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README.md

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+# mobile senseBox
+
+This is some Arduino code for GPS tracked senseBoxes.
+They have an SDS011 particulate matter sensor & HDC1008 Temp & Humidity sensor
+attached and transmit their measurements to opensensemap.org.
+
+There are multiple variants to make use of various hardware I had available, and
+to evaluate different use cases and workflows of data transmission.
+
+Each sketch folder has its own readme with (more or less) detailed documentation.
+The `libraries` folder contains all code that any sketch may depend on.
+The the most simple solution to use these sketches is to make a backup of your
+existing `~/Arduino` folder, and clone this repository there instead:
+
+```sh
+mv ~/Arduino ~/Arduino.bak
+git clone https://github.com/noerw/mobile-sensebox ~/Arduino
+```
+
+## Hardware
+The microcontroller & communication protocol differs for the sketches, but all
+variants require a GPS device, a microcontroller with I2C, 2 UARTs (or some sort
+of software UART), as well as an Novafit SDS011 & a Bosch HDC1008.
+
+My builds of all these setups are powered by a 5.6Ah LiPo through an Adafruit
+LiPo charger via USB, and enclosed in a 15x8x8 case.
+The humidity sensor is included for reference, as the SDS011 only provides valid
+data at low humidity. The sensor is enclosed within the case (which heats up
+quite a bit), which makes the measurements quite inaccurate, they should only be
+treated as approximations.
+This setup is quite suboptimal for regular deployment (eg. daily commute by
+bike), see `Future Work`.
+
+### `./lora-gps`
+Arduino Mega + Dragino LoRa & GPS Shield + senseBox Shield (SD card)
+- transmitting data via LoRa to opensensemap.org through thethingsnetwork.org (details in SETUP.md)
+- additionally saving to SD card if no LoRa coverage is available
+- Arduino Uno should work as well, you need to play around with SoftSerial i guess..
+
+### `./esp8266-gps`
+Wemos D1 (ESP8266) + senseBox Shield
+- stores measurements locally on 3MB SPIFFS, and uploads via WiFi when available
+- requires installation of ESP8266 Arduino SDK, see `esp8266-gps/README.md`
+- senseBox shield only used for ease of use with JST-connectors, not needed
+
+### `./sdcard-gps`
+Arduino Mega + senseBox Shield
+- logging to SD card, manual upload to opensensemap.org
+
+## Future Work
+- Evaluation of SDS011 in a mobile environment: Influence of wind, sunlight,
+  vibrations, differing orientations
+
+- Averaging of measurement values
+    - tradeoff: less outliers <-> smaller spatial acurracy
+
+- Improved case
+    - power switch on the outside
+    - simple, quick mounting on a bike
+    - status LEDs about connectivity, GPS
+    - more neutral placement of humidity sensor
+    - all-weather proof
+
+# License
+- sketch directories:      MIT Norwin Roosen
+- `libraries` directory: see each subdirectory
+
+