Human perception model for speed control performance

• US 7,895,135 B2
• Filed: 02/12/2007
• Issued: 02/22/2011
• Est. Priority Date: 02/12/2007
• Status: Active Grant

• Current Assignee: Deere & Company
• Original Assignee: Deere & Company
• Inventors: Norris, William Robert, Reid, John Franklin, Gilmore, Brian Joseph, Rornig, Bernard Edwin
• Primary Examiner(s): Holmes; Michael B.
• Assistant Examiner(s): Kim; David H
• Application Number:
  US11/673,638
• Publication Number:
  US 20080195569A1
• Time in Patent Office: 1,471 Days
• Field of Search: 706/52, 706 1- 9, 701/98, 701/44
• US Class Current: 706/3
• CPC Class Codes: F02D 2200/501 Vehicle speed
• CPC Class Codes: F02D 2200/606 Driving style, e.g. sporty or economic driving
• CPC Class Codes: F02D 2200/702 Road conditions
• CPC Class Codes: F02D 41/1404 Fuzzy logic control

Abstract

A human perception model for a speed control method obtains a steering angle, a velocity error and a distance error. The steering angle and a measure of operator aggressiveness are applied to the model. The output is defuzzified. The steering angle, the velocity error and the distance error are applied to fuzzy logic membership functions to produce an output that is applied to a velocity rule base. The measure of operator aggressiveness is input to the velocity rule base. The output from the velocity rule base is defuzzified to produce a speed signal.

Claims

1. A human perception model for a speed control method, comprising the steps of:

obtaining, by a vehicle control system, a steering angle;

obtaining, by the vehicle control system, a velocity error;

obtaining, by the vehicle control system, a distance error, wherein the distance error is a difference between a required path and a determined actual location;

establishing the required path which serves as an input to said obtaining a distance error step;

establishing required vehicle speed set points as an input to said obtaining a distance error step;

applying, by the vehicle control system, said steering angle, said velocity error and said distance error to fuzzy logic membership functions to produce an output that is applied to a velocity rule base;

inputting, by the vehicle control system, a measure of operator aggressiveness to said velocity rule base; and

defuzzifying, by the vehicle control system, an output from said velocity rule base to produce a speed signal.

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

3. The method of claim 2, further comprising the step of inputting an operator reaction time to said vehicle control unit.

4. The method of claim 1, further comprising the step of changing set points dependent on said distance error.

5. The method of claim 4, further comprising the step of using operator experience/perception information by said fuzzy logic membership functions.

6. The method claim 1, wherein said establishing the required path step also serves as an input to said obtaining a velocity error step.

7. The method of claim 1, wherein said establishing required vehicle speed set points step also serves as an input to said obtaining a velocity error 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 input to at least one of said obtaining a velocity error step and said obtaining a distance error step.

9. A human perception model for a speed control method, comprising the steps of:

applying, by a vehicle control system, a steering angle, a velocity error and a distance error to fuzzy logic membership functions to produce an output that IS applied to a velocity rule base, wherein the distance error is a difference between a required path and a determined actual location;

establishing the required path which serves as an input to obtain said distance error;

establishing required vehicle speed set points as an input to obtain said distance error;

inputting, by the vehicle control system, a measure of operator aggressiveness to said velocity rule base; and

defuzzifying, by the vehicle control system, an output from said velocity rule base to produce a speed signal.

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

11. The method of claim 10, further comprising the step of inputting an operator reaction time to said vehicle control unit.

12. The method of claim 9, further comprising the step of changing set points dependent on said distance error.

13. The method of claim 12, further comprising the step of using operator experience/perception information by said fuzzy logic membership functions.

14. The method of claim 9, wherein said establishing the required path step also serves as an input to obtain said velocity error.

15. The method of claim 9, wherein said establishing required vehicle speed set points step also serves as an input to obtain said velocity error.

16. The method of claim 15, further comprising the step of obtaining at least one of an orientation, a location and a velocity to input to obtain said velocity error and said distance error.