Comprehensive Personal Health Wearable

This project documents a wearable designed for personal health monitoring using Autodesk Fusion 360. This Nordic nRF54L15 powered wearable can monitor blood glucose levels, heart rate, blood oxygen levels, body temperature, and physical activity, such as step count.

The intent of this project is to build a wearable that can monitor all critical health parameters!

The image below shows a close-up of the wearable platform.

The wearable platform is designed around the BL54L15 module from Ezurio. It consists of the following components:

• BL54L15 module enabled by the nRF54L15 SoC
• NPM1300 PMIC for LiPo Battery Charging
• Adafruit EYESPI interface for connecting a display
• HLW5R-2C7LF Flex Connector for Blood Glucose Test Strip Interface
• ICS43434 I2S microphone
• MAX30102 Heart Rate / SpO2 sensor
• MLX90632 temperature sensor
• LSM6DS3TR-C IMU
• RTC chip with in-built clock
• M2 mounts for mounting display
• USB-C connector for serial debugging and external power
• CP2102 USB-Serial chip
• Qwiic I2C connector for sensor expansion
• SWD debug port

An annotated rendering of the components is shown in the image below:

Display

A 1.47" TFT display is connected to the wearable platform using flex cable as shown in the image below. A LiPo battery is connected to the back side (also shown in the image below).

Board bring-up

The board bring-up is complete and all peripherals are working. The documentation for this project is a work in progress. The debug LED in action is shown in the image below:

Display Test

The display was tested using an LVGL example and the display was working.

I2C interface test

The I2C sensors on the board are working. The snapshot below shows the sensors detected on the I2C bus.

The devices are as follows:

• 0x3B - MLX90632 I2C sensor
• 0x52 - RV-3028-C7 Real Time Clock
• 0x57 - MAX30102 Heart Rate Sensor
• 0x6A - NPM1300 PMIC
• 0x6B - LSM6DS3TR-C IMU

Things To Do

There are a few items pending in the project. They are:

• ADC calibration for Blood Glucose Monitor - Reference Glucose Solution is required to calibrate the blood glucose meter. This is a pending item. The image below shows a test strip interfaced to the wearable.

• The power consumption of the wearable in different phases needs to be profiled carefully.
• While the sensors and the display are working, they all need to be integrated together by writing drivers for them.

The documentation progress is going to continue in the repository shared below.