One of the units is described as smoothing the tracks to the micrometer level. I assume this is something like a camera array and tooling combo, where the tracks are imaged in 3D using the cameras, and abrupt changes in surface level are annotated, the grinding equipment is adjusted to the correct placement to remove the changes in surface level. There are a few cars on the unit, so I expect this process happens 2, 3, or even 5 times for a given segment of track.
Yes, even relatively low resolution cameras can provide enough information to track an object with high precision. For example, optical mice can provide high resolution tracking in 2D.
