We're so excited to celebrate WILDLABS' new editorial series, Technical Difficulties, an exploration of conservation tech challenges, failures, and lessons learned.
In the spirit of learning from failures and challenges in conservation tech, we've created this thread to give you a space to discuss your own experiences. Please feel free to talk about your own lessons learned, share advice, discuss the series and how the articles relate to your own work, and even ask for help with challenges you're currently facing.
We hope this will be an active, ongoing, and supportive space on WILDLABS to open up this conversation and help us express the value of failure together as a community.
Looking forward to learning with all of you!
2 January 2022 11:49pm
I'm not sure if this is the best place for this (particularly given that nobody else seems to have taken up the invitation in the OP).
I am having problems with my animal carried audio recorders.
The plan. My aim with this project is to record the feeding sounds of Koalas so as to quantify and qualify what and when the koalas are eating.
The set-up. I am recording continuous audio to micro SD card using audio boards pulled from Russian assembled Laboratory2 voice recorders (Soroka 17e). These boards have a low current draw (<1.7 mA) which allows me to power them with Lithium thionyl chloride batteries for up to 6 months using a 26500 sized cell. I have housed the battery and audio board in a PLA 3D printed collar mounted housing. Because the board relies on a micro-SD card socket and the MEMS microphone is also on the board thumbnail sized board, I cannot encase the electronics in resin. The case is exposed to the same environment as the koala although low and high temperatures are probably avoided to some degree by contact with the koala. The case has been tested as "water proof" when freshly assembled by weighing it down in a bucket of water for a day (without the electronics inside).
The problem. So far none of my deployed units have run for the expected time with the audio board swiching off prematurely, mostly due to corrosion causing an error in the electronics. In at least one case the audio membrane on the case was damaged which had allowed moisture to enter the case, but in some instances, there does not appear to have been any moisture intrusion to the case.
This had me wondering if the damaging environment was in the case itself. I have read that there is some potential outgassing from Lithium Thionyl Chloride cells although it is not entirely clear what the offending gas is. Also I guess it is possible that PLA (Poly-lactic Acid) plastics release a corrosive substance as they cure/degrade.
Any guidance or help that anyone can give me with this would be greatly appreciated.