This document is provisional only. It will be continueously updated with the development progress.
An MVP system hardware is a collection of 4 Sensor Nodes and 1 MVP App
flowchart LR
node1[[Node]] --(BLE)--> mvpapp((A laptop running MVP App))
node12 --(BLE)--> mvpapp
node13 --(BLE)--> mvpapp
node14 --(BLE)--> mvpapp
MVP system above is just for demonstrating the functions and capabilities. The actual system will not need a laptop, instead it will be usable from both laptops and mobile phnes.
flowchart LR
node1[[Node]] --(BLE)--> hub((Sensor Hub))
node12 --(BLE)--> hub
node13 --(BLE)--> hub
node14 --(BLE)--> hub
hub --(Bluetooth)--> phone(App running on a phone)
flowchart LR
sensor[[IMU sensor]] --(I2C)--> mcu{Nordic Bluetooth SoC}
button(Switch) --(GPIO)--> mcu
mcu --(GPIO)--> led(LED)
usb([USB Type C]) <--> mcu
usb --> charger(Charger)
charger --> battery(Battery)
battery --> mcu
| item | example | description |
|---|---|---|
| Nordic Bluetooth SoC | nRF52832 | A microcontroller with both Bluetooth and BLE capability. Note that some SoCs are only one of Bluetooth and BLE capable. We need both in the MVP development stage. Arduino compatibility is important in MVP development phase, to reduce development cost and time. To reduce the hardware design cost, using a pre-built Nordic module like Ublox BMD380 can also be an option. |
| IMU sensor | MPU6050 | There are many different IMU sensors with different number of axis, accuracy, and power profile. We need the most common one with good community software support to reduce the development cost. |
| USB Type C | Provides easier programmming / debugging in the development. It is also for recharging the battery. | |
| Charger | WS4518 | Any common 1-cell Li-ion/po battery charging chip with low quiescent current. |
| Battery | Sparkfun 40mAh battery | Any small Li-ion or Li-po battery with small form factor can be used. |
| Switch | One or two toggle button switches. With a single button, long-press can be power turn on/off, short click or double click can be used for paring / identifying itself from the App. | |
| LED | A single-color or 3-color LED for indication the node status |
timeline
title MVP System Development
week 1 : system design
: find developers
week 2 : sensor node schematics design
: sensor node PCB design
week 3,4 : PCBA prototyping
: buy battery
: buy JTAG tool
week 5 : hardware testing
week 6,7 : firmware development
: MVP app development
- Sensor Node : A small sensor device that
- can be attached to a special part of human body, e.g. hear ankle hinge.
- has IMU sensor(s).
- has a battery, rechargable or non-rechargable
- has wireless communication capability, e.g. BLE (Bluetooth Low Energy)
- Training : A session of physical training
- App : A mobile phone application or computer application with GUI (Graphical User Interface)
- MVP App : An application running on a laptop, with basic data collection functions like App does
journey
title Jose trains Hotte, analyse the performance together
section Training
Wear the sensor nodes: 3: Hotte
Turn on the sensor nodes and launch app: 5: Hotte, Jose
Perform a course: 1: Hotte
section Analysis
Check recorded data: 3: Jose
Teach and Learn: 1: Jose, Hotte
- First written on 4th Nov, 2024
- Last updated on 4th Nov, 2024