Cleaner data makes better estimates.
Optical sensing is sensitive to movement, signal quality and contact conditions. Filtering and reliable peak extraction matter as much as the sensing hardware.
PROJECT NO. 001 / EMBEDDED ELECTRONICSFINAL-YEAR UNIVERSITY PROJECT / 2025
ENGINEERING A SIGNAL THAT MATTERS
THE SIGNAL
OF LIFE.
A home-use heart-monitoring prototype exploring the relationship between optical sensing, embedded processing, energy management and connected interfaces.
FIG / 01HEART BEAT / OPTICAL SENSING
SIMPLIFIED ORIGINAL VISUALNOT A PCB LAYOUT
PLATFORMESP32
SENSORMAX30102
ENERGYSOLAR-POWERED
OUTPUTMOBILE INTERFACE
01 / OVERVIEW
MEASURE.
INTERPRET.
COMMUNICATE.
For my university project, I designed a home heart-monitoring prototype built around an ESP32 microcontroller and a MAX30102 optical pulse sensor. The system brings together sensing, signal conditioning, digital filtering, heart-rate estimation, solar-energy harvesting and wireless data delivery.
This case study explains the architecture and design scope described in my CV. The diagrams are newly drawn educational interpretations—not photographs of the assembled hardware or published test data.
02 / SYSTEM ARCHITECTURE
ONE SIGNAL.
FIVE STAGES.
Every stage has a job. Explore the chain from sensing to information and the separate energy path that supports the electronics.
01OPTICAL INPUT
MAX30102 acquires a photoplethysmography signal related to pulsatile blood-volume change.
SENSOR02SIGNAL CONDITIONING
Prepare the acquired readings for processing and reduce unwanted variation through filtering.
PREPROCESS03RATE ESTIMATION
Estimate heart rate from processed optical pulse information.
ESP3204WIRELESS DATA
Transmit the resulting information to a connected mobile interface.
COMMUNICATE05MOBILE DISPLAY
Make the information available to a user through a mobile interface.
INTERFACEENERGY SUPPLY / PARALLEL SYSTEMSOLAR HARVESTING → POWER MANAGEMENT → ELECTRONICS
03 / ENGINEERING REFLECTIONS
THE WORK
IS IN THE
DETAILS.
Autonomy demands discipline.
A solar-assisted device needs careful accounting of consumption, energy harvesting, storage, and variations in available light. These are important validation requirements, not claims of measured autonomy.
Engineering finishes with communication.
Measurement is only part of the system: information needs to be delivered clearly, reliably and without implying medical diagnostic certainty.
04 / NEXT-STAGE VALIDATION
WHAT I'D
TEST NEXT.
Before treating a prototype as a deployable device, I'd validate it against reference instrumentation, stress-test signal quality under movement, inspect wireless reliability, and measure actual consumption and charging behavior. No clinical accuracy, battery-life figures or safety certifications are claimed here.
Educational university engineering project. Not a certified medical device or diagnostic instrument.
THE NEXT CONNECTION.