Travel trajectory control device for a vehicle

• US 9,527,525 B2
• Filed: 12/26/2012
• Issued: 12/27/2016
• Est. Priority Date: 12/26/2011
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Inoue, Go
• Primary Examiner(s): SMITH, JELANI A
• Application Number:
  US14/369,010
• Publication Number:
  US 20150259006A1
• Time in Patent Office: 1,462 Days
• Field of Search: 701/41
• US Class Current: 1/1
• 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
• CPC Class Codes: B62D 6/007 adjustable by the driver, e.g. sport mode

Abstract

Provided is a travel trajectory control device for a vehicle which executes a vehicle travel trajectory control by calculating a target steering angle corresponding to a target steered angle of the front wheels for making a vehicle travel to track a target trajectory, and controlling the steered angle of the front wheels on the basis of the target steered angle with a steered angle varying device and a power steering device. The driving ability of a driver and/or a trajectory change intent thereof are determined. On the basis of a driving ability index value and/or an index value which denotes the intensity of the trajectory change intent of the driver, the tracking of the vehicle to the target trajectory is variably set by variably setting the gain in the travel trajectory control.

Claims

1. A travel trajectory control device for a vehicle which executes a vehicle travel trajectory control comprising:

circuitry configured to;

calculate a target steered angle of steered wheels for making a vehicle travel to track a target trajectory;

control a steered angle of the steered wheels on the basis of the target steered angle with a steered angle varying device independently of a presence of a steering operation of a driver;

determine at least one of a driving ability of the driver and a trajectory change intent of the driver during execution of the vehicle travel trajectory control; and

variably set tracking of the vehicle to the target trajectory in accordance with a result of the determination by varying a gain of the vehicle travel trajectory control on a basis of the result of the determination,

wherein the circuitry is further configured to;

determine the driving ability of the driver on the basis of a change rate of a difference between an actual travel parameter reflecting the steering operation of the driver and a target travel parameter for making the vehicle travel to track the target trajectory;

determine the driving ability of the driver on a basis of a weighted sum of a first driving ability determination value based on a change rate of a difference of lateral positions of the vehicle and a second driving ability determination value based on a change rate of a difference of yaw angles of the vehicle; and

when a curvature radius of a lane is large, increase the weight of the first driving ability determination value, as compared to where the curvature radius of the lane is small.

2. The travel trajectory control device for a vehicle according to claim 1, wherein the circuitry is configured to, when the driver has a high driving ability, set the tracking of the vehicle to the target trajectory lower by reducing the gain of the vehicle travel trajectory control, as compared to where the driver has a low driving ability.

3. The travel trajectory control device for a vehicle according to claim 1, wherein the circuitry is configured to, when the driver has an intensive trajectory change intent, set the tracking of the vehicle to the target trajectory lower by reducing the gain of the vehicle travel trajectory control, as compared to where the driver has a weak trajectory change intent.

4. The travel trajectory control device for a vehicle according to claim 1, wherein the circuitry is configured to make the determination as to whether or not the driver has the trajectory change intent on a basis of a duration time for which a magnitude of a difference between an actual travel parameter reflecting the steering operation of the driver and a target travel parameter for making the vehicle travel to track the target trajectory is not less than a reference value.

5. The travel trajectory control device for a vehicle according to claim 4, wherein the circuitry is configured to determine an intensity of the trajectory change intent of the driver on a basis of a product of the magnitude of the difference and the duration time in a situation where it is determined that the driver has the trajectory change intent.

6. The travel trajectory control device for a vehicle according to claim 1, wherein the circuitry is configured to:

estimate at least one of travel trajectory parameters which are lateral position of the vehicle relative to a lane, curvature radius of the lane, and a yaw angle of the vehicle relative to the lane on a basis of information of the lane; and

calculate the target steered angle of the steered wheels on the basis of the at least one of the travel trajectory parameters.

7. The travel trajectory control device for a vehicle according to claim 1, wherein the circuitry is configured to use the target travel parameter from which an influence of the travel trajectory control is eliminated.

8. The travel trajectory control device for a vehicle according to claim 1, wherein the circuitry is configured to, when a vehicle speed is high, decrease a change rate in changing the tracking of the vehicle, as compared to where a vehicle speed is low.

9. A travel trajectory control device for a vehicle which executes a vehicle travel trajectory control comprising:

circuitry configured to;

calculate a target steered angle of steered wheels for making a vehicle travel to track a target trajectory;

control a steered angle of the steered wheels on the basis of the target steered angle with a steered angle varying device independently of a presence of a steering operation of a driver;

determine at least one of a driving ability of the driver and a trajectory change intent of the driver during execution of the vehicle travel trajectory control, and

variably set tracking of the vehicle to the target trajectory in accordance with a result of the determination by varying a gain of the vehicle travel trajectory control on a basis of the result of the determination, wherein

the circuitry is further configured to;

determine the driving ability of the driver on the basis of a change rate of a difference between an actual travel parameter reflecting the steering operation of the driver and a target travel parameter for making the vehicle travel to track the target trajectory;

have a control mode in which the travel trajectory control is executed and a non-control mode in which the travel trajectory control is not executed; and

calculate the target steered angle of the steered wheels in the non-control mode,

the difference includes a difference between the target steered angle of the steered wheels and an actual steered angle of the steered wheels, and

the circuitry is configured to, in the non-control mode;

determine the driving ability of the driver on a basis of a weighted sum of a third driving ability determination value based on a difference of steered angles and a fourth driving ability determination value based on a phase difference between the target steered angle of the steered wheels and the actual steered angle of the steered wheels; and

when a curvature radius of a lane is large, increase the weight of the third driving ability determination value, as compared to where the curvature radius of the lane is small.

10. The travel trajectory control device for a vehicle according to claim 9, wherein

the steered angle varying device is configured to vary a responsiveness in varying the steered angle of the steered wheels in response to the steering operation of the driver, and

in the non-control mode, the circuitry is configured to variably set the responsiveness of the steered angle varying device in accordance the driving ability of the driver.

11. The travel trajectory control device for a vehicle according to claim 10, wherein the circuitry is configured to:

store the responsiveness of the steered angle varying device which corresponds to the tracking of the vehicle when the mode is changed from the control mode to the non-control mode; and

when the vehicle continues to travel in the non-control mode, control the responsiveness of the steered angle varying device on a basis of the stored responsiveness.

12. The travel trajectory control device for a vehicle according to claim 10, wherein the circuitry is configured to:

store the responsiveness of the steered angle varying device when the vehicle finishes traveling in the non-control mode; and

control the responsiveness of the steered angle varying device on a basis of the stored responsiveness when the vehicle starts traveling in the non-control mode.