System and method for determining position and distance of objects using road fiducials

• US 9,646,497 B1
• Filed: 10/30/2015
• Issued: 05/09/2017
• Est. Priority Date: 01/16/2013
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Google Inc. (Alphabet Inc.)
• Inventors: Chatham, Andrew Hughes
• Primary Examiner(s): MARC-COLEMAN, MARTHE Y
• Application Number:
  US14/928,444
• Time in Patent Office: 557 Days
• Field of Search: 701 28, 701466, 340933, 340937, 340903, 340435, 340437
• CPC Class Codes: B60W 2420/403 Image sensing, e.g. optical camera
• CPC Class Codes: B60W 2420/408 Radar; Laser, e.g. lidar
• CPC Class Codes: B60W 2552/53 Road markings, e.g. lane marker or crosswalk
• CPC Class Codes: B60W 2554/4026 Cycles
• CPC Class Codes: B60W 2554/4029 Pedestrians
• CPC Class Codes: B60W 2554/4041 Position
• CPC Class Codes: B60W 2556/50 of positioning data, e.g. GPS [Global Positioning System] data
• CPC Class Codes: B60W 30/00 Purposes of road vehicle drive control systems not related to the control of a particular sub-unit, e.g. of systems using conjoint control of vehicle sub-units
• CPC Class Codes: B60W 30/08 Active safety systems predicting or avoiding probable or impending collision or attempting to minimise its consequences
• CPC Class Codes: B60W 30/12 Lane keeping
• CPC Class Codes: B60W 60/0027 using trajectory prediction for other traffic participants
• CPC Class Codes: G05D 1/0234 using optical markers or beacons optical beacons per se G01S1/70
• CPC Class Codes: G05D 1/0246 using a video camera in combination with image processing means
• CPC Class Codes: G06V 20/588 Recognition of the road, e.g. of lane markings; Recognition of the vehicle driving pattern in relation to the road
• CPC Class Codes: G08G 1/00 Traffic control systems for road vehicles arrangement of road signs or traffic signals E01F9/00 ; automatic vehicle control B62D
• CPC Class Codes: G08G 1/166 for active traffic, e.g. moving vehicles, pedestrians, bikes
• CPC Class Codes: G08G 1/167 Driving aids for lane monitoring, lane changing, e.g. blind spot detection

Abstract

Aspects of the invention relate generally to autonomous vehicles. The features described improve the safety, use, driver experience, and performance of these vehicles by using ground markers to determine the position of the surrounding objects. In particular, the autonomous vehicle is capable of detecting nearby objects, such as vehicles and pedestrians, and is able to determine the position of these objects based on whether they have passed over ground markers.

Claims

1. A method, comprising:

detecting, using a camera a set of ground markers positioned on a surface of a roadway so that each given ground marker of the set of ground markers is in a position that allows an object to at least partially obscure the given ground marker when the object traverses over the given ground marker on the surface of the roadway;

for each detected ground marker of the set of ground markers, recording, using one or more processors, the position of the detected ground marker; and

using the recorded position of the detected ground marker to update a database of ground marker positions that identifies positions and appearances of ground markers to allow a vehicle having the updated database to detect the proximity of another object to the vehicle based on the another object passing over one of the ground markers of the set of ground markers.

2. The method of claim 1, wherein the position of each given ground marker corresponds to a center region of a lane of the roadway.

3. The method of claim 1, wherein the set of ground markers are positioned at regular intervals.

4. The method of claim 1, wherein the set of ground markers are positioned at irregular intervals.

5. The method of claim 1, wherein at least two of the ground markers of the set of ground markers have different shape and are detected directly adjacent to one another on the surface of the roadway, and the updated database of ground marker positions further identifies a shape of each ground marker of the set of ground markers.

6. The method of claim 1, wherein at least two ground markers are detected directly adjacent to one another on the surface of the roadway at different orientations, and the updated database of ground marker positions further identifies an orientation of each ground marker of the set of ground markers.

7. The method of claim 1, wherein the position of the given ground marker allows the ground marker to be visible to the camera mounted on the vehicle as the vehicle moves along the roadway and approaches the ground marker.

8. The method of claim 1, further comprising providing the updated database of ground marker positions to a vehicle having an autonomous driving mode.

9. A system comprising:

a set of ground markers positioned on a surface of a roadway so that each given ground marker of the set of ground markers is in a position that allows an object to at least partially obscure the given ground marker when the object traverses over the ground marker on the surface of the roadway;

a camera configured to detect the set of ground markers;

a memory configured to store positions of the detected set of ground markers; and

a processor in communication with the camera and the memory, the processor being operable to update a database of ground marker positions that identifies positions and appearances of ground markers to allow a vehicle having the updated database to detect the proximity of another object to the vehicle based on the another object passing over one of the ground markers of the set of ground markers.

10. The system of claim 9, wherein the position of each given ground marker corresponds to a center region of a lane of the roadway.

11. The system of claim 9, wherein the set of ground markers is positioned at regular intervals.

12. The system of claim 9, wherein the set of ground markers are positioned at irregular intervals.

13. The system of claim 9, wherein at least two of the ground markers of the set of ground markers have different shapes, and the at least two of the ground markers are placed directly adjacent to one another on the surface of the roadway, and the database of ground marker positions further identifies a shape of each ground marker of the set of ground markers.

14. The system of claim 9, wherein at least two ground markers are positioned directly adjacent to one another on the surface of the roadway at different orientations, and the database of ground marker positions further identifies an orientation of each ground marker of the set of ground markers.

15. The system of claim 9, wherein the position of the given ground marker allows the ground marker to be visible to the camera mounted on the vehicle as the vehicle moves along the roadway and approaches the ground marker.

16. The system of claim 9, further comprising providing the updated database of ground marker positions to a vehicle having an autonomous driving mode.

17. A non-transitory recording medium on which instructions are stored, the instructions, when executed by one or more processors, cause the one or more processors to perform a method, the method comprising:

recording positions of a set of ground markers on a surface of a roadway, where the position of each given ground marker of the set of ground markers allows an object to at least partially obscure the given ground marker when the object traverses over the given ground marker on the surface of the roadway;

using the recorded position of the placed ground marker to update a database of ground marker positions that identifies positions and appearances of ground markers; and

providing the updated database of ground marker positions to a vehicle having an autonomous driving mode to allow the vehicle to detect the proximity of another object to the vehicle based on the another object passing over one of the ground markers of the set of ground markers.

18. The medium of claim 17, wherein at least two of the ground markers of the set of ground markers have different shapes, and the at least two of the ground markers have positions that are directly adjacent to one another on the surface of the roadway, and the database of ground marker positions further identifies a shape of each ground marker of the set of ground markers.

19. The medium of claim 17, wherein at least two ground markers have positions that are directly adjacent to one another on the surface of the roadway at different orientations, and the database of ground marker positions further identifies an orientation of each ground marker of the set of ground markers.

20. The medium of claim 17, wherein the position of each given ground marker corresponds to a center region of a lane of the roadway.