Hi,
We are using a LSM6DSV16X unit to track pitch and roll in our product based on the quaternions reported by the unit's SFLP algorithm (High Accuracy ODR 120Hz)
During the operation and in what seem to be arbitrary times, the pitch and roll signals for such unit present some unexpected overshoot or oscillation (see below) before returning to the expected value.
The graph above shows the IMU pitch signal (purple) with the reading of an absolute encoder (blue) and both signals should be fairly similar. The roll signal below, although not compared to any other signal, should maintain the same oscilatory behavior that is seen before and after the anomaly (vertical axis in º). At the moment of the anomaly, no special movement happened that could have caused such readings.
We have other LSM6DSV16X units in the same usecase and we do not see such behavior as of now.
We were doubting whether this could be a calibration problem of the IMU? Is there any calibration procedure you recommend for these IMU units?
Could this maybe be somehow related to the limitation in the quaternion components variables stored in half precision floats? https://community.st.com/t5/mems-sensors/lsm6dsv-half-precision-error-at-180-degrees/td-p/628771
Thank you in advance,
Joan
