Discussion and notes about the future logger

Design of the future board

Components to include, and Architecture

Microprocessor

Review microprocessors used in Arduino project. A first idea is the NINA-B3 series

Power system

The power system should be based on Lithium battery packs, with solar panel and solar charging capability. Sensors like SDI12 ones from Decagon require 5V, so a voltage regulator providing 5V is needed. These sensors also have the data line running in 5V, something to consider when connecting to the microprocessor.

Communication

Radio

Currently we run 2.4GHz xbee in mesh topology with success in Finse. Need to find the equivalent at lower frequency (840MHz) for long range communication but with mesh topology capabilities. Digi produces the radio chip SX868. It is packaged as surface mount, and there is no intent to be packaged as through hole by Digi, here email from Digi support:

Unfortunately there are no plans to release a through hole version of the XBee SX modules, but SMT pins 2-11/24-33 match TH pins1-10/11-20 so you can solder connectors onto those pins. to fit the SMT module into a TH mount. The only pins you will be missing are the ones used for SPI data.

Try finding other radio chip that can handle mesh topology. The ideal would be to make a socket like the one used for xbee, but also compatible with more radio like LoraWan if needed in the future.

4G

See current solution

Iridium

See current solution (Rockblock)

Resources and ideas

See the MayflyDIY system that incorporate many feature aligned with the system we want. Many hardware and software design worth investigating. The main problem is the microprocessor, which is the same as the waspmote one, so not large enough.
Arduino nano 33 BLE
university of Oregon Loom project
cuahsi meeting Sept 2019, about DIY and OS data collection

spectraphilic / wsn_hardware

New arduino based datalogger (full OS!) #7