PATH PLANNING METHOD FOR VEHICLE GUIDANCE

• US 20150331423A1
• Filed: 11/12/2013
• Published: 11/19/2015
• Est. Priority Date: 12/24/2012
• Status: Active Grant

• Current Assignee: AGCO International GmbH (AGCO International Holdings BV)
• Original Assignee: AGCO International GmbH (AGCO International Holdings BV)
• Inventors: VOLGER, Theo, GRANDL, Ludwig, KIENINGER, Bastain
• Granted Patent: US 9,861,024 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A01B 69/008 automatic
• CPC Class Codes: A01B 71/02 Setting or adjusting mechanisms
• CPC Class Codes: G05D 1/0219 ensuring the processing of the whole working surface

Abstract

A method for defining a contoured path for an automatic guidance system comprises defining a plurality of reference path segments; for each segment, determining one or more intersection points respectively with other segments; and subsequently defining a contoured path as a sequence of intersecting segments. An automatic guidance system based on the method is also provided.

Claims

1. A method of defining a contoured path for an automatic guidance system, the method comprising:

driving a vehicle along a path, wherein the driven path includes a plurality of path segments and driving along the path includes turning a rounded corner between consecutive path segments, executing a headland maneuver between consecutive path segments, or both, each of the path segments being straight or presenting one or more curved sections with a radius of curvature greater than a predetermined reference radius;

defining a plurality of contoured path segments corresponding to the driven path segments but excluding rounded corners between consecutive path segments and headland maneuvers between consecutive path segments;

for each contoured path segment, determining one or more intersection points with one or more other contoured path segments; and

defining the contoured path as a sequence of the intersecting contoured path segments, the contoured path having sharp corners where the contoured path segments intersect.

2. The method as set forth in claim 1, the step of defining the contoured path segments including extending the ends of at least one driven path segment based on the heading followed while driving the vehicle along the driven path segment.

3. The method as set forth in claim 1, further comprising identifying at least one of the start and end of a reference path segment by detecting a manual trigger by an operator of the vehicle while driving along the path.

4. The method as set forth in claim 1, further comprising identifying the end of a reference path segment by detecting the path turning through a radius of curvature less than a predetermined reference radius.

5. The method as set forth in claim 1, further comprising identifying an end of a reference path segment by detecting a crossing point of the driven path with itself.

6. The method as set forth in claim 1, the steps of defining the plurality of contoured path segments, determining the one or more intersection points, and defining the contoured path being performed automatically by the automatic guidance system as the vehicle is driven along the path.

7. The method as set forth in claim 1, the steps of defining the plurality of contoured path segments, determining the one or more intersection points, and defining the contoured path being performed automatically by the automatic guidance system while the guidance system is operating in a contour guidance mode, wherein the guidance system remains in the contour mode even when the vehicle transitions from one driven path segment to another.

8. A method of defining a contoured path for an automatic guidance system, the method comprising:

determining a reference path, the reference path including a plurality of path segments and rounded corners between consecutive path segments, each of the path segments being straight or presenting one or more curved sections with a radius of curvature greater than a predetermined reference radius and the rounded corners presenting a radius of curvature less than a predetermined reference radius;

defining a plurality of contoured path segments corresponding to the reference path segments but excluding rounded corners between consecutive path segments;

for each contoured path segment, determining one or more intersection points with one or more other contoured path segments;

defining the contoured path as a sequence of the intersecting contoured path segments, the contoured path having sharp corners where the contoured path segments intersect; and

automatically guiding a vehicle according to the contoured path.

9. The method as set forth in claim 8, the step of determining the reference path including receiving an existing reference path definition.

10. The method as set forth in claim 8, further comprising—

defining a subsequent path based on the contoured path, the subsequent path including a sequence of intersecting contoured path segments, the contoured path having sharp corners where the contoured path segments intersect, each of the subsequent path segments corresponding to one of the contoured path segments but being offset therefrom,

for each subsequent path segment presenting a curved section, compare a radius of curvature of the curved section to the predetermined reference radius, and

if the radius of curvature of the subsequent path segment is less than the predetermined reference radius, divide the subsequent path segment into two segments and replace the curved section with a sharp corner between the two segments.

11. An automatic guidance system associated with a vehicle, the system comprising:

a position determining mechanism;

a data storage device; and

a data processing device in communication with the position determining mechanism and the data storage device, the data processing device configured to—

as the vehicle drives along a path, define a plurality of contoured path segments corresponding to driven path segments but excluding rounded corners between consecutive driven path segments and headland maneuvers between consecutive driven path segments, each of the driven path segments being straight or presenting one or more curved sections with a radius of curvature greater than a predetermined reference radius;

for each contoured path segment, determine one or more intersection points with at least one other contoured path segment, and

define a contoured path as a sequence of the intersecting contoured path segments, the contoured path having sharp corners where the contoured path segments intersect.

12. The automatic guidance system as set forth in claim 11, the data processing device configured to define the contoured path segments by extending the ends of at least one driven path segment based on the heading followed by the vehicle driving along the driven path segment.

13. The automatic guidance system as set forth in claim 11, wherein the data processing device identifies at least one of the start and end of a contoured path segment in response to a manual trigger by an operator of the vehicle while driving along the path.

14. The automatic guidance system as set forth in claim 11, wherein the data processing device identifies at least one of the start and end of a contoured path segment in response to the path turning through a radius of curvature less than a predetermined reference radius.

15. The automatic guidance system as set forth in claim 11, wherein the data processing element identifies an end of a driven path segment in response to the driven path crossing itself.

16. The automatic guidance system as set forth in claim 11, the data processing device configured to automatically define the plurality of contoured path segments, determine the one or more intersection points, and define the contoured path as the vehicle is driven along the path.

17. The automatic guidance system as set forth in claim 11, the data processing device configured to automatically define the plurality of contoured path segments, determine the one or more intersection points, and define the contoured path while the guidance system is operating in a contour guidance mode, wherein the guidance system remains in the contour mode even when the vehicle transitions from one driven path segment to another.

18. The automatic guidance system as set forth in claim 11, further comprising a display configured to display only a portion of the contoured path proximate the vehicle.

19. The automatic guidance system as set forth in claim 11, the data processing device configured to generate a subsequent path based on the contoured path, the subsequent path comprising a plurality of path segments intersecting at sharp corners.

20. The automatic guidance system as set forth in claim 11, the data processing device configured to automatically select a guidance target by calculating angles to adjacent path segments and selecting a path segment corresponding to a smallest angle.

21. The automatic guidance system as set forth in claim 11, the data processing device configured to automatically select a guidance target by calculating distances between the vehicle'"'"'s position and intersection points of the contoured path and selecting an intersection point nearest the tractor as the guidance target.

22. The automatic guidance system as set forth in claim 11, the data processing device configured to automatically select a guidance target by calculating a perpendicular distance between the vehicle'"'"'s position and each of a plurality of path segments and selecting a path segment corresponding to the smallest perpendicular distance as the guidance target.

23. The automatic guidance system as set forth in claim 11, the data processing device further configured to—

receive a reference path definition, the reference path definition including a plurality of reference path segments and rounded corners between at least some consecutive reference path segments,

define a plurality of second contoured path segments corresponding to reference path segments but excluding rounded corners between consecutive reference path segments,

for each of the second contoured path segments, determine one or more intersection points with at least one other of the second contoured path segments, and

define a second contoured path as a sequence of the intersecting second contoured path segments, the second contoured path having sharp corners where the second contoured path segments intersect.

24. The automatic guidance system as set forth in claim 11, the data processing device further configured to—

create a reference path by adding offsets to known field boundary positions, the reference path definition including a plurality of reference path segments,

for each reference path segment, determine one or more intersection points with at least one other reference path segment, and

define a second contoured path as a sequence of the intersecting reference path segments, the second contoured path having sharp corners where the reference path segments intersect.