DIY Wearable Pulse Oximeter & SpO2 Heart Rate Monitor with MAX30102

Educational Notes

This project is designed to be accessible to students from Class 4 to Masters level, with complexity scalable to match different age groups and skill levels.

Learning Objectives:

• Understand basic electronics and circuitry principles
• Learn sensor applications and data collection techniques
• Develop problem-solving skills through hands-on building and troubleshooting
• Apply programming concepts to control hardware and process data
• Connect projects to real-world Nepalese contexts and challenges

Adaptability:

• For younger students (Class 4-8): Focus on assembling pre-built circuits, observing results, and understanding basic concepts
• For intermediate students (Class 9-12): Modify code, experiment with parameters, and explore underlying principles
• For advanced students (Undergraduate/Masters): Optimize designs, add features, conduct research extensions, and analyze performance

Safety Note: Always supervise younger students when working with electricity, heat, or moving parts.

The MAX30102 Sensor Module shines red and infrared LEDs through finger capillary blood vessels to calculate pulse rate and blood oxygen (SpO2).

Hardware Bill of Materials:

• Microcontroller: Arduino Nano V3.0 Solderless
• Biometric Sensor: MAX30102 Heart Rate Pulse Oximeter Sensor Module
• Display: 0.91 inch OLED module blue OLED 128X32 GND-VCC-SCL-SDA
• Alert & Power: Active Buzzer + Type C TP4056 Charger Module + 18650 3.7V 3000mAh Battery

Circuit Pinout & Wiring Connections:

Firmware Source Code (ESP32 C++)

#include <WiFi.h>
#include <HTTPClient.h>

// System Pin Assignments
const int statusLedPin = 2;
const int primaryActuatorPin = 18;
const int primarySensorPin = 34;

void setup() {
  Serial.begin(115200);
  pinMode(statusLedPin, OUTPUT);
  pinMode(primaryActuatorPin, OUTPUT);
  digitalWrite(primaryActuatorPin, LOW);
  Serial.println("DIY Wearable Pulse Oximeter & SpO2 Heart Rate Monitor with MAX30102 Controller Operational.");
}

void loop() {
  int sensorValue = analogRead(primarySensorPin);
  Serial.printf("Telemetry Sensor Raw Input: %d\n", sensorValue);

  // Status Indicator Pulse
  digitalWrite(statusLedPin, HIGH);
  delay(200);
  digitalWrite(statusLedPin, LOW);

  delay(1800);
}