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Kutluhan Aktar
Published © CC BY

BLE AI-driven Smartwatch Detecting Potential Sun Damage

Log UV & weather data on an SD card to train an Edge Impulse model. Then, run it to get informed of sun damage over BLE via an Android app.

ExpertFull instructions provided4,000

Things used in this project

Hardware components

XIAO BLE
Seeed Studio XIAO BLE
nRF52840
×1
Seeeduino XIAO Expansion board
Seeed Studio Seeeduino XIAO Expansion board
×1
Seeed Studio Grove - UV Sensor
×1
BMP180 Precision Sensor
×1
Keyes 10mm RGB LED Module (140C05)
×1
Creality CR-6 SE 3D Printer
×1
Flash Memory Card, MicroSD Card
Flash Memory Card, MicroSD Card
×1
3.7V LiPo Battery
×1
15mm Wide Yellow Velcro
×1
10mm M3 Male-Female Brass Hex Spacer Standoff
×4
M3 Screw and Hex Nut
×4
Jumper wires (generic)
Jumper wires (generic)
×1

Software apps and online services

Edge Impulse Studio
Edge Impulse Studio
Arduino IDE
Arduino IDE
Thonny
Fusion
Autodesk Fusion
Ultimaker Cura
MIT App Inventor 2
MIT App Inventor 2

Hand tools and fabrication machines

Hot glue gun (generic)
Hot glue gun (generic)
Soldering iron (generic)
Soldering iron (generic)

Story

Read more

Custom parts and enclosures

BLE_Smartwatch_Case_v1.stl

BLE_Smartwatch_Case_Sliding_Cover_v1.stl

Edge Impulse Model (Arduino Library)

BLE_UV_Smartwatch.aia

Schematics

Schematic-1

Schematic-2

Code

process_dataset.py

Python
# BLE AI-driven Smartwatch Detecting Potential Sun Damage w/ Edge Impulse
#
# Windows, Linux, or Ubuntu
#
# By Kutluhan Aktar
#
# Log UV & weather data on an SD card to train an Edge Impulse model. Then, run it to get informed of sun damage over BLE via an Android app.
# 
#
# For more information:
# https://www.theamplituhedron.com/projects/BLE_AI_driven_Smartwatch_Detecting_Potential_Sun_Damage_w_Edge_Impulse

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 = ["Tolerable", "Risky", "Perilous"]
    # Scale (normalize) data to define appropriately formatted inputs.
    def scale_data_elements(self):
        self.df["scaled_uv_index"] = self.df["uv_index"] / 10
        self.df["scaled_temperature"] = self.df["temperature"] / 100
        self.df["scaled_pressure"] = self.df["pressure"] / 100000
        self.df["scaled_altitude"] = self.df["altitude"] / 100
        print("Data Elements Scaled Successfully!")
    # Split the data set to generate a separate CSV file for each sample.     
    def split_dataset_by_labels(self, class_number):
        l = len(self.df)
        sample_number = 0
        # Split the data set according to sun damage risk levels (classes):
        for i in range(l):
            # Add the header as the first row:
            processed_data = [["uv_index","temperature","pressure","altitude"]]
            if (self.df["risk_level"][i] == class_number):
                row = [self.df["scaled_uv_index"][i], self.df["scaled_temperature"][i], self.df["scaled_pressure"][i], self.df["scaled_altitude"][i]]
                processed_data.append(row)
                # Increase the sample number for each sample:   
                sample_number+=1   
                # Create a CSV file for each sample identified with the sample number.
                filename = "{}.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("UV_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)
            

BLE_smartwatch_data_collect.ino

Arduino
         /////////////////////////////////////////////  
        //   BLE AI-driven Smartwatch Detecting    //
       //   Potential Sun Damage w/ Edge Impulse  //
      //             ---------------             //
     //               (XIAO BLE)                //           
    //             by Kutluhan Aktar           // 
   //                                         //
  /////////////////////////////////////////////

//
// Log UV & weather data on an SD card to train an Edge Impulse model. Then, run it to get informed of sun damage over BLE via an Android app.
//
// For more information:
// https://www.theamplituhedron.com/projects/BLE_AI_driven_Smartwatch_Detecting_Potential_Sun_Damage_w_Edge_Impulse
//
//
// Connections
// XIAO BLE :  
//                                Grove - UV Sensor
// A0  --------------------------- SIG
//                                BMP180 Barometric Pressure/Temperature/Altitude Sensor
// A4  --------------------------- SDA
// A5  --------------------------- SCL
//                                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  
//                                Button (Built-in on the XIAO Expansion board)
// D1  --------------------------- +
//                                Keyes 10mm RGB LED Module (140C05)
// D7  --------------------------- R
// D3  --------------------------- G
// D6  --------------------------- B  


// Include the required libraries:
#include <SPI.h>
#include <SD.h>
#include <Adafruit_BMP085.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

// Define the BMP180 Barometric Pressure/Temperature/Altitude Sensor.
Adafruit_BMP085 bmp;

// Define the Grove  UV Sensor pin.
#define UV_pin A0

// Initialize the File class and define the chip select pin:
File myFile;
const int chip_select = 2;
// Define the CSV file name: 
const char* data_file = "UV_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 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 1
// 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 2000

// Define the RGB LED pins:
#define redPin     7
#define greenPin   3
#define bluePin    6

// Define the data holders:
int class_number = 0;
float _temperature, _altitude, _real_altitude;
int UV_index, _pressure, _sea_level_pressure;
long timer;
 
void setup(){
  Serial.begin(9600);
  // while(!Serial); // Uncomment for debugging.

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

  display.clearDisplay();   
  display.setTextSize(2); 
  display.setTextColor(SSD1306_BLACK, SSD1306_WHITE);
  display.setCursor(0,0);
  display.println("BLE");
  display.println("Smartwatch");
  display.setTextSize(1);
  display.println("\n\nw/ Android");
  display.println("& Edge Impulse");
  display.display();

  // Check the BMP180 Barometric Pressure/Temperature/Altitude Sensor connection status: 
  while(!bmp.begin()){
    Serial.println("BMP180 Barometric Pressure/Temperature/Altitude Sensor is not found!");
    err_msg();
    delay(1000);
  }
  Serial.println("\nBMP180 Barometric Pressure/Temperature/Altitude Sensor is connected successfully!\n");

  // Check the connection status between XIAO BLE and the SD card.
  if (!SD.begin(chip_select)){
    Serial.println("SD card initialization failed!\n");
    err_msg();
    while (1);
  }
  Serial.println("SD card is detected successfully!\n");
  adjustColor(0,0,255);
  delay(5000);  
}
 
void loop(){
  get_UV_radiation();
  delay(100);
  collect_BMP180_data();
  delay(500);

  // Show the collected data on the screen.
  home_screen();

  // Detect the long press and short press button modes:
  button_state = 0;
  if(!digitalRead(button)){
    adjustColor(255,255,255);
    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(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("Selected Class: " + String(class_number) + "\n");
  }

}
void save_data_to_SD_Card(int risk_level){
  // Open the given CSV file on the SD card in the WRITE file mode.
  // FILE MODES: WRITE, READ
  myFile = SD.open(data_file, FILE_WRITE);
  adjustColor(255,255,0);
  delay(1000);
  // If the given file is opened successfully:
  if(myFile){
    Serial.print("Writing to "); Serial.print(data_file); Serial.println("...");
    // Create the data record to be inserted as a new row: 
    String data_record = String(UV_index) + "," + String(_temperature)  + "," + String(_pressure)  + "," + String(_altitude) + "," + String(risk_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.
    adjustColor(0,255,0);
    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 BLE cannot open the given CSV file successfully:
    Serial.println("XIAO BLE cannot open the given CSV file successfully!\n");
    err_msg();
  }
  // Exit and clear:
  delay(4000);
}

void home_screen(){
  adjustColor(255,0,255);
  display.clearDisplay();   
  display.setTextSize(1); 
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0,8);
  display.println("Estimations:");
  display.println("UV Index => " + String(UV_index));
  display.println("Temp. => " + String(_temperature) + " *C");
  display.println("Pressure => " + String(_pressure) + " Pa");
  display.println("Altitude => " + String(_altitude) + " m");
  display.println();
  display.println("Selected Class => " + String(class_number));
  display.display();  
}

void get_UV_radiation(){
  int sensorValue;
  long sum = 0;
  // Get the summation of the latest UV sensor measurements.
  for(int i=0;i<1024;i++){
    sensorValue = analogRead(UV_pin);
    sum+=sensorValue;
    delay(2);
  }
  // Obtain the average sensor measurement to remove the glitch.
  long avr_val = sum/1024;
  // Estimate the UV index value with this formula roughly.
  UV_index = (avr_val*1000/4.3-83)/21;
  UV_index = UV_index / 1000;
  Serial.print("Estimated UV index value: "); Serial.println(UV_index); Serial.println();
  delay(20);
}

void collect_BMP180_data(){
  _temperature = bmp.readTemperature();
  _pressure = bmp.readPressure();
  // Calculate altitude assuming 'standard' barometric pressure of 1013.25 millibars (101325 Pascals).
  _altitude = bmp.readAltitude();
  _sea_level_pressure = bmp.readSealevelPressure();
  // To get a more precise altitude measurement, use the current sea level pressure, which will vary with the weather conditions. 
  _real_altitude = bmp.readAltitude(101500);
  // Print the data generated by the BMP180 Barometric Pressure/Temperature/Altitude Sensor.
  Serial.print("Temperature => "); Serial.print(_temperature); Serial.println(" *C");
  Serial.print("Pressure => "); Serial.print(_pressure); Serial.println(" Pa");
  Serial.print("Altitude => "); Serial.print(_altitude); Serial.println(" meters");
  Serial.print("Pressure at sea level (calculated) => "); Serial.print(_sea_level_pressure); Serial.println(" Pa");
  Serial.print("Real Altitude => "); Serial.print(_real_altitude); Serial.println(" meters\n");
}

void err_msg(){
  // Show the error message on the SSD1306 screen.
  adjustColor(255, 0, 0);
  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();  
}

void adjustColor(int r, int g, int b){
  analogWrite(redPin, (255-r));
  analogWrite(greenPin, (255-g));
  analogWrite(bluePin, (255-b));
}

BLE_smartwatch_run_model.ino

Arduino
         /////////////////////////////////////////////  
        //   BLE AI-driven Smartwatch Detecting    //
       //   Potential Sun Damage w/ Edge Impulse  //
      //             ---------------             //
     //               (XIAO BLE)                //           
    //             by Kutluhan Aktar           // 
   //                                         //
  /////////////////////////////////////////////

//
// Log UV & weather data on an SD card to train an Edge Impulse model. Then, run it to get informed of sun damage over BLE via an Android app.
//
// For more information:
// https://www.theamplituhedron.com/projects/BLE_AI_driven_Smartwatch_Detecting_Potential_Sun_Damage_w_Edge_Impulse
//
//
// Connections
// XIAO BLE :  
//                                Grove - UV Sensor
// A0  --------------------------- SIG
//                                BMP180 Barometric Pressure/Temperature/Altitude Sensor
// A4  --------------------------- SDA
// A5  --------------------------- SCL
//                                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  
//                                Button (Built-in on the XIAO Expansion board)
// D1  --------------------------- +
//                                Keyes 10mm RGB LED Module (140C05)
// D7  --------------------------- R
// D3  --------------------------- G
// D6  --------------------------- B  


// Include the required libraries:
#include <ArduinoBLE.h>
#include <Adafruit_BMP085.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

// Include the Edge Impulse model converted to an Arduino library:
#include <BLE_Smartwatch_Detecting_Potential_Sun_Damage_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 sun damage risk level (class) names and color codes:
String classes[] = {"Perilous", "Risky", "Tolerable"};
int color_codes[3][3] = {{255,0,0}, {255,255,0}, {0,255,0}};

// Create the BLE service:
BLEService BLE_smartwatch("19B10000-E8F2-537E-4F6C-D104768A1214");

// Create data characteristics and allow the remote device (central) to read and notify:
BLEFloatCharacteristic temperatureCharacteristic("19B10001-E8F2-537E-4F6C-D104768A1214", BLERead | BLENotify);
BLEFloatCharacteristic altitudeCharacteristic("19B10002-E8F2-537E-4F6C-D104768A1214", BLERead | BLENotify);
BLEFloatCharacteristic UVCharacteristic("19B10003-E8F2-537E-4F6C-D104768A1214", BLERead | BLENotify);
BLEFloatCharacteristic pressureCharacteristic("19B10004-E8F2-537E-4F6C-D104768A1214", BLERead | BLENotify);
BLEFloatCharacteristic classCharacteristic("19B10005-E8F2-537E-4F6C-D104768A1214", BLERead | BLENotify);

// Define the BMP180 Barometric Pressure/Temperature/Altitude Sensor.
Adafruit_BMP085 bmp;

// Define the Grove  UV Sensor pin.
#define UV_pin A0

// 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 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 tolerable [] = {
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x80, 0x00, 0x00, 0x01, 0x80, 0x00,
0x00, 0x01, 0x80, 0x00, 0x04, 0x03, 0xC0, 0x20, 0x03, 0x00, 0x00, 0xC0, 0x03, 0xC7, 0xE3, 0xC0,
0x01, 0x9F, 0xF9, 0x80, 0x01, 0x3F, 0xFC, 0x80, 0x00, 0x7F, 0xFE, 0x00, 0x00, 0xFF, 0xFF, 0x00,
0x00, 0xFF, 0xFF, 0x00, 0x01, 0xFF, 0xFF, 0x80, 0x05, 0xFF, 0xFF, 0xA0, 0x3D, 0xFF, 0xFF, 0xBC,
0x7D, 0xFF, 0xFF, 0xBE, 0x0D, 0xFF, 0xFF, 0xB0, 0x01, 0xFF, 0xFF, 0x80, 0x00, 0xFF, 0xFF, 0x00,
0x00, 0xFF, 0xFF, 0x00, 0x00, 0x7F, 0xFE, 0x00, 0x01, 0x3F, 0xFC, 0x80, 0x01, 0x9F, 0xF9, 0x80,
0x03, 0xC7, 0xE3, 0xC0, 0x03, 0x80, 0x01, 0xC0, 0x06, 0x03, 0xC0, 0x60, 0x00, 0x03, 0xC0, 0x00,
0x00, 0x01, 0x80, 0x00, 0x00, 0x01, 0x80, 0x00, 0x00, 0x01, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00
};
static const unsigned char PROGMEM risky [] = {
0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x80, 0x00, 0x00, 0x03, 0x80, 0x00, 0x02, 0x03, 0xC0, 0x00,
0x03, 0xC7, 0xE3, 0x80, 0x01, 0xE0, 0x07, 0x80, 0x01, 0xCF, 0xF3, 0x80, 0x01, 0x3F, 0xFC, 0x80,
0x00, 0x7F, 0xFE, 0x00, 0x00, 0xFF, 0xFF, 0x00, 0x1D, 0xFF, 0xFF, 0xB8, 0x7B, 0xFF, 0xFF, 0xDE,
0x3B, 0xFF, 0xFF, 0xDC, 0x1B, 0xFF, 0xFF, 0xD8, 0x0F, 0xFF, 0xFF, 0xF0, 0x07, 0xFF, 0xFF, 0xE0,
0x07, 0xFF, 0xFF, 0xE0, 0x1F, 0xFF, 0xFF, 0xF0, 0x1B, 0xFF, 0xFF, 0xD8, 0x3B, 0xFF, 0xFF, 0xDC,
0x7B, 0xFF, 0xFF, 0xDE, 0x0D, 0xFF, 0xFF, 0xB0, 0x00, 0xFF, 0xFF, 0x00, 0x01, 0x7F, 0xFE, 0x80,
0x01, 0x3F, 0xFD, 0x80, 0x01, 0xCF, 0xF3, 0x80, 0x01, 0xE0, 0x07, 0x80, 0x03, 0x87, 0xE1, 0x80,
0x00, 0x03, 0xC0, 0x00, 0x00, 0x01, 0x80, 0x00, 0x00, 0x01, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00
};
static const unsigned char PROGMEM perilous [] = {
0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x11, 0x88, 0x00, 0x00, 0x19, 0x98, 0x00,
0x01, 0x19, 0x98, 0x80, 0x00, 0x9D, 0xBB, 0x00, 0x00, 0xE3, 0x87, 0x00, 0x08, 0xDF, 0xF2, 0x30,
0x07, 0x3F, 0xFC, 0xE0, 0x03, 0x7F, 0xFE, 0xC0, 0x02, 0xFF, 0xFF, 0x00, 0x7D, 0xFF, 0xFF, 0x3C,
0x1D, 0xFF, 0xFF, 0xB8, 0x05, 0xFF, 0xFF, 0xA0, 0x03, 0xFF, 0xFF, 0x80, 0x7F, 0xFF, 0xFF, 0xBE,
0x1F, 0xFF, 0xFF, 0xB8, 0x03, 0xFF, 0xFF, 0x80, 0x0D, 0xFF, 0xFF, 0xB0, 0x1D, 0xFF, 0xFF, 0xB8,
0x60, 0xFF, 0xFF, 0x04, 0x02, 0xFF, 0xFE, 0x40, 0x07, 0x7F, 0xFE, 0xE0, 0x0E, 0x3F, 0xF8, 0x70,
0x18, 0xEF, 0xE7, 0x10, 0x00, 0xD8, 0x13, 0x00, 0x01, 0x9D, 0xB9, 0x80, 0x01, 0x19, 0x98, 0x80,
0x00, 0x11, 0x98, 0x00, 0x00, 0x11, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};

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

// Define the RGB LED pins:
#define redPin     7
#define greenPin   3
#define bluePin    6

// Define the data holders:
float _temperature, _altitude, _real_altitude;
int UV_index, _pressure, _sea_level_pressure;
long timer;
int predicted_class = -1;
 
void setup(){
  Serial.begin(9600);
  // while(!Serial); // Uncomment for debugging.

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

  display.clearDisplay();   
  display.setTextSize(2); 
  display.setTextColor(SSD1306_BLACK, SSD1306_WHITE);
  display.setCursor(0,0);
  display.println("BLE");
  display.println("Smartwatch");
  display.setTextSize(1);
  display.println("\n\nw/ Android");
  display.println("& Edge Impulse");
  display.display();

  // Check the BLE initialization status:
  while(!BLE.begin()){
    Serial.println("BLE initialization is failed!");
    err_msg();
  }
  Serial.println("\nBLE initialization is successful!\n");
  // Print this peripheral device's address information:
  Serial.print("MAC Address: "); Serial.println(BLE.address());
  Serial.print("Service UUID Address: "); Serial.println(BLE_smartwatch.uuid()); Serial.println();

  // Set the local name this peripheral advertises: 
  BLE.setLocalName("BLE UV Smartwatch");
  // Set the UUID for the service this peripheral advertises:
  BLE.setAdvertisedService(BLE_smartwatch);

  // Add the given data characteristics to the service:
  BLE_smartwatch.addCharacteristic(temperatureCharacteristic);
  BLE_smartwatch.addCharacteristic(altitudeCharacteristic);
  BLE_smartwatch.addCharacteristic(UVCharacteristic);
  BLE_smartwatch.addCharacteristic(pressureCharacteristic);
  BLE_smartwatch.addCharacteristic(classCharacteristic);

  // Add the service to the device:
  BLE.addService(BLE_smartwatch);

  // Assign event handlers for connected, disconnected devices to this peripheral:
  BLE.setEventHandler(BLEConnected, blePeripheralConnectHandler);
  BLE.setEventHandler(BLEDisconnected, blePeripheralDisconnectHandler);

  // Start advertising:
  BLE.advertise();
  Serial.println(("Bluetooth device active, waiting for connections..."));

  // Check the BMP180 Barometric Pressure/Temperature/Altitude Sensor connection status: 
  while(!bmp.begin()){
    Serial.println("BMP180 Barometric Pressure/Temperature/Altitude Sensor is not found!");
    err_msg();
    delay(1000);
  }
  Serial.println("\nBMP180 Barometric Pressure/Temperature/Altitude Sensor is connected successfully!\n");

  adjustColor(0,0,255);
  delay(5000);  
}
 
void loop(){
  get_UV_radiation();
  delay(100);
  collect_BMP180_data();
  delay(500);

  // Run inference:
  run_inference_to_make_predictions(10);

  // Every 30 seconds, advertise (transmit) the collected data and the predicted label (class) to the Android application over BLE.
  if(millis() - timer >= 30*1000){
    // If the Edge Impulse model predicted a label (class) successfully:
    if(predicted_class != -1){
      update_characteristics();
      // After updating characteristics, notify the user and print the predicted label (class) on the screen.
      display.clearDisplay();
      display.drawBitmap(48, 0, class_icons[predicted_class], 32, 32, SSD1306_WHITE);
      display.setTextSize(1); 
      display.setTextColor(SSD1306_WHITE);
      // Print:
      display.setCursor(0,40);
      display.println("BLE: Data Transmitted");
      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();
      adjustColor(color_codes[predicted_class][0], color_codes[predicted_class][1], color_codes[predicted_class][2]);
      delay(5000);
      // Clear the predicted label (class).
      predicted_class = -1;
    }
    // Update the timer:
    timer = millis();
  }
  
  // Show the collected data on the screen.
  home_screen();

  // Poll for BLE events:
  BLE.poll();
}

void run_inference_to_make_predictions(int multiply){
  // Scale (normalize) data items depending on the given model:
  float scaled_UV_index = UV_index / 10;
  float scaled_temperature = _temperature / 100;
  float scaled_pressure = _pressure / 100000;
  float scaled_altitude = _altitude / 100;

  // 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_UV_index;
    features[feature_ix++] = scaled_temperature;
    features[feature_ix++] = scaled_pressure;
    features[feature_ix++] = scaled_altitude;
  }

  // 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_characteristics(){
  // Update all data characteristics (floats):
  temperatureCharacteristic.writeValue(_temperature);
  altitudeCharacteristic.writeValue(_altitude);
  UVCharacteristic.writeValue(float(UV_index));
  pressureCharacteristic.writeValue(float(_pressure));
  classCharacteristic.writeValue(float(predicted_class));
  Serial.println("\n\nBLE: Data Characteristics Updated Successfully!\n");
}

void home_screen(){
  adjustColor(255,0,255);
  display.clearDisplay();   
  display.setTextSize(1); 
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0,8);
  display.println("Estimations:");
  display.println("UV Index => " + String(UV_index));
  display.println("Temp. => " + String(_temperature) + " *C");
  display.println("Pressure => " + String(_pressure) + " Pa");
  display.println("Altitude => " + String(_altitude) + " m");
  display.display();  
}

void get_UV_radiation(){
  int sensorValue;
  long sum = 0;
  // Get the summation of the latest UV sensor measurements.
  for(int i=0;i<1024;i++){
    sensorValue = analogRead(UV_pin);
    sum+=sensorValue;
    delay(2);
  }
  // Obtain the average sensor measurement to remove the glitch.
  long avr_val = sum/1024;
  // Estimate the UV index value with this formula roughly.
  UV_index = (avr_val*1000/4.3-83)/21;
  UV_index = UV_index / 1000;
  Serial.print("\nEstimated UV index value: "); Serial.println(UV_index);
  delay(20);
}

void collect_BMP180_data(){
  _temperature = bmp.readTemperature();
  _pressure = bmp.readPressure();
  // Calculate altitude assuming 'standard' barometric pressure of 1013.25 millibars (101325 Pascals).
  _altitude = bmp.readAltitude();
  _sea_level_pressure = bmp.readSealevelPressure();
  // To get a more precise altitude measurement, use the current sea level pressure, which will vary with the weather conditions. 
  _real_altitude = bmp.readAltitude(101500);
  // Print the data generated by the BMP180 Barometric Pressure/Temperature/Altitude Sensor.
  Serial.print("Temperature => "); Serial.print(_temperature); Serial.println(" *C");
  Serial.print("Pressure => "); Serial.print(_pressure); Serial.println(" Pa");
  Serial.print("Altitude => "); Serial.print(_altitude); Serial.println(" meters");
  Serial.print("Pressure at sea level (calculated) => "); Serial.print(_sea_level_pressure); Serial.println(" Pa");
  Serial.print("Real Altitude => "); Serial.print(_real_altitude); Serial.println(" meters\n");
}

void err_msg(){
  // Show the error message on the SSD1306 screen.
  adjustColor(255, 0, 0);
  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();  
}

void blePeripheralConnectHandler(BLEDevice central) {
  // Central connected event handler:
  Serial.print("Connected event, central: ");
  Serial.println(central.address());
}

void blePeripheralDisconnectHandler(BLEDevice central) {
  // Central disconnected event handler:
  Serial.print("Disconnected event, central: ");
  Serial.println(central.address());
}

void adjustColor(int r, int g, int b){
  analogWrite(redPin, (255-r));
  analogWrite(greenPin, (255-g));
  analogWrite(bluePin, (255-b));
}

void ei_printf(const char *format, ...){
  static char print_buf[1024] = { 0 };
  va_list args;
  va_start(args, format);
  int r = vsnprintf(print_buf, sizeof(print_buf), format, args);
  va_end(args);
  if(r > 0){ Serial.write(print_buf); }
}

Credits

Kutluhan Aktar

Kutluhan Aktar

82 projects • 309 followers
AI & Full-Stack Developer | @EdgeImpulse | @Particle | Maker | Independent Researcher

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