Perception model for trajectory following autonomous and human augmented steering control

• US 8,195,364 B2
• Filed: 02/12/2007
• Issued: 06/05/2012
• Est. Priority Date: 02/12/2007
• Status: Active Grant

• Current Assignee: Deere & Company
• Original Assignee: Deere & Company
• Inventors: Norris, William Robert, Romig, Bernard Edwin, Reid, John Franklin
• Primary Examiner(s): Tran, Khoi
• Assistant Examiner(s): Jen, Ian
• Application Number:
  US11/673,659
• Publication Number:
  US 20080195282A1
• Time in Patent Office: 1,940 Days
• Field of Search: 701/19, 701/27, 701/44, 701/301, 701/214, 706/1, 706/2, 706/23, 703/8
• US Class Current: 701/44
• CPC Class Codes: B60W 2050/0057 Frequency analysis, spectral techniques or transforms
• CPC Class Codes: B62D 1/28 non-mechanical , e.g. following a line or other known markers
• CPC Class Codes: G05B 13/0275 using fuzzy logic only
• CPC Class Codes: G05D 1/0278 using satellite positioning signals, e.g. GPS

Abstract

A steering control method including the steps of obtaining a heading error, obtaining a velocity value, obtaining a distance error, applying the heading error and defuzzifying an output from a steering rule base. The velocity value and the distance error are applied along with the heading error to fuzzy logic membership functions to produce an output that is applied to a steering rule base. An output from the steering rule base is defuzzified to produce a steering signal.

Claims

1. A steering control method, comprising the steps of:

obtaining a heading error;

obtaining a velocity value;

obtaining a distance error, said velocity value and said distance error being determined from a combination of a GPS position and a required path;

applying said heading error, said velocity value and said distance error to fuzzy logic membership functions to produce an output that is applied to a steering rule base; and

defuzzifying an output from said steering ruling base to produce a steering signal;

establishing a required path which serves as an input to said obtaining distance error and velocity value step by a processor.

2. The method of claim 1, further comprising the step of receiving said steering signal by a vehicle control unit.

3. The method of claim 1, further comprising the step of generating at least one of said heading error, said velocity value and said distance error by comparing a required path to a current position of the vehicle.

4. The method of claim 1, further comprising the step of establishing a required path which serves as an input to said obtaining a distance error step.

5. The method of claim 4, wherein said establishing a required path step also serves as an input to said obtaining a velocity value step.

6. The method of claim 1, further comprising the step of establishing a required path which serves as an input to said obtaining a distance error step.

7. The method of claim 6, wherein said establishing a required path step also serves as an input to said obtaining a velocity value step.

8. The method of claim 7, further comprising the step of obtaining at least one of an orientation, a location and a velocity to serve as an input to at least one of said obtaining a velocity value step and said obtaining a distance error step.

17. The method of claim 1, further comprising the step of obtaining a steering angle, and applying said steering angle to fuzzy logic membership functions to produce an output that is applied to a steering rule base.

9. A steering control method of a vehicle, the method comprising the steps of:

applying a steering angle, a velocity value, a heading error and a distance error to fuzzy logic membership functions to produce an output that is applied to a steering rule base; and

defuzzifying an output from said steering rule base to produce a steering signal;

establishing a required path which serves an input to said distance error and a velocity value by a processor.

10. The method of claim 9, further comprising the step of receiving said steering signal by a vehicle control unit.

11. The method of claim 9, further comprising the step of generating at least one of said steering angle, said velocity value, said heading error and said distance error by comparing a required path to a current position of the vehicle.

12. The method of claim 9, further comprising the step of establishing a required path which serves as an input to said obtaining a distance error step.

13. The method of claim 12, wherein said establishing a required path step also serves as an input to obtain said heading error.

14. The method of claim 12, further comprising the step of establishing required vehicle speed set points as an input to obtain said distance error.

15. The method of claim 12, further comprising the step of using feedback information to establish a current position of the vehicle to obtain said distance error.

16. The method of claim 15, wherein said using feedback information step also serves as an input to said obtaining said heading error.