Oh I see @Harold! That’s simpler than I thought. If it’s hot rods you want to photograph, you can set the trigger threshold to very high dB, thereby prevent most false triggers. And since the camera traps will be deployed roadside, probably with sufficient sun exposure and relatively easy to service, power consumption is probably not a problem. So I think what you’re suggesting is almost like a speed camera but acoustically instead of optically triggered…
Just curious: Do you think modding an Audiomoth into the acoustic trigger would help? Or just building something from scratch using the PH0645 microphone?
As for stereo camera traps…
Indeed, the motion sensors in camera traps are custom designed to have optimised trigger thresholds and detection angles. Several people I know have tried off the shelf PIR motion detectors, but they are usually waaaaaay too sensitive and you get a mountain of false-triggered images. So as a first step, I think building on an existing camera trap’s trigger would be better.
I did briefly consider setting up two camera traps side-by-side to obtain stereo images, but I think you suggested the critical point which is for both to be trigger simultaneously by the motion sensor on one camera trap.
In any case, I think the biggest core concept of both of our ideas (plus the BoomBox) is to tap into the triggering circuitry of existing camera traps. Right?
The closest thing I am aware for understanding that circuitry is this documentation of the BoomBox. Pages 12 & 13 links to Freaklabs’s documentation on how to tap into the motion sensors in 4 different models of camera traps. I’ve used camera traps extensively in the field, but don’t have the electronics expertise to fully understand if the information in that documentation is enough for us to plan next steps.
Are you or someone able to assess this documentation???
Excited to continue this conversation. I’m already learning lots from you @Harold!