Vehicle motion control device

• US 9,540,003 B2
• Filed: 01/24/2014
• Issued: 01/10/2017
• Est. Priority Date: 03/29/2013
• Status: Active Grant

• Current Assignee: Hitachi Astemo Ltd. (Hitachi, Ltd.)
• Original Assignee: Hitachi Automotive Systems Limited (Hitachi, Ltd.)
• Inventors: Yamakado, Makoto, Sasaki, Mitsuhide, Ueyama, Mikio, Nagatsuka, Keiichiro
• Primary Examiner(s): Beaulieu, Yonel
• Application Number:
  US14/780,835
• Publication Number:
  US 20160059852A1
• Time in Patent Office: 1,082 Days
• US Class Current: 1/1
• CPC Class Codes: B60T 2201/022 Collision avoidance systems
• CPC Class Codes: B60T 2201/16 Curve braking control, e.g. turn control within ABS control algorithm
• CPC Class Codes: B60T 2230/04 Jerk, soft-stop; Anti-jerk, reduction of pitch or nose-dive when braking
• CPC Class Codes: B60T 7/12 for automatic initiation; for initiation not subject to will of driver or passenger limiting speed of vehicles other than rail vehicles B60K31/00
• CPC Class Codes: B60T 8/1755 Brake regulation specially adapted to control the stability of the vehicle, e.g. taking into account yaw rate or transverse acceleration in a curve road vehicle drive control systems for control of driving stability otherwise than by controlling a particular sub-unit B60W30/02
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/18 including control of braking systems
• CPC Class Codes: B60W 10/20 including control of steering systems
• CPC Class Codes: B60W 10/22 including control of suspension systems
• CPC Class Codes: B60W 2510/18 Braking system
• CPC Class Codes: B60W 2510/20 Steering systems
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2520/105 Longitudinal acceleration
• CPC Class Codes: B60W 2520/14 Yaw
• CPC Class Codes: B60W 2540/16 Ratio selector position
• CPC Class Codes: B60W 2554/00 Input parameters relating to objects
• CPC Class Codes: B60W 2556/50 of positioning data, e.g. GPS [Global Positioning System] data
• CPC Class Codes: B60W 2710/18 Braking system
• CPC Class Codes: B60W 2710/20 Steering systems
• CPC Class Codes: B60W 2720/40 : Torque distribution
• CPC Class Codes: B60W 2720/403 : between front and rear axle
• CPC Class Codes: B60W 2720/406 : between left and right wheel
• CPC Class Codes: B60W 30/02 : Control of vehicle driving stability
• CPC Class Codes: B60W 30/045 : Improving turning performance
• CPC Class Codes: B60W 30/09 : Taking automatic action to avoid collision, e.g. braking and steering
• CPC Class Codes: B60W 30/18145 : Cornering
• CPC Class Codes: B60W 40/107 : Longitudinal acceleration

Abstract

In order to reliably assist a driver in emergency detour steering without causing a jerking forward motion of the vehicle during normal operation, a vehicle motion control device includes: a risk potential estimator that estimates a risk potential of a vehicle based on input external information and vehicle information; a vehicle longitudinal motion controller that generates a longitudinal motion control command of the vehicle based on a vehicle lateral jerk and a predetermined gain; and a gain adjustor that adjusts the gain, in which the gain adjustor adjusts the gain based on the risk potential estimated by the risk potential estimator.

Claims

1. A vehicle motion control device comprising:

a risk potential estimator that estimates a risk potential of a vehicle based on input external information and vehicle information;

a vehicle longitudinal motion controller that generates a longitudinal motion control command of the vehicle based on a vehicle lateral jerk and a predetermined gain; and

a gain adjustor that adjusts the gain, wherein

the gain adjustor adjusts the gain based on the risk potential estimated by the risk potential estimator,

the vehicle longitudinal motion controller includes

an acceleration/deceleration controller that calculates a longitudinal acceleration command value of the vehicle based on the vehicle lateral jerk and a predetermined first gain, and outputs the longitudinal acceleration command value,

a yaw moment controller that calculates a yaw moment command value of the vehicle based on the vehicle lateral jerk and a predetermined second gain, and outputs the yaw moment command value,

the gain adjustor adjusts the first gain or the second gain based on the risk potential estimated by the risk potential estimator.

2. The vehicle motion control device according to claim 1,

wherein when the risk potential is detected by the risk potential estimator, the gain adjustor adjusts the gain to be large, compared with a case where the risk potential is not detected.

3. The vehicle motion control device according to claim 1,

wherein when the risk potential estimated by the risk potential estimator is higher than a predetermined value, the gain adjustor adjusts the first gain or the second gain to be large, compared with a case where the value is lower than the predetermined value.

4. The vehicle motion control device according to claim 1,

wherein the gain adjustor adjusts the first gain and the second gain based on the risk potential estimated by the risk potential estimator.

5. The vehicle motion control device according to claim 2,

wherein when the risk potential is not detected, the gain adjustor adjusts the gain to be zero.

6. The vehicle motion control device according to claim 1,

wherein the external information is host vehicle front external information obtained from a camera or a radar, and

the vehicle information is at least one piece of information among a vehicle velocity, a steering angle, an acceleration, a yaw rate, a pedal operation velocity, and a braking operation velocity.

7. The vehicle motion control device according to claim 1,

wherein the risk potential estimator estimates quantitative evaluation of the risk potential of the vehicle.

8. The vehicle motion control device according to claim 1,

wherein the quantitative evaluation of the risk potential of the vehicle is performed by quantification based on a time-to-collision or a steering angular velocity.

9. The vehicle motion control device according to claim 1,

wherein the gain adjustor outputs the gain corresponding to the estimated risk potential using a map in which a value of the gain depending on a risk potential which is stored in advance is written.

10. The vehicle motion control device according to claim 1,

wherein the vehicle longitudinal motion controller generates the longitudinal motion control command of the vehicle so that the vehicle is decelerated when an absolute value of a lateral acceleration of the vehicle increases, and is accelerated when the absolute value of the lateral acceleration of the vehicle decreases.

11. The vehicle motion control device according to claim 1,

wherein the vehicle longitudinal motion controller generates the longitudinal motion control command of the vehicle so that the vehicle is decelerated when an absolute value of a steering angle of the vehicle increases, and is accelerated when the absolute value of the steering angle of the vehicle decreases.

12. The vehicle motion control device according to claim 1,

wherein the longitudinal acceleration command value Gxc is as follows:

13. The vehicle motion control device according to claim 1,

wherein the yaw moment command value is generated to promote turning of the vehicle when an absolute value of a lateral acceleration of the vehicle increases, and to return the turning of the vehicle when the absolute value of the lateral acceleration of the vehicle decreases.

14. The vehicle motion control device according to claim 1,

wherein the yaw moment command value is generated to promote turning of the vehicle when an absolute value of a steering angle of the vehicle increases, and to return the turning of the vehicle when the absolute value of the steering angle of the vehicle decreases.

15. The vehicle motion control device according to claim 1,

wherein the yaw moment command value Mz+ is as follows:

16. The vehicle motion control device according to claim 1,

wherein the yaw moment command value Mz+/V is as follows:

17. The vehicle motion control device according to claim 1,

wherein the longitudinal motion control command includes an acceleration command and a deceleration command,

the acceleration command becomes zero when a braking operation command input from a driver exceeds a predetermined threshold value, and

the deceleration command becomes zero when an accelerator operation command input from the driver exceeds a predetermined threshold value.

18. The vehicle motion control device according to claim 1,

wherein the risk potential estimator estimates the risk potential of the vehicle based on information about a distance to an obstacle obtained from a stereo camera.