Unobtrusive driver drowsiness detection system and method
First Claim
1. A system for determining whether a driver of a vehicle is drowsy, the system comprising:
- steering wheel sensor configured to generate a steering wheel signal;
a processor configured to extract at least one feature of the steering wheel signal by identifying a pair of consecutive zero-crossings where the signal values are zero, determine a distance between the pair of consecutive zero-crossings, repeat the identifying and distance determining steps for a plurality of pairs of consecutive zero-crossings, determine a standard deviation of the distances, determine whether the driver is drowsy based on the standard deviation, and generate an alarm signal in response to determining that the driver is drowsy, wherein the processor is more likely to determine that the driver is drowsy as the standard deviation increases relative to a normal standard deviation for the driver; and
,an alarm device configured to indicate that the driver is drowsy, or a safety mechanism for controlling the vehicle, wherein the alarm device or safety mechanism receives the alarm signal from said processor and is activated in response to the alarm signal.
1 Assignment
0 Petitions
Accused Products
Abstract
A drowsiness detection system and method uses Empirical Mode Decomposition (EMD) signal processing to detect whether a vehicle driver is drowsy. The system uses a decomposed component of the steering wheel signal to extract specific features representing the steering control degradation phases. The system classifies the measured features into alert or drowsy state. The detection system is independent of the road geometry and automatically compensates steering control performance variability between drivers. The system is accurate in detecting the drowsy periods and drowsy-related lane departures. The detection system is unobtrusive and can be applied on-line.
-
Citations
23 Claims
-
1. A system for determining whether a driver of a vehicle is drowsy, the system comprising:
-
steering wheel sensor configured to generate a steering wheel signal; a processor configured to extract at least one feature of the steering wheel signal by identifying a pair of consecutive zero-crossings where the signal values are zero, determine a distance between the pair of consecutive zero-crossings, repeat the identifying and distance determining steps for a plurality of pairs of consecutive zero-crossings, determine a standard deviation of the distances, determine whether the driver is drowsy based on the standard deviation, and generate an alarm signal in response to determining that the driver is drowsy, wherein the processor is more likely to determine that the driver is drowsy as the standard deviation increases relative to a normal standard deviation for the driver; and
,an alarm device configured to indicate that the driver is drowsy, or a safety mechanism for controlling the vehicle, wherein the alarm device or safety mechanism receives the alarm signal from said processor and is activated in response to the alarm signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 20, 21, 22)
-
-
16. A system for determining whether a driver of a vehicle is drowsy, the system comprising:
-
a steering wheel sensor for generating a steering wheel angle signal; a processor configured to window the steering wheel signal by dividing the steering wheel signal into a plurality of consecutive sequences of data frames, each data frame having steering wheel data that overlaps with an adjacent data frame; said processor further configured to decompose the windowed steering wheel data based on an empirical mode decomposition intrinsic mode function 1; said processor further configured to determine whether the driver is drowsy based on said decomposed steering wheel data, and generating an alarm signal; and an alarm device for indicating that the driver is drowsy, or a safety mechanism for controlling the vehicle, wherein the alarm device or safety mechanism receives the alarm signal from said processor and is activated in response to the alarm signal. - View Dependent Claims (17, 18, 19)
-
-
23. A system for determining whether a driver of a vehicle is drowsy, the system comprising:
-
a steering wheel sensor configured to generate a steering wheel signal; a processor configured to window the steering wheel signal by dividing the steering wheel signal into a plurality of consecutive sequences of data frames, each data frame having steering wheel data that overlaps with adjacent data frames, said processor further configured to identify a maximum extrema value and a minimum extrema value in the windowed steering wheel signal, determine a standard deviation for the maximum and minimum extrema values, determine whether the driver is drowsy based on the standard deviation, and generate an alarm signal in response to determining that the driver is drowsy, wherein the processor is more likely to determine that the driver is drowsy as the standard deviation increases relative to a normal standard deviation for the driver; and
,an alarm device configured to indicate that the driver is drowsy, or a safety mechanism for controlling the vehicle, wherein the alarm device or safety mechanism receives the alarm signal from said processor and is activated in response to the alarm signal.
-
Specification