How to Collect Motor Speed Data

[TelloTubbie]

Does anyone know of a python code to get the drone's motor rpm (not flight speed) either directly or indirectly, such as a derivation from other parameters?

I'm using the DJI Tello EDU drone, and can't seem to figure out a way to do so. Any help would be greatly appreciated

 

[Hacky]

You could capture the noise with a microphone and apply a fourier transform to see the frequency spectrum. There are also some smartphone apps, that can do so.