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IIHS Study on L2 driver attention

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Average guy who loves autonomous vehicles
Aug 3, 2017
IIHS did a study on driver attention with L2 driver assist systems. Probably not shocking, they found that people who were more familiar with the tech actually did pay attention more.

“Our data suggest that Level 2 driving automation has the potential to improve a driver’s situational awareness (SA) once he or she is familiar with the technology, although it does not guarantee it. Unfamiliar drivers, however, appear to have even more difficulty maintaining SA when using the system than when driving without it. On average, participants who were familiar with Level 2 systems showed the highest degree of SA about the bear when using the system, unfamiliar participants who drove with the system off had moderate SA, and unfamiliar participants who drove with the system on demonstrated the lowest SA,” the IIHS wrote.

Source: Level 2 systems like Tesla Autopilot can improve drivers’ attentiveness: IIHS study
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Reactions: powertoold
Sounds like a reasonable evaluation to me. I can only speak for myself, but my experience would be as they say. when driving on Autopilot, I supervise, looking ahead for problems. I am anticipating not reacting. Also, I am much more relaxed, less tired.
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Reactions: TresLA
Glad to see this study. Even though it's a small sample size (31 participants), it helps reconcile seemingly contradictory observations: some studies show that driver assistance systems reduce situational awareness, while others (e.g. Lex Fridman's MIT AVT study; IIHS and NHTSA studies on Autopilot) seem to imply the opposite.

As far as I know (and I may be wrong), the academic literature on situational awareness in driving has predominantly looked at what happens when you introduce a novel driving assistance system to drivers. By adding a third cohort of drivers with experience with pre-existing commercial driver assistance products, you account for the effect of human learning in the study design.
I fount it interesting that they were able to 'measure' the workload effort of learning FSD. To my mind, this helps to justify the opportunity for observation gains when the 'high frequency, low input' workload is reduced (lane keeping and follow distance in the main).
A new study based on MIT Advanced Vehicle Technology data found that Tesla Autopilot results in a noticeable decrease in driver attention when activated.

Tesla has been releasing quarterly “safety reports”, which they use to claim Tesla vehicles with Autopilot engaged have “close to 10x lower chances of being involved in an accident than the average car“.

However, this interpretation of the data has been disputed.

In most Tesla vehicles equipped with a version of Autopilot (1.0 to 3.0), the Autopilot features are mostly being used for highway driving. The same distinction is found for the “average vehicle”, which NHTSA’s overall crash data in the US is based on.

Accidents are more common on city roads and undivided roads than on the highway.