Method of determining absolute position for a motor vehicle

• US 8,521,412 B2
• Filed: 03/26/2010
• Issued: 08/27/2013
• Est. Priority Date: 03/26/2010
• Status: Active Grant

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Miucic, Radovan
• Primary Examiner(s): MANCHO, RONNIE M
• Application Number:
  US12/732,347
• Publication Number:
  US 20110238306A1
• Time in Patent Office: 1,250 Days
• Field of Search: 701/300, 701/301, 701/36, 701/412
• US Class Current: 701/300
• CPC Class Codes: G01C 21/28 with correlation of data from several navigational instruments
• CPC Class Codes: G01S 19/24 Acquisition or tracking or demodulation of signals transmitted by the system synchronisation aspects of direct sequence spread spectrum modulation H04B1/7073
• CPC Class Codes: G01S 19/396 Determining accuracy or reliability of position or pseudorange measurements
• CPC Class Codes: G01S 19/46 the supplementary measurement being of a radio-wave signal type
• CPC Class Codes: G01S 5/0072 Transmission between mobile stations, e.g. anti-collision systems
• CPC Class Codes: G01S 5/0284 Relative positioning
• CPC Class Codes: G01S 7/003 Transmission of data between radar, sonar or lidar systems and remote stations

Abstract

A method of determining an absolute position for a motor vehicle is disclosed. The method includes steps of receiving information related to the absolute positions of one or more remote sources. The method further includes steps of determining distances to the one or more remote sources. Methods for selecting a subset of remote sources from a set of all available remote sources to be used in determining an absolute position for the motor vehicle are also disclosed.

Claims

1. A method of determining an absolute position for a motor vehicle including an electronic control unit, the electronic control unit being configured to perform the method comprising the steps of:

receiving signals via a communication system, the signals containing information from a plurality of remote sources within a communication range of the communication system, the information including an absolute position for each remote source;

selecting a set of remote sources of the plurality of remote sources that are in line of sight of the motor vehicle;

excluding any remote sources of the plurality of remote sources that are not in line of sight of the motor vehicle;

determining a distance to each remote source in the set of remote sources;

selecting a subset of remote sources from the set of remote sources that are spread approximately evenly around the motor vehicle; and

calculating the absolute position of the motor vehicle using the absolute position of each remote source in the subset of remote sources and using the distance to each remote source in the subset of remote sources.

2. The method according to claim 1, wherein the distance to each remote source is determined using information related to a received signal strength index.

3. The method according to claim 2, wherein the distance to each remote source is determined using historical received signal strength index information.

4. The method according to claim 1, wherein the motor vehicle is configured to receive absolute position information from at least four remote sources.

5. The method according to claim 4, wherein the motor vehicle is configured to determine distances between the motor vehicle and each of the at least four remote sources using information related to a received signal strength index.

6. The method according to claim 5, wherein the absolute positions of the at least four remote sources and the distances to the at least four remote sources are used to calculate the absolute position of the motor vehicle.

7. The method according to claim 1, wherein at least one of the remote sources in the subset of remote sources is a remote vehicle.

8. The method according to claim 1, wherein at least one of the remote sources in the subset of remote sources is a roadside unit.

9. The method according to claim 1, wherein at least one of the remote sources in the subset of remote sources is a satellite.

10. The method according to claim 1, wherein the step of selecting the subset of remote sources further includes the steps of:

selecting a first remote source from the set of remote vehicles, the first remote source being closest to the motor vehicle; and

selecting a second remote source from the set of remote sources, the second remote source being disposed in a direction approximately opposite of a direction of the first remote source with respect to the motor vehicle.

11. The method according to claim 10, wherein the method further includes a step of selecting a third remote source that is disposed in a direction approximately between the direction of the first remote source and the direction of the second remote source.

12. The method according to claim 11, wherein the method further includes a step of selecting a fourth remote vehicle that is disposed in an approximately opposite direction from the third remote source.

13. The method according to claim 1, wherein the absolute position of the motor vehicle is a GPS position.

14. A method of determining an absolute position for a motor vehicle including an electronic control unit, the electronic control unit being configured to perform the method comprising the steps of:

receiving information from a plurality of remote sources, the information including an absolute position for each remote source;

selecting a set of remote sources of the plurality of remote sources that are in line of sight of the motor vehicle, the set of remote sources including at least three remote sources;

excluding any remote sources of the plurality of remote sources that are not in line of sight of the motor vehicle;

determining a distance to each remote source in the set of remote sources;

calculating a first absolute position for the motor vehicle using the set of remote sources with a first remote source excluded;

calculating a second absolute position for the motor vehicle using the set of remote sources with a second remote source excluded;

calculating a third absolute position for the motor vehicle using the set of remote sources with a third remote source excluded;

comparing the solutions associated with the calculation of the first absolute position, the calculation of the second absolute position, and the calculation of the third absolute position to detect a divergent solution;

identifying one or more remote sources with bad absolute positions from the set of remote sources used to calculate the divergent solution; and

recalculating the absolute position of the motor vehicle using the set of remote sources that excludes the one or more remote sources with bad absolute positions.

15. The method according to claim 14, wherein the method includes a step of determining the number of remote sources in the set of remote sources.

16. The method according to claim 15, wherein the method includes:

selecting a subset of remote sources from the set of remote sources that are spread approximately evenly around the motor vehicle; and

calculating the absolute position of the motor vehicle using the absolute position of each remote source in the subset of remote sources and using the distance to each remote source in the subset of remote sources.

17. The method according to claim 14, wherein the method includes the further steps of:

determining that the set of remote sources includes N remote sources;

calculating a plurality of absolute positions for the motor vehicle using information received from a plurality of different groups of remote sources, each group comprising N−

1 remote sources;

comparing the solutions associated with the calculations of the plurality of absolute positions for the motor vehicle corresponding to each group to detect a divergent solution;

identifying one or more remote sources with bad absolute positions from the set of remote sources used to calculate the divergent solution; and

recalculating the absolute position of the motor vehicle using the set of remote sources that excludes the one or more remote sources with bad absolute positions.

18. The method according to claim 17, wherein the method includes a step of removing remote sources associated with incorrectly estimated distances between the motor vehicle and the remote sources.

19. The method according to claim 14, wherein the set of remote sources includes at least one remote vehicle and at least one roadside unit.

20. The method according to claim 14, wherein the set of remote sources includes at least four remote vehicles.

21. The method according to claim 14, wherein the distance is an estimated distance.

22. The method according to claim 14, wherein the set of remote sources includes at least one remote vehicle and at least one satellite.

23. The method according to claim 14, wherein the set of remote sources includes at least one roadside unit and at least one satellite.

24. The method according to claim 14, wherein the set of remote sources includes at least one roadside unit, at least one remote vehicle, and at least one satellite.