Method and apparatus for generating an indication of a level of vigilance of an individual

• US 7,435,227 B2
• Filed: 09/13/2004
• Issued: 10/14/2008
• Est. Priority Date: 09/13/2004
• Status: Expired due to Fees

• Current Assignee: Biocognisafe Technologies
• Original Assignee: Biocognisafe Technologies
• Inventors: Farbos, Bruno
• Primary Examiner(s): Hindenburg; Max
• Assistant Examiner(s): Hoekstra; Jeffrey G
• Application Number:
  US10/938,663
• Publication Number:
  US 20060055546A1
• Time in Patent Office: 1,492 Days
• Field of Search: 600/558, 340575-576
• US Class Current: 600/558
• CPC Class Codes: A61B 3/113 for determining or recording eye movement
• 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 40/19 Sensors therefor
• CPC Class Codes: G08B 21/06 indicating a condition of sleep, e.g. anti-dozing alarms

Abstract

A method and apparatus are disclosed for generating an indication of a level of vigilance of an individual using a gaze acquisition unit providing a gaze data stream of at least one eye of the individual, a processing unit receiving the gaze data stream and determining a level of vigilance.

Claims

1. A method for determining a level of vigilance of an individual, the method comprising:

acquiring a plurality of timely-spaced images of at least one eye of the individual over a given time period;

determining pupil positions of said at least one eye relative to a head of said individual at a plurality of instances in time;

extracting eye fixation positions over time and a moving frequency between the eye fixation positions from said pupil positions;

generating a gaze pattern indicative of a variation of the eye fixation positions over time;

comparing said gaze pattern to existing patterns, each one of said existing patterns being associated to a given level of vigilance; and

selecting a corresponding level of vigilance for said gaze pattern.

2. The method as claimed in claim 1, wherein said generating of said gaze pattern comprises using a given formulae over time for calculating said variation over time.

3. The method as claimed in claim 1, further comprising providing an information signal if said level of vigilance selected is lower than a given threshold.

4. The method as claimed in claim 3, wherein said information signal comprises an alarm signal.

5. The method as claimed in claim 1, wherein at least two consecutive levels of vigilance are selected over the given time period, and further comprising providing an indication of a variation between said at least two levels of vigilance.

6. The method as claimed in claim 5, further comprising providing an information signal if said variation exceeds a given threshold.

7. The method as claimed in claim 6, wherein said information signal comprises an alarm signal.

8. The method as claimed in claim 1, further comprising storing said level of vigilance selected with said gaze pattern generated.

9. The method as claimed in claim 1, wherein a corresponding black image and a corresponding white image are generated for each of said plurality of timely-spaced images, and further wherein said determining of said pupil positions of said at least one eye relative to said head of said individual comprises subtracting said corresponding white image to said corresponding black image.

10. The method as claimed in claim 1 wherein said comparing said gaze pattern to said existing patterns comprises performing an interpolation using more than one corresponding level of vigilance.