BIOLOGICAL BODY STATE ASSESSMENT DEVICE

• US 20130021463A1
• Filed: 04/05/2010
• Published: 01/24/2013
• Est. Priority Date: 04/05/2010
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Hatakeyama, Yoshiyuki
• Granted Patent: US 8,866,896 B2
• Time in Patent Office: Days
• US Class Current: 348/78
• CPC Class Codes: A61B 5/11 Measuring movement of the entire body or parts thereof, e.g. head or hand tremor, mobility of a limb for measuring pulse A61B5/02 ;A61B5/1038 takes precedence; motion detection to correct for motion artifacts in physiological signals A61B5/721
• CPC Class Codes: A61B 5/1103 Detecting eye twinkling
• CPC Class Codes: A61B 5/1128 using image analysis A61B5/1127 takes precedence
• CPC Class Codes: A61B 5/18 for vehicle drivers or machine operators
• CPC Class Codes: A61B 5/7275 Determining trends in physiological measurement data; Predicting development of a medical condition based on physiological measurements, e.g. determining a risk factor
• CPC Class Codes: A61B 5/746 Alarms related to a physiological condition, e.g. details of setting alarm thresholds or avoiding false alarms alarms per se G08B
• CPC Class Codes: B60K 28/066 actuating a signalling device B60K28/063 takes precedence
• CPC Class Codes: G02B 2027/0138 comprising image capture systems, e.g. camera
• CPC Class Codes: G02B 2027/0187 slaved to motion of at least a part of the body of the user, e.g. head, eye
• CPC Class Codes: G02B 27/017 Head mounted
• CPC Class Codes: G06V 20/597 Recognising the driver's state or behaviour, e.g. attention or drowsiness
• CPC Class Codes: G08B 21/06 indicating a condition of sleep, e.g. anti-dozing alarms
• CPC Class Codes: G16H 30/40 for processing medical images, e.g. editing
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems
• CPC Class Codes: G16H 50/30 for calculating health indices; for individual health risk assessment

Abstract

Disclosed is a biological body state assessment device capable of accurately assessing an absentminded state of a driver. The biological body state assessment device first acquires face image data of a face image capturing camera, detects an eye open time and a face direction left/right angle of a driver from face image data, calculates variation in the eye open time of the driver and variation in the face direction left/right angle of the driver, and performs threshold processing on the variation in the eye open time and the variation in the face direction left/right angle to detect the absentminded state of the driver. The biological body state assessment device assesses the possibility of the occurrence of drowsiness of the driver in the future using a line fitting method on the basis of an absentminded detection flag and the variation in the eye open time, and when it is assessed that there is the possibility of the occurrence of drowsiness, estimates an expected drowsiness occurrence time of the driver.

Claims

1. A biological body state assessment device comprising:

face information acquisition means for acquiring face information of a driver;

eye open time variation calculation means for calculating variation in the eye open time of the driver on the basis of the face information of the driver;

face direction variation calculation means for calculating variation in the face direction of the driver on the basis of the face information of the driver; and

vigilance assessment means for assessing the vigilance of the driver on the basis of the variation in the eye open time of the driver and the variation in the face direction of the driver.

2. The biological body state assessment device according to claim 1,

wherein the vigilance assessment means assesses that, as the variation in the face direction of the driver becomes small, the vigilance of the driver is lowered.

3. The biological body state assessment device according to claim 1, further comprising:

drowsiness occurrence assessment means for assessing whether or not there is the possibility of the occurrence of drowsiness in the driver on the basis of the increase/decrease tendency of the variation in the eye open time of the driver after the absentminded state of the driver has been detected from the vigilance of the driver assessed by the vigilance assessment means.

4. The biological body state assessment device according to claim 3, further comprising:

drowsiness occurrence time prediction means for predicting the time at which drowsiness occurs in the driver on the basis of a slope of an approximate expression obtained by approximating the variation in the eye open time of the driver and a threshold value set in advance when the drowsiness occurrence assessment means assesses that there is the possibility of the occurrence of drowsiness in the driver.