Direct modification of DGPS information with inertial measurement data

• US 6,789,014 B1
• Filed: 05/09/2003
• Issued: 09/07/2004
• Est. Priority Date: 05/09/2003
• Status: Expired due to Term

• Current Assignee: Deere & Company
• Original Assignee: Deere & Company
• Inventors: Pickett, Terence, Mercer, Dave, Nelson, Frederick William, Rekow, Andrew Karl Wilhelm
• Primary Examiner(s): Black, Thomas G.
• Assistant Examiner(s): Hernandez, Olga
• Application Number:
  US10/435,067
• Time in Patent Office: 487 Days
• Field of Search: 701/214, 701/200, 701/202, 701/205, 701/207, 701/210, 701/213, 701/220, 701/221, 701/224, 701/36, 701/41, 701/1, 701/23, 701/26, 731/78.R, 340/988, 340/995.21, 180/9.38, 180/9.44
• US Class Current: 701/214
• CPC Class Codes: G01C 21/165 combined with non-inertial navigation instruments
• CPC Class Codes: G01S 19/41 Differential correction, e.g. DGPS [differential GPS]
• CPC Class Codes: G05D 1/027 comprising intertial navigation means, e.g. azimuth detector inertial navigation G01C21/16; inertial navigation combined with non-inertial navigation instruments G01C21/165
• CPC Class Codes: G05D 1/0278 using satellite positioning signals, e.g. GPS

Abstract

A global positioning system based navigation system for a ground vehicle, in particular an agricultural ground vehicle such as a tractor, combine, sprayer, or the like, includes an inertial compensation assembly that provides inertial augmentation to compensate global positioning system based navigation information such as position, course, and track spacing for errors caused by variation of ground vehicle attitude (i.e., roll and yaw) over non-level terrain.

Claims

1. A navigation system for a ground vehicle, comprising:

a global positioning system receiver assembly for receiving a positioning signal from a global positioning system and generating navigation information for the ground vehicle, the navigation information including a position and course for the ground vehicle;

a navigation control system interconnected with the global positioning system receiver assembly for steering the ground vehicle; and

an inertial compensation assembly coupled to the global positioning system receiver assembly and the navigation control system for replacing the position and course with a corrected position and a corrected course that are inertially compensated for roll and yaw of the ground vehicle to provide corrected navigation information to the navigation control system, the inertial compensation assembly comprising a gyroscope assembly for measuring a yaw rate of the ground vehicle and an accelerometer assembly for measuring a lateral acceleration of the ground vehicle, the inertial compensation assembly using the measured yaw rate and lateral acceleration for generating the corrected position and course by calculating an off-track distance for the ground vehicle from the lateral acceleration generated by the accelerometer assembly and a distance due to high speed acceleration of the ground vehicle, the distance due to high speed acceleration being determined from changes in the position of the ground vehicle with respect to the course of the ground vehicle.

wherein the navigation control system uses the corrected navigation information for steering the ground vehicle.

2. The navigation system as claimed in claim 1, wherein the inertial compensation assembly calculates a gyroscopic course from the yaw rate measured by the gyroscope assembly.

3. The navigation system as claimed in claim 2, wherein the inertial compensation unit determines the corrected course using the equation:

4. The navigation system as claimed in claim 1, wherein the gyroscope assembly comprises a single yaw gyroscope.

5. The navigation system as claimed in claim 1, wherein the inertial compensation assembly determines the off-track distance using the equation:

6. The navigation system as claimed in claim 1, wherein the accelerometer assembly comprises a single accelerometer.

7. The navigation system as claimed in claim 1, wherein the inertial compensation assembly further calculates the slope of the non-level terrain from the measured lateral acceleration of the ground vehicle, the slope being added to the corrected navigation information.

8. The navigation system as claimed in claim 7, wherein the navigation control system a uses the slope to determine the effective track spacing of an implement towed by the ground vehicle.

9. The navigation system as claimed in claim 8, wherein the effective track spacing is calculated by the equation:

10. A method for steering a ground vehicle traversing non-level terrain, comprising:

receiving a positioning signal from a global positioning system;

generating navigation information for the ground vehicle, the navigation information including a position and course for the ground vehicle;

replacing the position and course stripped from the navigation information with a corrected position and a corrected course that are inertially compensated for roll and yaw of the ground vehicle for providing corrected navigation information; and

steering the ground vehicle using the corrected navigation information,

wherein the step of steering the ground vehicle using the corrected navigation information comprises steering the ground vehicle so that the ground vehicle follows a track substantially parallel to a previously navigated track.

11. The method as claimed in claim 10, wherein the step of replacing the position and course stripped from the navigation information comprises determining a yaw angle for the ground vehicle using a gyroscope assembly and determining lateral acceleration of the ground vehicle using an accelerometer assembly, the lateral acceleration and the yaw angle being used for generating the corrected position and course.

12. The method as claimed in claim 11, further comprising calculating a yaw rate and a gyroscopic course from the yaw angle.

13. The method as claimed in claim 12, wherein the corrected course is determined using the equation:

14. The method as claimed in claim 11, wherein the gyroscope assembly comprises a single yaw gyroscope.

15. The method as claimed in claim 11, wherein the step of replacing the position and course stripped from the navigation information comprises calculating an off-track distance for the ground vehicle from the lateral acceleration generated by the accelerometer assembly and a distance due to high speed acceleration of the ground vehicle, the distance due to high speed acceleration being determined from changes in the position of the ground vehicle with respect to the course of the ground vehicle.

16. The method as claimed in claim 15, wherein the off-track distance is determined using the equation:

17. The method as claimed in claim 11, wherein the accelerometer assembly comprises a single accelerometer.

18. The method as claimed in claim 10, further comprising calculating the slope of non-level terrain, the slope being added to the corrected navigation information.

19. The method as claimed in claim 18, further comprising determining an effective track spacing of an implement towed by the ground vehicle using the slope.

20. The method as claimed in claim 19, wherein the effective track spacing is calculated by the formula:

21. An inertial compensation assembly for a navigation system of a ground vehicle, the navigation system including a global positioning system receiver assembly for receiving a positioning signal from a global positioning system and generating navigation information for the ground vehicle and a navigation control system for steering the ground vehicle, the inertial compensation assembly comprising:

a gyroscope assembly for determining a yaw angle for the ground vehicle;

an accelerometer assembly for determining a lateral acceleration of the ground vehicle; and

a processing assembly coupled to the gyroscope assembly and accelerometer assembly for replacing the position and course information with corrected position and course information to provide corrected navigation information to the navigation control system for steering the ground vehicle,

wherein the processor assembly generates the corrected position and course information using the yaw angle measured by the gyroscope assembly and the lateral acceleration measured by the accelerometer assembly so that the corrected navigation information is inertially compensated for roll and yaw of the ground vehicle over non-level terrain.

22. The inertial compensation assembly as claimed in claim 21, wherein the processing assembly calculates a yaw rate and a gyroscopic course from the yaw angle measured by the gyroscope assembly.

23. The inertial compensation assembly as claimed in claim 22, wherein the processing assembly determines the corrected course using the equation:

24. The inertial compensation assembly as claimed in claim 21, wherein the gyroscope assembly comprises a single yaw gyroscope.

25. The inertial compensation assembly as claimed in claim 21, wherein the processing assembly calculates an off-track distance for the ground vehicle from the lateral acceleration generated by the accelerometer assembly and a distance due to high speed acceleration of the ground vehicle, the distance due to high speed acceleration being determined from changes in the position of the ground vehicle with respect to the course of the ground vehicle.

26. The inertial compensation assembly as claimed in claim 25, wherein the processing assembly determines the off-track distance using the equation:

27. The inertial compensation assembly as claimed in claim 21, wherein the accelerometer assembly comprises a single accelerometer.

28. The inertial compensation assembly as claimed in claim 21, wherein the processing assembly further calculates the slope of the non-level terrain, the slope being added to the corrected navigation information.

29. A navigation system for a ground vehicle, comprising:

a global positioning system receiver assembly for receiving a positioning signal from a global positioning system and generating navigation information for the ground vehicle, the navigation information including a position and course for the ground vehicle;

a navigation control system interconnected with the global positioning system receiver assembly for steering the ground vehicle; and

an inertial compensation assembly coupled to the global positioning system receiver assembly and the navigation control system for replacing the position and course with a corrected position and a corrected course that are inertially compensated for roll and yaw of the ground vehicle to provide corrected navigation information to the navigation control system, the inertial compensation assembly comprising a gyroscope assembly for measuring a yaw rate of the ground vehicle and an accelerometer assembly for measuring a lateral acceleration of the ground vehicle, the inertial compensation assembly using the measured yaw rate and lateral acceleration for generating the corrected position and course using the equation;

30. The navigation system as claimed in claim 29, wherein the gyroscope assembly comprises a single yaw gyroscope.

31. The navigation system as claimed in claim 29, wherein the inertial compensation assembly calculates an off-track distance for the ground vehicle from the lateral acceleration generated by the accelerometer assembly and a distance due to high speed acceleration of the ground vehicle, the distance due to high speed acceleration being determined from changes in the position of the ground vehicle with respect to the course of the ground vehicle.

32. The navigation system as claimed in claim 31, wherein the inertial compensation assembly determines the off-track distance using the equation:

33. The navigation system as claimed in claim 29, wherein the accelerometer assembly comprises a single accelerometer.

34. The navigation system as claimed in claim 29, wherein the inertial compensation assembly further calculates the slope of the non-level terrain from the measured lateral acceleration of the ground vehicle, the slope being added to the corrected navigation information.

35. The navigation system as claimed in claim 34, wherein the navigation control system a uses the slope to determine the effective track spacing of an implement towed by the ground vehicle.

36. The navigation system as claimed in claim 35, wherein the effective track spacing is calculated by the equation:

37. A navigation system for a ground vehicle, comprising:

a global positioning system receiver assembly for receiving a positioning signal from a global positioning system and generating navigation information for the ground vehicle, the navigation information including a position and course for the ground vehicle;

a navigation control system interconnected with the global positioning system receiver assembly for steering the ground vehicle; and

an inertial compensation assembly coupled to the global positioning system receiver assembly and the navigation control system for replacing the position and course with a corrected position and a corrected course that are inertially compensated for roll and yaw of the ground vehicle to provide corrected navigation information to the navigation control system, the inertial compensation assembly calculating the slope of the non-level terrain from the measured lateral acceleration of the ground vehicle, the slope being added to the corrected navigation information,

wherein the navigation control system uses the corrected navigation information for steering the ground vehicle.

38. The navigation system as claimed in claim 37, wherein the inertial compensation assembly comprises a gyroscope assembly for measuring a yaw rate of the ground vehicle and an accelerometer assembly for measuring a lateral acceleration of the ground vehicle, the inertial compensation assembly using the measured yaw rate and lateral acceleration for generating the corrected position and course.

39. The navigation system as claimed in claim 38, wherein the inertial compensation assembly calculates a gyroscopic course from the yaw rate measured by the gyroscope assembly.

40. The navigation system as claimed in claim 39, wherein the inertial compensation unit determines the corrected course using the equation:

41. The navigation system as claimed in claim 38, wherein the gyroscope assembly comprises a single yaw gyroscope.

42. The navigation system as claimed in claim 38, wherein the inertial compensation assembly calculates an off-track distance for the ground vehicle from the lateral acceleration generated by the accelerometer assembly and a distance due to high speed acceleration of the ground vehicle, the distance due to high speed acceleration being determined from changes in the position of the ground vehicle with respect to the course of the ground vehicle.

43. The navigation system as claimed in claim 42, wherein the inertial compensation assembly determines the off-track distance using the equation:

44. The navigation system as claimed in claim 38, wherein the accelerometer assembly comprises a single accelerometer.

45. The navigation system as claimed in claim 37, wherein the effective track spacing is calculated by the equation:

46. A method for steering a ground vehicle traversing non-level terrain, comprising:

receiving a positioning signal from a global positioning system;

generating navigation information for the ground vehicle, the navigation information including a position and course for the ground vehicle;

replacing the position and course stripped from the navigation information with a corrected position and a corrected course that are inertially compensated for roll and yaw of the ground vehicle for providing corrected navigation information; and

steering the ground vehicle using the corrected navigation information,

wherein the step of replacing the position and course stripped from the navigation information comprises determining a yaw angle for the ground vehicle using a gyroscope assembly and determining lateral acceleration of the ground vehicle using an accelerometer assembly, the lateral acceleration and the yaw angle being used for generating the corrected position and course.

47. The method as claimed in claim 46, wherein the step of steering the ground vehicle using the corrected navigation information comprises steering the ground vehicle so that the ground vehicle follows a track substantially parallel to a previously navigated track.

48. The method as claimed in claim 46, further comprising calculating a yaw rate and a gyroscopic course from the yaw angle.

49. The method as claimed in claim 48, wherein the corrected course is determined using the equation:

50. The method as claimed in claim 46, wherein the gyroscope assembly comprises a single yaw gyroscope.

51. The method as claimed in claim 46, wherein the step of replacing the position and course stripped from the navigation information comprises calculating an off-track distance for the ground vehicle from the lateral acceleration generated by the accelerometer assembly and a distance due to high speed acceleration of the ground vehicle, the distance due to high speed acceleration being determined from changes in the position of the ground vehicle with respect to the course of the ground vehicle.

52. The method as claimed in claim 51, wherein the off-track distance is determined using the equation:

53. The method as claimed in claim 46, wherein the accelerometer assembly comprises a single accelerometer.

54. The method as claimed in claim 46, further comprising calculating the slope of non-level terrain, the slope being added to the corrected navigation information.

55. The method as claimed in claim 54, further comprising determining an effective track spacing of an implement towed by the ground vehicle using the slope.

56. The method as claimed in claim 55, wherein the effective track spacing is calculated by the formula:

57. A method for steering a ground vehicle traversing non-level terrain, comprising:

receiving a positioning signal from a global positioning system;

generating navigation information for the ground vehicle, the navigation information including a position and course for the ground vehicle;

replacing the position and course stripped from the navigation information with a corrected position and a corrected course that are inertially compensated for roll and yaw of the ground vehicle for providing corrected navigation information;

calculating the slope of non-level terrain, the slope being added to the corrected navigation information; and

steering the ground vehicle using the corrected navigation information.

58. The method as claimed in claim 57, wherein the step of steering the ground vehicle using the corrected navigation information comprises steering the ground vehicle so that the ground vehicle follows a track substantially parallel to a previously navigated track.

59. The method as claimed in claim 57, wherein the step of replacing the position and course stripped from the navigation information comprises determining a yaw angle for the ground vehicle using a gyroscope assembly and determining lateral acceleration of the ground vehicle using an accelerometer assembly, the lateral acceleration and the yaw angle being used for generating the corrected position and course.

60. The method as claimed in claim 59, further comprising calculating a yaw rate and a gyroscopic course from the yaw angle.

61. The method as claimed in claim 60, wherein the corrected course is determined using the equation:

62. The method as claimed in claim 59, wherein the gyroscope assembly comprises a single yaw gyroscope.

63. The method as claimed in claim 59, wherein the step of replacing the position and course stripped from the navigation information comprises calculating an off-track distance for the ground vehicle from the lateral acceleration generated by the accelerometer assembly and a distance due to high speed acceleration of the ground vehicle, the distance due to high speed acceleration being determined from changes in the position of the ground vehicle with respect to the course of the ground vehicle.

64. The method as claimed in claim 63, wherein the off-track distance is determined using the equation:

65. The method as claimed in claim 59, wherein the accelerometer assembly comprises a single accelerometer.

66. The method as claimed in claim 57, further comprising determining an effective track spacing of an implement towed by the ground vehicle using the slope.

67. The method as claimed in claim 66, wherein the effective track spacing is calculated by the formula: