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Sebastian CausJohn CharlesVatsalya GoelBrett Anquetil
Published © GPL3+

eMotion - Towards a Better Future

We believe we can use biometric sensors, the security of the Helium platform and strength of Google Cloud to surface possible anxiety states

IntermediateFull instructions provided3 days12,407
eMotion - Towards a Better Future

Things used in this project

Hardware components

Helium Element Access Point (Cellular)
Helium Element Access Point (Cellular)
×1
Helium Atom Xbee Module
Helium Atom Xbee Module
×1
Helium Arduino/mbed Adapter
×1
Arduino UNO
Arduino UNO
×1
NeuroSky Mindwave Mobile 2
×1
Seeed Studio Grove GSR Sensor
×1
Pulse Sensor
×1
SparkFun Bluetooth Modem - BlueSMiRF Gold
×1
Terminal Shield for Arduino
×1

Software apps and online services

Firebase
Google Firebase
Cloud IoT Core
Google Cloud IoT Core

Story

Read more

Schematics

Circuit schematic

This is the representative schematic file (Helium Atom omitted for clarity)

Circuit diagram

This is our circuit as built, omitting the Helium Atom for clarity

Code

Source Code

Arduino
The program reads heart rate, galvanic skin response, and mindfulness from the connected sensors every 5 seconds and sends them to Google cloud via the Helium cloud.
After initializing the sensors and connecting to the Helium cloud, the program connects to each of the three sensors, collects the current data and formats it as a json string. This is then sent to Google cloud via Helium. It repeats every 5 seconds.
/****************************************************************************************************************
* Descdiption: Program to measure heart rate, GSR, and brain activity and send to Google cloud for analysis
*              to determine onset of Anxiety.
*              Uses ???? for heart rate monitoring
*              Uses ???? for GSR
*              Uses Neurosky mobile headset for measuring brain activity
*****************************************************************************************************************/
#define DEBUG 1                        // Will output messages to the serial monitor
#define USE_ARDUINO_INTERRUPTS true    // Set-up low-level interrupts for most acurate BPM math.
#define BAUDRATE 57600                 // The default for the bluesmirf

#include "Arduino.h"
#include "Board.h"
#include "Helium.h"
#include "HeliumUtil.h"
#include <PulseSensorPlayground.h>     // Includes the PulseSensorPlayground Library.  

#define CHANNEL_NAME "NeuroG"          // The name of the Helium channel configured to send data to Google cloud

//  Variables
const int PulseWire = 0;               // PulseSensor PURPLE WIRE connected to ANALOG PIN 0
const int GSRPin=A1;                   // GSR connected to Analog Pin 1
const int LED13 = 13;                  // The on-board Arduino LED, close to PIN 13.
int Threshold = 550;                   // Determine which Signal to "count as a beat" and which to ignore.
                             
PulseSensorPlayground pulseSensor;     // Creates an instance of the PulseSensorPlayground object called "pulseSensor"

Helium  helium(&atom_serial);          // Standard Helium objects
Channel channel(&helium);


void channel_send(void const * data, size_t len)  // used to send data to Helium channel
{
    int    status;
    int8_t result;

    status = channel.send(data, len, &result);
}

byte ReadOneByte()                     // Returns a byte from the Neurosky headset which is connected via bluesmirf bluetooth adaptor
{
  int ByteRead;

  while(!Serial.available());          // wait until there's some data then 
  ByteRead = Serial.read();            // get a single byte of data 

  #if DEBUG  
    Serial.print((char)ByteRead);      // echo the same byte out the USB serial (for debug purposes)
  #endif

  return ByteRead;
}


String getMindwaveData()               // read the data stream coming from the Mindwave and split into components
{                                      // adapted from http://developer.neurosky.com/docs/doku.php?id=mindwave_mobile_and_arduino
  // checksum variables
  byte generatedChecksum = 0;
  byte checksum = 0; 
  int payloadLength = 0;
  byte payloadData[64] = {0};
  
  // system variables
  long lastReceivedPacket = 0;
  boolean bigPacket = false;
  String MindwaveData;                 // a json formatted string of the values returned from the mindwave headset

  
  byte poorQuality = 0;                // indicates quality of signal from mindwave headset
  byte attention = 0;                  // level of attention reading as determined by mindwave headset
  byte meditation = 0;                 // level of meditation reading as determined by mindwave headset

  // Look for sync bytes
  while(ReadOneByte() != 170);

    if(ReadOneByte() == 170) {

      payloadLength = ReadOneByte();
      if(payloadLength > 169)                      //Payload length can not be greater than 169
          return;

      generatedChecksum = 0;        
      for(int i = 0; i < payloadLength; i++) {  
        payloadData[i] = ReadOneByte();            //Read payload into memory
        generatedChecksum += payloadData[i];
      }   

      checksum = ReadOneByte();                      //Read checksum byte from stream      
      generatedChecksum = 255 - generatedChecksum;   //Take one's compliment of generated checksum

        if(checksum == generatedChecksum) {    

        poorQuality = 200;
        attention = 0;
        meditation = 0;

        for(int i = 0; i < payloadLength; i++) {    // Parse the payload
          switch (payloadData[i]) {
          case 2:
            i++;            
            poorQuality = payloadData[i];
            bigPacket = true;            
            break;
          case 4:
            i++;
            attention = payloadData[i];                        
            break;
          case 5:
            i++;
            meditation = payloadData[i];
            break;
          case 0x80:
            i = i + 3;
            break;
          case 0x83:
            i = i + 25;      
            break;
          default:
            break;
          } // switch
        } // for loop

        // save the data into a json format string
        if(bigPacket) {
          MindwaveData += "\"poorQuality\":" + String(poorQuality) + ",";
          MindwaveData += "\"attention\":" + String(attention) + ",";
          MindwaveData += "\"meditation\":" + String(meditation);
        }
      }
    }

  return(MindwaveData);
}

String getHeartRate()                                     // read the heart rate from the pulse sensor
{                                                         // adapted from https://pulsesensor.com/pages/getting-advanced
  String HeartRate="";
 
  int myBPM = pulseSensor.getBeatsPerMinute();            // Calls function on our pulseSensor object that returns BPM as an "int".
                                                          // "myBPM" hold this BPM value now.
  if (pulseSensor.sawStartOfBeat()) {                     // Constantly test to see if "a beat happened".
    HeartRate = "\"heartRate\":" + String(myBPM) + ",";   // Save the heart rate as a json string
  }
  return(HeartRate);

}



String getGSR()                                           // read the galvanic skin response from the sensor on analogue pins
{
  int sensorValue=0;                                      // used for a single reading
  int gsr_average=0;                                      // to average 10 readings
  long sum=0;
  String GSR;                                             // json formatted string to return
  
  for(int i=0;i<10;i++)                                   // Average the 10 measurements to remove the glitch
     {
     sensorValue=analogRead(GSRPin);                      // GSR sensor connected to analogue pin
     sum += sensorValue;
     delay(5);
     }
  gsr_average = sum/10;                                   // calculate the average of the 10 readings
  GSR = "\"GSR\":" + String(gsr_average) + ",";

  return(GSR);
}

String readSensorMeasurements()                           // read from the 3 sensors and concatenate into a single string
{  
  String totalMessage;
 
  totalMessage = "{" ;
  totalMessage += getHeartRate();
  totalMessage += getGSR();
  totalMessage += getMindwaveData();
  totalMessage += "}";
  
  return(totalMessage);
}


void setup()
{
    Serial.begin(BAUDRATE);
    DBG_PRINTLN(F("Starting"));

    // Begin communication with the Helium Atom The baud rate differs
    // per supported board and is configured in Board.h
    helium.begin(HELIUM_BAUD_RATE);

    // Connect the Atom to the Helium Network
    DBG_PRINTLN(F("Connecting"));
    helium_connect(&helium);
    // and do a channel connect
    DBG_PRINTLN(F("Creating Channel"));
    channel_create(&channel, CHANNEL_NAME);
    DBG_PRINTLN(F("Channel created"));

   // Configure the PulseSensor object, by assigning our variables to it.
   pulseSensor.analogInput(PulseWire);  
   pulseSensor.blinkOnPulse(LED13);       //auto-magically blink Arduino's LED with heartbeat.
   pulseSensor.setThreshold(Threshold);  
  
   // Double-check the "pulseSensor" object was created and "began" seeing a signal.
    if (pulseSensor.begin()) {
     Serial.println("Checking......");  //This prints one time at Arduino power-up,  or on Arduino reset.  
    }
}

void loop()
{

    // Send some data to the configured channel
    int8_t result;
    String sensorMeasurements;
    size_t used;

    DBG_PRINTLN(F("Reading Sensors"));
    sensorMeasurements = readSensorMeasurements();
    used = sensorMeasurements.length();
    
    DBG_PRINT(F("Measurements - "));
    DBG_PRINTLN(sensorMeasurements);
    
    channel_send(sensorMeasurements.c_str(), used);
    DBG_PRINTLN(F("Sent to Helium"));

    // Wait a while till the next time
    delay(5000);
}

IoT Code

The program reads heart rate, galvanic skin response, and mindfulness from the connected sensors every 5 seconds and sends them to Google cloud via the Helium cloud. After initializing the sensors and connecting to the Helium cloud, the program connects to each of the three sensors, collects the current data and formats it as a json string. This is then sent to Google cloud via Helium. It repeats every 5 seconds.

Firebase Code

Code to demo the graphs on Firebase: https://neurog-206604.firebaseapp.com/ This program creates a function to subscribe to Google IoT Core and push the data to FireStore for further analysis. We then use the FireStore data to show live readings on a graph.

Credits

Sebastian Caus

Sebastian Caus

1 project • 5 followers
John Charles

John Charles

0 projects • 5 followers
Vatsalya Goel

Vatsalya Goel

0 projects • 4 followers
Brett Anquetil

Brett Anquetil

0 projects • 3 followers
IoT Solution Architect

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