I guess, like a lot of things Tesla are still developing, the speed sign recognition is basically just the first public version of that functionality. It's not reliable which is probably one reason why you have to tap the screen to set the AP limit rather than the car just doing it itself.
The part at 8:33 of this presentation explains some of the difficulties that they have with detecting "STOP" signs:
They can ask the cars to collect more examples to improve detection of things. So, presumably a similar situation exists for speed limit signs (e.g. need to better determine whether the sign applies to a side road, is the sign on the back of a truck, is it conditional based on the kind of vehicle or during school hours etc.)
It's a massive challenge, but it does look like they are aiming to be able to detect as many edge cases as possible (which they will absolutely need to do for FSD to actually drive itself.) And I agree it's quite insane to use AI to detect raindrops on the window, though I guess it means they don't have to interface with yet another kind of sensor? There's indications (from greentheonly on twitter) that they might even be developing their own parking sensors too so no doubt that will probably use some kind of AI as well!
The part at 8:33 of this presentation explains some of the difficulties that they have with detecting "STOP" signs:
They can ask the cars to collect more examples to improve detection of things. So, presumably a similar situation exists for speed limit signs (e.g. need to better determine whether the sign applies to a side road, is the sign on the back of a truck, is it conditional based on the kind of vehicle or during school hours etc.)
It's a massive challenge, but it does look like they are aiming to be able to detect as many edge cases as possible (which they will absolutely need to do for FSD to actually drive itself.) And I agree it's quite insane to use AI to detect raindrops on the window, though I guess it means they don't have to interface with yet another kind of sensor? There's indications (from greentheonly on twitter) that they might even be developing their own parking sensors too so no doubt that will probably use some kind of AI as well!