FFT comparison between Copter 4.2 and 4.3

I conducted my first flights using Copter 4.3 today.

I compared the FFT results from my last flight on Copter 4.2 and my first on Copter 4.3.

Note that the change (improvement) required Mission Planner to change the scale of the Y-axis.

Copter 4.2

Copter 4.3

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Rescale both Gyro graphs to the same full scale (drag a window) and then compare them. It’s auto scaling to the rigid body mode at the low end which has little value. Drag the Y-axis scale to .01 on both.

I thought it might be interesting to have the original, un-attenuated plot for reference:

Now the plots of Copter 4.2 and 4.3 FFT filter processing:

The ACC0 plots show a whole order of magnitude lower amplitude of vibration. As such - I couldn’t put make their Y-axis scales the same.

I normalized the Y-axis scales for the GYRO plots.

The results are interesting - and something I didn’t notice at first.

While FFT does a wonderful job of filtering vibration detection, version 4.3 of copter (bottom graph) appears to let through more vibration than version 4.2 - and has two peaks.

I’m wondering if this is just because Copter 4.3’s FFT improvements simply reports more accurately.

I also thought it might be interesting to compare the processor load between Copter 4.2 and 4.3 - which of course entails a lot more than just the changes to FFT:

Copter 4.2 load:

Copter 4.3 load:

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