Method and system for vehicular guidance using a crop image

• US 20070001096A1
• Filed: 12/16/2005
• Published: 01/04/2007
• Est. Priority Date: 07/01/2005
• Status: Active Grant

• Current Assignee: Deere & Company, Kansas State University Research Foundation
• Original Assignee: Deere & Company, Kansas State University Research Foundation
• Inventors: Han, Shufeng, Wei, Jiantao
• Granted Patent: US 7,684,916 B2
• Time in Patent Office: Days
• US Class Current: 250/208.100
• CPC Class Codes: A01B 69/001 Steering by means of optical assistance, e.g. television cameras steering devices for road marking vehicles E01C23/163

Abstract

An imaging device collects color image data to facilitate distinguishing crop image data from background data. A definer defines a series of scan line segments generally perpendicular to a transverse axis of the vehicle or of the imaging device. An intensity evaluator determines scan line intensity data for each of the scan line segments. An alignment detector identifies a preferential heading of the vehicle that is generally aligned with respect to a crop feature, associated with the crop image data, based on the determined scan line intensity meeting or exceeding a maximum value or minimum threshold value. A reliability estimator estimates a reliability of the vehicle heading based on compliance with an intensity level criteria associated with one or more crop rows.

Claims

1. A method of guiding a vehicle, the method comprising:

collecting color image data to distinguish crop image data from background image data;

defining a series of scan line segments generally perpendicular to a transverse axis of the vehicle or of an imaging system;

determining a scan line intensity for each of the scan lines; and

identifying a preferential heading of the vehicle that is generally aligned with respect to a crop feature, associated with the crop image data, based on the determined scan line intensity meeting or exceeding a maximum value or minimum threshold value; and

estimating a reliability of the vehicle heading based on compliance with an intensity level criteria associated with one or more crop rows.

2. The method according to claim 1 further comprising:

determining a first intensity value associated with a first crop row and a second intensity value associated with a second crop row; and

considering vision guidance data unreliable for a minimum time period if the first intensity value differs from the second intensity value by more than a minimum threshold.

3. The method according to claim 1 further comprising:

determining a spacing between a first crop row and a second crop row; and

considering vision guidance data unreliable for a minimum time period if the spacing does not fall within a defined row width range.

4. The method according to claim 1 further comprising:

determining a maximum intensity value for the first crop row and the second crop row; and

considering vision guidance data unreliable for a minimum time period if the maximum intensity value is not greater than a certain threshold value.

5. The method according to claim 1 further comprising:

determining a first intensity value associated with a first crop row and a second intensity value associated with a second crop row;

determining a spacing between a first crop row and a second crop row; and

determining a maximum intensity value for the first crop row and the second crop row; and

considering vision guidance data reliable for a time period if the first intensity value does not differ from the second intensity value by more than a minimum threshold, if the determined spacing between the first crop row and the falls within a defined width range, and if the maximum intensity value is greater than a certain threshold value.

6. The method according to claim 1 further comprising:

determining a first intensity value associated with a first crop row and a second intensity value associated with a second crop row; and

applying alternate guidance data other than vision guidance data for a minimum time period if the first intensity value differs from the second intensity value by more than a minimum threshold.

7. The method according to claim 1 further comprising:

determining a spacing between a first crop row and a second crop row; and

applying alternate guidance data other than vision guidance data for a minimum time period if the spacing does not fall within a defined row width range.

8. The method according to claim 1 further comprising:

determining a maximum intensity value for the first crop row and the second crop row; and

applying alternate guidance data other than vision guidance data for a minimum time period if the maximum intensity value is not greater than a certain threshold value.

9. The method according to claim 1 further comprising:

determining a first intensity value associated with a first crop row and a second intensity value associated with a second crop row; and

considering vision guidance data unreliable for a minimum time period if the first intensity value and the second intensity value do not comply with the individual predetermined threshold, an aggregate predetermined threshold, or both.

10. The method according to claim 1 further comprising:

determining an offset from a desired path; and

determining the vision guidance data is reliable if the determined offset is less than or equal to a maximum offset value.

11. A system of guiding a vehicle, the system comprising:

an imaging device for collecting color image data to distinguish crop image data from background image data;

a definer for defining a series of scan line segments generally perpendicular to a transverse axis of the vehicle or of an imaging system;

an intensity evaluator for determining a scan line intensity for each of the scan lines; and

an alignment detector for identifying a preferential heading of the vehicle that is generally aligned with respect to a crop feature, associated with the crop image data, based on the determined scan line intensity meeting or exceeding a maximum value or minimum threshold value; and

a reliability estimator for estimating a reliability of the vehicle heading based on compliance with an intensity level criteria associated with one or more crop rows.

12. The system according to claim 11 wherein the intensity evaluator determines a first intensity value associated with a first crop row and a second intensity value associated with a second crop row;

and

the reliability estimator considering vision guidance data unreliable for a minimum time period if the first intensity value differs from the second intensity value by more than a minimum threshold.

13. The system according to claim 11 wherein the intensity evaluator determines a spacing between a first crop row and a second crop row;

and

the reliability estimator considering vision guidance data-unreliable for a minimum time period if the spacing does not fall within a defined row width range.

14. The system according to claim 11 wherein the intensity evaluator determines a maximum intensity value for the first crop row and the second crop row;

and

the reliability estimator considering vision guidance data unreliable for a minimum time period if the maximum intensity value is not greater than a certain threshold value.

15. The system according to claim 11 wherein the intensity evaluator determines a first intensity value associated with a first crop row and a second intensity value associated with a second crop row, the intensity evaluator determining a maximum intensity value for the first crop row and the second crop row;

a data processor determining a spacing between a first crop row and a second crop row; and

the reliability estimator considering vision guidance data reliable for a time period if the first intensity value does not differ from the second intensity value by more than a minimum threshold, if the determined spacing between the first crop row falls within a defined width range, and if the maximum intensity value is greater than a certain threshold value.

16. The system according to claim 11 wherein the intensity evaluator determines a first intensity value associated with a first crop row and a second intensity value associated with a second crop row:

and

a vehicle guidance controller applying alternate guidance data other than vision guidance data for a minimum time period if the first intensity value differs from the second intensity value by more than a minimum threshold.

17. The system according to claim 11 wherein the intensity evaluator determines a spacing between a first crop row and a second crop row;

and

a vehicle guidance controller applying alternate guidance data other than vision guidance data for a minimum time period if the spacing does not fall within a defined row width range.

18. The system according to claim 11 wherein the intensity evaluator determines a maximum intensity value for the first crop row and the second crop row;

and

a vehicle guidance controller applying alternate guidance data other than vision guidance data for a minimum time period if the maximum intensity value is not greater than a certain threshold value.

19. The system according to claim 11 wherein the intensity evaluator determines a first intensity value associated with a first crop row and a second intensity value associated with a second crop row;

and

a vehicle guidance controller considering vision guidance data unreliable for a minimum time period if the first intensity value and the second intensity value do not comply with the individual predetermined threshold, an aggregate predetermined threshold, or both.

20. The system according to claim 11 further comprising:

an offset calculator for determining an offset from a desired path; and

a reliability estimator for determining the vision guidance data is reliable if the determined offset is less than or equal to a maximum offset value.