What system alerts a driver when it detects signs of fatigue?

Driver drowsiness detection is the system that alerts a driver when onboard technology detects signs of fatigue. It may monitor steering corrections, lane position, pedal inputs, trip duration, or the time since the last break, then display a warning recommending rest.

More advanced systems use an interior camera to analyze blinking, eye closure, gaze direction, head position, or facial movements. The system combines those clues because no single signal proves that a driver is tired. A warning can appear as a dashboard message, audible chime, steering-wheel vibration, or seat vibration.

This feature is not the same as lane-keeping assist. Lane keeping helps correct unintended drift, while drowsiness detection tries to identify reduced alertness. It also differs from driver-monitoring systems used for hands-off driving, although modern vehicles may combine both functions. The technology is an aid, not a guarantee: weather, sunglasses, poor lane markings, and individual driving habits can affect detection.