Goal of the challenge #moveandchill of makezurich.ch 2020

Proof of concept based on the Arduino Nano BLE 33 to measure how public chairs are used in the city of Zurich during the #makezurich hackathon.

It is an implementation of the #moveandchill challenge.

See the RESULTS for a summary of the achievements.

Resources

• lorawan library to communicate with the lorawan module Murata ST B-L072Z-LRWAN1 or the Miromico FMLR-72-U-STL0Z
• tech specs and description
• schematic pdf
• output examples
• data output on thingspeak

Setup

git submodule update --init --recursive

Resources and ideas

• wifi scanner was used for location detection on this bachelor thesis about location of working tools
• google api to get location from wifi ssids
• relative positioning by ble directional localisation with the help of a ble gateway
• esp32 with wifi module to scan wifi
• focus on usage of chair first/as separate task?
• flex bent sensor to detect if chair used
• IMU sensor to detect movement which shows chair in use

Things to do

• [X] 1st connection of arduino nano 33
• [X] build arduino library to commuincate with murata module
• [X] occupancy detection of a chair
  • [X] infrared
  • [X] flexbend (quadratic)
  • [X] strain gauge / load cell with HX711
• [X] function to check if chair in the sun or not
• [X] measure duration of occupancy
• [X] send data to ttn
• [X] pass data to some db which is publicly available
• [ ] detect position of chair

Manual fix about attachInterrupt only calling one

• see this patch
• fixed in this file: ~/.platformio/packages/framework-arduino-nrf52-mbedos/cores/arduino/Interrupts.cpp

Inital setup calls I did to set things up (platformio)

pio project init --board nano33ble
pio lib install 6590 # hts221 (temperature, humidity) 
pio lib install 6591 # lps22hb (barometric pressure)
pio lib install 6589 # lsm9ds3 (9-axis imu)
pio lib install 6616 # light APDS9960
pyenv virtualenv 3.7.8 chair
pyenv local chair
cd lib; git submodule  add git@github.com:2ni/lorawan_modem.git