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2024 Science Fair Project

INVISION

INtegrated VItal SIgns mONitor

A low-cost, wearable multi-modal biosensor system for continuous health monitoring and early detection of vital sign anomalies.

Biomedical Engineering Wearable Tech ESP32 Health Monitoring

Overview

INVISION is a wearable armband that combines optical, acoustic, electrical, and temperature sensors to provide comprehensive vital signs monitoring for under $10.

Designed for at-risk individuals such as the elderly and those with chronic conditions, INVISION enables continuous health monitoring, early anomaly detection, and remote caregiver alerts.

Key Characteristics

Wearable
Non-invasive
Multi-sensor
Anomaly Detection
Remote Monitoring
Predictive AI
Alert System
Under $10 Cost

The Problem

This project was inspired by personal experience with elderly family members needing continuous health monitoring.

28% of adults 65+ live alone ~16.2 million individuals in the US
80% of seniors 65+ have chronic conditions Requiring continuous monitoring
14M+ falls annually among seniors 1 in 4 adults 65+ fall each year

Market Gap

Fitness Wearables

Track basic vitals (heart rate, steps) but limited functionality, not designed for early anomaly detection, fitness-focused only.

Clinical Equipment

Monitor critical vitals but high cost, mobility issues, continuous power needs, requires expert interpretation.

Technical Implementation

INVISION uses an ESP32 microcontroller connected to four sensor modules, powered by a 3.3V battery. Data flows to cloud storage for processing, a mobile app for the user interface, and an alert system for notifications.

How It Works

Uses the Beer-Lambert Law to analyze absorbance across different wavelengths of light as they pass through the skin. Different wavelengths are absorbed differently by oxygenated vs deoxygenated blood.

Key Measurements
  • Pulse rate from green light absorption patterns
  • Blood oxygen saturation (SpO2) from red/infrared ratio
  • Potential glucose estimation from NIR wavelengths
How It Works

A thermistor changes resistance based on temperature. Using a voltage divider circuit with a known resistor and input voltage, we measure the thermistor voltage and calculate temperature.

Key Measurements
  • Skin temperature (contact sensor)
  • Ambient temperature (reference sensor)
  • Temperature trends over time
How It Works

The ESP32 drives a small speaker to generate discrete sensing signals. A microphone captures vibrations transmitted through the skin, detecting the characteristic "lub-dub" heart sounds.

Key Measurements
  • Heart rate from sound interval timing
  • Heart sound patterns (S1, S2 detection)
  • Potential murmur or arrhythmia detection
How It Works

Multiple closely-spaced electrodes detect the electrical signals generated by the heart. The configuration allows 4-lead EKG-equivalent measurements from a single wearable location.

Key Measurements
  • Heart rate and rhythm
  • QRS complex detection
  • Arrhythmia indicators

System Architecture

ESP32 Microcontroller → Four Sensor Modules → Cloud Processing → Mobile App + Alert System → Healthcare Provider

Research Questions

Primary

Can a low-cost, multi-modal biosensor system detect physiological deviations from baseline using optical, acoustic, and electrical sensors?

Primary

How can a wearable multi-modal biosensor suite effectively detect early vital sign anomalies to improve health outcomes?

Secondary

What is the optimal method for integrating multiple sensing modalities in a compact, wearable design?

Secondary

How can real-time signal processing be achieved with minimal power consumption?

Applications

Remote Home Monitoring

For elderly, immunocompromised individuals, and people with disabilities

Chronic Disease Management

Continuous monitoring for diabetes, heart disease, and other conditions

Post-Surgery Recovery

Track vital signs during recovery at home

Rural Healthcare

Remote patient monitoring for underserved communities

Workplace Safety

Monitoring for high-risk occupations

Fall Detection

Emergency detection and automatic alerts

Future Work

1

Multi-channel Alerting

Develop multiple forms of alerting users and healthcare providers

2

Improved Form Factor

Make the device less obtrusive using flexible printed circuit boards (PCB)

3

Health App Integration

Connect with Apple Health, Google Health, and other platforms

4

Intelligent Data Collection

Optimize battery life with smart sampling algorithms

5

ML-Based Predictions

User clustering and predictive models for early intervention

Team

Adi Desai

Co-developer

Anika Shah

Co-developer

Mentorship

Dr. Abizar Lakdawalla

Project Mentor