I am having a problem with pitch measurements with Bosch BNO055 IMU. The device is rotated on a relatively stable rotating spindle and does a revolution on a circle around 10cm radius. It is upright in the current placement. Attached is my signal when I do harmonic oscillations on an arc of around 90 degrees.
The estimates I am getting are from the internal Kalman filter. We are using the sensor with RTIMULib and this test code:https://github.com/RPi-Distro/RTIMULib/blob/master/Linux/python/tests/Fusion.py
As far as I know, no preparations were done, including calibration.
I get very unusual discontinuities in pitch that do not look like warping at all. There are quite a few phenomena, like:
It doesn't seem symmetrical, the signal is not the same at the same point in both directions, which can be seen by asymmetrical peaks.
The jumps are sometimes from a to pi-a or -pi-a, but sometimes to a completely random value.
When the rotating plane is not horizontal, pitch stays small in some parts of the arc, while it changes rapidly in some other parts.
Can this be caused by the problematic orientation? Can this be "expected" in any scenario?