> trapping and using dental floss to tie tracking devices to the hornets
What? That seems crazy (and cool) to be able to create a tracking device light enough for a hornet to fly and still have enough battery to transmit even a periodic chirp.
What? That seems crazy (and cool) to be able to create a tracking device light enough for a hornet to fly and still have enough battery to transmit even a periodic chirp.
This one is 3x11mm and weighs 0.15g;
https://atstrack.com/tracking-products/transmitters/product-...
It says it's light activated. So likely they've put a tiny light sensor in it that the microcontroller polls occasionally during the lowest power mode. That might be a tiny solar panel too. But using that to electrically drive an electronic power switch is tricky if you don't have the budget for a custom ASIC; if you don't have that budget, you'll add a decent amount of weight in a device that tiny.
Honestly, I'm not at all surprised that they've chosen to accept a short shelf life instead. It's pretty remarkable that they can squeeze that much functionality into a 11mm long by 3.5mm diameter cylinder.
All of this would add weight and size, and those trackers are really small and really lightweight. Judging by the photos, the battery is just hard wired to the circuit, and the whole thing is encapsulated with a thin layer of epoxy for waterproofing. That's by far the cheapest, easiest, and most reliable way to build something as lightweight as possible.
I wonder why its not just two interconnecting cylinders (using a tiny gasket) that you push together with thumb/finger when you want to activate/power the device.
Given that there would have been some serious engineering to think through the design there must have been trade-offs that I'm not considering though.