BNO055 losing calibration

[simonenascivera]

Hi,

We are currently using a BNO055 as Absolute orientation sensor for navigation in an autonomous boat.
Even if we calibrate the sensor and upload the offsets at boot, the magnetometer keeps losing its calibration, sometimes with even 50-70° off from the calibrated orientation.
There's no metal object that could interfere in a meter from the sensor.

Is the sensor not suitable for our application? Are we doing something wrong?

Thank you in advance,

Simone Nascivera

[nicolaje]

But the magnetometer is the most hardcore sensor to calibrate (to my eyes).
When the magnetometer calibration status goes to zero because of external distortion, is it easier to get it back to status 3 than it would be calibrating from scratch?
In the author’s case, a robot boat is only able to perform planar motion, will it be able to recalibrate to 3 with only planar rotation ?

[Vincent]

I think you might be already see this video for BNO055 calibration. 

https://www.youtube.com/watch?v=Bw0WuAyGsnY

Even we support the fast magnetic calibraion,  the planar rotation is not able to achieve the calibration level 3 from level 0.  

How did you make the calibration?  if the major magnetic distortion is not coming from the lake,  you can try to calibrate the sensor nearby the final position to make the fusion lib know about the magnetic environment.  

In the other word,  when you do the system design,  you should keep the magnetic sensor away from the magnetic material as well as the big current lines.  

[weecabin]

I gave up trying to use it... It's not stable unless it's sitting perfectly still.