Method and system for detection of driver drowsiness by an abrupt steering change following no steering movement
First Claim
Patent Images
1. A method for detecting driver drowsiness in an automotive vehicle, comprising the steps of:
- (a) monitoring a position of a vehicular steering wheel and signalling direction and magnitude of change in the position of the steering wheel;
(b) measuring a first duration of a period of time during which no noticeable changes in the position of the steering wheel are monitored;
(c) determining whether said first duration of period of time measured in said step (b) is longer than any one of a plurality of given periods of time;
(d) if said first duration is longer than one of said time periods, selecting one of a plurality of sets of predetermined conditions in accordance with said first duration;
(e) determining whether noticeable changes in the position of the steering wheel immediately following said first duration satisfy said selected one of said plurality of sets of predetermined conditions; and
(f) activating an alarm device indicating driver drowsiness when said first duration is determined to be longer than one of said plurality of given periods of time in said step (c) and said noticeable changes in the position of the steering wheel determined in said step (e) satisfy said selected one of said sets of predetermined conditions selected in said step (d).
1 Assignment
0 Petitions
Accused Products
Abstract
A drowsiness alarm system for a vehicle detects and signals that the vehicle driver is drowsy on the basis of the duration during which no steering adjustments are made and the magnitude and speed of abrupt steering adjustments immediately following the non-steering period. Parameters compared to the magnitude and speed of the abrupt steering adjustments in order to recognize steering behavior reflecting drowsiness are adjusted in accordance with the duration of the non-steering period.
-
Citations
23 Claims
-
1. A method for detecting driver drowsiness in an automotive vehicle, comprising the steps of:
-
(a) monitoring a position of a vehicular steering wheel and signalling direction and magnitude of change in the position of the steering wheel; (b) measuring a first duration of a period of time during which no noticeable changes in the position of the steering wheel are monitored; (c) determining whether said first duration of period of time measured in said step (b) is longer than any one of a plurality of given periods of time; (d) if said first duration is longer than one of said time periods, selecting one of a plurality of sets of predetermined conditions in accordance with said first duration; (e) determining whether noticeable changes in the position of the steering wheel immediately following said first duration satisfy said selected one of said plurality of sets of predetermined conditions; and (f) activating an alarm device indicating driver drowsiness when said first duration is determined to be longer than one of said plurality of given periods of time in said step (c) and said noticeable changes in the position of the steering wheel determined in said step (e) satisfy said selected one of said sets of predetermined conditions selected in said step (d). - View Dependent Claims (2, 3)
-
-
4. A method of detecting driver drowsiness in an automotive vehicle, comprising the steps of:
-
(a) monitoring a position of a vehicular steering wheel and signalling direction, magnitude, and rate of change in the position of the steering wheel; (b) measuring a first duration of periods of time during which no noticeable changes in the position of the steering wheel are monitored; (c) measuring a second duration of periods of time during which the position of the steering wheel is changed consistently in one direction to an amount which exceeds a first reference value at a rate greater than a second reference value; (d) activating an alarm device indicating driver drowsiness when a period is measured in which no noticeable steering changes in the position of the steering wheel are monitored and said change in said steering wheel position in said second duration of the period immediately following said no-steering-change period exceeds said first reference value; and (e) adjusting at least one of said first and second reference values in accordance with said measured first duration of said no-steering-change period. - View Dependent Claims (5, 6, 7, 8, 13)
-
-
9. A system for detecting driver drowsiness in an automotive vehicle, comprising:
-
(a) a first sensor means for detecting direction and magnitude of rotational movement of a vehicular steering wheel and outputting a steering pulse signal whenever said steering wheel is rotated through a predetermined angle, said steering pulse signal indicating the rotational direction of said steering wheel; (b) a first determination means responsive to said output signals from said first sensor means for determining whether an episode of non-steering continues for at least a set minimum interval of time based on an interval of time between two consecutive steering pulse signals derived from said first sensor means; (c) a second determination means for determining whether a first abrupt unidirectional steering adjustment exceeding a first predetermined angle of steering change and a first predetermined angular speed of steering change occurs, after determination by said first determination means that a non-steering episode has continued for at least said minimum interval of time, based on intervals of time between consecutive steering pulse signals indicating rotation of steering wheel in a single direction and a number of such steering pulse signals within a first predetermined interval of time, at least one value of said first predetermined angle of steering change and angular speed of steering change being adjusted according to the duration of said non-steering episode determined by said first determination means; (d) a third determination means for determining whether a second unidirectional abrupt steering adjustment occurs, exceeding a second predetermined angle of steering change and a second predetermined angular speed of steering change in the direction of rotation opposite said first unidirectional abrupt steering adjustment, after said first unidirectional abrupt steering adjustment determined by said first determination means, on the basis of the intervals of time between consecutive steering pulse signals indicating the same direction rotation of the steering wheel and the number of such steering pulses within a second predetermined interval of time; and (e) an alarm means responsive to the result of said third determination means for producing an alarm when said third determination means determines that said second unidirectional abrupt steering adjustment has occurred. - View Dependent Claims (10, 11, 12, 14, 16)
-
-
15. A method for detecting driver drowsiness in an automotive vehicle, comprising the steps of:
-
(a) monitoring a position of a vehicular steering wheel and signalling direction and magnitude of change in the position of the steering wheel; (b) measuring a first duration of a period of time during which no noticeable changes in the position of the steering wheel are monitored; (c) determining whether said first duration of period of time measured in said step (b) is longer than any one of a plurality of given periods of time; (d) if said first duration is longer than one of said time periods, determining whether noticeable changes in the position of the steering wheel immediately following said first duration satisfy a predetermined condition; (e) varying said predetermined condition for the determination of said step (d) in accordance with said first duration determined in said step (c); and (f) activating an alarm device indicating driver drowsiness when said first duration is determined to be longer than one of said plurality of given periods of time in said step (c) and said noticeable changes in the position of the steering wheel determined in said step (d) satisfy said predetermined condition in said step (e).
-
-
17. A method for detecting driver drowsiness in an automotive vehicle comprising the steps of:
-
(a) detecting a period of substantially no steering operations; (b) detecting substantially immediately after said period of no steering operations a first steering operation in a first direction; (c) determining whether said first steering operation is an abrupt operation by comparing detected characteristics thereof with first predetermined criteria; and (d) activating an alarm means only if said first steering operation is an abrupt steering operation immediately following said period of no steering operations and is immediately followed by a second abrupt steering operation in an opposite direction. - View Dependent Claims (18, 19, 20, 21, 22)
-
-
23. A method for detecting driver drowsiness in an automotive vehicle, comprising the steps of:
-
(a) monitoring a position of a vehicular steering wheel and storing direction and magnitude of change in the position of the steering wheel; (b) measuring a first duration of a period of time during which no noticeable changes in the position of the steering wheel are monitored; (c) determining whether said first duration of period of time measured in said step (b) is longer than any one of a plurality of given periods of time; (d) if said first duration is longer than one of said time periods, selecting one of a plurality of sets of predetermined conditions in accordance with said first duration; (e) determining whether noticeable changes in the position of the steering wheel immediately following said first duration satisfy said selected one of said plurality of sets of predetermined conditions; (f) activating an alarm device indicating driver drowsiness when said first duration is determined to be longer than one of said plurality of given periods of time in said step (c) and said noticeable changes in the position of the steering wheel determined in said step (e) satisfy said selected one of said sets of predetermined conditions selected in said step (d).
-
Specification