Arduino Project

Arduino Heart Rate Monitor with MAX30102 V4

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2.png__PID:4c058c33-95c6-4f46-b6eb-562b4ffd4bdf

Name	Includes Arduino board	PURCHASE LINK
Elite Explorer Kit	Arduino Uno R4 WiFi	BUY
3 in 1 Ultimate Starter Kit	Arduino Uno R4 Minima	BUY

Course Introduction

This Arduino project builds a Heart Rate Monitor using the MAX30102 sensor, an OLED display, and an 8-LED NeoPixel module. It detects heartbeats and calculates the heart rate in BPM, which is displayed on the OLED.

The NeoPixel LEDs light up and turn off one by one with each detected heartbeat, creating a visual heartbeat effect.

Note

If this is your first time working with an Arduino project, we recommend downloading and reviewing the basic materials first.

1.1 Install Arduino IDE(Important)
1.2 Introduction of Arduino IDE

Required Components

In this project, we need the following components:

SN	COMPONENT INTRODUCTION	QUANTITY	PURCHASE LINK
1	Arduino UNO R4 WIFI	1	BUY
2	USB Type-C cable	1	×
3	Breadboard	1	BUY
4	Wires	Several	BUY
5	OLED Display Module	1	BUY
6	Pulse Oximeter and Heart Rate Sensor Module (MAX30102)	1	BUY
7	LED Strip	1	BUY

Wiring

heart_rate4.0_bb.png__PID:4a94feb8-6188-4857-8c78-d4e05b51f350

Common Connections:

Pulse Oximeter and Heart Rate Sensor Module (MAX30102)
SDA: Connect to A4 on the Arduino.
SCL: Connect to A5 on the Arduino.
GND: Connect to breadboard’s negative power bus.
VIN: Connect to breadboard’s red power bus.

OLED Display Module
SDA: Connect to A4 on the Arduino.
SCK: Connect to A5 on the Arduino.
GND: Connect to breadboard’s negative power bus.
VCC: Connect to breadboard’s red power bus.

LED Strip
Din: Connect to 6 on the Arduino.
GND: Connect to breadboard’s negative power bus.
+5V: Connect to breadboard’s passive power bus.

Writing the Code

Note
You can copy this code into Arduino IDE.
To install the library, use the Arduino Library Manager and search for Adafruit SSD1306 , Adafruit GFX , MAX30105 and heartRate and install it.
Don’t forget to select the board(Arduino UNO R4 Minima/WIFI) and the correct port before clicking the Upload button.

#ifdef LED_RED
#undef LED_RED
#endif

#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <Adafruit_NeoPixel.h>
#include <Wire.h>
#include "MAX30105.h"
#include "heartRate.h"

// =====================================================
// OLED settings
// =====================================================
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET -1
#define SCREEN_ADDRESS 0x3C

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

// =====================================================
// NeoPixel settings
// Arduino UNO R4 WiFi: use D6
// =====================================================
#define LED_PIN 6
#define NUM_LEDS 8

Adafruit_NeoPixel strip(
  NUM_LEDS,
  LED_PIN,
  NEO_GRB + NEO_KHZ800
);

// =====================================================
// MAX30102 heart rate sensor
// =====================================================
MAX30105 particleSensor;

const byte RATE_SIZE = 4;
byte rates[RATE_SIZE] = {0, 0, 0, 0};
byte rateSpot = 0;
byte validRateCount = 0;

long lastBeat = 0;
float beatsPerMinute = 0;
int beatAvg = 0;

// =====================================================
// LED heartbeat animation
// =====================================================
enum PulseState {
  PULSE_IDLE,
  PULSE_RISING,
  PULSE_FALLING
};

PulseState pulseState = PULSE_IDLE;

unsigned long pulseTimer = 0;

// Speed of individual LEDs
const unsigned long LED_STEP_TIME = 22;

int ledStep = 0;

// =====================================================
// Small heart icon
// =====================================================
static const unsigned char PROGMEM beat1_bmp[] = {
  0x03, 0xC0, 0xF0, 0x06, 0x71, 0x8C,
  0x0C, 0x1B, 0x06, 0x18, 0x0E, 0x02,
  0x10, 0x0C, 0x03, 0x10, 0x04, 0x01,
  0x10, 0x04, 0x01, 0x10, 0x40, 0x01,
  0x10, 0x40, 0x01, 0x10, 0xC0, 0x03,
  0x08, 0x88, 0x02, 0x08, 0xB8, 0x04,
  0xFF, 0x37, 0x08, 0x01, 0x30, 0x18,
  0x01, 0x90, 0x30, 0x00, 0xC0, 0x60,
  0x00, 0x60, 0xC0, 0x00, 0x31, 0x80,
  0x00, 0x1B, 0x00, 0x00, 0x0E, 0x00,
  0x00, 0x04, 0x00
};

// =====================================================
// Large heart icon
// =====================================================
static const unsigned char PROGMEM beat2_bmp[] = {
  0x01, 0xF0, 0x0F, 0x80, 0x06, 0x1C, 0x38, 0x60,
  0x18, 0x06, 0x60, 0x18, 0x10, 0x01, 0x80, 0x08,
  0x20, 0x01, 0x80, 0x04, 0x40, 0x00, 0x00, 0x02,
  0x40, 0x00, 0x00, 0x02, 0xC0, 0x00, 0x08, 0x03,
  0x80, 0x00, 0x08, 0x01, 0x80, 0x00, 0x18, 0x01,
  0x80, 0x00, 0x1C, 0x01, 0x80, 0x00, 0x14, 0x00,
  0x80, 0x00, 0x14, 0x00, 0x80, 0x00, 0x14, 0x00,
  0x40, 0x10, 0x12, 0x00, 0x40, 0x10, 0x12, 0x00,
  0x7E, 0x1F, 0x23, 0xFE, 0x03, 0x31, 0xA0, 0x04,
  0x01, 0xA0, 0xA0, 0x0C, 0x00, 0xA0, 0xA0, 0x08,
  0x00, 0x60, 0xE0, 0x10, 0x00, 0x20, 0x60, 0x20,
  0x06, 0x00, 0x40, 0x60, 0x03, 0x00, 0x40, 0xC0,
  0x01, 0x80, 0x01, 0x80, 0x00, 0xC0, 0x03, 0x00,
  0x00, 0x60, 0x06, 0x00, 0x00, 0x30, 0x0C, 0x00,
  0x00, 0x08, 0x10, 0x00, 0x00, 0x06, 0x60, 0x00,
  0x00, 0x03, 0xC0, 0x00, 0x00, 0x01, 0x80, 0x00
};

// =====================================================
// Setup
// =====================================================
void setup() {
  Serial.begin(9600);

  // UNO R4 WiFi I2C:
  // SDA = A4
  // SCL = A5
  Wire.begin();
  Wire.setClock(400000);

  // ---------------------------------------------------
  // NeoPixel
  // ---------------------------------------------------
  strip.begin();
  strip.setBrightness(100);
  strip.clear();
  strip.show();

  // ---------------------------------------------------
  // OLED
  // ---------------------------------------------------
  if (!display.begin(
        SSD1306_SWITCHCAPVCC,
        SCREEN_ADDRESS
      )) {

    Serial.println("OLED not found");

    while (true);
  }

  display.clearDisplay();
  display.display();

  // ---------------------------------------------------
  // MAX30102
  // ---------------------------------------------------
  if (!particleSensor.begin(
        Wire,
        I2C_SPEED_FAST
      )) {

    Serial.println("MAX30102 not found");

    while (true);
  }

  particleSensor.setup();

  particleSensor.setPulseAmplitudeRed(0x0A);

  particleSensor.setPulseAmplitudeGreen(0);

  Serial.println("Place your finger on the sensor.");
}

// =====================================================
// Main loop
// =====================================================
void loop() {

  // Update NeoPixel animation continuously
  updateHeartLED();

  // Read IR value from MAX30102
  long irValue = particleSensor.getIR();

  // ===================================================
  // Finger detected
  // ===================================================
  if (irValue > 50000) {

    if (checkForBeat(irValue)) {

      unsigned long currentBeat = millis();

      // Ignore BPM calculation for the first heartbeat
      if (lastBeat > 0) {

        long delta = currentBeat - lastBeat;

        beatsPerMinute =
          60.0 / (delta / 1000.0);

        if (
          beatsPerMinute > 20 &&
          beatsPerMinute < 255
        ) {

          rates[rateSpot] =
            (byte)beatsPerMinute;

          rateSpot =
            (rateSpot + 1) % RATE_SIZE;

          if (validRateCount < RATE_SIZE) {
            validRateCount++;
          }

          int total = 0;

          for (
            byte i = 0;
            i < validRateCount;
            i++
          ) {
            total += rates[i];
          }

          beatAvg =
            total / validRateCount;
        }
      }

      lastBeat = currentBeat;

      // Start LED heartbeat animation
      startHeartLED();

      // ------------------------------------------------
      // OLED display
      // ------------------------------------------------
      display.clearDisplay();

      display.drawBitmap(
        18,
        10,
        beat2_bmp,
        32,
        32,
        SSD1306_WHITE
      );

      display.setTextColor(
        SSD1306_WHITE
      );

      display.setTextSize(2);

      display.setCursor(60, 10);
      display.println("BPM");

      display.setCursor(60, 28);
      display.println(beatAvg);

      display.display();

      // ------------------------------------------------
      // Serial monitor
      // ------------------------------------------------
      Serial.print("IR=");
      Serial.print(irValue);

      Serial.print(", BPM=");
      Serial.print(beatsPerMinute);

      Serial.print(", Avg BPM=");
      Serial.println(beatAvg);
    }
  }

  // ===================================================
  // Finger not detected
  // ===================================================
  else {

    pulseState = PULSE_IDLE;

    strip.clear();
    strip.show();

    lastBeat = 0;
    beatAvg = 0;
    validRateCount = 0;
    rateSpot = 0;

    display.clearDisplay();

    display.setTextSize(1);
    display.setTextColor(
      SSD1306_WHITE
    );

    display.setCursor(30, 5);
    display.println("Please place");

    display.setCursor(30, 15);
    display.println("your finger");

    display.setCursor(30, 25);
    display.println("and wait...");

    display.display();
  }
}

// =====================================================
// Start LED heartbeat animation
// =====================================================
void startHeartLED() {

  ledStep = 0;

  strip.clear();
  strip.show();

  pulseState =
    PULSE_RISING;

  pulseTimer = millis();
}

// =====================================================
// Update LED heartbeat animation
// =====================================================
void updateHeartLED() {

  unsigned long now = millis();

  // ---------------------------------------------------
  // Light LEDs one by one
  // ---------------------------------------------------
  if (
    pulseState ==
    PULSE_RISING
  ) {

    if (
      now - pulseTimer >=
      LED_STEP_TIME
    ) {

      pulseTimer = now;

      strip.setPixelColor(
        ledStep,
        strip.Color(
          255,
          0,
          0
        )
      );

      strip.show();

      ledStep++;

      // Peak of heartbeat
      if (
        ledStep >=
        NUM_LEDS
      ) {

        ledStep =
          NUM_LEDS - 1;

        pulseState =
          PULSE_FALLING;
      }
    }
  }

  // ---------------------------------------------------
  // Turn LEDs off one by one
  // ---------------------------------------------------
  else if (
    pulseState ==
    PULSE_FALLING
  ) {

    if (
      now - pulseTimer >=
      LED_STEP_TIME
    ) {

      pulseTimer = now;

      strip.setPixelColor(
        ledStep,
        0,
        0,
        0
      );

      strip.show();

      ledStep--;

      if (ledStep < 0) {

        strip.clear();
        strip.show();

        pulseState =
          PULSE_IDLE;
      }
    }
  }
}

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Arduino Project

Arduino Heart Rate Monitor with MAX30102 V4

Kit purchase

Course Introduction

Required Components

Wiring

Common Connections:

Writing the Code

Arduino Project

Arduino Heart Rate Monitor with MAX30102 V4

Kit purchase

Course Introduction

Required Components

Wiring

Common Connections:

Writing the Code

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