Fatigue detection system

What is the purpose of the ADAS fatigue detection system?

As soon as the vehicle is started up, the fatigue detection system analyzes the driver's typical behavior


To avoid possible accidents in situations in which the driver loses their focus at the wheel, either because they are fatigued or drowsy. The system recommends that they stop the vehicle until they are in optimal conditions to continue driving.

How it works

As soon as the vehicle is started up, the fatigue detection system analyzes the driver’s typical behavior, continuously evaluating the angular velocity of the steering wheel.

In the event of steering maneuvers that differ from the typical behavior of the driver, a visual, acoustic or sensory alarm is triggered, such as a vibration in the seat or steering wheel.

The rest-recommendation alert is activated after two hours of uninterrupted driving.

In high-end vehicles the system uses a camera that is directed at the driver to pick up the characteristics of the eyes, face and head, using those to detect driver fatigue, and this is offered as an option in this type of vehicle, although it is somewhat rare.


  • Steering wheel angle sensor to examine the micro-movements made by the driver throughout the journey.
  • Engine control unit to monitor how long it has been since the driver stopped the vehicle.
  • Driver information display (central console).

Collisions avoided

  • It reduces the number of accidents caused by a lack of concentration during long journeys or when the driver is not in optimal conditions for driving.


It could prevent 160 deaths a year due to drowsiness, according to the Spanish Foundation for Safety.

Use and limitations

  • The system is switched off when driving in urban areas because of the low speeds employed.
  • Adverse weather conditions such as strong side winds.


This system can be offered either as standard or as an optional package together with other systems depending on the manufacturer. The cost ranges from 300 to 800 € depending on the driving assistance systems included in the package.


It is mandatory from July 2022 for new approvals and from July 2024 for new vehicle registrations.