I was looking at the log of the third flight a bit more today using the online viewer, which is a bit easier to navigate and set up expressions.
There appears to be vibration in the accelerometer Y value, I’m not sure how significant this is to the EKF but it’s causing some jello in the HD video. Here is the moment where it switched into DCM briefly just before going berserk.
The gyro values at that time look clean.
There is something called VIBE, not sure how it is calculated but the Y axis again shows higher values.
Regarding the ‘rhythmic wobbles’ mentioned above, here is the gyroX and aileron together. They appear to be moving at exactly the same time which I would interpret as the gyro is causing the aileron. If the aileron output was causing the gyro movement I would expect at least a slight delay as the servo moves, air flow has to change etc.
The rhythmic wobbles were at a time in the flight when the accelerometer seemed to be less subject to vibration (probably lower motor throttle). Here are all the IMU values of a single ‘wobble’ event.
Only gyroX looks really out of place. Could a faulty gyro cause sudden oscillations like this maybe? I wonder why there were no problems at all in the second flight I did.
Here are some top-down screenshots of each flight.
Flight 1 seemed to hold things together relatively well, I could use RTL.
Flight 2 was basically flawless.
Flight 3 was chaos for most of the flight.
Side view of flight 2
Side view of flight 3