AUTONOMOUS VEHICLE POSITIONING SYSTEM FOR MISBEHAVIOR DETECTION

• US 20130297195A1
• Filed: 06/19/2012
• Published: 11/07/2013
• Est. Priority Date: 05/03/2012
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Das, Sushanta, Saha, Mounita
• Granted Patent: US 8,954,261 B2
• Time in Patent Office: Days
• US Class Current: 701/117
• CPC Class Codes: G01C 21/3697 Output of additional, non-guidance related information, e.g. low fuel level G01C21/3679 takes precedence
• CPC Class Codes: G08G 1/163 involving continuous checking

Abstract

An autonomous vehicle positioning system for determining a position of a remote vehicle relative to a mobile host vehicle based on safety alert messages broadcast from the remote vehicle relating to an event in a road of travel. A host vehicle communication unit communicates with the remote vehicle for receiving the broadcast messages from the remote vehicle. A host vehicle control unit identifies reference points along the road of travel. Each reference point identifies a position of the host vehicle and associated signal reception properties, for example time-of-arrival, angle-of-arrival and received signal strength when the host vehicle receives the broadcast message. The control unit of the host vehicle selects a set of the reference points having identified positions and associated times, angles and signal strength. The control unit determines a position of the remote vehicle as a function of the time difference-of-arrival, angle-of-arrival or received signal strength between each selected reference point in the set.

Claims

1. An autonomous vehicle positioning system for determining a position of a remote vehicle relative to a mobile host vehicle based on safety alert messages broadcast from the remote vehicle relating to an event in a road of travel, the system comprising:

a host vehicle communication unit communicating with the remote vehicle for receiving the broadcast messages from the remote vehicle;

a host vehicle control unit for identifying reference points along the road of travel, each reference point identifying a position of the host vehicle and a signal reception property when the host vehicle receives the broadcast message; and

wherein the control unit of the host vehicle selects a set of the reference points having identified positions and associated signal reception properties, wherein the control unit utilizes the signal reception properties at each reference point associated with a received broadcast message, and wherein the control unit determines a position of the remote vehicle as a function of the signal reception properties at each selected reference point in the set.

2. The system of claim 1 wherein the signal reception property includes an angle-of-arrival of the broadcast message, wherein each reference point identifies a position of the host vehicle, an angle-of-arrival of the broadcast message, and an associated line-of-bearing when the host vehicle receives the broadcast message, wherein the control unit of the host vehicle selects a set of the reference points having identified positions, associated angles-of-arrival, and associated lines-of-bearing, wherein the control unit determines a point of intersection between two respective lines-of-bearing corresponding to two reference points associated with received broadcast messages, and wherein the control unit determines a position of the remote vehicle as the intersection point between two lines-of-bearing.

3. The system of claim 1 wherein the signal reception property includes a time-of-arrival of the broadcast message, wherein each reference point identifies a position of the host vehicle and an associated time-of-arrival when the host vehicle receives the broadcast message, wherein the control unit of the host vehicle selects a set of the reference points having identified positions and associated times, wherein the control unit determines a time difference-of-arrival between each reference point associated with a received broadcast message, and wherein the control unit determines a position of the remote vehicle as a function of the time difference-of-arrival between each selected reference point in the set.

4. The system of claim 3 wherein the control unit selects a next set of reference points for determining a position of the remote vehicle based on a time difference-of-arrival between each received broadcast message of the next set of reference points, wherein the control unit determines a position of the remote vehicle as a function of the time difference-of-arrival between each reference point of the next set of selected reference points, wherein the control unit compares the position of the remote vehicle as determined by the first set of reference points with the position as determined by the next set of reference points, and wherein the control unit determines misbehavior by the remote vehicle if the distance between determined positions is greater than a predetermined distance threshold.

5. The system of claim 3 wherein a next reference point is selected by the control unit, wherein the location and time of arrival for the next reference point are identified, wherein the control unit determines an expected time-of-arrival of the broadcast message at the next reference point position of the host vehicle, and wherein the control unit determines a difference between the identified time-of-arrival of the broadcast message at the next reference point of the host vehicle and the actual time-of-arrival of the broadcast message at the next reference point of the host vehicle, and wherein the control unit determines a misbehavior by the remote vehicle if the difference between the identified time-of-arrival and the expected time-of-arrival is greater than a predetermined threshold.

6. The system of claim 5 wherein the control unit identifies additional reference points and associated times-of arrival, and wherein misbehavior by the remote vehicle is determined if the difference between the identified time-of-arrival and the expected time-of-arrival of any one of the additional reference points is greater than the predetermined threshold.

7. The system of claim 1 wherein a received signal strength indicator is determined for each message received by the host vehicle, wherein the control unit selects each of the respective reference points based on a value of the received signal strength indicator.

8. The system of claim 7 wherein the control unit selects each of the respective reference points based on the value of the received signal strength indicator being above predetermined signal strength.

9. The system of claim 7 wherein the control unit prioritizes the broadcast messages based on the values of the received signal strength indicators, wherein the control unit selects each of the respective reference points based on the reference points having a highest value of signal strength indicator among the identified reference points along the road of travel.

10. The system of claim 1 wherein the vehicle communication system is a vehicle-to-vehicle communication system.

11. The system of claim 10 wherein the vehicle-to-vehicle communication system is a dedicated short range communication system.

12. The system of claim 1 wherein the set of reference points includes at least three reference points.

13. The system of claim 1 wherein the next set of reference points includes at least three reference points.

14. The system of claim 1 wherein the remote vehicle broadcasting unit broadcasts safety alert messages at timed intervals.

15. The system of claim 14 wherein the remote vehicle broadcasting unit broadcasts messages at ten times per second.

16. The system of claim 1 wherein the safety alert message is a post crash notification message.

17. A method for determining a position of a remote vehicle relative to a mobile host vehicle based on safety alert messages broadcast from the remote vehicle relating to an event in a road of travel, the method comprising the steps of:

the host vehicle receiving broadcast messages from a remote vehicle, the broadcast message relating to a safety related event in the road of travel;

the host vehicle control unit identifying reference points along the road of travel, each reference point identifying a position of the host vehicle and an associated time-of-arrival when the host vehicle receives the broadcast message;

the control unit selecting a set of the reference points having identified positions and associated times; and

the control unit determining a time difference-of-arrival between each reference point associated with a received broadcast message, wherein the control unit determines a position of the remote vehicle as a function of the time difference-of-arrival between each selected reference points in the set.

18. The method of claim 17 further comprising the steps of:

the control unit selecting a next set of reference points for determining a position of the remote vehicle based on a time difference-of-arrival between each received broadcast message of the next set of reference points;

determining a position of the remote vehicle as a function of the time difference-of-arrival between each reference point of the next set of selected reference points;

comparing the position of the remote vehicle as determined by the first set of reference points with the position as determined by the next set of reference points; and

the control unit determining misbehavior of the remote vehicle if the distance between determined positions is greater than a predetermined distance threshold.

19. The method of claim 17 wherein a next reference point is selected by the control unit, wherein the location and time of arrival for the next reference point are identified, wherein the control unit determines an expected time-of-arrival of the broadcast message at the next reference point position of the host vehicle, and wherein the control unit determines a difference between the identified time-of-arrival of the broadcast message at the next reference point of the host vehicle and the actual time-of-arrival of the broadcast message at the next reference point of the host vehicle, and wherein the control unit determines a misbehavior of the remote vehicle if the difference between the identified time-of-arrival and the expected time-of-arrival is greater than a predetermined threshold.

20. The system of claim 19 wherein additional reference points and associated times-of arrival are identified by the control unit, and wherein misbehavior of the remote vehicle is determined if the difference between the identified time-of-arrival and the expected time-of-arrival of any one of the additional reference points is greater than the predetermined threshold.

21. The method of claim 17 wherein a received signal strength indicator is determined for each message received by the host vehicle, wherein the control unit selects each of the respective reference points based on a value of the received signal strength indicator.

22. A method for determining a position of a remote vehicle relative to a mobile host vehicle based on safety alert messages broadcast from the remote vehicle relating to an event in a road of travel, the method comprising the steps of:

the host vehicle receiving broadcast messages from a remote vehicle, the broadcast message relating to a safety related event in the road of travel;

the host vehicle control unit identifying reference points along the road of travel, each reference point identifying a position of the host vehicle and an associated angle-of-arrival when the host vehicle receives the broadcast message;

the control unit selecting a set of reference points having identified positions; and

the control unit determining an angle-of-arrival and line-of-bearing at each reference point associated with a received broadcast message, wherein the control unit determines a position of the remote vehicle as a function of an intersection between at least two lines-of-bearing.

23. The method of claim 22 wherein the control unit identifies a position of the host vehicle, an angle-of-arrival of the broadcast message, and an associated line-of-bearing for each reference point when the host vehicle receives the broadcast message, wherein the control unit of the host vehicle selects a set of the reference points having identified positions, associated angles-of-arrival, and associated lines-of-bearing, wherein the control unit determines a point of intersection between two respective lines-of-bearing corresponding to two reference points associated with received broadcast messages, and wherein the control unit determines a position of the remote vehicle as the intersection point between two lines-of-bearing.

24. The method of claim 22 wherein a next reference point is selected by the control unit, wherein the control unit identifies a position of the host vehicle, an angle-of-arrival of the broadcast message, and an associated line-of-bearing when the host vehicle receives the broadcast message at the next reference point, wherein the control unit determines whether the line-of-bearing for the next reference point intersects the intersection point determined by the set of reference points for evaluating a reliability of the position of the remote vehicle.