71–80 of 191 posts
If somebody wants to play around with Zynq 7010's - have a look at the EBAZ4205 board. They can be bought from Aliexpress (20-30€). These are former Bitcoin Mining controllers. Some people reverse engineered the entire thing. It can be found in GitHub. And there's an adapter plate available for getting to the GPIOs. For a less complex entry there are also Chinese FPGAs ("Sipeed" boards which use a GoWin FPGA. They ar…
"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”?
Earlier quoted context omitted.
I love these kind of inadvertent measurements. One of my favorite examples is that a sufficiently accurate IMU can get you relatively accurate longitude measurements from the Coriolis effect.
Slight correction, latitude, not longitude. The earth’s surface closer to the poles has less distance to travel for any rotation than the surface closer to the equator. As a result the inertial navigation systems of long distance systems must be adjusted. Iirc, this is also the case for artillery firing computations. https://www.oxts.com/blog/going-round-circles-earth-rotation... https://www.britannica.com/science/la…
Earlier quoted context omitted.
I love these kind of inadvertent measurements. One of my favorite examples is that a sufficiently accurate IMU can get you relatively accurate longitude measurements from the Coriolis effect.
Is that the same thing where a flat-earther tried to measure something with an expensive laser gyro and kept finding that Earth was rotating?
Thought experiment: if I zeroed my IMU at the North pole and traveled in a straight line away from the pole along longitude zero, following the guidance of the IMU. By the time I got to 45° latitude I’d be traveling Westward at 1,180 kph (.95 Mach) to keep the IMU at zero.
I understand that ICS-52000 is a relatively low cost ($2/100pcs) and there are even breakout boards available with 4 microphones, which can be chained to 8 or 16, like https://www.cdiweb.com/datasheets/notwired/ds-nw-aud-ics5200...
Then you can take Jetson (or any I2S capable hardware with DSP or GPU on it) and chain 16 microphones per I2S port. It would seem a lot easier to assemble and probgam, if comared to FPGA setup.
Earlier quoted context omitted.
It does act as a thermometer, if and only if the altitude remains constant. The speed of sound fluctuates with both temperature and altitude
I’m not sure how the speed of sound could depend on altitude, even in principle. The air doesn’t know where it is! 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 pr…
https://courses.lumenlearning.com/suny-physics/chapter/13-3-...
I would love to see this come to our various mobile devices in a nicely packaged form. I think part of what is holding back assistants, universal-translators, etc, is poor audio. Both reducing noise and being able to detect direction has a huge potential to help (I want to live-translate a group conversation around a dining table, for example). Firstly it would be great if my phone + headphones could combine the micr…
For the hard of hearing like me the killer application would be live transcription in a noisy setting like a meetup or party, with source separation and grouping of speech from different speakers. Could be life-changing. (Android's Live Transcribe is very good now but doesn't even try to separate which words are from different speakers.)
https://assets.amazon.science/da/c2/71f5f9fa49f585a4616e49d5...
"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."
I love these kind of inadvertent measurements. One of my favorite examples is that a sufficiently accurate IMU can get you relatively accurate longitude measurements from the Coriolis effect.