Comment by Bluestrike2

4 hours ago

Disregarding the fact that NHTSA findings apparently contradict it (though that may just be a more recent change than the 2022 report), Tesla claims to use five seconds before a collision event as the threshold for their data reporting on their FSD marketing page:

> If FSD (Supervised) was active at any point within five seconds leading up to a collision event, Tesla considers the collision to have occurred with FSD (Supervised) engaged for purposes of calculating collision rates for the Vehicle Safety Report. This approach accounts for the time required for drivers to recognize potential hazards and take manual control of the vehicle. This calculation ensures that our reported collision rates for FSD (Supervised) capture not only collisions that occur while the system is actively controlling the vehicle, but also scenarios where a driver may disengage the system or where the system aborts on its own shortly before impact.[0]

In theory, that should more than cover the common perception-response times of around ~1 to 1.5 seconds used as a rule of thumb for most car accidents. But I'm quite curious what research has been done on the disengagement process as driver assistance systems return control to the driver and its impact on driver response times and their overall alertness.

If drivers trust the car to handle braking and steering for you, are we really going to see perception–response times that low, or have we changed the behavior being measured? Instead of timing a direct response to a stimulus, we’re now including the time required to re-engage their attention (even if they're nominally "paying attention"), transition to full control of the vehicle, and then react to the stimulus that they're now barreling down on.

For that matter, this approach is making the implicit assumption that pressing the brake pedal or turning the steering while is a sign of now-active control and awareness. Is it? Or could it just be a sort of instinctual reaction? I've been in the passenger seat when a driver has slammed on the brakes, only to find myself moving my right foot as if to hit an imaginary brake pedal even knowing I obviously wasn't the one driving. Hell, I remember my mom doing that back when I was learning to drive during normal braking.