Obstacle avoidance processing method for vehicles using an automated highway system

• US 6,026,347 A
• Filed: 05/30/1997
• Issued: 02/15/2000
• Est. Priority Date: 05/30/1997
• Status: Expired due to Term

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Schuster, Steven K.
• Primary Examiner(s): Louis-Jacques, Jacques H.
• Assistant Examiner(s): Beaulieu, Yonel
• Application Number:
  US08/865,817
• Time in Patent Office: 991 Days
• Field of Search: 701/301, 701/200, 701/300, 701/96, 701/23, 701/24, 701/25, 701/26, 701/27, 180/167-9, 180/168, 340/435, 340/6, 340/903, 340/4, 340/436, 342/70, 342/71
• US Class Current: 701/301
• CPC Class Codes: B62D 1/28 non-mechanical , e.g. following a line or other known markers
• CPC Class Codes: G08G 1/164 Centralised systems, e.g. external to vehicles

Abstract

A method for use in vehicles using lanes of an automated highway to avoid collisions with obstacles. A set of decision rules are embodied in a processor that are used in each vehicle to determine whether affected vehicles should change lanes or brake to minimize the expected impact with an obstacle. The presence of an obstacle in one of the lanes is detected by a lead vehicle or by sensors on the highway. The processor in the lead vehicle, or at a traffic management facility, probabilistically estimates the position of the obstacle at each of a plurality of times subsequent to detection. At each of the times, a course of action for all affected vehicles is determined by the processor in the lead vehicle based upon the best current estimate of position of the obstacle, knowledge of any previous action that has been taken, positions and velocities of the affected vehicles, and the geometry of the highway. At each of the times, each of the affected vehicles is commanded to perform an avoidance maneuver that is coordinated with the other affected vehicles, wherein affected vehicles brake and change lanes to avoid collision with the obstacle and with other vehicles. At each of the times, commands are sent to each affected vehicle that cause them to perform hard braking, light braking, maintain speed, resume previous speed, perform a lane change, abort a lane change or create a gap, so as to minimize the impact of the vehicles with the obstacle.

Claims

1. An obstacle avoidance method for use with automated vehicles that use an automated highway having at least two adjacent automated lanes, that minimizes the impact of the automated vehicles with an obstacle, said method comprising the steps of:

providing a set of decision rules for determining whether affected vehicles that could potentially impact the obstacle should change lanes or brake to minimize the expected impact with the obstacle;

sensing the presence of the obstacle in one of the automated lanes;

determining by an iterative process a series of coordinated avoidance maneuvers for affected vehicles in the lane containing the obstacle and in lanes adjacent to the lane containing the obstacle in accordance with the set of decision rules, an estimate of the position of the obstacle, the positions and velocities of other affected vehicles and the geometry of the highway; and

causing each of the affected vehicles to perform the series of coordinated avoidance maneuvers to avoid collision with the obstacle and with the other affected vehicles.

2. The method of claim 1 wherein the estimated position of the obstacle is treated probabilistically to minimize the expected drop in forward vehicle speed due to the collision with the obstacle.

3. The method of claim 1 wherein the estimated position of the obstacle is determined using sensor measurements.

4. The method of claim 1 wherein the series of coordinated maneuvers cause vehicles in the same lane as the obstacle to change lanes in the smallest possible safe distance.

5. The method of claim 1 wherein, upon each iteration, said determining step includes the step of determining the series of coordinated avoidance maneuvers using an updated estimate of the location of the obstacle and knowledge of previous actions that have been taken.

6. The method of claim 1 wherein the coordinated avoidance maneuvers are selected from the group of:

hard braking, light braking, maintaining speed, resuming previous speed, performing a lane change, aborting a lane change or creating a gap.

7. The method of claim 1 wherein the automated vehicles communicate with a traffic management facility responsible for monitoring and regulating traffic flow.

8. The method of claim 1 wherein the automated vehicles communicate with each other using transponders.

9. An obstacle avoidance method for use with automated vehicles that use an automated highway having at least two adjacent automated lanes, wherein all vehicles using these lanes are automated and move in the same direction in both lanes, and wherein an obstacle detection sensor is provided that estimates the position and velocity of obstacles and wherein the position of the vehicles on the highway is known, and wherein vehicles communicate with each other, and wherein each vehicle includes a processor that processes sensed signals and commands, and includes braking, steering and engine management systems responsive to commands from other vehicles to brake, accelerate, or change lanes, said method comprising:

a decision-making process that iterates three times, and wherein on each iteration, the best current estimate of position of an obstacle, knowledge of any previous action that has been taken, positions and velocities of all vehicles within the operating range of the vehicle, and the geometry of the highway is used to determine a course of action for affected vehicles, and wherein the highway is divided into a series of longitudinal zones, and wherein at each of three decision times, an action is chosen based on the estimate of the zone in which the obstacle is located, and on the relative position of the vehicles that are in the lane containing the obstacle and adjacent lanes;

and wherein vehicles respond to orders that have been transmitted, and perform hard braking, light braking, maintain speed, resume previous speed, perform a lane change, abort a lane change or create a gap, as commanded, and wherein simultaneous additional sensor measurements are taken on a lead vehicle, or sensors on the highway, to improve the estimate of the position of the obstacle, and wherein the method iterates, using the updated estimate of the position of the obstacle, and a knowledge of the previous actions that have been commanded, to generate a new set of commands for the affected vehicles.

10. The method of claim 9 wherein vehicles communicate with a traffic management facility responsible for monitoring and regulating traffic flow.

11. The method of claim 9 wherein vehicles communicate with each other using transponders.

12. An obstacle avoidance method for use with automated vehicles that use an automated highway having at least two adjacent automated lanes, that minimizes the impact of the automated vehicles with a non-vehicle obstacle, said method comprising the steps of:

providing a set of decision rules for determining whether affected vehicles that could potentially impact the non-vehicle obstacle should change lanes or brake to minimize the expected impact with the obstacle;

sensing the presence of the non-vehicle obstacle in one of the automated lanes; and

causing the affected vehicles to perform the series of coordinated avoidance maneuvers to avoid collision with the non-vehicle obstacle and with the other affected vehicles.

13. The method of claim 12 wherein an estimated position of the obstacle is treated probabilistically to minimize the expected drop in forward vehicle speed due to the collision with the obstacle.

14. The method of claim 12 wherein an estimated position of the obstacle is determined using sensor measurements.

15. The method of claim 12 wherein the series of coordinated avoidance maneuvers cause vehicles in the same lane as the obstacle to change lanes in the smallest possible safe distance.

16. The method of claim 12 further comprising the step of determining by an iterative process a series of coordinated avoidance maneuvers for affected vehicles in the lane containing the obstacle and in lanes adjacent to the lane containing the obstacle in accordance with the set of decision rules, an estimate of the position of the obstacle, the positions and velocities of other affected vehicles and the geometry of the highway.

17. The method of claim 12 wherein, upon each iteration, said determining step includes the step of determining the series of coordinated avoidance maneuvers using an updated estimate of the location of the obstacle and knowledge of previous actions that have been taken.

18. The method of claim 12 wherein the automated vehicles communicate with a traffic management facility responsible for monitoring and regulating traffic flow.

19. The method of claim 12 wherein the automated vehicles communicate with each other using transponders.

20. An obstacle avoidance method for use with automated vehicles that use an automated highway having at least two adjacent automated lanes, that minimizes the impact of the automated vehicles with an obstacle, said method comprising the steps of:

providing a set of decision rules for determining whether affected vehicles that could potentially impact the obstacle should change lanes or brake to minimize the expected impact with the obstacle;

sensing the presence of the obstacle in one of the automated lanes;

causing each of the affected vehicles to perform the series of coordinated avoidance maneuvers in accordance with the set of decision rules wherein the affected vehicles cooperatively brake and change lanes to avoid collision with the obstacle and with the other affected vehicles;

wherein the probabilistic estimate of the position of the obstacle is determined by a decision-making process that iterates a plurality of times, wherein on each iteration, the best current estimate of position of the obstacle, knowledge of any previous action that has been taken, positions and velocities of the affected vehicles, and the geometry of the highway, are processed to determine a course of action for affected vehicles;

and wherein the highway is divided into a series of longitudinal zones, and at each decision time, an action is chosen based on the best estimate of the zone in which the obstacle is located, and on the relative position of the vehicles that are in the lane containing the obstacle and adjacent lanes;

and wherein commands are sent to each affected vehicle that cause them to perform hard braking, light braking, maintain speed, resume previous speed, perform a lane change, abort a lane change or create a gap, as commanded;

and wherein the estimate of the position of the obstacle is improved on each iteration of the decision-making process and wherein new commands are generated for the affected vehicles after each iteration that minimize the impact of the automated vehicles with the obstacle.