Vibration in Stabilize mode

I have switched out the pixhawk and raspberry-pi with a Navigator and now the sub is shaking in Stabilize and depth hold mode. I have tried to tune the ROV in PID-tuning but then I get other issues, one issue is that if you turn the ROV 180 degres it doesnt end up level. Also if the ROV is tilted, it doesnt go back to the same angle if you drive it around.

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Hi @LarsMR, sorry to hear that you are having trouble with it.

  • Is this a BlueROV2? Can you share a picture of your build and electronics tray?
  • Have you performed a calibration of the gyro, accelerometer and magnetometer?
  • Can you share a short video of this behavior paired with the log data captured during the video?
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Hi, I work with Lars, and I am the author of this post regarding the same vehicle:

To answer your questions:

Is this a BlueROV2? Can you share a picture of your build and electronics tray?

No, Its a custom vehicle with the heavy frame configuration, and running on Ardusub. We have used it for several years with the pixhawk1 without these complications. The only change made was switching the pixhawk1 for a Navigator. The Navigator is fastened securely within our housing, and mounting orientation is taken into account.

Have you performed a calibration of the gyro, accelerometer and magnetometer?

Yes, however I am noticing that the Accelerometer does not show up under the “summary” in QGC.
qgc_summary
There is also no readings accelerometer nor gyro readings on the SCALED_IMU2 mavlink message, but there is gyro on RAW_IMU. The attitude messages seems fine. I do not know if this can cause our issues.
scaled_imu2
raw_imu

Can you share a short video of this behavior paired with the log data 4 captured during the video?

It was kind of hard to capture on film, but you can see and hear the vibration during the ascent of the vehicle.
Video showing vibration

Log files:
00000022.BIN (1.2 MB)
00000020.BIN (5.7 MB)
00000021.BIN (160 KB)

Thanks for helping us.

Kristian

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Hi

When tilting the vehicle and thrusting sideways it seams to follow a curved path. Have you tried the Navigator and BlueOS in a 8 thruster configuration?

Hi again,
we are able to eliminate the vibration issue by tuning the PID-controller. However, the issue mentioned in
Weird behavior after change to Navigator from pixhawk1 - #2 by krisaue still remains. I updated my post there, but can do it here also.

The movement of yawing while having a pitch angle seems to have changed after moving from a pixhawk1 with companion software to Navigator with BlueOs.

This was the movement the vehicle made when yawing with a pitch angle with the pixhawk1:
Rotate_Global_Axis

This is the new movement when yawing with a pitch angle using the Navigator:
Rotate_Local_Axis

Is there a parameter change that causes this or may it be a result of something else?

Kristian