Patent attributes
A warning system includes an angle-detector, a curvature-detection-means, an alert-device, and a controller-circuit. The angle-detector indicates a steering-angle of a hand-wheel of a host-vehicle. The curvature-detection-means detects a curvature of a portion of a roadway traveled by the host-vehicle characterized as ahead of the host-vehicle. The alert-device is operable to alert an operator of the host-vehicle of driver-fatigue. The controller-circuit is in communication with the angle-detector, the curvature-detection-means, and the alert-device. The controller-circuit is configured to determine an average-steering-angle, determine an expected-steering-angle based on the curvature detected by the curvature-detection-means, determine a steering-angle-deviation based on the average-steering-angle and the expected-steering-angle, determine whether the steering-angle-deviation is greater than a predetermined deviation-threshold, determine a frequency of the steering-angle-deviation, and activate the alert-device when the frequency of the steering-angle-deviation exceeds a change-threshold.
