Method and system for guidance of off-road vehicles

Patent metadata

Field	Value
Publication number	US-9921064-B2
Application number	US-201514977825-A
Country	US
Kind code	B2
Filing date	Dec 22, 2015
Priority date	Oct 30, 2015
Publication date	Mar 20, 2018
Grant date	Mar 20, 2018

Abstract

A method and system for guidance of an off-road vehicle comprises a crop row sensor for sensing position data for one or more crop rows. A primary guidance path of the vehicle is determined based on the sensed position data for the one or more crop rows if there not a material gap in the crop row for the current location of the vehicle. Alternately or cumulatively, a secondary guidance path of the vehicle is determined based on a historic path heading of the vehicle if there is the material gap in a crop row for a current location of the vehicle.

First claim

The invention claimed is:

1. A method for guidance of an off-road vehicle, the method comprising:
sensing, by a row sensor, position data for one or more crop rows;
determining, by an electronic data processor, a primary guidance path of the vehicle based on the sensed position data for the one or more crop rows if there not a material gap in the crop row for the current location of the vehicle; and
determining, by the data processor, a secondary guidance path of the vehicle based on a historic path heading of the vehicle if there is the material gap in a crop row for a current location of the vehicle, wherein the determining of the secondary guidance path is based on a running average of the historic path heading consistent with a curvature limit of a curved path plan if the estimated curvature of the historic path heading is greater than, or equal to, a threshold.

2. The method according to claim 1 wherein the determining of the primary guidance path is based on a central position between two adjacent crop rows that are sensed by arms of contact sensors.

3. The method according to claim 1 wherein the determining of the secondary guidance path is based on the historic path heading consistent with headings estimated by a location-determining receiver for corresponding historic locations of the vehicle.

4. The method according to claim 1 wherein the estimated curvature is determined based on the following equation: C=ΔP/D, where C is the curvature, ΔP is the path heading change, and D is the path distance.

5. The method according to claim 4 wherein the threshold is equal to approximately 0.5.

6. The method according to claim 1 wherein the determining of the secondary guidance path is based on a running average of the historic path heading consistent with a linear limit of a curved path plan if the estimated curvature of the historic path heading is less than a threshold.

7. The method according to claim 1 wherein the estimated curvature is determined based on the following equation: C=ΔP/D, where C is the curvature, ΔP is the path heading change, and D is the path distance.

8. The method according to claim 4 wherein the threshold is equal to approximately 0.5.

9. The method according to claim 1 further comprising:
determining the primary guidance path or the secondary guidance path based on a difference between a current path heading and a projected path heading based on a running average of the historic path heading.

10. The method according to claim 9 further comprising:
steering a vehicle based on the determined difference.

11. A system for guidance of an off-road vehicle, the method comprising:
a row sensor for sensing position data for one or more crop rows;
a crop row sensing module for determining a primary guidance path of the vehicle based on the sensed position data for the one or more crop rows if there not a material gap in the crop row for the current location of the vehicle;
a data processor for determining a secondary guidance path of the vehicle based on a historic path heading of the vehicle if there is the material gap in a crop row for a current location of the vehicle; and
a curvature module for determining of the secondary guidance path based on a running average of the historic path heading consistent with a curvature limit of a curved path plan if the estimated curvature of the historic path heading is greater than, or equal to, a threshold.

12. The system according to claim 11 wherein the row sensor further comprises a pair of crop row sensors with contact arms for contacting one or more plants in the one or more crop rows and producing an electrical signal associated with such contacting of the one or more plants, wherein the crop row sensing module is adapted to determine a central position between two adjacent crop rows that are sensed by the pair of the crop crow sensors.

13. The system according to claim 11 further comprising:
a location-determining receiver for determining of the secondary guidance path based on the historic path heading consistent with headings estimated by a location-determining receiver for corresponding historic locations of the vehicle.

14. The system according to claim 11 wherein:
the data processor arranged to determine the estimated curvature in accordance with the following equation: C=ΔP/D, where C is the curvature, ΔP is the path heading change, and D is the path distance.

15. The system according to claim 11 wherein the threshold is equal to approximately 0.5.

16. The system according to claim 11 further comprising:
a linear module for the determining of the secondary guidance path based on a running average of the historic path heading consistent with a linear limit of a curved path plan if the estimated curvature of the historic path heading is less than a threshold.

17. The system according to claim 16 wherein:
the data processor is arranged to determine the estimated curvature in accordance with the following equation: C=ΔP/D, where C is the curvature, ΔP is the path heading change, and D is the path distance.

18. The system according to claim 16 wherein the threshold is equal to approximately 0.5.

19. The system according to claim 11 wherein:
the data processor is adapted to determine the primary guidance path or the secondary guidance path based on a difference between a current path heading and a projected path heading based on a running average of the historic path heading.

20. The system according to claim 11 further comprising:
a steering controller for steering a vehicle based on the determined difference.

Assignees

• Deere & Co

Inventors

• Schleicher Tyler D

Classifications

• G01C21/14 Primary

  by recording the course traversed by the object (G01C21/16 takes precedence) · CPC title

• G01C21/10 Primary

  by using measurements of speed or acceleration (G01C21/24, G01C21/26 take precedence) · CPC title

• A01B69/008

  automatic · CPC title

• G05D1/0212

  with means for defining a desired trajectory (involving a plurality of land vehicles G05D1/0287) · CPC title