Sound travels, what, 30 centimeters a ms?
Bluetooth/wifi is good for at least a few meters, and should have latency of around a ms. Should be pretty easy to synchronize via that.
Bluetooth/wifi is good for at least a few meters, and should have latency of around a ms. Should be pretty easy to synchronize via that.
Amusingly, data collection would be easier with analog technology. Get some VHS walkie-talkies, and, at the base station, feed all the channels into a multitrack tape recorder like musicians use. No sync problems.
I guess this is complicated by the fact that the speed of sound through the ground is ~6km/s. Rather faster than the speed of sound through the air. Multiplying those errors by 20... but 200 meters of error isn't that bad. A powerful local network with no latency would then be enough to isolate further.
Anyways, turns out that you can get gps time on androids, so this should be solvable with much better latency https://stackoverflow.com/questions/7017069/gps-time-in-andr...
It’s pretty easy to do with NTP synced devices. I’m lucky enough to have a fleet of devices sync with GPS and the PPS signal. It’s pretty amazing to/fun to do latency tests, you grab a time stamp and ship it to far side and time stamp the arrival. Voila single direction latency measurements.