Method and system for evaluating inter-vehicle traffic gaps and time instances to perform a lane change maneuver

• US 10,317,902 B2
• Filed: 02/17/2017
• Issued: 06/11/2019
• Est. Priority Date: 02/22/2016
• Status: Active Grant

• Current Assignee: Volvo Car Corporation (AB Volvo)
• Original Assignee: Volvo Car Corporation (AB Volvo)
• Inventors: Nilsson, Julia, Brannstrom, Mattias Erik
• Primary Examiner(s): Black, Thomas G
• Assistant Examiner(s): Kong, Sze-Hon
• Application Number:
  US15/435,815
• Publication Number:
  US 20170242435A1
• Time in Patent Office: 844 Days
• CPC Class Codes: B60W 2520/105 Longitudinal acceleration
• CPC Class Codes: B60W 2552/00 Input parameters relating to infrastructure
• CPC Class Codes: B60W 2554/4049 Relationship among other objects, e.g. converging dynamic objects
• CPC Class Codes: B60W 2554/801 Lateral distance
• CPC Class Codes: B60W 2554/802 Longitudinal distance
• CPC Class Codes: B60W 2554/804 Relative longitudinal speed
• CPC Class Codes: B60W 30/18163 Lane change; Overtaking manoeuvres
• CPC Class Codes: B60W 60/0011 involving control alternatives for a single driving scenario, e.g. planning several paths to avoid obstacles
• CPC Class Codes: G08G 1/167 Driving aids for lane monitoring, lane changing, e.g. blind spot detection

Abstract

A method and system for evaluating inter-vehicle traffic gaps and time instances to perform a lane change maneuver is described. The method includes determining a set of trajectories which respectively constitutes an approximation of the feasible motion of the ego vehicle, evaluating the set of trajectories on the available inter-vehicle traffic gaps and time instances to perform the lane change maneuver over a prediction horizon to select a subset of feasible inter-vehicle traffic gaps and time instances to perform the lane change maneuver and to establish a corresponding set of lane change trajectories, evaluating the set of lane change trajectories on the subset of feasible inter-vehicle traffic gaps and time instances from a safety critical perspective, and selecting a preferred lane change trajectory, with corresponding inter-vehicle traffic gap and time instance, to perform the lane change maneuver.

Claims

1. A method for evaluating inter-vehicle traffic gaps and time instances to perform a lane change maneuver, the method to be performed by a system on-board an ego vehicle, the ego vehicle travelling in a current lane of a road, the road also comprising a target lane adjacent to the current lane, the lane change maneuver including the ego vehicle changing from the current lane to an inter-vehicle traffic gap in the target lane, the method comprising:

(a) determining a set of trajectories which respectively constitutes an approximation of feasible motion of the ego vehicle assuming a number of acceleration profiles of the ego vehicle;

(b) evaluating the set of trajectories on available inter-vehicle traffic gaps and time instances to perform the lane change maneuver over a prediction horizon to select a subset of feasible inter-vehicle traffic gaps and time instances to perform the lane change maneuver and to establish a corresponding set of lane change trajectories;

(c) evaluating the set of lane change trajectories on the subset of feasible inter-vehicle traffic gaps and time instances from a safety critical perspective taking a safety critical event into account comprising a surrounding vehicle braking or performing a lane change maneuver; and

(d) selecting a lane change trajectory from the evaluated set of lane change trajectories, with corresponding inter-vehicle traffic gap and time instance, to perform the lane change maneuver.

2. The method according to claim 1 wherein the number of acceleration profiles are within a range going from a minimum acceleration of the ego vehicle to a maximum acceleration of the ego vehicle.

3. The method according to claim 1 wherein (b) comprises determining if a trajectory determined in (a) allows the ego vehicle to enter a corresponding lane-change region of a certain inter-vehicle traffic gap and remain in the lane-change region for a minimum time, and thereafter safely be positioned in a corresponding inter-vehicle traffic gap region in the target lane over the prediction horizon.

4. The method according to claim 1 wherein (b) comprises the ego vehicle maintaining a minimum safe distance to at least one surrounding object.

5. The method according to claim 1 wherein the safety critical event comprises a preceding vehicle making a brake maneuver.

6. The method according to claim 3 wherein a velocity of the ego vehicle is constrained in the lane-change region.

7. The method according to claim 1 wherein (d) is performed by selecting a trajectory for which one or more required control signals for the ego vehicle has the smallest magnitude.

8. A system for evaluating inter-vehicle traffic gaps and time instances to perform a lane change maneuver, the lane change maneuver to be performed when an ego vehicle travels in a current lane of a road, the road also comprising a target lane adjacent to the current lane, the lane change maneuver including the ego vehicle changing from the current lane to an inter-vehicle traffic gap in the target lane, the system comprising:

a determining unit for determining a set of trajectories which respectively constitutes an approximation of feasible motion of the ego vehicle assuming a number of acceleration profiles of the ego vehicle;

a first evaluating unit for evaluating the set of trajectories on available inter-vehicle traffic gaps and time instances to perform the lane change maneuver over a prediction horizon to select a subset of feasible inter-vehicle traffic gaps and time instances to perform the lane change maneuver and to establish a corresponding set of lane change trajectories;

a second evaluating unit for evaluating the set of lane change trajectories on the subset of feasible inter-vehicle traffic gaps and time instances from a safety critical perspective taking a safety critical event into account comprising a surrounding vehicle braking or performing a lane change maneuver; and

a selecting unit for selecting a lane change trajectory from the evaluated set of lane change trajectories, with corresponding inter-vehicle traffic gap and time instance, to perform the lane change maneuver.

9. The system according to claim 8 further comprising a sensing system for determining relative positions or velocities of at least one surrounding object.

10. An automated lane change system comprising the system according to claim 8.

11. An advanced driver assistance system comprising the automated lane change system according to claim 10.

12. A vehicle comprising the system according to claim 8.

13. A vehicle comprising the automated lane change system according to claim 10.

14. A vehicle comprising the advanced driver assistance system according to claim 11.

15. A method for evaluating inter-vehicle traffic gaps and time instances for use by a host vehicle to perform a lane change maneuver from a current lane of a road to an inter-vehicle traffic gap in a target lane adjacent the current lane, the method comprising:

(a) determining a set of trajectories which respectively represent potential motion of the host vehicle assuming a number of acceleration profiles of the host vehicle;

(b) evaluating the set of trajectories on available inter-vehicle traffic gaps and time instances to perform the lane change maneuver over a prediction horizon to thereby select a set of inter-vehicle traffic gaps and time instances and to establish a corresponding set of lane change trajectories;

(c) evaluating the set of lane change trajectories on the set of inter-vehicle traffic gaps and time instances based on a safety critical event comprising a surrounding vehicle braking or performing a lane change maneuver; and

(d) selecting a lane change trajectory from the evaluated set of lane change trajectories, with corresponding inter-vehicle traffic gap and time instance, to perform the lane change maneuver.

16. The method according to claim 15 further comprising the host vehicle performing the selected lane change maneuver.

17. The method according to claim 15 wherein (c) comprises applying a deceleration profile which allows the host vehicle to maintain at least a minimum distance to a surrounding vehicle to thereby avoid a collision with the surrounding vehicle.

18. The method according to claim 15 wherein (b) comprises determining if a trajectory determined in (a) allows the host vehicle to enter a corresponding lane-change region of a certain inter-vehicle traffic gap and remain in the lane-change region for a minimum time, and thereafter safely be positioned in a corresponding inter-vehicle traffic gap region in the target lane over the prediction horizon.

19. The method according to claim 15 wherein the safety critical event comprises the surrounding vehicle braking, and wherein the surrounding vehicle is a preceding vehicle.

20. The method according to claim 15 wherein the safety critical event comprises the surrounding vehicle performing a lane change maneuver.