The issue isn't an instant loss of tracking, but gradual accumulation of quantization errors from subpixel-alignment of features and similar "drift" sources.
Don't get me wrong: mouse sensors are great for use in closed-loop control of business ends that don't require stiffness to work (compare to CNC mill chatter) like 3D printers or these handheld wood routers. You just want some way to anchor back to absolute coordinates or drift will be painful. Note mouse sensors are more accurately described as measuring visual rotation than translation: focal plane distance in gaming mice has a linear influence on reported distance/"effective dpi".
It shouldn't need to be fast to anchor the drift if you track the drift rate/scaling coefficients appropriately. Maybe they are using a mouse sensor there in bitmap camera mode, possibly rotating through their fleet of 4, together with a sufficiently-beefy computing system that keeps a map/atlas of the object's surface texture to find/match the captured bitmaps in.
Don't get me wrong: mouse sensors are great for use in closed-loop control of business ends that don't require stiffness to work (compare to CNC mill chatter) like 3D printers or these handheld wood routers. You just want some way to anchor back to absolute coordinates or drift will be painful. Note mouse sensors are more accurately described as measuring visual rotation than translation: focal plane distance in gaming mice has a linear influence on reported distance/"effective dpi".
It shouldn't need to be fast to anchor the drift if you track the drift rate/scaling coefficients appropriately. Maybe they are using a mouse sensor there in bitmap camera mode, possibly rotating through their fleet of 4, together with a sufficiently-beefy computing system that keeps a map/atlas of the object's surface texture to find/match the captured bitmaps in.