Identifying the Degree of Attentiveness of a Vehicle Occupant on the Basis of the Frequency Distribution of the Eye Opening Width

A method for operating a driver assistance system for a motor vehicle, the method comprising:

• in a course of a journey of the motor vehicle, triggering an assistance measure in dependence on a current degree of attentiveness of a vehicle occupant, wherein the current degree of attentiveness is determined by:
• performing a facial recognition of a face of the vehicle occupant, wherein the facial recognition comprises that at least one upper eye measuring point and at least one lower eye measuring point are assigned to at least one eye of the vehicle occupant,
• during the journey, acquiring a respective current eye opening width of the at least one eye of the vehicle occupant multiple times in a course of at least one observation interval as a distance between the at least one upper eye measuring point and the at least one lower eye measuring point,
• calculating a frequency distribution of the different eye opening widths for the at least one observation interval,
• providing comparison frequency distributions, wherein a known degree of attentiveness is assigned in each case to a respective comparison frequency distribution,
• from the comparison frequency distributions, determining one which has a predetermined degree of correspondence in at least one criterion with the calculated frequency distribution, and
• identifying the current degree of attentiveness as the degree of attentiveness assigned to the determined comparison frequency distribution.

A driver assistance system for a motor vehicle, wherein the driver assistance system is configured to determine a current degree of attentiveness of a vehicle occupant in a course of a journey of the motor vehicle and to trigger an assistance measure in dependence on the current degree of attentiveness, wherein the current degree of attentiveness is determined by:

• performing a facial recognition of a face of the vehicle occupant, wherein the facial recognition comprises that at least one upper eye measuring point and at least one lower eye measuring point are assigned to at least one eye of the vehicle occupant,
• during the journey, acquiring a respective current eye opening width of the at least one eye of the vehicle occupant multiple times in a course of at least one observation interval as a distance between the at least one upper eye measuring point and the at least one lower eye measuring point,
• calculating a frequency distribution of the different eye opening widths for the at least one observation interval,
• providing comparison frequency distributions, wherein a known degree of attentiveness is assigned in each case to a respective comparison frequency distribution,
• from the comparison frequency distributions, determining one which has a predetermined degree of correspondence in at least one criterion with the calculated frequency distribution, and
• identifying the current degree of attentiveness as the degree of attentiveness assigned to the determined comparison frequency distribution.