Level4

Level 4, in the SAE International framework for driving automation, denotes high automation where the vehicle can perform all tasks required to drive within a defined operating domain. In this level, the system can handle all aspects of the dynamic driving task without requiring constant human supervision in the designated area. Outside the defined domain, the system may request human intervention or the vehicle may disengage.

Vehicles capable of Level 4 automation rely on a combination of sensors, maps, and software to perceive the environment and make driving decisions. Redundancy in critical components, such as sensors, computing, and actuation, supports safe operation. The defined operating domain, or geofence, is determined by the manufacturer or operator and can vary by geography and time of day. Level 4 is distinguished from Level 3, which requires a human driver to be ready to take control, and from Level 5, which aims for full autonomy in all conditions and environments.

In practice, Level 4 deployments have appeared mainly as geofenced robotaxi or logistics vehicles in controlled areas. Operated by autonomous-driving companies or automakers, these services typically provide automated driving within a city or campus, with a safety driver or remote oversight depending on jurisdiction and system design. The technology continues to evolve, with ongoing work on perception accuracy, decision-making in edge cases, and regulatory frameworks shaping broader adoption.