GNSS vehicle location involving overlapping roads

• US 10,234,568 B2
• Filed: 05/12/2016
• Issued: 03/19/2019
• Est. Priority Date: 05/12/2016
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Croyle, Steven R.
• Primary Examiner(s): Lin, Abby Y
• Assistant Examiner(s): Malhotra, Sanjeev
• Application Number:
  US15/152,856
• Publication Number:
  US 20170329019A1
• Time in Patent Office: 1,041 Days
• Field of Search: 701 1, 701 22, 701 37, 701 93, 701118, 701301, 701409, 701428, 701450, 701454, 701532, 701533, 701 41, 701472, 701 25, 701 314, 701117, 701423, 701445, 701469, 701470, 705 4, 705 725, 705 13, 705 1, 34235726, 342 36, 34235723, 34235733, 34235739, 34235761, 702141, 702142, 702152, 455418, 4554561, 340953, 340961, 404 1
• CPC Class Codes: G01C 21/165 combined with non-inertial navigation instruments
• CPC Class Codes: G01C 21/30 Map- or contour-matching
• CPC Class Codes: G01C 21/3667 Display of a road map G01C21/3614 takes precedence; guidance using 3D or perspective road maps G01C21/3635
• CPC Class Codes: G01S 19/47 the supplementary measurement being an inertial measurement, e.g. tightly coupled inertial
• 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
• CPC Class Codes: G01S 19/52 Determining velocity

Abstract

A system and method of determining a vehicle location where roads have different elevations and at least partially overlap. The method carried out by the system includes: receiving a plurality of Global Navigation Satellite System (GNSS) satellite signals at a vehicle; determining a vehicle location and a vehicle velocity including an up velocity based on the received GNSS signals; identifying a plurality of roads, within a range of the vehicle location, at least one of which has a different elevation than the other road(s); and selecting at least one of the plurality of roads within the range based on the up velocity component.

Claims

1. A method of determining a location of a vehicle using a Global Navigation Satellite System (GNSS) installed in the vehicle, wherein the vehicle location involves roads having different elevations that at least partially overlap, comprising the steps of:

(a) receiving a plurality of GNSS satellite signals at a GNSS receiver installed in the vehicle;

(b) using the GNSS receiver, determining the location of the vehicle in a two-dimensional plane, wherein the location includes latitude and longitude coordinates based on the received GNSS signals;

(c) selecting one or more maps from a map database based on the latitude and longitude coordinates;

(d) using the GNSS receiver, generating a three-dimensional velocity vector of the vehicle based on the received GNSS signals, wherein the three-dimensional velocity vector includes an up velocity component;

(e) detecting a change in vehicle elevation based on a value of the up velocity component;

(f) in identifying from the maps selected in step (c) a plurality of roads, within a range of the vehicle location, at least one of which has a different elevation than the other road(s) and at least partially overlaps with at least one of the other road(s) in the two-dimensional plane at common latitude and longitude coordinates;

(g) determining a slope of the vehicle travel by calculating a three-dimensional displacement vector of the vehicle based on the three-dimensional velocity vector;

(h) determining which of the identified plurality of roads having common latitude and longitude coordinates the vehicle is traveling by comparing the slope of the vehicle calculated in step (e) to a slope for each of the plurality of roads identified in step (f);

(i) setting a vehicle position in the vehicle GNSS based on the comparison in step (h); and

(j) providing navigational services to a vehicle occupant based on the vehicle position set in step (i).

2. The method of claim 1, wherein the vehicle location is a three-dimensional vehicle location.

3. The method of claim 1, wherein the plurality of roads are selected based on one or more ramps within the range of the vehicle location.

4. The method of claim 1, further comprising the step of determining whether the up velocity component is non-zero.

5. The method of claim 3, further comprising the step of comparing the slope of vehicle travel with one or more ramp slopes obtained from the map database.

6. The method of claim 1, wherein the determined vehicle location further comprises a height component.

7. The method of claim 1, further comprising the step of calibrating an accelerometer based on the up velocity component.

8. A vehicle comprising:

a Global Navigation Satellite System (GNSS) including a GNSS receiver configured to receive a plurality of GNSS satellite signals with respect to the vehicle and to determine, based on the received GNSS signals, a location and a velocity of the vehicle, wherein the location includes latitude and longitude coordinates in a two-dimensional plane, and the velocity is a three-dimensional velocity vector having an up velocity component; and

a microprocessor configured to;

receive the vehicle location and the up velocity component, and by accessing a map matching module, identify a plurality of roads within a range of the vehicle location, at least one of which has a different elevation than the other road(s) and at least partially overlaps with at least one of the other road(s) in the two-dimensional plane at common latitude and longitude coordinates;

detect a change in vehicle elevation based on a value of the up velocity component;

determine a slope of the vehicle travel by calculating a three-dimensional displacement vector of the vehicle based on the three-dimensional velocity vector;

determine which of the identified plurality of roads having common latitude and longitude coordinates the vehicle is traveling by comparing the slope of the vehicle to a slope for each of the identified plurality of roads;

set a vehicle position in the vehicle GNSS based on the slope comparison; and

provide navigational services to a vehicle occupant based on the set vehicle position.

9. The vehicle of claim 8 further comprising an accelerometer having a bias value that is calibrated based on the up velocity component.