdling};

// Define the data holders:
float temperature, m_temperature, humidity, pressure, weight;
long timer;
int predicted_class = -1;
volatile boolean model_running = false;
uint16_t error;
char errorMessage[256];

void setup(){
  Serial.begin(115200);

  // Create the Blynk object.
  Blynk.begin(auth, ssid, pass);
  
  // Initialize the SSD1306 screen:
  display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
  display.display();
  delay(1000);

  display.clearDisplay();      
  display.setTextColor(SSD1306_BLACK, SSD1306_WHITE);
  display.setCursor(0,0);
  display.setTextSize(1);
  display.println("\nIoT AI-driven\n");
  display.setTextSize(3);
  display.println("Yogurt");
  display.setTextSize(1);
  display.println("\nProcessing");
  display.display();

  // Initialize the DS18B20 sensor.
  DS18B20.begin();

  // Define the required settings to initialize the Grove - Temperature & Humidity Sensor.
  sht4x.begin(Wire);
  uint32_t serialNumber;
  error = sht4x.serialNumber(serialNumber);

  // Check the Grove - Temperature & Humidity Sensor connection status and print the error message on the serial monitor, if any.
  if(error){
    Serial.print("Error: Grove - Temperature & Humidity Sensor not initialized!\n");
    errorToString(error, errorMessage, 256);
    Serial.println(errorMessage);
    err_msg();
  }else{
    Serial.print("Grove - Temperature & Humidity Sensor successfully initialized: "); Serial.println(serialNumber);
  }

  // Check the connection status between the weight (HX711) sensor and XIAO ESP32C3.
  while (!MyScale.begin()) {
    Serial.println("Error: HX711 initialization is failed!");
    err_msg();
    delay(1000);
  }
  Serial.println("HX711 initialization is successful!");
  
  // Set the calibration weight (g) to calibrate the weight sensor automatically.
  MyScale.setCalWeight(100);
  // Set the calibration threshold (g).
  MyScale.setThreshold(30);
  // Display the current calibration value. 
  Serial.print("\nCalibration Value: "); Serial.println(MyScale.getCalibration());
  MyScale.setCalibration(MyScale.getCalibration());
  delay(1000);
}
 
void loop(){
  // Initiate the communication between the Blynk dashboard and XIAO ESP32C3.
  Blynk.run();
  
  get_temperature_and_humidity();
  get_pressure();
  get_weight(15);
  get_milk_temperature();
  
  // Show the collected data on the screen.
  home_screen();

  // If the switch widget on the Blynk dashboard is activated, run the Edge Impulse model to make predictions on the yogurt consistency levels (classes).
  if(model_running){ run_inference_to_make_predictions(1); model_running = false; }

  // If the Edge Impulse model predicts a yogurt consistency level (class) successfully:
  if(predicted_class != -1){
      // Transfer the predicted label (class) to the Blynk application (dashboard).
      Blynk.virtualWrite(LABEL_WIDGET, classes[predicted_class]);
      // Print the predicted label (class) on the built-in screen.
      display.clearDisplay();
      display.drawBitmap(48, 0, class_icons[predicted_class], 32, 32, SSD1306_WHITE);
      display.setTextSize(1); 
      display.setTextColor(SSD1306_WHITE);
      display.setCursor(0,40);
      display.println("Transferred to Blynk");
      String c = "Class: " + classes[predicted_class];
      int str_x = c.length() * 6;
      display.setCursor((SCREEN_WIDTH - str_x) / 2, 56);
      display.println(c);
      display.display();
      // Clear the predicted label (class).
      predicted_class = -1;
      delay(1000);
  }

  // Every 30 seconds, transfer the collected environmental factors and culture amount to the Blynk application so as to update the assigned widgets on the Blynk dashboard.
  if(millis() - timer >= 30*1000){ update_Blynk_parameters(); Serial.println("\n\nBlynk Dashboard: Data Transferred Successfully!\n"); timer = millis(); }
}

void run_inference_to_make_predictions(int multiply){
  // Scale (normalize) data items depending on the given model:
  float scaled_temperature = temperature / 100;
  float scaled_humidity = humidity / 100;
  float scaled_pressure = pressure / 1000;
  float scaled_milk_temperature = m_temperature / 100;
  float scaled_starter_weight = weight / 10;

  // Copy the scaled data items to the features buffer.
  // If required, multiply the scaled data items while copying them to the features buffer.
  for(int i=0; i<multiply; i++){  
    features[feature_ix++] = scaled_temperature;
    features[feature_ix++] = scaled_humidity;
    features[feature_ix++] = scaled_pressure;
    features[feature_ix++] = scaled_milk_temperature;
    features[feature_ix++] = scaled_starter_weight;
  }

  // Display the progress of copying data to the features buffer.
  Serial.print("Features Buffer Progress: "); Serial.print(feature_ix); Serial.print(" / "); Serial.println(EI_CLASSIFIER_DSP_INPUT_FRAME_SIZE);
  
  // Run inference:
  if(feature_ix == EI_CLASSIFIER_DSP_INPUT_FRAME_SIZE){    
    ei_impulse_result_t result;
    // Create a signal object from the features buffer (frame).
    signal_t signal;
    numpy::signal_from_buffer(features, EI_CLASSIFIER_DSP_INPUT_FRAME_SIZE, &signal);
    // Run the classifier:
    EI_IMPULSE_ERROR res = run_classifier(&signal, &result, false);
    ei_printf("\nrun_classifier returned: %d\n", res);
    if(res != 0) return;

    // Print the inference timings on the serial monitor.
    ei_printf("Predictions (DSP: %d ms., Classification: %d ms., Anomaly: %d ms.): \n", 
        result.timing.dsp, result.timing.classification, result.timing.anomaly);

    // Obtain the prediction results for each label (class).
    for(size_t ix = 0; ix < EI_CLASSIFIER_LABEL_COUNT; ix++){
      // Print the prediction results on the serial monitor.
      ei_printf("%s:\t%.5f\n", result.classification[ix].label, result.classification[ix].value);
      // Get the predicted label (class).
      if(result.classification[ix].value >= threshold) predicted_class = ix;
    }
    Serial.print("\nPredicted Class: "); Serial.println(predicted_class);

    // Detect anomalies, if any:
    #if EI_CLASSIFIER_HAS_ANOMALY == 1
      ei_printf("Anomaly : \t%.3f\n", result.anomaly);
    #endif

    // Clear the features buffer (frame):
    feature_ix = 0;
  }
}

void update_Blynk_parameters(){
  // Transfer the collected yogurt processing information to the Blynk dashboard.
  Blynk.virtualWrite(TEMP_WIDGET, temperature);
  Blynk.virtualWrite(HUMD_WIDGET, humidity);
  Blynk.virtualWrite(PRES_WIDGET, pressure);
  Blynk.virtualWrite(M_TEMP_WIDGET, m_temperature);
  Blynk.virtualWrite(WEIGHT_WIDGET, weight);
}

// Obtain the incoming value from the switch (button) widget on the Blynk dashboard.
BLYNK_WRITE(BUTTON_WIDGET){
  int buttonValue = param.asInt();
  if(buttonValue){ model_running = true; }
  else{ Blynk.virtualWrite(LABEL_WIDGET, "Waiting..."); }
}

void get_temperature_and_humidity(){
  // Obtain the measurements generated by the Grove - Temperature & Humidity Sensor.
  error = sht4x.measureHighPrecision(temperature, humidity);
  if(error){
    Serial.print("Error trying to execute measureHighPrecision(): ");
    errorToString(error, errorMessage, 256);
    Serial.println(errorMessage);
  }else{
    Serial.print("\nTemperature : "); Serial.print(temperature); Serial.println("C");
    Serial.print("Humidity : "); Serial.print(humidity); Serial.println("%");
  }
  delay(500);
}

void get_pressure(){
  // Obtain the measurements generated by the Grove - Integrated Pressure Sensor.
  rawValue = 0;
  // Convert the accumulation of raw data to the pressure estimation.
  for (int x = 0; x < 10; x++) rawValue = rawValue + analogRead(pressure_s_pin);
  pressure = (rawValue - offset) * 700.0 / (fullScale - offset);
  Serial.print("\nPressure : "); Serial.print(pressure); Serial.println(" kPa");
}

void get_weight(int calibration){
  weight = MyScale.readWeight();
  weight = weight - calibration;
  if(weight < 0.5) weight = 0;
  Serial.print("\nWeight: "); Serial.print(weight); Serial.println(" g");
  delay(500);
}

void get_milk_temperature(){
  // Obtain the temperature measurement generated by the DS18B20 Waterproof Temperature Sensor.
  DS18B20.requestTemperatures(); 
  m_temperature = DS18B20.getTempCByIndex(0);
  Serial.print("\nMilk Temperature: "); Serial.print(m_temperature); Serial.println("C");
}

void home_screen(){
  display.clearDisplay();   
  display.setTextSize(1); 
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0,0);
  display.println("Temp => " + String(temperature) + " *C");
  display.println("Humidity => " + String(humidity) + " %");
  display.println("Pres. => " + String(pressure) + " kPa");
  display.println();
  display.println("M_Temp => " + String(m_temperature) + " *C");
  display.println("Weight => " + String(weight) + " g");
  display.display();  
}

void err_msg(){
  // Show the error message on the SSD1306 screen.
  display.clearDisplay();   
  display.drawBitmap(48, 0, _error, 32, 32, SSD1306_WHITE);
  display.setTextSize(1); 
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0,40); 
  display.println("Check the serial monitor to see the error!");
  display.display();  
}

process_dataset.py

Python
# IoT AI-driven Yogurt Processing & Texture Prediction w/ Blynk
#
# Windows, Linux, or Ubuntu
#
# By Kutluhan Aktar
#
# Collect environmental factors and culture amount while processing yogurt. 
# Then, run a neural network model via Blynk to predict its texture.
#
#
# For more information:
# https://www.theamplituhedron.com/projects/IoT_AI_driven_Yogurt_Processing_Texture_Prediction

import numpy as np
import pandas as pd
from csv import writer

# Create a class to modify the given data set so as to upload properly formatted samples to Edge Impulse.
class process_dataset:
    def __init__(self, csv_path):
        # Read the data set from the given CSV file.
        self.df = pd.read_csv(csv_path)
        # Define the class (label) names.
        self.class_names = ["Thinner", "Optimum", "Curdling"]
    # Scale (normalize) data to define appropriately formatted inputs.
    def scale_data_elements(self):
        self.df["scaled_temperature"] = self.df["temperature"] / 100
        self.df["scaled_humidity"] = self.df["humidity"] / 100
        self.df["scaled_pressure"] = self.df["pressure"] / 1000
        self.df["scaled_milk_temperature"] = self.df["milk_temperature"] / 100
        self.df["scaled_starter_weight"] = self.df["starter_weight"] / 10
        print("Data Elements Scaled Successfully!")
    # Split the data set to generate a separate CSV file for each data record.    
    def split_dataset_by_labels(self, class_number):
        l = len(self.df)
        sample_number = 0
        # Split the data set according to the yogurt consistency levels (classes):
        for i in range(l):
            # Add the header as the first row:
            processed_data = [["temperature", "humidity", "pressure", "milk_temperature", "starter_weight"]]
            if(self.df["consistency_level"][i] == class_number):
                row = [self.df["scaled_temperature"][i], self.df["scaled_humidity"][i], self.df["scaled_pressure"][i], self.df["scaled_milk_temperature"][i], self.df["scaled_starter_weight"][i]]
                processed_data.append(row)
                # Increment the sample number:   
                sample_number+=1   
                # Create a CSV file for each data record, identified with the sample number.
                filename = "data/{}.sample_{}.csv".format(self.class_names[class_number], sample_number)
                with open(filename, "a", newline="") as f:
                    for r in range(len(processed_data)):
                        writer(f).writerow(processed_data[r])
                    f.close()
                print("CSV File Successfully Created: " + filename)
        
# Define a new class object named 'dataset':
dataset = process_dataset("yogurt_data.csv")

# Scale data and generate a separate CSV file for each sample:
dataset.scale_data_elements()
for c in range(len(dataset.class_names)):
    dataset.split_dataset_by_labels(c)
            

Credits

Kutluhan Aktar
82 projects • 312 followers
AI & Full-Stack Developer | @EdgeImpulse | @Particle | Maker | Independent Researcher

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