VIGILANCE DETECTION METHOD AND APPARATUS

• US 20160343229A1
• Filed: 05/18/2015
• Published: 11/24/2016
• Est. Priority Date: 05/18/2015
• Status: Abandoned Application

• Current Assignee: Frank Colony, George Martin Hutchinson
• Original Assignee: Frank Colony, George Martin Hutchinson
• Inventors: Colony, Frank, Hutchinson, George Martin
• Application Number:
  US14/715,512
• Publication Number:
  US 20160343229A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06V 20/597 Recognising the driver's state or behaviour, e.g. attention or drowsiness
• CPC Class Codes: G06V 40/176 Dynamic expression
• CPC Class Codes: G06V 40/193 Preprocessing; Feature extraction
• CPC Class Codes: G06V 40/20 Movements or behaviour, e.g. gesture recognition recognition of facial expressions G06V40/16
• CPC Class Codes: G08B 21/06 indicating a condition of sleep, e.g. anti-dozing alarms

Abstract

An apparatus and method for calculating a real-time cognitive capacity score based on physical measurements of a user operating in a mentally fatiguing environment is provided. The cognitive capacity score is based primarily on measurements of various eye-blink variables, supported by other objective and subjective measures.

Claims

1. A cognitive capacity detection apparatus comprising:

an optical device configured to obtain a sequence of images of an eye of a subject and a facial region of said subject proximate said eye;

a processor in data communication with said optical device;

wherein said processor is adapted to analyze said sequence of images to determine a duration of a partially closed period when said eye is partially closed during an eye blink;

wherein said processor is adapted to calculate a rate of closure of said eye blink from said partially closed period;

wherein said processor is adapted to perform a calculation a rate of closure difference between said rate of closure and a rate of closure threshold value; and

an alert system in data communication with said processor and adapted to indicate when said rate of closure difference indicates an increase in mental fatigue.

2. The apparatus as in claim 1, wherein said rate of closure threshold value is obtained from said subject during an alert rested phase.

3. The apparatus as in claim 1, wherein said processor is adapted to analyze said sequence of images to determine the duration an open period when said eye is open, a closed period when said eye is closed, and calculate a ratio of said open period and said closed period and calculate a ratio difference between said ratio and a ratio threshold value.

4. The apparatus as in claim 3, said alert system further adapted to indicate when said ratio difference indicates an increase in mental fatigue.

5. The apparatus as in claim 3, wherein said ratio threshold value is obtained from said subject during an alert rested phase.

6. The apparatus as in claim 1, further comprising a user input device in data communication with said processor and adapted to receive feedback from said subject regarding said subject'"'"'s self assessment of mental fatigue.

7. The apparatus as in claim 6, wherein said processor is adapted to alter said calculation based on said feedback.

8. The apparatus as in claim 1, wherein said processor, said optical device, and said alert system are affixed to a frame of eyewear.

9. The apparatus as in claim 1, wherein said processor, said optical device, and said alert system are components of a smartphone.

10. The apparatus as in claim 1, wherein said optical device is adapted to detect light in any of visible, infrared, or ultraviolet spectrum ranges or any combination thereof.

11. The apparatus as in claim 1, further comprising a light source positioned to illuminate said eye and said facial region.

12. The apparatus as in claim 1, further comprising an accelerometer removably affixed to a head of said subject, configured to detect head movements of said subject, and in data communication with said processor.

13. A vigilance prediction apparatus comprising:

an imaging device configured to obtain a sequence of images of an eye of a subject and a facial region of said subject proximate said eye;

a processor in data communication with said imaging device;

wherein said processor is adapted to analyze said sequence of images to determine the duration of a partially closed period when said eye is partially closed during an eye blink;

wherein said processor is adapted to calculate a rate of closure of said eye blink from said partially closed period;

wherein said processor is adapted to perform a calculation a rate of closure difference between said rate of closure and a rate of closure threshold value; and

an alert system in data communication with said processor and adapted to indicate when said rate of closure difference indicates that an increase in mental fatigue will occur within a set time period.

14. The apparatus as in claim 13, wherein said rate of closure threshold value is obtained from said subject during an alert rested phase.

15. The apparatus as in claim 13, wherein said processor is adapted to analyze said sequence of images to determine the duration an open period when said eye is open, a closed period when said eye is closed, and calculate a ratio of said open period and said closed period and calculate a ratio difference between said ratio and a ratio threshold value.

16. A method of determining onset of mental fatigue in a subject, the method comprising:

acquiring a series of images with an optical device of an eye and a facial region of a subject, the facial region proximate said eye;

measuring from said series of images a duration of a partially closed period when said eye is partially closed during an eye blink;

calculating a rate of closure of said eye blink based on said partially closed period;

calculating a rate of closure difference between said rate of closure and a rate of closure threshold value; and

enunciating an alert when said rate of closure difference is indicative of an increase in mental fatigue.

17. The method of claim 16, the method further comprising:

measuring from said series of images the duration of an open period when said eye is open, a closed period when said eye is closed;

calculating a ratio of said open and said close period;

calculating a ratio difference between said ratio and a ratio threshold value; and

enunciating an alert when any of said ratio difference, said rate of closure difference, or a combination of these differences is indicative of an increase in mental fatigue.

19. The method of claim 16, the method further comprising:

measuring from said series of images the duration of an open period when said eye is open, a closed period when said eye is closed;

calculating a ratio of said open and said close period;

calculating a ratio difference between said ratio and a ratio threshold value; and

enunciating an alert when any of said ratio difference, said rate of closure difference, or a combination of these differences indicates that an increase in mental fatigue will occur within a time period.

18. A method of predicting an onset of mental fatigue in a subject, the method comprising:

acquiring a series of images with an optical device of an eye and a facial region of a subject, the facial region proximate said eye;

measuring from said series of images a duration of a partially closed period when said eye is partially closed during an eye blink;

calculating a rate of closure of said eye blink based on said partially closed period;

calculating a rate of closure difference between said rate of closure and a rate of closure threshold value; and

enunciating an alert when said rate of closure difference indicates that an increase in mental fatigue will occur within a time period.

20. The method of claim 18 further comprising acquiring said series of images prior to conducting an activity.