Method and device for improving GPS-based positioning of vehicles on roads

• US 20050283312A1
• Filed: 06/16/2004
• Published: 12/22/2005
• Est. Priority Date: 06/16/2004
• Status: Abandoned Application

• Current Assignee: Daimler AG (Mercedes-Benz Group AG)
• Original Assignee: Daimler Chrysler Company LLC (Stellantis NV)
• Inventors: Taliwal, Vikas
• Application Number:
  US10/869,188
• Publication Number:
  US 20050283312A1
• Time in Patent Office: Days
• US Class Current: 701/214
• CPC Class Codes: G01S 19/41 Differential correction, e.g. DGPS [differential GPS]
• CPC Class Codes: G01S 19/50 whereby the position solution is constrained to lie upon a particular curve or surface, e.g. for locomotives on railway tracks

Abstract

A method for estimating an error in GPS signals used by a vehicle estimates an error in the GPS signals received by the vehicle as a function of a difference in a geometry of the GPS signals related to a curved section of the road and a geometry of the curved section of the road. A device and vehicle for utilizing the method are also provided.

Claims

1. A method for estimating an error in GPS signals used by a vehicle comprising the step of:

estimating an error in the GPS signals received by the vehicle as a function of a difference in a geometry of the GPS signals related to a curved section of the road and a geometry of the curved section of the road.

2. The method as recited in claim 1 wherein the geometry of the curved section of the road is determined at the location of the GPS signals.

3. The method as recited in claim 1 further comprising correcting the GPS signals during a straight section of the road following the curved section of the road as a function of the error estimated on the curved section of the road.

4. The method as recited in claim 3 further comprising re-estimating the error in a further curved section following the straight section.

5. The method as recited in claim 1 wherein a magnitude of the error is estimated using the following equations:

Δ

x=Rg cos hg−

Rr cos hr; and

Δ

y=Rg sin hg−

Rr sin hr, where Rg is a radius of curvature of the GPS signals, Rr is a radius of curvature of the road at a location of the GPS signals, hg is a heading of the GPS signals, and hr is a road heading at a location of the GPS signals.

6. The method as recited in claim 1 further comprising determining if the vehicle is traveling in a clockwise or counterclockwise direction in the curved section.

7. The method as recited in claim 1 wherein the geometry of the GPS signals is a determined from at least three GPS signal points.

8. The method as recited in claim 1 wherein the geometry of the curved section of the road is determined from digital road map information.

9. A device for measuring GPS signal errors for a vehicle, the device comprising:

a GPS device;

a processor for determining a curved section of a road; and

a memory for storing a digital road map, the processor estimating an error in the GPS signals received by the vehicle as a function of a difference in a geometry of the GPS signals related to the curved section of the road and a geometry of the curved section of the road.

10. The device as recited in claim 9 wherein the GPS device is a non-differential GPS device.

11. A vehicle comprising:

a GPS device;

a processor for determining a curved section of a road; and

a memory for storing a digital road map, the processor estimating an error in the GPS signals received by the vehicle as a function of a difference in a geometry of the GPS signals related to the curved section of the road and a geometry of the curved section of the road.

12. A method for estimating an error in GPS signals used by a vehicle comprising the step of:

estimating an error in the GPS signals received by the vehicle as a function of a vehicle heading at a GPS signal point and a road heading at the GPS signal point in a curved section of a road.

13. The method as recited in claim 12 wherein the error is estimated as a function of a GPS radius of curvature and a road radius of curvature at the GPS signal point.

14. A method for estimating an error in GPS signals used by a vehicle comprising the step of:

estimating an error in the GPS signals received by the vehicle a function of a GPS radius of curvature and a road radius of curvature at a GPS signal point in a curved section of a road.