Detecting and responding to tailgaters

• US 9,671,784 B1
• Filed: 02/05/2016
• Issued: 06/06/2017
• Est. Priority Date: 07/24/2013
• Status: Active Grant

• Current Assignee: Waymo LLC (Alphabet Inc.)
• Original Assignee: Waymo LLC (Alphabet Inc.)
• Inventors: Nemec, Philip, Dolgov, Dmitri A., Aula, Anne Kristiina
• Primary Examiner(s): Marc, Mcdieunel
• Application Number:
  US15/016,539
• Time in Patent Office: 487 Days
• Field of Search: 701 1, 701 93, 701 96, 701301, 701451, 340435, 340436, 340467, 340901, 340903, 340933, 34042616, 340427, 180167, 455500
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2554/80 Spatial relation or speed relative to objects
• CPC Class Codes: B60W 2554/801 Lateral distance
• CPC Class Codes: B60W 2554/802 Longitudinal distance
• CPC Class Codes: B60W 2754/30 Longitudinal distance
• CPC Class Codes: B60W 30/16 Control of distance between vehicles, e.g. keeping a distance to preceding vehicle
• CPC Class Codes: B60W 60/0016 of the vehicle or its occupants
• CPC Class Codes: B62D 15/025 Active steering aids, e.g. helping the driver by actively influencing the steering system after environment evaluation B62D1/28 takes precedence
• CPC Class Codes: B62D 15/0255 Automatic changing of lane, e.g. for passing another vehicle
• CPC Class Codes: G05D 1/00 Control of position, course, altitude or attitude of land, water, air or space vehicles, e.g. using automatic pilots drive control systems specially adapted for autonomous road vehicles B60W60/00
• CPC Class Codes: G05D 1/0055 with safety arrangements
• CPC Class Codes: G05D 1/0287 involving a plurality of land vehicles, e.g. fleet or convoy travelling traffic control systems for road vehicles G08G1/00, particularly anticollision systems G08G1/16

Abstract

An autonomous vehicle detects a tailgating vehicle and uses various response mechanisms. A vehicle is identified as a tailgater based on whether its characteristics meet a variable threshold. When the autonomous vehicle is traveling at slower speeds, the threshold is defined in distance. When the autonomous vehicle is traveling at faster speeds, the threshold is defined in time. The autonomous vehicle responds to the tailgater by modifying its driving behavior. In one example, the autonomous vehicle adjusts a headway buffer (defined in time) from another vehicle in front of the autonomous vehicle. In this regard, if the tailgater is T seconds too close to the autonomous vehicle, the autonomous vehicle increases the headway buffer to the vehicle in front of it by some amount relative to T.

Claims

1. A system for controlling aspects of a first vehicle, the system comprising one or more processors configured to:

receive sensor data from a sensor;

detect, using the sensor data, a second vehicle driving behind a first vehicle;

identify the second vehicle as a potential tailgater of the first vehicle when the second vehicle meets a first threshold tailgating value for tailgating the first vehicle;

use the sensor data to determine whether the potential tailgater is changing lanes;

when the potential tailgater is determined to be changing lanes, wait a predetermined period of time;

after the predetermined period of time, receive updated sensor data from the sensor;

after the predetermined period of time use updated sensor data from the sensor to determine whether the potential tailgater meets a second threshold tailgating value; and

maneuver the first vehicle based on whether the potential tailgater meets the second threshold tailgating value.

2. The system of claim 1, wherein the first threshold tailgating value is identical to the second threshold tailgating value.

3. The system of claim 1, wherein the first threshold tailgating value is different from the second threshold tailgating value.

4. The system of claim 3, wherein the one or more processors are further configured to determine the first threshold tailgating value based on a current speed of the first vehicle, a current speed of the second vehicle, and a current distance between the first vehicle and the second vehicle.

5. The system of claim 4, wherein the one or more processors are further configured to determine the second threshold tailgating value based on a current speed of the first vehicle after the predetermined period of time, a current speed of the potential tailgater after the predetermined period of time, and a current distance between the first vehicle and the potential tailgater after the predetermined period of time.

6. The system of claim 1, wherein the first threshold tailgating value is defined in distance.

7. The system of claim 1, wherein the first threshold tailgating value is defined in time.

8. The system of claim 1, wherein the one or more processors are further configured to:

when the potential tailgater is determined to meet the second tailgating threshold value, identify the potential tailgater as a tailgater; and

maneuver the first vehicle includes maneuvering the first vehicle to a different lane from a current lane of the first vehicle.

9. The system of claim 8, wherein the one or more processors are further configured to:

after maneuvering the first vehicle to the different lane, allow the tailgater to pass the first vehicle; and

maneuver the first vehicle from the different lane into the current lane.

10. The system of claim 1, wherein the one or more processors are further configured to determine the first threshold tailgating value according to a threshold function having a first term that is dependent upon the speed of the first vehicle and a second term that is independent of the speed of the first vehicle.

11. The system of claim 10, wherein the one or more processors are further configured to:

determine the second term based upon a type of roadway on which the first vehicle is currently driving; and

determine the first term based upon the type of roadway on which the first vehicle is currently driving.

12. The system of claim 11, wherein the first term is determined to be zero when the type of roadway is a highway.

13. The system of claim 11, wherein the second term is determined to be zero when the type of roadway is a surface street.

14. The system of claim 10, wherein the first term and second term are fixed values.

15. The system of claim 1, wherein the one or more processors are further configured to:

after the predetermined period of time use the updated sensor data from the sensor to determine whether the potential tailgater is within a current lane of the first vehicle; and

maneuver the first vehicle based on whether the potential tailgater is within the current lane of the first vehicle.

16. The system of claim 1, further comprising the first vehicle.

17. A method for controlling aspects of a first vehicle, the method comprising:

receiving, by one or more processors, sensor data from a sensor;

detecting, using the sensor data, by the one or more processors, a second vehicle driving behind a first vehicle;

identifying, by the one or more processors, the second vehicle as a potential tailgater of the first vehicle when the second vehicle meets a first threshold tailgating value for tailgating the first vehicle;

using, by the one or more processors, the sensor data to determine whether the potential tailgater is changing lanes;

when the potential tailgater is determined to be changing lanes, waiting, by the one or more processors, a predetermined period of time;

after the predetermined period of time, receiving, by the one or more processors, updated sensor data from the sensor;

after the predetermined period of time, using, by the one or more processors, the updated sensor data to determine whether the potential tailgater meets a second threshold tailgating value; and

maneuvering, by the one or more processors, the first vehicle based on whether the potential tailgater meets the second threshold tailgating value.

18. The method of claim 17, further comprising:

when the potential tailgater is determined to meet the second tailgating threshold value, identifying, by the one or more processors, the potential tailgater as a tailgater; and

maneuvering, by the one or more processors, the first vehicle includes maneuvering the first vehicle to a different lane from a current lane of the first vehicle.

19. The method of claim 18, further comprising:

after maneuvering the first vehicle to the different lane, allowing, by the one or more processors, the tailgater to pass the first vehicle; and

maneuvering, by the one or more processors, the first vehicle from the different lane into the current lane.

20. The method of claim 17, further comprising determining the first threshold tailgating value according to a threshold function having a first term that is dependent upon a speed of the first vehicle and a second term that is independent of the speed of the first vehicle.