All-terrain error correction

• US 6,104,339 A
• Filed: 08/19/1998
• Issued: 08/15/2000
• Est. Priority Date: 08/19/1998
• Status: Expired due to Term

• Current Assignee: Trimble Navigation Limited (Trimble Inc.)
• Original Assignee: Trimble Navigation Limited (Trimble Inc.)
• Inventors: Nichols, Mark Edward
• Primary Examiner(s): Tarcza, Thomas H.
• Assistant Examiner(s): MULL, FRED H
• Application Number:
  US09/136,813
• Time in Patent Office: 727 Days
• Field of Search: 342/357.06, 342/357.17, 342/357.13, 342/357.08, 342/457, 701/205
• US Class Current: 342/357.27
• CPC Class Codes: G01S 19/41 Differential correction, e.g. DGPS [differential GPS]
• CPC Class Codes: G01S 19/43 using carrier phase measurements, e.g. kinematic positioning; using long or short baseline interferometry
• CPC Class Codes: G01S 19/47 the supplementary measurement being an inertial measurement, e.g. tightly coupled inertial

Abstract

The real time differential satellite navigational system integrated with the tilt measurement system is disclosed. The integrated positioning system allows one to perform the real time precise navigation of a mobile unit in a variable tilt environment. In another embodiment, the map generating system is disclosed. The map generating system utilizes the low cost post-processing differential GPS receiver. The map generating system allows one to record the map of an actual area covered by a mobile unit in a variable tilt environment.

Claims

1. A positioning system comprising:

a satellite positioning system (SATPS) receiver fixed to a mobile unit;

wherein said SATPS receiver is configured to perform three dimensional coordinates measurements of said mobile unit; and

a tilt angle measurement device integrated with said SATPS receiver;

wherein said tilt measurement device is configured to perform tilt coordinates measurements of said mobile unit;

wherein said three dimensional coordinates and said tilt coordinates of said mobile unit are utilized to calculate real time three dimensional coordinates of an implement mounted in said mobile unit.

2. The system of claim 1 further comprising:

a SATPS/tilt integrated navigational computer;

wherein said SATPS/tilt integrated navigational computer is configured to calculate three dimensional coordinates of said implement by solving a set of geometrical equations including said three dimensional coordinates of said mobile unit, said tilt coordinates of said mobile unit that are measured synchronously with said three dimensional coordinates of said mobile unit, and a distance between said SATPS receiver and said implement.

3. The system of claim 1, wherein said SATPS receiver further comprises:

an RTK differential GPS receiver.

4. The system of claim 1, wherein said SATPS receiver further comprises:

a differential GPS receiver.

5. The system of claim 1, wherein said SATPS receiver further comprises:

a GLONASS receiver.

6. The system of claim 1, wherein said SATPS receiver further comprises:

a combined GPS/GLONASS receiver.

7. The system of claim 1, wherein said tilt angle measurement device further comprises:

an electronic tilt measurement device.

8. The system of claim 7, wherein said electronic tilt measurement device further comprises:

a single angle measurement device; and

wherein the relationship between said single angle coordinate and the heading of said mobile unit is known.

9. The system of claim 7, wherein said electronic tilt measurement device further comprises:

a dual angle measurement device; and

wherein the relationship between said dual angle coordinates and the heading of said mobile unit is known.

10. The system of claim 1, wherein said mobile unit further comprises:

a farm tractor towing an implement; and

wherein said implement further comprises;

a spray unit.

11. A map generating system comprising:

a satellite positioning system (SATPS) receiver mounted in a housing means of a mobile unit, wherein said SATPS receiver is configured to perform three dimensional coordinates measurements of said mobile unit;

a tilt angle measurement device integrated with said SATPS receiver, wherein said tilt measurement device is configured to perform tilt coordinates measurements of said mobile unit;

a SATPS/tilt integrated navigational computer, wherein said SATPS/tilt integrated navigational computer is configured to calculate three dimensional coordinates of an implement mounted in said mobile unit by solving a set of geometrical equations including said three dimensional coordinates of said mobile unit, said tilt coordinates of said mobile unit that are measured synchronously with said three dimensional coordinates of said mobile unit, and a distance between said SATPS receiver and said implement; and

a memory unit configured to record three dimensional coordinates of said implement in order to generate a map of an actual area covered by said implement.

12. The system of claim 11;

wherein said (SATPS) receiver further comprises;

a differential GPS post-processing receiver;

and wherein said mobile unit further comprises;

a farm tractor towing an implement;

and wherein said implement further comprises;

a spray unit;

and wherein said map generating system generates a map of an actually sprayed area of a field with variable tilt.

13. A method of coordinate measurement comprising the steps of:

performing three dimensional coordinates measurements of a mobile unit by using a satellite positioning system (SATPS) receiver mounted in a housing means of said mobile unit;

performing tilt coordinates measurements of said mobile unit by using a tilt angle measurement device integrated with said SATPS receiver; and

calculating three dimensional coordinates of an implement mounted in said mobile unit by utilizing said three dimensional coordinates and said tilt coordinates of said mobile unit.

14. The method of claim 13;

wherein said step of performing tilt coordinates measurements of said mobile unit further comprises the step of;

synchronizing the tilt coordinates measurements with a SATPS clock.

15. The method of claim 14;

wherein said step of calculating three dimensional coordinates of said implement further comprises the step of;

solving a set of geometrical equations including said three dimensional coordinates of said mobile unit, said tilt coordinates of said mobile unit, and a distance between said SATPS receiver and said implement by using a SATPS/tilt integrated navigational computer.

16. The method of claim 13, wherein said step of performing tilt coordinates measurements further comprises the step of:

determining the relationship between tilt coordinates and the heading of said mobile unit.

17. The method of claim 16, wherein said step of determining the relationship between tilt coordinates and the heading of said mobile unit further comprises the steps of:

obtaining a first set of three dimensional coordinates of said SATPS receiver at a first location of said mobile unit;

obtaining a second set of three dimensional coordinates of said SATPS receiver at a second location of said mobile unit; and

computing the heading of said SATPS receiver by utilizing said first set of three dimensional coordinates measurements and said second set of three dimensional coordinates measurements.

18. The method of claim 16, wherein said step of determining the relationship between tilt coordinates and the heading of said mobile unit further comprises the step of:

determining the heading of said SATPS receiver by utilizing a compass.

19. A method for generating a map, said method comprising the steps of:

performing three dimensional coordinates measurements of a mobile unit by using a satellite positioning system (SATPS) receiver mounted in a housing means of said mobile unit;

performing tilt coordinates measurements of said mobile unit synchronously with said three dimensional coordinates measurements of said mobile unit by using a tilt angle measurement device integrated with said SATPS receiver;

calculating three dimensional coordinates of an implement mounted in said mobile unit by solving a set of geometrical equations including said three dimensional coordinates of said mobile unit, said tilt coordinates of said mobile unit, and a distance between said SATPS receiver and said implement by using a SATPS/tilt integrated navigational computer;

recording three dimensional coordinates of said implement by using a memory unit of said SATPS/tilt integrated navigational computer; and

generating a map of an actual area covered by said implement by using a map generating software.