Accurate vehicle navigation

• US 6,230,097 B1
• Filed: 08/31/1998
• Issued: 05/08/2001
• Est. Priority Date: 08/31/1998
• Status: Expired due to Term

• Current Assignee: Trimble Navigation Limited (Trimble Inc.)
• Original Assignee: Trimble Navigation Limited (Trimble Inc.)
• Inventors: Janky, James M., Dance, Scott
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): Beaulieu, Yonel
• Application Number:
  US09/144,397
• Time in Patent Office: 981 Days
• Field of Search: 701/207, 701/211, 701/215, 701/23, 701/200, 701/24, 342/357.01, 342/357.02, 342/357.06, 342/357.08, 340/901, 340/988, 340/991, 340/435
• US Class Current: 701/207
• CPC Class Codes: G01C 21/26 specially adapted for navigation in a road network
• CPC Class Codes: G08G 1/167 Driving aids for lane monitoring, lane changing, e.g. blind spot detection

Abstract

Method and system for accurate vehicle navigation and tracking within a selected lane on a roadway or a waterway. A location determination (LD) receiver, carried on the vehicle, receives LD signals from satellite-based LD signal sources, receives LD signal correction information from one or more other wide area LD correction sources, estimates a corrected vehicle location (good to within 10-50 cm) and velocity (optional) relative to one or more lane boundaries that define the selected lane, and displays vehicle location and velocity within the lane. When the vehicle approaches a lane boundary too quickly, or is too close to the lane boundary, an alarm signal or other control mechanism can be activated. The LD correction information is delivered to the LD receiver via a channel of suitable bandwidth. The system can also be used to map and store lane boundary coordinates for selected segments of a roadway or waterway.

Claims

1. A method for vehicle navigation on a selected lane on a vehicle path, the method comprising the steps of:

obtaining coordinates for a boundary line segment that helps define said selected lane on a selected path on which a vehicle travels;

receiving location determination (LD) signals and LD correction signals that allow estimation and correction of the present location of the vehicle, relative to the selected lane, with an inaccuracy that is no more than about 50 cm, where the LD correction signals are provided by at least three spaced apart LD correction signal sources, with at least two of the LD correction signals being produced by LD correction signal sources that are at least a selected distance d from the vehicle, where d is at least 50 km, said step of receiving location determination (LD) signals and LD correction signals further comprising

receiving said LD correction signals as part of a composite signal that also contains at least one signal that is unrelated to said LD correction signals and to said LD signals; and

separating said LD correction signals from the at least one signal that is unrelated to said LD correction signals and to said LD signals; and

determining and displaying, in at least one of graphical form and alphanumeric form, the present location of the vehicle relative to the boundary line segment.

2. The method of claim 1, further comprising the step of selecting said distance d to be at least 100 km.

3. The method of claim 1, further comprising the step of selecting said distance d to be at least 500 km.

4. The method of claim 1, further comprising the step of selecting said distance d to be at least 1000 km.

5. The method of claim 1, further comprising the step of determining a velocity in a selected direction with which said vehicle approaches at said boundary line segment for said selected lane.

6. The method of claim 5, further comprising the step of providing an audible or visual alarm signal if said velocity with which said vehicle approaches said boundary line segment exceeds a selected threshold velocity value.

7. The method of claim 5, further comprising the step of displaying, in at least one of graphical form and alphanumeric form, said velocity with which said vehicle approaches said boundary line segment.

8. The method of claim 1, further comprising the step of providing an audible or visual alarm if said vehicle is closer than a selected threshold separation distance from said boundary line segment.

9. The method of claim 1, further comprising the step of selecting said vehicle path to be a roadway and selecting said vehicle to be a land vehicle.

10. The method of claim 1, further comprising the step of selecting said vehicle path to be a waterway and selecting said vehicle to be a water vehicle.

11. The method of claim 1, wherein said step of obtaining said coordinates for said boundary line segment comprises the step of receiving said coordinates from a roadway information database that is spaced apart from said vehicle.

12. The method of claim 1, wherein said step of obtaining said coordinates for said boundary line segment comprises the step of receiving said coordinates from a roadway information database that is on said vehicle.

13. The method of claim 1, wherein said step of receiving said LD corrections signals comprises receiving said LD correction signals from a communications system drawn from a group of communications systems consisting of Satellite Digital Audio Radio Service, FM subcarrier service, Sky Station and Private Radio.

14. A system for vehicle navigation on a selected lane on a selected path, the system comprising a computer that is programmed to:

obtain coordinates for a least one boundary line segment that helps define said selected lane on a path on which a vehicle travels;

receive location determination (LD) signals and LD correction signals that allow estimation of the present location of the vehicle, relative to the selected lane with an inaccuracy that is no more than about 50 cm, with at least two of the LD correction signals being produced by LD correction signal sources that are at least a selected distance d from the vehicle, where d is at least 50 km;

determine and display, in at least one of graphical form and alphanumeric form, the present location of the vehicle relative to the boundary line segment;

receive said LD correction signals as part of a composite signal that also contains at least one signal that is unrelated to said LD correction signals and to said LD signals; and

separate said LD correction signals from the at least one signal that is unrelated to said LD correction signals and to said LD signals.

15. The system of claim 14, wherein said selected distance d is at least 100 km.

16. The system of claim 14, wherein said selected distance d is at least 500 km.

17. The system of claim 14, wherein said selected distance d is at least 1000 km.

18. The system of claim 14, wherein said computer is further programmed to determine a velocity in a selected direction with which said vehicle approaches said boundary line segment for said selected lane.

19. The system of claim 18, wherein said computer is further programmed to provide an alarm signal if said velocity with which said vehicle approaches said boundary line segment exceeds a selected threshold velocity value.

20. The system of claim 14, wherein said computer is further programmed to display, in at least one of graphical form and alphanumeric form, said velocity with which said vehicle approaches said at least one of said boundary line segments.

21. The system of claim 14, wherein said computer is further programmed to provide an audible or visual alarm if said vehicle is closer than a selected threshold separation distance from said boundary line segment.

22. The system of claim 14, wherein said vehicle path is a roadway and said vehicle is a land vehicle.

23. The system of claim 14, wherein said vehicle path is a waterway and said vehicle is a water vehicle.

24. The system of claim 14, wherein said computer is further programmed to receive said coordinates for said boundary line segment from a roadway information database that is spaced apart from said vehicle.

25. The system of claim 14, wherein said computer is further programmed to obtain said coordinates for said boundary line segment from a roadway information database that is on said vehicle.

26. The system of claim 14, wherein said LD correction signals are received from a communications system drawn from a group of systems consisting of Satellite Digital Audio Radio Service, FM subcarrier service, Sky Station and Private Radio.