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Sensor Fusion - rotation overshoot

Question asked by Mark Guzewski on Sep 18, 2018
Latest reply on Sep 20, 2018 by Lisette Paulina Lozano Gomez

I'm pretty new at this but I completed the on-line courses here and I'm getting a better understanding of what's involved. And I'm not sure of this post should be in the MCUXpresso area or in the Sensors area. Maybe both?


Anyway, I'm having a bit of an "out-of-the-box" issue and I wonder if someone can explain. The kit I'm using is the FRDM-K64F-AGM01.

  • The NXP Sensor Fusion Toolbox is installed. and running on my Windows PC.
  • I flashed the binary FSFK-K64F-AGM01-GL-NED.bin.
  • I selected the Gyro Stabilized Compass algorithm because that's kind of what we're doing.
  • Moving the unit around finally shows the magnetometer as calibrated.

And it seems to work, except for a couple of unexpected things happening.

Primarily troublesome is some kind of over-shoot when I rotate the unit. It responds fine, but when I stop rotation the model slowly rotates in the opposite direction for a few seconds to some stable point. I have attached a screen cap video of what I'm seeing. The quick rotations are because of me, and the slow rotations in the other direction happen all by themselves.

The other issue is the the model position drifts quite a bit over time. Our application requires that the thing maintain an accurate compass and tilt reading over extended periods (several hours, in fact). The tilt seems rock solid, but the compass will drift a couple of degrees per minute, and sometime exhibits a noticeable amount of jitter.

Is this some sort of calibration problem? Interference? Or is there something else I should be aware of?