Published May 1, 2020 © CC BY-SA

Relaxation Breathing Exercise Tracker

A device to guide and track breathing exercise sessions for post Covid recovery of patient's lung capacity

BeginnerFull instructions provided2 hours821

Things used in this project

Hardware components

Texas Instruments EK-TM4C123GXL TM4C Tiva LaunchPad

1.54 Inch E-paper display

Hall Effect Fluid Flow Sensor

Mouth tip

Buzzer

Battery Holder, AA x 3

AA Batteries

Software apps and online services

Texas Instruments Energia

Hand tools and fabrication machines

Tape, Green

Box, General Purpose

Soldering iron (generic)

Hot glue gun (generic)

Premium Female/Female Jumper Wires, 40 x 3" (75mm)

Story

Deep Breathing Exercise

Deep breathing is a powerful technique to deal with stress and anxiety. Deep breathing exercise can alleviate these symptoms by allowing more air into the lung, calms the nervous system and restores heartbeat to regular rhythm.

Relaxation Deep Breathing Exercise Guide/Tracker may help with post Covid-19 infection recovery for patients with damaged lung. By performing lung exercise, patients can gradually restore full lung capacity.

Breathing Exercise Tracker for post Covid recovery

Device Operation & Demonstration

The device consists of two parts :-

Air breathing mouthpiece
Controller box

The mouthpiece is basically a flow sensor for breathing air in & out. The controller box consists of a microcontroller development board and a display which will guide and inform user about the exercise session.

For visual indication there is an e-paper display which will provide :-

Breathing exercise guidance messages to the user
Breath tracking and counting information

In addition to the display there is the RGB LED that will change color :-

Blue blinking - Before breathing in
Blue solid - While breathing in
Red solid - Holding breath
Green blinking - Before breathing out
Green solid - While breathing out
White solid - Exercise session completed

There is also a buzzer that will beep after each breathe in-hold-out cycle.

Here is a demo showing how it works :-

Performing breathing exercise

Hardware Build

The solution is made with the following hardware :-

TIVA tm4c123 development board: This microcontroller board is used to build this prototype
1.54 inch epaper display: Show user breathing exercise instructions, breath counts, session completion information
Onboard RGB LED: This RGB LED quickly shows user the breathing in, breath holding, breathing out queue
Flow Sensor: Senses air flow during breathing in and out
Buzzer: Beeps after each breathing cycle
Red Plastic Box: Enclosure for the project
Green Tape: Masking the device

1 / 2 • Tiva tm4c123 development board and e paper display

I put the Tiva microcontroller development board inside a red plastic box, made a cut for the display and attached it with hot glue and green tape. I have also used a small piece of hot glue stick as a light pipe to transmit light from the RGB LED on Tiva development board. The flow sensor is connected to the development board with long female-female jumper wires. The device is powered from a 5V power bank but 3 AA battery will work too.

1 / 5 • Inside the controller box

All the connections are made according to this schematic :-

Schematic

Firmware Development

The code is written in C on Energia IDE which supports standard Arduino APIs/functions. In addition to that, it supports Tiva APIs for the microcontroller peripherals. Anyone familiar with Arduino ecosystem & C programming will understand the code. I have heavily commented the code for ease of understanding.

Energia IDE for writing firmware

Following resources can be useful to understand the APIs/functions in details :-

What's happening in the firmware ?

tm4c123 microcontroller drives the epaper display with SPI interface and shows some intro message and logo after power up.

Next, the display shows message to user to breathe in through the mouthpiece and the blue LED keeps blinking. When the user breathes air through the mouthpieces (flow sensor), it generates pulses which is sensed with falling edge interrupts on a GPIO pin of the microcontroller. The blue LED glows solid during the breath in time. When user stops breathing in, the interrupts also stop, blue LED turns RED, display shows user to hold breath for about 4 seconds. After that, RED LED goes off and the green LED starts blinking. The display will change the message again and tell user to breathe out, which is again sensed with pulses generated by the flow sensor, during this time green LED stays solid. Once the interrupt stops, breath counter is incremented, total number of breaths saved on eeprom.

This whole program loops until user has completed a given number of breaths, then the display shows used that the exercise is complete.

Conclusion

Breathing exercise tracker is a device to aid/guide someone who wishes to complete consistent deep breathing sessions regularly. It's a motivational tool to help people restoring lung capacity when they are not feeling energetic after recovering from Covid-19 infection. It will help patients to relax, restore energy and balance.

Of course, you don't need a breathing exercise tracker to do breathing exercise, just like you don't need a step counter to walk/run.

But, it helps achieving goals with breathing exercise sessions.

Code

///////////// Header Files ////////////////
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <inttypes.h>
#include <sysctl.h>
#include <eeprom.h>

#include <SPI.h>
#include "epd1in54.h"
#include "epdif.h"
#include "epdpaint.h"
#include "imagedata.h"

int COLORED  = 0; // White in Black on epaper
int UNCOLORED = 1;  // Black in White on epaper
unsigned char image[8120];  // buffer for epaper

// variable array to write and read eeprom
uint32_t romdata_written[2] ;
uint32_t romdata_read[2] ;

// ISR variable for frequency of flow sensor pulses
volatile unsigned long frequency = 0;
volatile unsigned long last_micro = 0;

// variable for number of breaths during exercise
uint32_t breath_counter = 0;
uint32_t net_breaths = 0;

/////////// Enum for epaper//////////////
////// width must be multiple of 8///////
Paint paint(image, 0, 0);  // epaper enum
Epd epd;                   // epaper enum

char VAL[9]; // buffer for int to char conversion

/////////////////////////////////////////////////
////////////// I/O pin mapping //////////////////

//// I/O pins used interfacing paper display ////
// see inside epdif.c , epdif.h files and also //
// check for tiva tm4c123 energia SPI0 pinmap  //

// #define RST_PIN   9  // PA6 (GPIO)
// #define DC_PIN    10 // PA7 (GPIO)
// #define BUSY_PIN  19 // PB2 (GPIO)
// #define MSI_SPI0  8  // PA5 (SPI0)
// #define MIS_SPI0  13 // PA4 (SPI0)
// #define CSL_SPI0  12 // PA3 (SPI0)
// #define CLK_SPI0  11 // PA2 (SPI0)
// note : MISO (PA4) has no actual physical wiring
//  between tm4c123 and epaper, just SPI MISO pin
///////////////////////////////////////////////////
///////////////////////////////////////////////////

//// Input for sensing AIR flow   ////
#define FLOW_METER 31       // PF4

//Tiva on board RGB LED for breath sequence//
#define LED_BLU 40           // PF2 
#define LED_RED 30           // PF1 
#define LED_GRN 39           // PF3 
#define BUZZER 32            // PD7 

///////////////////////////////////////////////
//ISR to measure pulses from air flow sensor //
///////////////////////////////////////////////
void PortFIntHandler()
{
  // clear interrupt
  uint32_t flag = 0;
  flag = GPIOIntStatus(GPIO_PORTE_BASE, true);
  GPIOIntClear(GPIO_PORTF_BASE, GPIO_INT_PIN_4);
  // measuring frequency // f=1000000/t (t in uSeconds)
  frequency = 1000000.0 / (micros() - last_micro);
  last_micro = micros();
  // time_passed =  last_micro- first_micro ;
}

////////////////////////////////////////////////
////////////////////////////////////////////////

void setup()
{
  // initialize I/O pins //
  pinMode(LED_RED, OUTPUT);
  pinMode(LED_BLU, OUTPUT);
  pinMode(LED_GRN, OUTPUT);
  pinMode(BUZZER,  OUTPUT);

  // wrire I/O pins init states //
  digitalWrite(LED_RED, LOW);
  digitalWrite(LED_BLU, LOW);
  digitalWrite(LED_GRN, LOW);
  digitalWrite(BUZZER,  LOW);

  // set PF4 as input pullup //
  pinMode(FLOW_METER, INPUT_PULLUP); // <---- PORT F pin 4, PF4

  // configure for falling edge interrupt
  GPIOIntTypeSet(GPIO_PORTF_BASE, GPIO_PIN_4, GPIO_FALLING_EDGE);

  // associate with ISR function
  GPIOIntRegister(GPIO_PORTF_BASE, PortFIntHandler);

  // enable interrupt to sense AIR flow pulses
  //GPIOIntEnable(GPIO_PORTF_BASE, GPIO_INT_PIN_4);

  // Initialize EEPROM for storing breathing data
  SysCtlPeripheralEnable(SYSCTL_PERIPH_EEPROM0);
  while (!SysCtlPeripheralReady(SYSCTL_PERIPH_EEPROM0))
  {}
  EEPROMInit();
  EEPROMRead(romdata_read, 0x80, sizeof(romdata_read));
  net_breaths = romdata_read[0];

  // clear and init e paper //
  flush_epd();
  init_epd();

 

  // flush_epd();
  // init_epd();
  // show device intro logo //
  // epd.SetFrameMemory(Meno_Logo);
  epd.DisplayFrame();
  delay(1200);

  flush_epd();
  init_epd();

  // enable interrupt to sense AIR flow pulses //
  GPIOIntEnable(GPIO_PORTF_BASE, GPIO_INT_PIN_4);
}

////////////////////////////////////////////////
////////////////////////////////////////////////

void loop()
{
  // all *_epd() and paint.*() -> epaper functions

  // show user instruction on display and LED //
  erase_epd();
  while (frequency == 0)
  {
    digitalWrite(LED_BLU, HIGH);
    delay(100);
    paint.DrawStringAt(8, 26, "TAKE A LONG" , &Font24, COLORED);
    paint.DrawStringAt(8, 60, "DEEP BREATH" , &Font24, COLORED);
    paint.DrawStringAt(5, 133, "Breath Counter:", &Font16, COLORED);
    paint.DrawStringAt(5, 155, "Past Sessions", &Font16, COLORED);
    paint.DrawStringAt(5, 170, "Breath Counts:", &Font16, COLORED);
    paint.DrawStringAt(170, 133, itoa(breath_counter, VAL, 10), &Font16, COLORED);
    paint.DrawStringAt(160, 170, itoa(net_breaths, VAL, 10), &Font16, COLORED);

    epd.SetFrameMemory(paint.GetImage(), 0, 0, paint.GetWidth(), paint.GetHeight());
    epd.DisplayFrame();
    digitalWrite(LED_BLU, LOW);
    delay(200);

  }
  // wait while breath in
  while (micros() < last_micro + 200000)
  {
    digitalWrite(LED_BLU, HIGH);
  }

  // hold breath

  digitalWrite(LED_BLU, LOW);
  digitalWrite(LED_RED, HIGH);
  erase_epd();
  paint.DrawStringAt(8, 26, " HOLD YOUR " , &Font24, COLORED);
  paint.DrawStringAt(8, 60, "  BREATH ! " , &Font24, COLORED);
  paint.DrawStringAt(5, 133, "Breath Counter:", &Font16, COLORED);
  paint.DrawStringAt(5, 155, "Past Sessions", &Font16, COLORED);
  paint.DrawStringAt(5, 170, "Breath Counts:", &Font16, COLORED);
  paint.DrawStringAt(170, 133, itoa(breath_counter, VAL, 10), &Font16, COLORED);
  paint.DrawStringAt(160, 170, itoa(net_breaths, VAL, 10), &Font16, COLORED);

  epd.SetFrameMemory(paint.GetImage(), 0, 0, paint.GetWidth(), paint.GetHeight());
  epd.DisplayFrame();


  delay(4000);
  digitalWrite(LED_RED, LOW);
  frequency = 0;

  erase_epd();
  while (frequency == 0)
  {

    digitalWrite(LED_GRN, HIGH);
    delay(100);
    paint.DrawStringAt(8, 26, "BREATH OUT" , &Font24, COLORED);
    paint.DrawStringAt(8, 60, "SLOWLY ..." , &Font24, COLORED);
    paint.DrawStringAt(5, 133, "Breath Counter:", &Font16, COLORED);
    paint.DrawStringAt(5, 155, "Past Sessions", &Font16, COLORED);
    paint.DrawStringAt(5, 170, "Breath Counts:", &Font16, COLORED);
    paint.DrawStringAt(170, 133, itoa(breath_counter, VAL, 10), &Font16, COLORED);
    paint.DrawStringAt(160, 170, itoa(net_breaths, VAL, 10), &Font16, COLORED);

    epd.SetFrameMemory(paint.GetImage(), 0, 0, paint.GetWidth(), paint.GetHeight());
    epd.DisplayFrame();
    digitalWrite(LED_GRN, LOW);
    delay(200);
  }

  // wait while breath out
  while (micros() < last_micro + 200000)
  {
    digitalWrite(LED_GRN, HIGH);
  }
  digitalWrite(LED_GRN, LOW);
  frequency = 0;
  breath_counter += 1;
  digitalWrite(BUZZER, HIGH);
  delay(150);
  digitalWrite(BUZZER, LOW);




  //******************************************//
  // update eeprom with breath count info //
  // *****************************************//

  EEPROMRead(romdata_read, 0x80, sizeof(romdata_read));

  // update data before writing to eeprom, (first 32 byte area)
  romdata_written[0] =  romdata_read[0] + 1;

  // write/save data to eeprom to 0x80 address with max size 64 bytes (32+32)
  EEPROMProgram(romdata_written, 0x80, sizeof(romdata_written));

  // Read eeprom 0x80 location data for new value
  EEPROMRead(romdata_read, 0x80, sizeof(romdata_read));
  net_breaths = romdata_read[0];

  if (breath_counter >= 5)
  {
    erase_epd();
    digitalWrite(LED_RED, HIGH);
    digitalWrite(LED_GRN, HIGH);
    digitalWrite(LED_BLU, HIGH);
    while (1)
    {

      paint.DrawStringAt(8, 15, "YOU JUST HAVE" , &Font20, COLORED);
      paint.DrawStringAt(8, 35, " SUCCESSFULLY" , &Font20, COLORED);
      paint.DrawStringAt(2, 55, "  COMPLETED  ", &Font20, COLORED);
      paint.DrawStringAt(2, 78, "  YOUR BREATHING ", &Font16, COLORED);
      paint.DrawStringAt(2, 93, " EXERCISE SESSION ", &Font16, COLORED);

      paint.DrawStringAt(5, 133, "Breath Counter:", &Font16, COLORED);
      paint.DrawStringAt(5, 155, "Past Sessions", &Font16, COLORED);
      paint.DrawStringAt(5, 170, "Breath Counts:", &Font16, COLORED);
      paint.DrawStringAt(170, 133, itoa(breath_counter, VAL, 10), &Font16, COLORED);
      paint.DrawStringAt(160, 170, itoa(net_breaths, VAL, 10), &Font16, COLORED);

      epd.SetFrameMemory(paint.GetImage(), 0, 0, paint.GetWidth(), paint.GetHeight());
      epd.DisplayFrame();

    }
  }

}

///////////////////////////////////////////////
////////////////main loop ends here ///////////
///////////////////////////////////////////////


///////////////////////////////////////////////
///////////// Function body ///////////////////
///////////////////////////////////////////////

// clean up dark spots on epaper display //

void flush_epd (void)
{
  if (epd.Init(lut_full_update) != 0)
  {
    return;
  }
  epd.ClearFrameMemory(0xFF);
  epd.DisplayFrame();
  //epd.ClearFrameMemory(0xFF);
  //epd.DisplayFrame();

}

// initialize full e paper display //

void init_epd(void)
{
  ///// Init Full Display Update ///////////
  if (epd.Init(lut_full_update) != 0)
  {
    return;
  }
  ///// Init Partial Display Update ////////
  if (epd.Init(lut_partial_update) != 0)
  {
    return;
  }
  ////////// Clears Up Full Disp ///////////
  // bit set = white, bit reset = black
  epd.ClearFrameMemory(0xFF);
  epd.DisplayFrame();
  // epd.ClearFrameMemory(0xFF);
  // epd.DisplayFrame();

}

// clean up lines on epaper //
void erase_epd(void)
{
  paint.SetWidth(200);
  paint.SetHeight(200);
  paint.SetRotate(ROTATE_180);
  paint.Clear(UNCOLORED);
}

Credits

Shahariar

71 projects • 262 followers

"What Kills a 'Great life' is a 'Good Life', which is Living a Life Inside While Loop"

Relaxation Breathing Exercise Tracker

Things used in this project

Hardware components

Software apps and online services

Hand tools and fabrication machines

Story

Deep Breathing Exercise

Device Operation & Demonstration

Hardware Build

Firmware Development

Conclusion

Schematics

Schematic

Code

main.c

full code

Credits

Shahariar

Comments

Embed the widget on your own site

Relaxation Breathing Exercise Tracker

Relaxation Breathing Exercise Tracker

Things used in this project

Hardware components

Software apps and online services

Hand tools and fabrication machines

Story

Deep Breathing Exercise

Device Operation & Demonstration

Hardware Build

Firmware Development

Conclusion

Schematics

Schematic

Code

main.c

full code

Credits

Shahariar

Comments

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