Vibration Levels and "Dangerous" Frequency Ranges

Hi, posted this in the Cube Facebook Group but did not get an answer, so I thought I would try here too. I am doing some vibration tests on one of my fixed wing aircraft and I would like to know more about the “dangerous” frequencies for Cube. There was a useful thread here on the Ardupilot forum, started by Philip Rowse, which was actually a competition, but I don’t think it was concluded as to who provided the “best” answer to his questions. One poster “Charlie_R” seemed to have a thorough understanding, and gave some very detailed explanations. Can those be taken as the truth? Specifically, I am interested in confirmation about the Cube’s resonant frequency for the two damped accelerometers, which is claimed to be 60Hz. That would imply that harmonics, (ie. 15, 30 and 60Hz) would be the “dangerous” frequencies. Is that correct?

On one of my particular aircraft, I am seeing accelerations of 40 m/s/s on average, which the Ardupilot Wiki says is high, however, this is only occurring at a very specific frequency of around 83Hz. The vibration is much lower (around 10 to 20m/s/s) for frequencies above and below the 83Hz.

So, do I need to be concerned?


Arduplane has had the Dynamic Notch Filter in since 4.1 (we’ll after that linked post) with improvements in later rev’s (ESC Telemetry RPM and FFT referenced notch). All features that have been routinely configured in Copter for awhile. I think you can address any concern with these features.