Collision avoidance system utilizing machine vision taillight tracking

• US 6,317,691 B1
• Filed: 02/16/2000
• Issued: 11/13/2001
• Est. Priority Date: 02/16/2000
• Status: Expired due to Term

• Current Assignee: HRL Laboratories LLC (The Boeing Co.)
• Original Assignee: HRL Laboratories LLC (The Boeing Co.)
• Inventors: Owechko, Yuri, Narayan, Srinivasa
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): Marc-Coleman, Marthe
• Application Number:
  US09/504,634
• Time in Patent Office: 636 Days
• Field of Search: 701/45, 701/300, 701/301, 701/28, 701/117, 382/171, 382/168, 382/170, 340/963, 340/961, 340/436
• US Class Current: 701/301
• CPC Class Codes: G08G 1/165 for passive traffic, e.g. including static obstacles, trees
• CPC Class Codes: G08G 1/166 for active traffic, e.g. moving vehicles, pedestrians, bikes

Abstract

A vehicle-mounted sensing method and apparatus capable of monitoring the relative speed, distance, and closure rate between a sensor-equipped host vehicle and a sensed target object. The sensor uses an electronic camera to passively collect information and to provide the information to a system that identifies objects of interest using visual clues such as color, shape, and symmetry. The object'"'"'s proximity may be determined, to a first approximation, by taking advantage of symmetrical relationships inherent in the vehicle of interest. The method and apparatus are particularly well-suited vehicular safety systems to provide for optimal risk assessment and deployment of multiple safety systems.

Claims

1. An apparatus for collision avoidance utilizing taillight tracking comprising:

a. at least one sensor for providing data, the at least one sensor including an image sensor having front and a lens for gathering image data, said lens including a focal axis, and said image data including color image components;

b. a data processing device operatively connected with the at least one sensor to receive and process data therefrom, said data processing device including;

i. means for isolating the colored image components from the image data;

ii. means for performing a dilation and size filtering operation on the colored image components to provide selectively enhanced color image components;

iii. means for identifying taillight pairs in the selectively enhanced color image components using a one-dimensional limited horizontal shift autocorrelation, with each of the identified taillight pairs having a taillight separation;

iv. means for using the taillight separation of each of the identified taillight pairs to determine a value of a distance of each of the taillight pairs from the image sensor;

v. means for determining the taillight pair most aligned with the focal axis of the lens and in front to the image sensor;

vi. means for controlling the means set forth in sub steps i to v of the present claim to generate, over time, a plurality of values of the distance from the image sensor to the taillight pair most aligned with the focal axis of the lens and in front to the image sensor, said values including a first most recent value and a second most recent value;

vii. means for storing the first most recent value and the second most recent value of the distance from the image sensor to the taillight pair most aligned with the focal axis of the lens and in front to the image sensor; and

viii. means for comparing the first most recent value and the second most recent value of the distance from the image sensor to the taillight pair most aligned with the focal axis of the lens and in front to the image sensor to determine a value of a rate-of-closure therebetween; and

c. a safety system functionally connected with the data processing device, said safety system configured to receive the value of the rate-of-closure between the image sensor and the taillight pair most aligned with the focal axis of the lens and in front to the image sensor, and to activate when the value of the rate of closure exceeds a threshold value.

2. An apparatus for collision avoidance utilizing taillight tracking as set forth in claim 1, wherein the image sensor is an electronic color camera and wherein the at least one sensor further includes a speed sensor and a steering wheel position sensor.

3. An apparatus for collision avoidance utilizing taillight tracking as set forth in claim 1, wherein the safety system includes at least one component selected from the group consisting of an output to an audio alarm, an output to a visual alarm, and an output to an airbag deployment algorithm.

4. An apparatus for collision avoidance utilizing taillight tracking as set forth in claim 1, wherein the safety system includes at least one component selected from the group consisting of an audio alarm having adjustable sound frequency and sound volume, a heads-up display, a LED, and a visual alarm including at least one flashing light.

5. An apparatus for collision avoidance utilizing taillight tracking as set forth in claim 1, wherein the image sensor is selected from the group consisting of a CCD color camera and a CMOS color camera.

6. An apparatus for collision avoidance utilizing taillight tracking as set forth in claim 1, wherein the apparatus is mounted inside a substantially rigid housing, the substantially rigid housing is adapted to be detachably attached within the passenger compartment of a vehicle.

7. An apparatus for collision avoidance utilizing taillight tracking as set forth in claim 6, wherein the substantially rigid housing is adapted for attachment near an internally mounted rearview mirror.

8. An apparatus for collision avoidance utilizing taillight tracking as set forth in claim 7, wherein the image sensor is selected from the group consisting of a CCD color camera and a CMOS color camera.

9. An apparatus for collision avoidance utilizing taillight tracking as set forth in claim 7, wherein the at least one sensor provides information to the data processor via a wireless interface.

10. An apparatus for collision avoidance utilizing taillight tracking as set forth in claim 6, wherein the image sensor is selected from the group consisting of a CCD color camera and a CMOS color camera.

11. An apparatus for collision avoidance utilizing taillight tracking as set forth in claim 1 wherein the at least one sensor provides information to the data processor via a wireless interface.

12. A method for predicting rear-end collisions comprising the steps of;

a. collecting data using at least one sensor, the at least one sensor including an image sensor having a front and a lens for gathering image data, said lens including a focal axis, and said image data including color image components;

b. providing said data to a data processor;

c. processing said data in the data processor by sub-steps including;

i. isolating the color image components from the image data;

ii. performing a dilation and size filtering operation on the color image components to provide selectively enhanced color image components;

iii. identifying taillight pairs in the selectively enhanced color image components using a one-dimensional limited horizontal shift autocorrelation, with each of the identified taillight pairs having a taillight separation;

iv. using the taillight separation of each of the identified taillight pairs to determine a value of a distance of each of the taillight pairs from the image sensor;

v. determining the taillight pair most aligned with the focal axis of the lens, and in front of the image sensor;

vi. controlling the sub-steps set forth in sub-steps i to v of the present claim to generate, over time, a plurality of values of the distance from the image sensor to the taillight pair most aligned with the focal axis of the lens and in front to the image sensor, said values including a first most recent value and a second most recent value;

vii. storing the first most recent value and the second most recent value of the distance from the image sensor to the taillight pair most aligned with the focal axis of the lens and in front to the image sensor; and

viii. comparing the first most recent value and the second most recent value of the distance from the image sensor to the taillight pair most aligned with the focal axis of the lens and in front of the image sensor to determine the value of the rate-of-closure therebetween;

d. functionally connecting the data processor with a safety system, wherein said safety system receives, from the data processor, a value of a rate-of-closure between the image sensor and the taillight pair most aligned with the focal axis of the lens and in front of the image sensor, said safety system activating when the value of the rate-of-closure exceeds a threshold value.

13. A method for predicting rear-end collisions as set forth in claim 12, wherein the at least one sensor further includes at least one additional sensor selected from the group consisting of a speed sensor, a temperature sensor, and a steering wheel position sensor, and wherein the at least one additional sensor is used for collecting and providing additional data to the data processor, where said data processor further includes means for using the additional data to define the threshold value used in the activation of the safety system.

14. A method for predicting rear-end collisions as set forth in claim 13, wherein the step of providing the data to the processor is performed via a wireless interface.