Method and Apparatus for Reducing Motor Vehicle Traffic Flow Instabilities and Increasing Vehicle Throughput

• US 20110093177A1
• Filed: 10/13/2010
• Published: 04/21/2011
• Est. Priority Date: 10/21/2009
• Status: Active Grant

• Current Assignee: Berthold K.P. Horn
• Original Assignee: Berthold K.P. Horn
• Inventors: Horn, Berthold K.P.
• Granted Patent: US 8,744,661 B2
• Time in Patent Office: Days
• US Class Current: 701/70
• CPC Class Codes: B60W 2050/0075 Automatic parameter input, automatic initialising or calibrating means
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2554/801 Lateral distance
• CPC Class Codes: B60W 2556/65 Data transmitted between vehicles
• CPC Class Codes: B60W 2720/106 Longitudinal acceleration
• CPC Class Codes: B60W 30/16 Control of distance between vehicles, e.g. keeping a distance to preceding vehicle

Abstract

A method and apparatus are disclosed for reducing traffic flow instabilities and increasing vehicle throughput by monitoring the distances and velocities of motor vehicles leading and following a center vehicle and controlling the velocities of the vehicles to maintain a steady relative distance between the center vehicle and the leading and following vehicles. Using distance and speed information derived from both leading and following vehicles reduces the loop gain of feedback needed below one (1) and diminishes traffic instabilities caused by “car following.”

Claims

1. A vehicle having a current speed sensor, a driver input and a mechanism to control forward motion of the vehicle, comprising:

a vehicle controller system secured in the vehicle, the vehicle controller system receiving inputs from the current speed sensor and the driver input and providing an output to the mechanism to control forward motion of the vehicle; and

one or more leading distance sensors, one or more leading speed sensors, one or more following distance sensors, and one or more following speed sensors, each of the sensors having an output that is provided to the vehicle controller system;

wherein the vehicle controller system provides the output to the mechanism to control forward motion of the vehicle as a function of the input from the current speed sensor, of the output from the one or more leading distance sensors, of the output of the one or more leading speed sensors, of the output of the one or more following distance sensors, and of the output of the one or more following speed sensors.

2. The vehicle of claim 1, wherein inputs from the driver input to the vehicle controller system can be selectively masked.

3. The vehicle of claim 1, wherein the vehicle controller system provides an output to the mechanism to control forward motion of the vehicle as a function of the outputs of the one or more leading distance sensors, of the one or more leading speed sensors, of the one or more following distance sensors, of the one or more following speed sensors, and of the current speed sensor.

4. The vehicle of claim 1, wherein the vehicle includes a fuel controller and a braking system and the controller system provides output to the fuel controller and to the braking system.

5. The vehicle of claim 4, wherein the vehicle controller system provides the output to the fuel controller and to the braking system according to the function:

a=ƒ

(k_d(d_l−

d_f)+k_v((v_l−

v_c)+(v_f−

v_c))

where

a is the acceleration control signal provided to the vehicle by the vehicle controller system;

d_l is the distance of a first (leading) vehicle in front of the vehicle;

d_t is the distance of a second (following) vehicle behind the vehicle;

v_l is the speed of the first (leading) vehicle;

v_c is the speed of the (controlled) vehicle;

v_f is the speed of the second (following) vehicle; and

k_d and k_v are gain factors.

6. The vehicle of claim 4, wherein the vehicle controller system provides the output to the fuel controller and to the braking system according to the function:

a=ƒ

(k_d(d_l−

d_f)+k_v((v_l−

v_c)+(v_f−

v_c))+k_c(v_des−

v_c))

where

a is the acceleration control signal provided to the vehicle by the vehicle controller system;

d_l is the distance of a first (leading) vehicle in front of the vehicle;

d_f is the distance of a second (following) vehicle behind the vehicle;

v_l is the speed of the first (leading) vehicle;

v_c is the speed of the (controlled) vehicle;

v_f is the speed of the second (following) vehicle;

v_des is the desired speed of the vehicle; and

k_d, k_v and k_c are gain factors.

7. The vehicle as claimed in claim 1, wherein the one or more leading distance sensors and the one or more following distance sensors are selected from the group consisting of radar sensors, lidar sensors, sonar sensors, machine vision sensors, image processing systems, a binocular stereo imaging system which exploits the parallax between images obtained using two spatially separated cameras, trinocular stereo systems and monocular systems.

8. The vehicle as claimed in claim 1, wherein the speed sensors are selected from the group of radar, lidar, and sonar systems that measure Doppler signals, or from machine vision and image processing systems.

9. A method of controlling the forward motion of a vehicle having a current speed sensor that outputs a current speed and a mechanism to control forward motion of the vehicle, comprising:

a vehicle controller system secured in the vehicle, the vehicle controller system receiving inputs from the current speed sensor and the driver input and providing an output to the mechanism to control forward motion of the vehicle; and

detecting a distance between a leading vehicle and the vehicle with a first detector and providing the detected distance between the leading vehicle and the vehicle on a first detector output;

detecting a relative speed between the leading vehicle and the vehicle with a second detector and providing the detected relative speed between the leading vehicle and the vehicle on a second detector output;

detecting a distance between a following vehicle and the vehicle on a third detector and providing the detected distance between the leading vehicle and the vehicle on a third detector output;

detecting a relative speed between the following vehicle and the vehicle with a fourth detector and providing the detected relative speed between the following vehicle and the vehicle on a fourth detector output; and

inputting the first detector output, the second detector output, the third detector output, the fourth detector output and the current speed to a vehicle controller and processing the detected distance between the leading vehicle and the controlled vehicle, the detected relative speed between the leading vehicle and the controlled vehicle, the detected distance between the following vehicle and the controlled vehicle, the detected relative speed between the following vehicle and the vehicle and the current speed to provide an output to the mechanism to control forward motion of the vehicle.

10. The method of claim 9, wherein the vehicle also has driver inputs provided to the vehicle control system wherein inputs from the driver input to the vehicle controller system can be selectively masked.

11. The method of claim 9, wherein the vehicle controller system provides an output to the mechanism to control forward motion of the vehicle as a function of the outputs of the one or more leading distance sensors, of the one or more leading speed sensors, of the one or more following distance sensors, of the one or more following speed sensors, and of the current speed sensor.

12. The method of claim 9, wherein the vehicle includes a fuel controller and a braking system and the vehicle controller system provides output to the fuel controller and to the braking system.

13. The method of claim 12, wherein the vehicle controller system provides the output to the fuel controller and to the braking system according to the function:

a=ƒ

(k_d(d_l−

d_f)+k_v((v_l−

v_c)+(v_f−

v_c))

where

a is the acceleration control signal provided to the vehicle by the vehicle controller system;

d_l is the distance of a first (leading) vehicle in front of the vehicle;

d_t is the distance of a second (following) vehicle behind the vehicle;

v_l is the speed of the first (leading) vehicle;

v_c is the speed of the (controlled) vehicle;

v_f is the speed of the second (following) vehicle; and

k_d and k_v are gain factors.

14. The method of claim 12, wherein the vehicle controller system provides the output to the fuel controller and to the braking system according to the function:

a=ƒ

(k_d(d_l−

d_f)+k_v((v_l−

v_c)+(v_f−

v_c))+k_c(v_des−

v_c))

where

a is the acceleration control signal provided to the vehicle by the vehicle controller system;

d_l is the distance of a first (leading) vehicle in front of the vehicle;

d_f is the distance of a second (following) vehicle behind the vehicle;

v_l is the speed of the first (leading) vehicle;

v_c is the speed of the (controlled) vehicle;

v_f is the speed of the second (following) vehicle;

v_des is the desired speed of the vehicle; and

k_d, k_v and k_c are gain factors.

15. The method as claimed in claim 9, wherein the one or more leading distance sensors and the one or more following distance sensors are selected from the group consisting of radar sensors, lidar sensors, sonar sensors, machine vision sensors, image processing systems, a binocular stereo imaging system which exploits the parallax between images obtained using two spatially separated cameras, trinocular stereo systems and monocular systems.

16. The method as claimed in claim 9, wherein the speed sensors are selected from the group of radar, lidar, and sonar systems that measure Doppler signals, or from machine vision and image processing systems.

17. A method of controlling the forward motion of a vehicle having a sensors and a mechanism to control forward motion of the vehicle, comprising:

inputting a current speed to a vehicle controller system secured in the vehicle; and

with a forward looking sensor mounted on the vehicle, detecting information about a first vehicle in front of the vehicle and providing the information about the first vehicle to the vehicle controller;

with a backward looking sensor mounted on the vehicle, detecting information about a second vehicle behind the vehicle and providing the information about the second vehicle to the vehicle controller; and

the vehicle controller controlling the forward motion of the vehicle based on the current speed, the information from the first vehicle and the information from the second vehicle.

18. The method as claimed in claim 17, wherein inputs from a driver of the vehicle are input the vehicle controller and the vehicle controller controls the forward motion of the vehicle, in part, based on inputs from the driver.

19. The method as claimed in claim 18, wherein the forward looking sensors and the backward looking sensors are selected from the group consisting of radar sensors, lidar sensors, sonar sensors, machine vision sensors, image processing systems, a binocular stereo imaging system which exploits the parallax between images obtained using two spatially separated cameras, trinocular stereo systems and monocular systems.

20. The method as claimed in claim 19, wherein the forward looking sensors and the backward looking sensors are selected from the group of radar, lidar, and sonar systems that measure Doppler signals, or from machine vision and image processing systems.