STEERING RETENTION STATE JUDGING DEVICE, DRIVER WAKEFULNESS PREDICTING DEVICE, AND CORRECT COURSE KEEPING DEVICE

• US 20080262676A1
• Filed: 03/10/2008
• Published: 10/23/2008
• Est. Priority Date: 03/12/2007
• Status: Active Grant

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Urai, Yoshihiro, Kawakami, Kenta
• Granted Patent: US 8,190,329 B2
• Time in Patent Office: Days
• US Class Current: 701/41
• CPC Class Codes: B60W 2040/0827 due to sleepiness
• CPC Class Codes: B60W 40/09 Driving style or behaviour
• CPC Class Codes: B62D 15/025 Active steering aids, e.g. helping the driver by actively influencing the steering system after environment evaluation B62D1/28 takes precedence
• CPC Class Codes: B62D 15/029 Steering assistants using warnings or proposing actions to the driver without influencing the steering system
• CPC Class Codes: B62D 6/007 adjustable by the driver, e.g. sport mode

Abstract

This steering wheel retention state judging device includes: a torque application unit that applies a torque on a steering wheel of a vehicle, the steering wheel operated by a driver; an angle sensor that detects a steering angle of the steering wheel; and a steering wheel retention state judging unit that judges a retention state of the steering wheel by the driver based on the steering angle of the steering wheel when the torque is applied by the torque application unit.

Claims

1. A steering wheel retention state judging device comprising:

a torque application unit that applies a torque on a steering wheel of a vehicle;

an angle sensor that detects a steering angle of the steering wheel; and

a steering wheel retention state judging unit that judges a retention state of the steering wheel by the driver, based on the steering angle of the steering wheel when the torque is applied by the torque application unit.

2. The steering wheel retention state judging device according to claim 1, wherein

the steering wheel retention state judging unit judges that the driver does not retain the steering wheel normally when a change in steering angle or a change in steering angle per unit time, in response to the torque applied by the torque application unit, becomes equal to or greater than a predetermined value.

3. A driver wakefulness estimating device comprising:

the steering wheel retention state judging device according to claim 1;

a memory device that stores a plurality of the changes in steering angle or the changes in steering angle per unit time, in response to the torque applied by the torque application unit; and

a driver wakefulness estimating unit that estimates the driver'"'"'s wakefulness as being decreased when the change in steering angle or the change in steering angle per unit time, in response to the torque applied by the torque application unit, increases over a period of time.

4. A driver wakefulness estimating device comprising:

the steering wheel retention state judging device according to claim 1; and

a driver wakefulness estimating unit that estimates the driver'"'"'s wakefulness as being decreased when the change in steering angle or the change in steering angle per unit time, in response to the torque applied by the torque application unit, becomes on or above a threshold value for a number of times that is greater than a predetermined number of times.

10. The driver wakefulness estimating device according to any one of claims 3, 4, 8, and 9, that operates the steering wheel retention state judging device to judge the steering wheel retention state when a steering frequency of the driver is on or below a predetermined value.

11. The driver wakefulness estimating device according to any one of claims 3, 4, 8, and 9, wherein, when the torque is applied by the torque application unit, a connection between the steering wheel and a vehicle wheel is disconnected, so that the steering wheel rotates independently of the vehicle wheel.

12. The driver wakefulness estimating device according to any one of claims 3, 4, 8, and 9, further comprising an alarm device which is activated when the driver wakefulness is estimated to be decreased.

13. A correct course keeping device comprising:

the steering wheel retention state judging device according to any one of claims 1, 5, and 6; and

an alarm device or a steering control device, wherein;

the alarm device or the steering control device is activated when a probability of the vehicle deviating from a correct course becomes equal to or higher than a predetermined probability; and

conditions under which the alarm device or the steering control device is activated are broadened when the driver is judged as not retaining the steering wheel normally.

14. A correct course keeping device comprising:

the driver wakefulness estimating device according to any one of claims 3, 4, 8, and 9; and

an alarm device or a steering control device, wherein

the alarm device or the steering control device is activated when a probability of the vehicle deviating from a correct course becomes higher than a predetermined probability, and

conditions under which the alarm device or the steering control device is activated are broadened when the wakefulness estimating unit estimates that the driver'"'"'s wakefulness is decreased.

15. The steering wheel retention state judging device according to claim 1, wherein

the torque application unit applies a torque so as to cancel out the steering angle by the driver, when the amount of the steering angle is equal to or below a predetermined value.

5. A steering wheel retention state judging device comprising:

a torque application unit that applies a torque on a steering wheel of a vehicle;

a torque sensor that detects a steering torque of the steering wheel operated by a driver; and

a steering wheel retention state judging unit that judges a retention state of the steering wheel by the driver based on the steering torque detected by the torque sensor when the torque is applied by the torque application unit.

16. The steering wheel retention state judging device according to claim 5 or 6, wherein

the torque application unit applies a torque equivalent in size to the steering torque by the driver in a direction so as to cancel out the steering torque, when the magnitude of the steering torque is equal to or below a predetermined value.

6. A steering wheel retention state judging device comprising:

a torque application unit that applies a torque on a steering wheel such that a steering angle of a vehicle becomes equal to a target steering angle;

a torque sensor that detects a steering torque of the steering wheel operated by a driver; and

a steering wheel retention state judging unit that judges a retention state of the steering wheel by the driver based on the steering torque detected by the torque sensor when the torque is applied by the torque application unit.

7. The steering wheel retention state judging device according to claim 6, wherein

the steering wheel retention state judging unit judges that the driver does not retain the steering wheel normally when a change in the steering torque or a change in the steering torque per unit time, in response to the torque applied by the torque application unit, becomes equal to or smaller than a predetermined value.

8. A driver wakefulness estimating device comprising:

the steering wheel retention state judging device according to claim 6;

a memory device that stores a plurality of changes in the steering torque or changes in the steering torque per unit time, in response to the torque applied by the torque application unit; and

a driver wakefulness estimating unit that estimates the driver'"'"'s wakefulness as being decreased when a change in the steering torque or a change in the steering torque per unit time, in response to the torque applied by the torque application unit, decreases over a period of time.

9. A driver wakefulness estimating device comprising:

the steering wheel retention state judging device according to claim 6; and

a wakefulness estimating unit that estimates the driver'"'"'s wakefulness as being decreased when a change in the steering torque or a change in the steering torque per unit time, in response to the torque applied by the torque application unit, becomes equal to or smaller than a predetermined value for a number of times that is greater than a predetermined number of times.