Good toolkit to have around. Recently used it to verify the true RPM of a system (using the accelerometer spectrum tool) against its control loop implementation.
One of my kids has science project due each quarter in school, and this is our go-to app. We’ve measured acceleration in an elevator, sound attenuation of an audio source in a small vacuum chamber, and the Doppler effect. The app makes it easy to capture and export the data points to make graphs. I highly recommend this even just to play around with.
I dont know if others have experienced this, but there's always that one kid in the science fair who builds like an entire satellite dish or something waaaaaay over the top.
I don't necessarily have anything against it, it's just a pattern I've recognized.
My parents have a sound bowl, and I wanted to know the resonance frequency. Took an audio spectrum, zoomed in on the first peak, read the frequency (iirc it was around 208 Hz).
The coolest thing I ever did with that was finding wires in a friends wall - we needed to drill a hole and it was unclear whether the wires went up (problem) or right from the outlet. I didn't have a cable finder on hand but did have the epiphany to put a large load on the outlet (we used a kettle, a hairdryer would also work, just needs a lot of watts) and use the Fourier transform magnet spectrum to find the 50 Hz grid frequency in the wall. Worked beautifully.
Sadly, since most smartphone magnetometers seem to have a sample rate of 100/s, this will not be applicable to Americans and everyone else with a 60 Hz grid frequency, the 50 Hz were already at the Nyquist–Shannon limit.
If your sample rate is 100 Hz you would usually apply analog lowpass filtering at around 40 Hz, well below Nyquist. But with enough load on the line, since no filter has perfect attenuation in the stop band…
I've had great fun using Phyphox to visualise my hand getting closer/farther from my phone based on the presence of my magnet implant. So many cool little things the app can visualise and measure, especially when used it creative ways.
I think there's loads of scope to use phone cameras as dataloggers too, especially for older equipment that doesn't have an easy way to connect/export the data.
(I've been meaning for ages to write a piece of software that's able to extract change over time data from a video of a 7 segment display, like on a balance or a digital thermometer or something)
Coincidentally, I downloaded the app yesterday. In 10 min, in my mitchen, I found g ~ 9.7 m/^2 using a cheap kitchen spring scale and the accelerometer (without g) sensor. Quality app.
Damn that's very impressive - for a long time Android had a lot of hopeless accelrometer, audio scope, etc apps, and it's always been hard to add your own stuff to it.
Sounds very very neat!
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[ 0.19 ms ] story [ 49.3 ms ] threadIn Germany phyphox is quite popular in physics education.
However on android the sampling rate of the acceleration sensor is limited to 50/s. At least if you install through the official app store.
[1] https://iopscience.iop.org/article/10.1088/1361-6552/aac05e
I dont know if others have experienced this, but there's always that one kid in the science fair who builds like an entire satellite dish or something waaaaaay over the top.
I don't necessarily have anything against it, it's just a pattern I've recognized.
The interface is more polished, but the information is less technical than Phyphox (as the app is geared towards being a survival toolkit).
[0] https://github.com/kylecorry31/Trail-Sense
My parents have a sound bowl, and I wanted to know the resonance frequency. Took an audio spectrum, zoomed in on the first peak, read the frequency (iirc it was around 208 Hz).
Sadly, since most smartphone magnetometers seem to have a sample rate of 100/s, this will not be applicable to Americans and everyone else with a 60 Hz grid frequency, the 50 Hz were already at the Nyquist–Shannon limit.
(I've been meaning for ages to write a piece of software that's able to extract change over time data from a video of a 7 segment display, like on a balance or a digital thermometer or something)
https://github.com/arturaugusto/display_ocr?tab=readme-ov-fi... and https://github.com/Shreeshrii/tessdata_ssd which may be more fitting (or more modern?) for your use case. Lots has changed in ~15 years!