51–60 of 191 posts
"As part of the calibration, the speed of sound is also a parameter which is optimized to obtain the best model of the system, which allows this whole procedure to act as a ridiculously overengineered thermometer." Reminds me of the electronics adage: "all sensors are temperature sensors, some measure other things as well."
Is there one saying “All electronic devices are smoke machines, some can compute too”?
Heck, train the model on the raw sensor data and you get the most awesome conference mics
I once did a project to do multilateration of bats (the flying mammal) using an array of 4 microphones arranged in a big Y shape on the ground. Using the time difference of arrival at the four microphones, we could find the positions of each bat that flew over the array, as well as identify the species. It was used for an environmental study to determine the impact of installing wind turbines. Fun times.
I had no idea they were mammals until this comment. I thought they were furry birds!
Earlier quoted context omitted.
Right, it gets even worse: Air pressure in not only altitude-dependent but fluctuates even at constant altitude. The pressure (altitude) dependence is comparatively weak, though.
one might say air pressure changes constantly as we speak.
I once did a project to do multilateration of bats (the flying mammal) using an array of 4 microphones arranged in a big Y shape on the ground. Using the time difference of arrival at the four microphones, we could find the positions of each bat that flew over the array, as well as identify the species. It was used for an environmental study to determine the impact of installing wind turbines. Fun times.
As opposed to?
What is the most practical application for this technology? Could you use it to pinpoint sounds coming from a car like a squeak?
I've always wanted this for videoconferencing room. A microphone array around the screen should be able to dynamically focus on the active talkers and cancel out background noise and echos to get much better sound quality that the muddy crap we usually get. If there were a speaker array around the screens too, you might be able to localize the audio for each person so that it seems like the sound is coming from where…
I once did a project to do multilateration of bats (the flying mammal) using an array of 4 microphones arranged in a big Y shape on the ground. Using the time difference of arrival at the four microphones, we could find the positions of each bat that flew over the array, as well as identify the species. It was used for an environmental study to determine the impact of installing wind turbines. Fun times.
> bats (the flying mammal) As opposed to?
"As part of the calibration, the speed of sound is also a parameter which is optimized to obtain the best model of the system, which allows this whole procedure to act as a ridiculously overengineered thermometer." Reminds me of the electronics adage: "all sensors are temperature sensors, some measure other things as well."
It does act as a thermometer, if and only if the altitude remains constant. The speed of sound fluctuates with both temperature and altitude
Putting that aside, in an ideal gas, the speed of sound depends on the composition of the gas and the temperature and, interestingly, does not depend on pressure, and pressure is the main way that the altitude would affect the speed of sound. So measuring the speed of sound in air actually makes for a pretty good thermometer.
Nice. It would be cool if this project could cleanly separate sources based on location. That would be a bit like a lightfield camera, where you can edit the focusing parameters after the image has already been taken, but now with sound. https://en.wikipedia.org/wiki/Light_field_camera