Patent ID: 9384421
Filing Date: 2016-07-05
CPC Classification: G06K,G06T

Claim Text:
1. A method for ascertaining a drowsiness level of a driver in a vehicle, comprising: modifying, by a control unit of a driver assistance system having a processor, a predefined reference circadian curve characterizing a drowsiness level of the driver during a 24-hour period of a day, wherein the predefined reference circadian curve is modified as a function of an environmental brightness by (i) decreasing a current course of the circadian curve with respect to the reference circadian curve when an environmental brightness detected by a sensor exceeds a predefined brightness boundary value, and (ii) raising the current course of the circadian curve with respect to the reference circadian curve when the environmental brightness detected by the sensor lies below the predefined brightness boundary value; and ascertaining, by the control unit of the driver assistance system having the processor, the drowsiness level of the driver using the modified circadian curve for a specific point in time of the day.