There may be a way to do this with a point-source light (a focused LED, or maybe an appropriate laser), and a diffraction grating (which may be already exist in stage lighting world). Such that when the parts move relative to eachother, the projected dots move across the car's interior.

In terms of controls, it seems likely that it should seek to emulate whatever it is that goes on inside the inner ear, so that the input from our eyes better-matches the input from our ears.

I don't know how Apple's dots work (and I don't think my singular iOS device is new enough to try), but if they only respond to acceleration, then doing it this way should help establish mechanical limits: The acceleration (in any direction) of a car is finite, and always returns to zero.