Driving support apparatus and driving support method

• US 9,505,401 B2
• Filed: 09/28/2011
• Issued: 11/29/2016
• Est. Priority Date: 10/01/2010
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Akiyama, Tomonori, Igarashi, Shinji, Yoshihama, Yuki
• Primary Examiner(s): CASS, JEAN PAUL
• Application Number:
  US13/877,114
• Publication Number:
  US 20130226409A1
• Time in Patent Office: 1,889 Days
• Field of Search: 701/41
• US Class Current: 1/1
• CPC Class Codes: B60T 2201/083 using active brake actuation
• CPC Class Codes: B60T 2201/085 using several actuators; Coordination of the lane keeping system with other control systems
• CPC Class Codes: B60T 2201/087 using active steering actuation
• CPC Class Codes: B60T 8/17557 specially adapted for lane departure prevention road vehicle drive control systems for lane keeping otherwise than by controlling a particular sub-unit B60W30/12
• CPC Class Codes: B60W 10/184 with wheel brakes
• CPC Class Codes: B60W 10/20 including control of steering systems
• CPC Class Codes: B60W 2520/14 Yaw
• CPC Class Codes: B60W 2720/14 Yaw
• CPC Class Codes: B60W 30/02 Control of vehicle driving stability
• CPC Class Codes: B60W 30/12 Lane keeping
• 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 6/003 in order to control vehicle yaw movement, i.e. around a vertical axis B62D6/007 takes precedence

Abstract

Disclosed is a driving support apparatus for setting a traveling lane in which a vehicle can travel on the basis of a road marking to indicate a lane boundary or a traveling-prohibited region and performing support by combining steering of the vehicle and deceleration of the vehicle so that the vehicle is allowed to travel in the traveling lane if the vehicle is to be departed from the traveling lane, wherein the steering of the vehicle and the deceleration of the vehicle, which are to be performed when the support is performed so that the vehicle is allowed to travel in the traveling lane, are individually controlled depending on a difference ΔY between a target yaw rate Ytrg and an actual yaw rate Yrea if the actual yaw rate Yrea is smaller than the target yaw rate Ytrg in order not to allow the vehicle to exceed the traveling lane.

Claims

1. A driving support apparatus for setting a traveling lane in which a vehicle can travel on the basis of a road marking to indicate a lane boundary or a traveling-prohibited region and performing support by combining steering wheel control of the vehicle and deceleration of the vehicle so that the vehicle is allowed to travel in the traveling lane when the vehicle is to be departed from the traveling lane, the driving support apparatus comprising an electronic control unit (ECU) configured to perform

so that the vehicle is allowed to travel in the traveling lane based on an output from at least any one of a yaw rate sensor, a lateral acceleration sensor, and a wheel velocity sensor,

the ECU is further configured to:

calculate a required value indicating lateral movement required to avoid departure of the vehicle from the traveling lane;

when the calculated required value is smaller than a first threshold value, perform only the steering wheel control of the vehicle as the support for the driving in order to avoid the departure from the traveling lane without performing the deceleration of the vehicle;

when the obtained required value is not less than the first threshold value and smaller than a second threshold value, the second threshold value being set as a lower limit of the required value where simultaneous control of a speed and a steering wheel of the vehicle causes the vehicle to be unstable, perform the steering wheel control of the vehicle as the support for the driving in order to avoid the departure from the traveling lane and the deceleration of the vehicle simultaneously; and

when the obtained required value is not less than the second threshold value, perform the steering wheel control of the vehicle as the support for the driving in order to avoid the departure from the traveling lane after decelerating the vehicle.

2. A driving support apparatus for setting a traveling lane in which a vehicle can travel on the basis of a road marking to indicate a lane boundary or a traveling prohibited region and performing support by combining steering wheel control of the vehicle and deceleration of the vehicle so that the vehicle is allowed to travel in the traveling lane when the vehicle is to be departed from the traveling lane, the driving support apparatus comprising an electronic control unit (ECU) configured to perform the support

so that the vehicle is allowed to travel in the traveling lane based on an output from at least any one of a yaw rate sensor, a lateral acceleration sensor, and a wheel velocity sensor,

the ECU is further configured to:

obtain an angle between the vehicle'"'"'s traveling direction and the boundary of the traveling lane;

when the obtained angle is smaller than a first threshold value, perform only the steering wheel control of the vehicle as the support for the driving in order to avoid the departure from the traveling lane without performing the deceleration of the vehicle;

when the obtained angle is not less than the first threshold value and smaller than a second threshold value, the second threshold value being set as a lower limit of the angle between the vehicle'"'"'s traveling direction and the boundary of the traveling lane where simultaneous control of a speed and a steering wheel of the vehicle causes the vehicle to be unstable, perform the steering wheel control of the vehicle as the support for the driving in order to avoid the departure from the traveling lane and the deceleration of the vehicle simultaneously; and

when the obtained angle is not less than the second threshold value, perform the steering wheel control of the vehicle as the support for driving in order to avoid the departure from the traveling lane after decelerating the vehicle.

3. A driving support method comprising:

a step of setting a traveling lane in which a vehicle can travel on the basis of a road marking to indicate a lane boundary or a traveling-prohibited region; and

a step of performing support by combining steering of the vehicle and deceleration of the vehicle so that the vehicle is allowed to travel in the traveling lane when the vehicle is to be departed from the traveling lane, wherein

when the support is performed so that the vehicle is allowed to travel in the traveling lane based on an output from at least any one of a yaw rate sensor, a lateral acceleration sensor, and a wheel velocity sensor,

when an actual value is smaller than a target value of a parameter which indicates lateral movement in order to avoid departure of the vehicle from the traveling lane and the difference between the target value and the actual value is smaller than a first threshold value, only the steering wheel control of the vehicle as the support for the driving in order to avoid the departure from the traveling lane is performed without performing the deceleration of the vehicle;

when the difference between the target value and the actual value is not less than the first threshold value and smaller than a second threshold value, the second threshold value being set as a lower limit of the difference between the target value and the actual value where simultaneous control of a speed and a steering wheel of the vehicle causes the vehicle to be unstable, the steering wheel control of the vehicle as the support for the driving in order to avoid the departure from the traveling lane and the deceleration of the vehicle are performed simultaneously; and

when the difference between the target value and the actual value is not less than the second threshold value, the steering wheel control of the vehicle as the support for the driving in order to avoid the departure from the traveling lane is performed after previously decelerating the vehicle.

4. A driving support method comprising:

a step of setting a traveling lane in which a vehicle can travel on the basis of a road marking to indicate a lane boundary or a traveling prohibited region; and

a step of performing support by combining steering wheel control of the vehicle and deceleration of the vehicle so that the vehicle is allowed to travel in the traveling lane when the vehicle is to be departed from the traveling lane, wherein;

when the support is performed so that the vehicle is allowed to travel in the traveling lane based on an output from at least any one of a yaw rate sensor, a lateral acceleration sensor, and a wheel velocity sensor,

when an angle between the vehicle'"'"'s traveling direction and the boundary of the traveling lane is smaller than a first threshold value, only the steering wheel control of the vehicle as the support for the driving in order to avoid the departure from the traveling lane is performed without performing the deceleration of the vehicle;

when an angle between the vehicle'"'"'s traveling direction and the boundary of the traveling lane is not less than the first threshold value and smaller than a second threshold value, the second threshold value being set as a lower limit of the angle between the vehicle'"'"'s traveling direction and the boundary of the traveling lane where simultaneous control of a speed and a steering wheel of the vehicle causes the vehicle to be unstable, the steering wheel control of the vehicle as the support for the driving in order to avoid the departure from the traveling lane and the deceleration of the vehicle are performed simultaneously; and

when an angle between the vehicle'"'"'s traveling direction and the boundary of the traveling lane is not less than the second threshold value, perform the steering wheel control of the vehicle as the support for the driving in order to avoid the departure from the traveling lane after decelerating the vehicle.