Patent ID: 8742936

Claim:
A method for detecting when a driver of a vehicle becomes inattentive by sensing steering wheel angle signals generated by a steering wheel angle sensor of the vehicle, comprising: determining a driver-specific warning triggering threshold, sensing a start of a steering inactivity phase in which the steering wheel angle is deflected within a predetermined deflection range, sensing an end of the steering inactivity phase when the steering wheel angle is outside of a predefined deflection angle, and determining a steering inactivity phase duration, determining a characteristic of a steering action acquired by the end of the steering inactivity phase, logically combining the steering inactivity phase duration and the characteristic of the steering action acquired at the end of the steering inactivity phase only when the steering inactivity phase duration is longer than a predetermined minimum duration and the characteristic of the steering action exceeds a predetermined threshold to provide a logic combination result, determining driver inattentiveness to exist when the logic combination result exceeds said driver-specific warning triggering threshold, repeating the above sensing steps, the determining a steering inactivity phase duration step, the determining a characteristic step, the logically combining step, and the determining driver inattentiveness step, collecting and storing a plurality of the logic combination results, and assigning a weighting factor to each logic combination result to provide weighted logic combination results, wherein the assigned weighting factor represents a respective driving situation of the vehicle or a current deflection of the driver in each case at a time to which each logic combination result refers, determining a final logic combination result from the weighted logic combination results to update said driver-specific warning triggering threshold, determining driver inattentiveness to exist when the final logic combination result exceeds said updated driver-specific warning triggering threshold, and outputting a warning message to the driver when driver inattentiveness is determined to exist.