Building a turtle tracker

I have some students working on what is essentially a turtle-tracker. They’re going to take a Boron, GPS, and a H2O sensor, and track where some endangered turtles wander. The turtles are out of the water some of the time (and that’s when we’ll transmit data, on an hourly basis). Their current plan is to use a separate microcontroller to turn the Boron on and off to save power – the turtles are going to be tracked for several weeks and we can’t put a giant battery on them.

Does anybody have any suggestions as to how we might do this just using the Boron? Is there a really, really low power mode that might make this possible?

@mprogers, I have been thinking about your statement and I wanted to see if you can provide more information for clarity. These are not in order of importance.

  1. Aprox. size/shape of enclosure that would be appropriate for turtle? (effecting size of bat., etc.)
  2. Area of deployment - is this is area that is likely to have cellular LTE CAT-M1/NB1 when turtle surfaces?
  3. Expected depth of turtle dive (enclosure must be able to handle pressure without water intrusion)
  4. What is the purpose of the H20 sensor?
  5. How precise do the location coordinates need to be? Could the LAT/LONG of the cell tower that is being used suffice removing the need for GPS?
  6. Aprox. total distance turtles would be traveling (are we talking a few miles or 100 miles?)
    Typically how long/frequently are the turtles at water surface or out of the water?

I have a few ideas and there are some other resources that we could tag in, but it would be helpful to get as much information as you could provide so we have a deeper understanding of the project goal (whats the big picture goal) and project requirements and constraints.

Look forward to hearing from you.

Thanks for replying, backpacker87.

  1. 3x2", approximately
  2. It has cellular connectivity, yes
  3. Maybe 10 feet
  4. To detect when the turtle is underwater, so we won’t even think about transmitting
  5. They need exact coordinates
  6. A few miles - I believe they will always be in cellular surface.
  7. They are out of the water for hours at a time, sunning themselves.

HTH,

Michael

@mprogers, thank you for the additional information.

I have thought about your responses and have a few thoughts.

Another thread related to solar Boron projects that is waiting on the roll out of 1.5.0 final vs. the current 1.5.0-rc-1. Once this update is rolled out @Rftop has been leading the charge on providing excellent data regarding power use in sleep modes and power budgeting. I would watch this linked thread for new information.

I do not have any experience with the GPS module, so I cannot speak to power requirements of this, so maybe you can specify which one you are looking at. I can point you in the direction of a great tutorial written by @Moors7 that combines a Boron and a GPS featherwing. This article can definitely provide some inspiration, and this feather wing does have a documented power consumption.

Further thinking, knowing you are tight on space and power I started to kick around the idea of making the setup solar powered. You mentioned that the turtles will sun for hours, which I interpreted as a huge opportunity to leverage the turtles innate ability to seek and find awesome sun which in turn would lend itself to solar charging. I understand the desire to use the H2O sensor to detect absence of water (therefore at surface or out of water so attempting transmit makes sense); however, it was recently pointed out a Boron can wake from sleep when the panel begins to provide power. Also, inherently if the panel is getting sun there could be a likelihood the turtle is at surface or sunning (I don’t know if we are talking clear water or murky).

Lastly, the enclosure dimensions are going to be challenging. Knowing that any water intrusion could trash the whole setup enclosure selection is going to be key. I tried doing a bit of research finding something that was IP68 rated and plastic (so cellular signal can pass through) and everything was huge. I did find something like this enclosure but it is outside of your size constrains. Either way I don’t have a good answer for this but this could be a challenge.

The above is food for thought, what do you think?