Pulse Sensor Plumbob

My final for my class Digital Multimedia we found an instructable we liked and we had to create something similar with our original twist.
On this site I found a gentleman who created his own version of the Sims Plumbob. (below is the link to his instructable)

https://www.instructables.com/id/LED-Light-Up-Sims-PlumbBob-That-green-pylon-above/

I use to play this game as a little girl & was in LOVE with it. Halloween had just passed but I still wanted to attempt to make something with this shape more 'meaningful' & 'important'.
I wanted it somehow to be able to blink and respond to my heartbeat. I had NO idea that there was a sensor out there (affordable) for a creative idea like this. I ordered my pulse sensor from adafruit.com and it only cost 20$ (plus tax and shipping). It took a few days for it to come into the mail considering I ordered on a Thursday but in the mean time I picked up some RGB LEDs from my local Radio Shack and went to my bread board to see what kind of Arduino coding I could mess with to make the RGB change colors.

I first became familiar with how the Arduino and the bread board work together with beginner examples of a blink for an LED.

Step 1: RGB LEDs

I must mention here, that I had many ups and downs trying to implement my idea. I wanted to use RGB LEDs in order to make certain colors relate to a specific heart beat with the heart pulse sensor.
The coding for the Arduino and the heart pulser code you can find on their site at : http://pulsesensor.com
After countless tries, there was just no way to make an RGB LED work with the pulse sensor coding. (If someone can figure it out!!! PROPS TO YOU!)
This was my first time ever working with an Arduino, and I believe my eyes were bigger than my stomach, and I took on a more difficult goal.. 

Step 2: Building

The next part is just how I built the plum bob structure. Again, you can see the guys step by step on his site.
I got slightly thicker wood dowels which made it not possible to have suspended over my head.
I also had a few wood dowels that ended up being cut a tad to short so I had to use a paper clip to help connect them together.

Step 3: Trial & Error

As I have mentioned, I wanted to use RGB LEDs.. It took me a long while to final realize and accept the fact that within my time frame I was not going to be able to figure out a code that would work with the pulse sensor to work with RGBs..
I then just used regular LEDs.. I started with one, but I wanted them to be bright enough to shine through a plastic bag. I first tried them on a circuit board, but the LEDs weren't all connect to one of the pins that essentially told the LED to pulse.. I had to go the crafty way to make them all work together.

Step 4: Arduino Coding

INTERRUPT

volatile int rate[10];                    // used to hold last ten IBI values
volatile unsigned long sampleCounter = 0;          // used to determine pulse timing
volatile unsigned long lastBeatTime = 0;           // used to find the inter beat interval
volatile int P =512;                      // used to find peak in pulse wave
volatile int T = 512;                     // used to find trough in pulse wave
volatile int thresh = 512;                // used to find instant moment of heart beat
volatile int amp = 100;                   // used to hold amplitude of pulse waveform
volatile boolean firstBeat = true;        // used to seed rate array so we startup with reasonable BPM
volatile boolean secondBeat = true;       // used to seed rate array so we startup with reasonable BPM


void interruptSetup(){    
  // Initializes Timer2 to throw an interrupt every 2mS.
  TCCR2A = 0x02;     // DISABLE PWM ON DIGITAL PINS 3 AND 11, AND GO INTO CTC MODE
  TCCR2B = 0x06;     // DON'T FORCE COMPARE, 256 PRESCALER
  OCR2A = 0X7C;      // SET THE TOP OF THE COUNT TO 124 FOR 500Hz SAMPLE RATE
  TIMSK2 = 0x02;     // ENABLE INTERRUPT ON MATCH BETWEEN TIMER2 AND OCR2A
  sei();             // MAKE SURE GLOBAL INTERRUPTS ARE ENABLED     
}


// THIS IS THE TIMER 2 INTERRUPT SERVICE ROUTINE.
// Timer 2 makes sure that we take a reading every 2 miliseconds
ISR(TIMER2_COMPA_vect){                         // triggered when Timer2 counts to 124
    cli();                                      // disable interrupts while we do this
    Signal = analogRead(pulsePin);              // read the Pulse Sensor
    sampleCounter += 2;                         // keep track of the time in mS with this variable
    int N = sampleCounter - lastBeatTime;       // monitor the time since the last beat to avoid noise

//  find the peak and trough of the pulse wave
    if(Signal < thresh && N > (IBI/5)*3){       // avoid dichrotic noise by waiting 3/5 of last IBI
        if (Signal < T){                        // T is the trough
            T = Signal;                         // keep track of lowest point in pulse wave
         }
       }

    if(Signal > thresh && Signal > P){          // thresh condition helps avoid noise
        P = Signal;                             // P is the peak
       }                                        // keep track of highest point in pulse wave

  //  NOW IT'S TIME TO LOOK FOR THE HEART BEAT
  // signal surges up in value every time there is a pulse
if (N > 250){                                   // avoid high frequency noise
  if ( (Signal > thresh) && (Pulse == false) && (N > (IBI/5)*3) ){       
    Pulse = true;                               // set the Pulse flag when we think there is a pulse
    digitalWrite(blinkPin,HIGH);                // turn on pin 13 LED
    IBI = sampleCounter - lastBeatTime;         // measure time between beats in mS
    lastBeatTime = sampleCounter;               // keep track of time for next pulse

         if(firstBeat){                         // if it's the first time we found a beat, if firstBeat == TRUE
             firstBeat = false;                 // clear firstBeat flag
             return;                            // IBI value is unreliable so discard it
            }  
         if(secondBeat){                        // if this is the second beat, if secondBeat == TRUE
            secondBeat = false;                 // clear secondBeat flag
               for(int i=0; i<=9; i++){         // seed the running total to get a realisitic BPM at startup
                    rate[i] = IBI;                     
                    }
            }

    // keep a running total of the last 10 IBI values
    word runningTotal = 0;                   // clear the runningTotal variable   

    for(int i=0; i<=8; i++){                // shift data in the rate array
          rate[i] = rate[i+1];              // and drop the oldest IBI value
          runningTotal += rate[i];          // add up the 9 oldest IBI values
        }

    rate[9] = IBI;                          // add the latest IBI to the rate array
    runningTotal += rate[9];                // add the latest IBI to runningTotal
    runningTotal /= 10;                     // average the last 10 IBI values
    BPM = 60000/runningTotal;               // how many beats can fit into a minute? that's BPM!
    QS = true;                              // set Quantified Self flag
    // QS FLAG IS NOT CLEARED INSIDE THIS ISR
    }                      
}

  if (Signal < thresh && Pulse == true){     // when the values are going down, the beat is over
      digitalWrite(blinkPin,LOW);            // turn off pin 13 LED
      Pulse = false;                         // reset the Pulse flag so we can do it again
      amp = P - T;                           // get amplitude of the pulse wave
      thresh = amp/2 + T;                    // set thresh at 50% of the amplitude
      P = thresh;                            // reset these for next time
      T = thresh;
     }

  if (N > 2500){                             // if 2.5 seconds go by without a beat
      thresh = 512;                          // set thresh default
      P = 512;                               // set P default
      T = 512;                               // set T default
      lastBeatTime = sampleCounter;          // bring the lastBeatTime up to date       
      firstBeat = true;                      // set these to avoid noise
      secondBeat = true;                     // when we get the heartbeat back
     }

  sei();                                     // enable interrupts when youre done!
}// end isr


ARDUINO

/*
>> Pulse Sensor Amped 1.1 <<
This code is for Pulse Sensor Amped by Joel Murphy and Yury Gitman
    www.pulsesensor.com
    >>> Pulse Sensor purple wire goes to Analog Pin 0 <<<
Pulse Sensor sample aquisition and processing happens in the background via Timer 2 interrupt. 2mS sample rate.
PWM on pins 3 and 11 will not work when using this code, because we are using Timer 2!
The following variables are automatically updated:
Signal :    int that holds the analog signal data straight from the sensor. updated every 2mS.
IBI  :      int that holds the time interval between beats. 2mS resolution.
BPM  :      int that holds the heart rate value, derived every beat, from averaging previous 10 IBI values.
QS  :       boolean that is made true whenever Pulse is found and BPM is updated. User must reset.
Pulse :     boolean that is true when a heartbeat is sensed then false in time with pin13 LED going out.

This code is designed with output serial data to Processing sketch "PulseSensorAmped_Processing-xx"
The Processing sketch is a simple data visualizer.
All the work to find the heartbeat and determine the heartrate happens in the code below.
Pin 13 LED will blink with heartbeat.
If you want to use pin 13 for something else, adjust the interrupt handler
It will also fade an LED on pin fadePin with every beat. Put an LED and series resistor from fadePin to GND.
Check here for detailed code walkthrough:
http://pulsesensor.myshopify.com/pages/pulse-sensor-amped-arduino-v1dot1

Code Version 02 by Joel Murphy & Yury Gitman  Fall 2012
This update changes the HRV variable name to IBI, which stands for Inter-Beat Interval, for clarity.
Switched the interrupt to Timer2.  500Hz sample rate, 2mS resolution IBI value.
Fade LED pin moved to pin 5 (use of Timer2 disables PWM on pins 3 & 11).
Tidied up inefficiencies since the last version.
*/


//  VARIABLES
int pulsePin = 0;                 // Pulse Sensor purple wire connected to analog pin 0
int blinkPin = 7;               // pin to blink led at each beat

int fadePin = 5;                  // pin to do fancy classy fading blink at each beat
int fadeRate = 0;                 // used to fade LED on with PWM on fadePin


// these variables are volatile because they are used during the interrupt service routine!
volatile int BPM;                   // used to hold the pulse rate
volatile int Signal;                // holds the incoming raw data
volatile int IBI = 600;             // holds the time between beats, the Inter-Beat Interval
volatile boolean Pulse = false;     // true when pulse wave is high, false when it's low
volatile boolean QS = false;        // becomes true when Arduoino finds a beat.


void setup(){

  pinMode(blinkPin,OUTPUT);         // pin that will blink to your heartbeat!
  pinMode(fadePin,OUTPUT);          // pin that will fade to your heartbeat!
  Serial.begin(115200);             // we agree to talk fast!
  interruptSetup();                 // sets up to read Pulse Sensor signal every 2mS
   // UN-COMMENT THE NEXT LINE IF YOU ARE POWERING The Pulse Sensor AT LOW VOLTAGE,
   // AND APPLY THAT VOLTAGE TO THE A-REF PIN
   //analogReference(EXTERNAL);  
}



void loop(){
  sendDataToProcessing('S', Signal);     // send Processing the raw Pulse Sensor data
  if (QS == true){                       // Quantified Self flag is true when arduino finds a heartbeat
        fadeRate = 255;                  // Set 'fadeRate' Variable to 255 to fade LED with pulse
        sendDataToProcessing('B',BPM);   // send heart rate with a 'B' prefix
        sendDataToProcessing('Q',IBI);   // send time between beats with a 'Q' prefix
        QS = false;                      // reset the Quantified Self flag for next time   
     }

  ledFadeToBeat();

  delay(20);                             //  take a break
}


void ledFadeToBeat(){
    fadeRate -= 10;                         //  set LED fade value
    fadeRate = constrain(fadeRate,0,255);   //  keep LED fade value from going into negative numbers!
    analogWrite(fadePin,fadeRate);          //  fade LED
  }


void sendDataToProcessing(char symbol, int data ){
    Serial.print(symbol);                // symbol prefix tells Processing what type of data is coming
    Serial.println(data);                // the data to send culminating in a carriage return
  }

Step 5: Final Production

&& VOLIA