Apparatus and method for automatic steering control in vehicle

• US 10,160,485 B2
• Filed: 07/07/2016
• Issued: 12/25/2018
• Est. Priority Date: 11/11/2015
• Status: Active Grant

• Current Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Original Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Inventors: You, Byung Yong, Heo, Myung Seon, Oh, Young Chul
• Primary Examiner(s): Ziaeianmehdizadeh, Navid
• Application Number:
  US15/204,849
• Publication Number:
  US 20170129535A1
• Time in Patent Office: 901 Days
• Field of Search: None
• CPC Class Codes: B62D 1/286 Systems for interrupting non-mechanical steering due to driver intervention
• CPC Class Codes: B62D 15/024 Other means for determination of steering angle without directly measuring it, e.g. deriving from wheel speeds on different sides of the car
• 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 6/002 computing target steering angles for front or rear wheels B62D7/159 takes precedence
• CPC Class Codes: G05D 1/0088 characterized by the autonomous decision making process, e.g. artificial intelligence, predefined behaviours using knowledge based models G06N5/00
• CPC Class Codes: G05D 1/0246 using a video camera in combination with image processing means

Abstract

A steering control method and device for autonomous vehicles is provided. The steering control method includes sensing traffic lanes on a road on which a vehicle is being driven and deriving a vanishing point positioned on lines extending from the traffic lanes. A sensitivity of a steering angle that corresponds to a vertical coordinate of the vanishing point in a matrix and an initial steering angle that corresponds to a horizontal coordinate are then determined. Further, a steering control value that corresponds to the initial steering angle and the sensitivity of the steering angle are determined.

Claims

1. A steering control method for autonomous vehicles, comprising:

sensing traffic lanes on a road on which a vehicle is being driven and deriving a vanishing point positioned on lines extending from the traffic lanes;

determining a sensitivity of a steering angle that corresponds to a vertical coordinate of the vanishing point in a matrix and determining an initial steering angle that corresponds to a horizontal coordinate;

determining a steering control value that corresponds to the initial steering angle and the sensitivity of the steering angle; and

controlling a steering operation of the vehicle based on the steering control value.

2. The steering control method according to claim 1, wherein, based on the vertical coordinate,

when the vanishing point is located in a center between an upper region and a lower region based on the vertical coordinate, the sensitivity of the steering angle is 1,

when the vanishing point is located in the upper region, the sensitivity of the steering angle is greater than 1, and

when the vanishing point is located in the lower region, the sensitivity of the steering angle is less than 1.

3. The steering control method according to claim 1, wherein, based on the horizontal coordinate,

when the vanishing point is located in a center between a left region and a right region based on the horizontal coordinate, the initial steering angle is 0 degrees, and

when the vanishing point is located in the left or the right region, the initial steering angle is a position proportional value between the center and a maximum steering angle.

4. The steering control method according to claim 3, wherein the maximum steering angle is a predetermined value that corresponds to a detection range of at least one imaging device mounted to the vehicle.

5. The steering control method according to claim 1, further comprising:

when the vanishing point is located in a center between an upper region and a lower region based on the vertical coordinate, determining an offset value of a steering control device mounted to the vehicle,

wherein the offset value is used to determine the steering control value.

6. The steering control method according to claim 1, wherein the initial steering angle is a value obtained by multiplying a maximum steering angle by a proportional value of the horizontal coordinate, and the proportional value ranges from −

1 to 1.

7. The steering control method according to claim 1, wherein the steering control value is determined by the following equation:

δ

=0.5[sgn(vp_y)+1]*(vp_y*steer_max)*weight_vpx−

0.5[sgn(vp_y)−

1]*(vp_y*steer_max)*weight_vpx+δ

_offset

wherein delta (δ

) is the steering control value, VPx and VPy are, respectively, a vertical coordinate value and a proportional value of the horizontal coordinate, each ranging from −

1 to 1,

sgn( ) is a function of outputting 1 when a variable is a positive value and outputting −

1 when a variable is a negative value, steer_max is a maximum steering angle, weight_VPx is the sensitivity of the steering angle, and delta (δ

)_offset is an offset value of a steering control device.

8. An apparatus for automatic steering control in a vehicle comprising a processing system that comprises at least one data processor and at least one non-transitory computer-readable memory storing a computer program, wherein the processing system is configured to cause the apparatus to:

sense traffic lanes on a road on which the vehicle is being driven and derive a vanishing point positioned on lines extending from the traffic lanes;

determine a sensitivity of a steering angle that corresponds to a vertical coordinate of the vanishing point in a matrix and determine an initial steering angle that corresponds to a horizontal coordinate;

determine a steering control value that corresponds to the initial steering angle and the sensitivity of the steering angle; and

control a steering operation of the vehicle based on the steering control value.

9. The apparatus according to claim 8, wherein the processing system is further configured to cause the apparatus to:

when the vanishing point is located in a center between an upper region and a lower region based on the vertical coordinate, determine an offset value of a steering control device mounted to the vehicle,

wherein the offset value is used to determine the steering control value.

10. The apparatus according to claim 8, wherein the initial steering angle is a value obtained by multiplying a maximum steering angle by a proportional value of the horizontal coordinate, and the proportional value ranges from −

1 to 1.

11. A steering control device for autonomous vehicles including a memory and a processor that is configured to:

sense traffic lanes on a road on which a vehicle is being driven;

derive a vanishing point positioned on lines extending from the traffic lanes;

store a vanishing point matrix for analyzing an environment of the road and a position of the vanishing point;

determine a sensitivity of a steering angle that corresponds to a vertical coordinate in the matrix, determine an initial steering angle that corresponds to a horizontal coordinate, and determine a steering control value that corresponds to the initial steering angle and the sensitivity of the steering angle; and

control a steering operation of the vehicle based on the steering control value.

12. The steering control device according to claim 11, wherein, based on the vertical coordinate,

when the vanishing point is located in a center between an upper region and a lower region based on the vertical coordinate, the sensitivity of the steering angle is 1,

when the vanishing point is located in the upper region, the sensitivity of the steering angle is greater than 1, and

when the vanishing point is located in the lower region, the sensitivity of the steering angle is less than 1.

13. The steering control device according to claim 11, wherein, based on the horizontal coordinate,

when the vanishing point is located in a center between a left region and a right region based on the horizontal coordinate, the initial steering angle is 0 degree, and

when the vanishing point is located in the left or the right region, the initial steering angle is a position proportional value between the center and a maximum steering angle.

14. The steering control device according to claim 13, wherein the maximum steering angle is a predetermined value that corresponds to a detection range of at least one camera mounted to the vehicle.

15. The steering control device according to claim 11, wherein, when the vanishing point is located in a center between an upper region and a lower region based on the vertical coordinate, the steering control device is configured to determine an offset value of the steering control device mounted to the vehicle, and determine the steering control value using the offset value.

16. The steering control device according to claim 11, wherein the initial steering angle is a value obtained by multiplying a maximum steering angle by a proportional value of the horizontal coordinate, and the proportional value ranges from −

1 to 1.