I'd imagine 90% of the kalman filters out there are for 2 or maybe 3 dimensions, since the use case is mostly this, determining a position.
The filter fails is when there is not a single "true" answer to aim for, but there are many true answers. A position is clearly defined as long as it is not quantum physics.
The filter fails is when there is not a single "true" answer to aim for, but there are many true answers. A position is clearly defined as long as it is not quantum physics.