Month: December 2018

Update to OpenSeizureDetector Android App

I need to update the OpenSeizureDetector Android App (https://github.com/OpenSeizureDetector/Android_Pebble_SD).   This is because the rules on apps having direct access to telephone and SMS services are changing, and if I don’t update how I do SMS messages, the app will be deleted from the Google Play Store.

Now since I don’t do many updates the the App, I am thinking of doing a few other changes at the same time, so the changes will be:

  1. Change method of sending SMS text messages to be consistent with the new rules.
  2. Add an extra ‘Passive Network Data Source’ which seems to be the way to communicate with alternative devices such as Garmin and Fitbit smart watches.
  3. Add the skeleton of a ‘BLE Data Source’ that I will use for the (possible) future Open Hardware seizure detection watch.
  4. See if I can work out why we sometimes end up with more than one copy of the background service running, which can cause some odd behaviours when you change settings.

Are there any other ‘features’ that are a annoying users that you would like me to have a look at as part of this update?   Please either post to the Facebook Page, or drop me an email with any thoughts (graham@openseizuredetector.org.uk).

Thanks!

Graham.

Update on Custom Hardware Seizure Detector

I have been working on the custom hardware seizure detector for a couple of weeks.    The code and schematics are on Github. 

Progress to date:

  • We can write firmware for the ESP32 microcontroller using the FreeRTOS framework 🙂
  • Access the I2C bus to talk to external sensors (such as the ADXL345 accelerometer).
  • Wire multiple devices to the I2C bus (I have a heart rate and blood oxygen saturation sensor, and a small display on it too).
  • Proved that we can communicate with both the accelerometer and display modules.

In Progress at the moment:

  • Modifying the I2C bus access code to make sure that only one process accesses the bus at a time, otherwise things will go horribly wrong when we try to use multiple devices, all managed by their own software process (task in FreeRTOS speak).
  • Ordered the main parts for the prototype (I am feeling lucky that I will get the ESP32 based system power consumption down far enough to complete the Proof-of-Concept.

The current proof-of-concept hardware is a rats nest of interconnected bought-in modules – not pretty!

Proof-of-Concept OSDWatch Hardware (ESP32 based)

Work to Do to Complete Proof-of-Concept

  • Complete the I2C bus access framework and routines to access:
    • ADXL345 Accelerimater
    • MAX300102 Heart Rate and Saturation module
    • OLED Display
  • Write code to send data to parent device over bluetooth periodically.
  • Check Power Consumption
    • Switch off the un-used ESP32 peripherals (e.g. WIFI) to reduce power consumption to give us at least 12 hours from a small LiPo battery.

Work to do for Prototype

  • Design a custom PCB to hold the main components (rather than using bought in modules that are wired together) – necessary to get it down to wrist watch size.
  • Get a small number of PCBs manufactured (there seem to be a few companies that do this cheaply in China).
  • Design a watch case, and manufacture a few using 3D printing.
  • Populate PCBs with components and solder them.
  • Test using proof-of-concept code.
  • Extend the OpenSeizureDetector android app to have a new Data Source which will be the custom OSD watch
  • Update the firmware to communicate with the Android App.