We have been playing around with some functionality of the BNO055, and decided to test out it's heading accuracy given a powerful external field (such as placing a permanent magnent) nearby, and to our surprise there was no change in the readings. We see that there is a functionality where it mitgates magnetic field distortion once it is calibrated, but it is still confuses us that, if something like a magnet is slowly brought close to the sensor from a significant distance, shouldn't there be some form of disturbance being detected? We like this functionality, but are skeptical of it's reliability. So, if I am completely incorrect with my assumptions, please correct me, and any explanation that can be given on this feature would be greatly appreciated.
Thanks!