System and method for determining driver alertness

• US 9,041,789 B2
• Filed: 03/23/2012
• Issued: 05/26/2015
• Est. Priority Date: 03/25/2011
• Status: Active Grant

• Current Assignee: Joyson Safety Systems Acquisition, LLC
• Original Assignee: TK Holdings Incorporated (Ningbo Junsheng Investment Group Co., Ltd.)
• Inventors: Schamp, Gregory G.
• Primary Examiner(s): ELAHI, SHAN E
• Application Number:
  US13/428,365
• Publication Number:
  US 20120242819A1
• Time in Patent Office: 1,159 Days
• Field of Search: 348/78
• US Class Current: 348/78
• CPC Class Codes: A61B 5/163 by tracking eye movement, gaze, or pupil change
• CPC Class Codes: A61B 5/18 for vehicle drivers or machine operators
• CPC Class Codes: B60K 28/066 actuating a signalling device B60K28/063 takes precedence
• CPC Class Codes: G06V 20/597 Recognising the driver's state or behaviour, e.g. attention or drowsiness
• CPC Class Codes: G06V 40/161 Detection; Localisation; Normalisation
• CPC Class Codes: G08B 21/06 indicating a condition of sleep, e.g. anti-dozing alarms

Abstract

A driver alertness detection system includes an imaging unit configured to image an area in a vehicle compartment where a driver'"'"'s head is located; an image processing unit configured to receive the image from the imaging unit, and to determine positions of the driver'"'"'s head and eyes; and a warning unit configured to determine, based on the determined position of the driver'"'"'s head and eyes as output by the image processing unit, whether the driver is in an alert state or a non-alert state, and to output a warning to the driver when the driver is determined to be in the non-alert state.

Claims

1. A driver alertness detection system, comprising:

an imaging unit configured to image an area in a vehicle compartment of a vehicle where a driver'"'"'s head is located;

an image processing unit configured to receive the image from the imaging unit, and to determine positions of the driver'"'"'s head and eyes; and

a warning unit configured to determine, based on the determined position of the driver'"'"'s head and eyes as output by the image processing unit, whether the driver is in an alert state or a non-alert state, and to output a warning to the driver when the driver is determined to be in the non-alert state,

wherein the image processing unit determines that the driver is in the non-alert state when the determined position of the driver'"'"'s head is determined not to be within a predetermined driver head area region within the vehicle compartment or when the driver'"'"'s eyes are determined to be angled to an extent so as to not be viewing an area in front of the vehicle.

2. The driver alertness detection system according to claim 1, further comprising:

a disabling unit configured to temporarily disable the driver alertness detection system when a driver alertness signal is received.

3. The driver alertness detection system according to claim 2, wherein the driver alertness signal is output upon rotation of a steering wheel of the vehicle by at least a predetermined amount.

4. The driver alertness detection system according to claim 3, wherein the predetermined rotation amount corresponds to +/−

15 degrees from a center position of the steering wheel.

5. The driver alertness detection system according to claim 3, wherein, when the driver alertness signal is being output, the driver alertness signal is stopped from being output when the steering wheel of the vehicle is returned back to a substantially central position.

6. The driver alertness detection system according to claim 1, wherein the imaging unit comprises a monocular camera mounted in at least one of an instrument panel of the vehicle and a steering wheel of the vehicle.

7. The driver alertness detection system according to claim 1, wherein the warning unit determines that the driver is in the non-alert state when the determined position of the driver'"'"'s head as output by the image processing unit is not within a predetermined head location region for at least a first predetermined amount of time or when the determined positions of the driver'"'"'s eyes are not within a predetermined eye location region within the vehicle compartment for at least a second predetermined amount of time.

8. The driver alertness detection system according to claim 1, wherein the alert output by the warning unit corresponds to one of an in-dash buzzer or a vibration sent through a seat of the driver.

9. The driver alertness detection system according to claim 1, wherein the image processing unit comprises:

a first detection module that discriminates background structures from a silhouette of the driver and that computes rotation of the driver'"'"'s head and tilt/roll of the driver'"'"'s head; and

a second detection module that discriminates pitch of the driver'"'"'s head, computes control points from discernable facial structures of the driver'"'"'s head, and computes a matrix of inter-point metrics with respect to the driver'"'"'s head.

10. The driver alertness detection system according to claim 9, wherein the discernable facial structures comprise at least one of eyes, nostrils, and lips.

11. The driver alertness detection system according to claim 9, wherein the first and second detection modules utilize a Gouraud shading model to discriminate movement and position of the driver'"'"'s head.

12. A method of detecting driver alertness, comprising:

imaging an area in a vehicle compartment of a vehicle where a driver'"'"'s head is located, to obtain imaging data;

determining positions of the driver'"'"'s head and eyes based on the imaging data;

based on the determined position of the driver'"'"'s head and eyes, determining whether the driver is in an alert state or a non-alert state; and

outputting a warning to the driver when the driver is determined to be in the non-alert state,

wherein the driver is determined to be in the non-alert state when the determined position of the driver'"'"'s head is determined not to be within a predetermined driver head area region within the vehicle compartment or when the driver'"'"'s eyes are determined to be angled to an extent so as to not be viewing an area in front of the vehicle.

13. The method according to claim 12, further comprising:

temporarily disabling outputting of a warning when a driver alertness signal is received.

14. The method according to claim 13, further comprising:

detecting rotation of a steering wheel of the vehicle,

wherein the driver alertness signal is output upon rotation of the steering wheel of the vehicle by at least a predetermined amount.

15. The method according to claim 14, wherein the predetermined rotation amount corresponds to +/−

15 degrees from a center position of the steering wheel.

16. The method according to claim 14, wherein, when the driver alertness signal is being output, the driver alertness signal is stopped from being output when the steering wheel of the vehicle is returned back to a substantially central position.

17. The method according to claim 12, wherein the imaging data is obtained by a monocular camera mounted in at least one of an instrument panel of the vehicle and a steering wheel of the vehicle.

18. The method according to claim 12, wherein the driver is determined to be in the non-alert state when the determined position of the driver'"'"'s head as output by the image processing unit is not within a predetermined head location region for at least a first predetermined amount of time or when the determined positions of the driver'"'"'s eyes are not within a predetermined eye location region within the vehicle compartment for at least a second predetermined amount of time.

19. The method according to claim 12, wherein the alert corresponds to one of an in-dash buzzer or a vibration sent through a seat of the driver.

20. The method according to claim 12, wherein determining positions of the driver'"'"'s head comprises:

discriminating background structures from a silhouette of the driver, and computing rotation of the driver'"'"'s head and tilt/roll of the driver'"'"'s head; and

discriminating pitch of the driver'"'"'s head, computing control points from discernable facial structures of the driver'"'"'s head, and computing a matrix of inter-point metrics with respect to the driver'"'"'s head.

21. The method according to claim 20, wherein the discernable facial structures comprise at least one of eyes, nostrils, and lips.

22. A non-transitory computer readable medium storing computer program code that, when executed by a computer, causes the computer to perform the functions of:

imaging an area in a vehicle compartment of a vehicle where a driver'"'"'s head is located, to obtain imaging data;

determining positions of the driver'"'"'s head and eyes based on the imaging data;

determining, based on the determined position of the driver'"'"'s head and eyes, whether the driver is in an alert state or a non-alert state, wherein the driver is determined to be in the non-alert state when the determined position of the driver'"'"'s head is determined not to be within a predetermined driver head area region within the vehicle compartment or when the driver'"'"'s eyes are determined to be angled to an extent so as to not be viewing an area in front of the vehicle; and

outputting a warning to the driver when the driver is determined to be in the non-alert state.

23. The non-transitory computer readable medium according to claim 22, further causing the computer to perform the function of:

temporarily disabling outputting of a warning when a driver alertness signal is received.

24. The non-transitory computer readable medium according to claim 22, further causing the computer to perform the function of:

detecting rotation of a steering wheel of the vehicle,

wherein the driver alertness signal is output upon rotation of the steering wheel of the vehicle by at least a predetermined amount.

25. The non-transitory computer readable medium according to claim 24, wherein the predetermined rotation amount corresponds to +/−

15 degrees from a center position of the steering wheel.