System and method for detecting driver drowsiness including detection of steering rotation and reversal
First Claim
Patent Images
1. A system for detecting driver drowsiness in an automotive vehicle, comprising:
- (a) a first sensor means for detecting rotation of a steering wheel of the vehicle and outputting a pulse whenever the steering wheel is rotated through a predetermined angle, said pulse indicating the rotational direction of the steering wheel;
(b) a second sensor means for detecting the speed of the vehicle and outputting a signal according to the speed of the vehicle;
(c) a first determination means for determining whether the number of pulses produced by said first sensor means within a time interval of a first duration exceeds a first reference value when the vehicle speed detected by said second sensor means exceeds a first, low, predetermined value of speed;
(d) a second determination means for determining whether the number of steering reversals within a time interval of said first duration, each steering reversal being detected as a change in the rotational direction between two consecutive pulses, is below a second reference value when the vehicle speed detected by said second sensor means exceeds said first, low, predetermined value of speed; and
(e) an alarm means for producing an alarm when said first determination means determines that the number of pulses produced within a time interval of said first duration exceeds said first reference value and when said second determination means determines that the number of steering reversals within a time interval of said first duration is below said second reference value.
1 Assignment
0 Petitions
Accused Products
Abstract
A system and method for detecting driver drowsiness in an automotive vehicle employs means for detecting changes in steering direction of a steering wheel on the basis of steering pulses, each steering pulse being produced whenever the steering wheel is rotated through a predetermined angle, and determines that the vehicle driver is drowsy when the number of steering pulses within a fixed interval of time exceeds a first reference value and the number of steering reversals within the fixed interval of time is below a second preset reference value.
56 Citations
14 Claims
-
1. A system for detecting driver drowsiness in an automotive vehicle, comprising:
-
(a) a first sensor means for detecting rotation of a steering wheel of the vehicle and outputting a pulse whenever the steering wheel is rotated through a predetermined angle, said pulse indicating the rotational direction of the steering wheel; (b) a second sensor means for detecting the speed of the vehicle and outputting a signal according to the speed of the vehicle; (c) a first determination means for determining whether the number of pulses produced by said first sensor means within a time interval of a first duration exceeds a first reference value when the vehicle speed detected by said second sensor means exceeds a first, low, predetermined value of speed; (d) a second determination means for determining whether the number of steering reversals within a time interval of said first duration, each steering reversal being detected as a change in the rotational direction between two consecutive pulses, is below a second reference value when the vehicle speed detected by said second sensor means exceeds said first, low, predetermined value of speed; and (e) an alarm means for producing an alarm when said first determination means determines that the number of pulses produced within a time interval of said first duration exceeds said first reference value and when said second determination means determines that the number of steering reversals within a time interval of said first duration is below said second reference value. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. A method for detecting driver drowsiness automotive vehicle, comprising the steps of:
-
(a) determining whether the vehicle speed exceeds a lower predetermined value of speed; (b) determining whether a number of pulses within a time interval of a first duration exceeds a first reference value, each of the pulses being produced whenever a steering wheel of the vehicle is rotated through a predetermined angle while the vehicle speed exceeds said lower predetermined value of speed determined in said step (a), each pulse indicating the direction of rotation of the steering wheel; (c) while the vehicle speed exceeds said lower predetermined value of speed, determining whether a number of steering reversals within a time interval of said first duration is below a second reference value, each steering reversal being detected when one of said pulses and the subsequent pulse are derived from different rotational directions of the steering wheel; and (d) producing an alarm when the number of pulses within a time interval of said first duration exceeds said first reference value determined in said step (b) and the number of steering reversals within said time interval of said first duration is below said second reference value determined in said step (c). - View Dependent Claims (10, 11, 12, 13)
-
-
14. A method for detecting driver drowsiness in an automotive vehicle, comprising the steps of:
-
(a) determining whether a number of pulses within a first duration interval of time exceeds a first reference value, each of the pulses being produced whenever a steering wheel of the vehicle is rotated through a predetermined angle, each pulse indicating the direction of rotation of the steering wheel; (b) determining whether the number of steering reversals within a first duration interval of time is below a second reference value, each steering reversal being detected when one of said pulses and the subsequent pulse thereto are derived from different rotational directions of the steering wheel; and (c) producing an alarm when the number of pulses within a first duration interval of time exceeds said first reference value determined in said step (a) and the number of steering reversals within said first duration interval of time is below said second reference value determined in said step (b).
-
Specification