An automated vehicle automates some or all parts of the dynamic driving task, reducing or eliminating human inputs. SAE International Standard J3016 defines the automation capabilities of vehicles equipped with different levels of automation. This standard was updated in 2026. Level 0 vehicles have no automation features, even if they are equipped with advanced driver assistance systems (ADAS) that provide blind spot warnings or lane departure warnings. Level 1 – 2 vehicles incorporate more automation features, such as adaptive cruise control or steering assistance, although they require continuous driver supervision. Level 3 and above vehicles offer full automated driving, with Level 3 vehicles supporting full automation on a limited number of roadways under highly restrictive conditions. Level 5 vehicles offer full automation under all conditions — no human inputs are needed.

No vehicles with SAE Level 4 or 5 automation are on the market. Automakers are selling vehicles equipped with Level 2 and 3 automation systems, including Tesla Autopilot (Level 2), GM Super Cruise (Level 2), and Mercedes-Benz DRIVE PILOT (Level 3). DRIVE PILOT lets drivers take their hands off the steering wheel and eyes off the road while the system is engaged under certain conditions. Rollout has been very limited to date — the system can only be used in California and on a limited number of freeways in Nevada.

Automakers, commercial vehicle manufacturers, technology firms (e.g., Waymo), and transportation network companies (TNCs) are piloting SAE Level 4 and 5 systems. Waymo, for example, now offers its services in 15 US cities. Fully automated (Level 4), low-speed shuttles are being piloted in many states. They generally operate on looped routes, with testing focused on passenger experience and vehicle interactions with other motorists, pedestrians, and bicyclists. Low-speed shuttles could play an important role in solving the first mile/last mile challenge (e.g., getting passengers from transit stops to their final destinations, moving goods from a distribution hub to customers). 

University of Louisville researchers combined a driving simulation study with a statewide survey of drivers to document their perceptions of AVs and understand how they are likely to engage with AVs when they encounter them on roadways. Download the full report here. A two-page summary of survey findings is available here.