AUTOMOTIVE DRIVE ASSIST SYSTEM WITH SENSOR FUSION OF RADAR AND CAMERA AND PROBABILITY ESTIMATION OF OBJECT EXISTENCE FOR VARYING A THRESHOLD IN THE RADAR

• US 20090251355A1
• Filed: 06/29/2007
• Published: 10/08/2009
• Est. Priority Date: 06/30/2006
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Nanami, Takeshi
• Granted Patent: US 8,199,046 B2
• Time in Patent Office: Days
• US Class Current: 342/27
• CPC Class Codes: G01S 13/867 Combination of radar systems with cameras
• CPC Class Codes: G01S 13/931 of land vehicles
• CPC Class Codes: G01S 2013/93185 Controlling the brakes
• CPC Class Codes: G01S 2013/9319 Controlling the accelerator
• CPC Class Codes: G01S 2013/932 using own vehicle data, e.g. ground speed, steering wheel direction
• CPC Class Codes: G01S 2013/9321 Velocity regulation, e.g. cruise control
• CPC Class Codes: G01S 2013/9325 for inter-vehicle distance regulation, e.g. navigating in platoons

Abstract

An ACC system (1) includes: a millimeter radar (10); a stereo camera (11); a preceding vehicle recognition ECU (20) that determines object type information indicating the detection status of these components; and a cruise control ECU (30) that controls a brake actuator (40) and an electronically-controlled throttle valves (41) based on object parameters and the object type information. With regard to the object detected by the millimeter wave radar (10) with the intensity of a received radio wave equal to or higher than a lower threshold value that is lower than higher threshold value, the object that is detected also by the stereo camera (11), or the object that was detected by the millimeter wave radar (10) with the intensity of a received radio wave equal to or higher than a higher threshold value is treated as the preceding vehicle candidate.

Claims

1. An object detection system comprising:

a first object detection unit that detects an object in an area near the system using a radar; and

an object determination section that determines whether the object in the area near the system is a subject of detection, using a result of detection by the first object detection unit,

wherein, with regard to the object whose existing probability is low, the object determination section treats the object, from which a radio wave whose intensity is equal to or higher than a first threshold value is being currently received by the first object detection unit, as the subject of detection, and

wherein, with regard to the object whose existing probability is high, the object determination section treats the object, from which a radio wave whose intensity is equal to or higher than a second threshold value that is lower than the first threshold value is being currently received by the first object detection unit, as the subject of detection.

2. The object detection system according to claim 1, wherein the object whose existing probability is high is the object from which a radio wave whose intensity was equal to or higher than the first threshold value was received in the past by the first object detection unit.

3. The object detection system according to claim 1, further comprising:

a second object detection unit that detects the object in the area near the system,

wherein the object determination section determines whether the object in the area near the system is the subject of detection, using a result of detection by the second object detection unit in addition to the result of detection by the first object detection unit, and

wherein the object whose existing probability is high is the object that is being currently detected by the second object detection unit.

4. The object detection system according to claim 3, wherein the second object detection unit detects the object by using image recognition.

8. A drive assist system for a vehicle provided with the object detection system according to claim 1, further comprising:

a fusion detection section that detects parameters indicating a distance, a relative speed, and a lateral offset between a host vehicle and the subject of detection;

a sensor that detects a drive status of the host vehicle;

a preceding vehicle-selecting section that compares a result of detection by the sensor with a position of the subject of detection based on the detected parameters to determine whether the object is in a path of the host vehicle, and selects a preceding vehicle based on the determination result; and

a drive control section that controls running speed of the host vehicle based on the parameters detected by the fusion detection section, and based on the determination and selection result of the preceding vehicle-selecting section.

5. An object detection system comprising:

a first object detection unit that detects an object in an area near the system using a radar;

a second object detection unit that takes an image of the area near the system, and detects an object in the area near the system based on the image; and

an object determination section that determines whether the object in the area near the system detected by at least one of the first and second object detection units is a subject of detection, using a result of detection by the first object detection unit, and a result of detection by the second object detection unit,

wherein, with regard to the object whose existing probability is low, the object determination section treats the object, from which a radio wave whose intensity is equal to or higher than a first threshold value is being currently received by the first object detection unit, as the subject of detection, and

wherein, with regard to the object whose existing probability is high, the object determination section treats the object, from which a radio wave whose intensity is equal to or higher than a second threshold value that is lower than the first threshold value is being currently received by the first object detection unit, as the subject of detection.

6. The object detection system according to claim 5, wherein the object whose existing probability is high is the object from which a radio wave whose intensity was equal to or higher than the first threshold value was received in the past by the first object detection unit.

7. The object detection system according to claim 5, wherein the object whose existing probability is high is the object that is being currently detected by the second object detection unit.

13. A drive assist system for a vehicle provided with the object detection system according to claim 5, further comprising:

a fusion detection section that detects parameters indicating a distance, a relative speed, and a lateral offset between a host vehicle and the subject of detection;

a sensor that detects a drive status of the host vehicle;

a preceding vehicle-selecting section that compares a result of detection by the sensor with a position of the subject of detection based on the detected parameters to determine whether the object is in a path of the host vehicle, and selects a preceding vehicle based on the determination result; and

a drive control section that controls running speed of the host vehicle based on the parameters detected by the fusion detection section, and based on the determination and selection result of the preceding vehicle-selecting section.

9. An object detection method, comprising:

detecting an object using a radar; and

determining whether the object is a subject of detection,

wherein the subject of detection includes;

(i) the object from which a radio wave whose intensity is equal to or higher than a first threshold value is being currently received by the radar; and

(ii) the object from which a radio wave whose intensity was equal to or higher than the first threshold value was received in the past, and from which a radio wave whose intensity is equal to or higher than a second threshold value that is lower than the first threshold value is being currently received.

10. An object detection method, comprising:

detecting an object using a radar;

taking an image, and detecting an object based on the image; and

determining whether the object detected in at least one of the preceding steps is a subject of detection,

wherein the subject of detection includes;

(i) the object from which a radio wave whose intensity is equal to or higher than a first threshold value is being currently received by the radar;

(ii) the object that is detected using the image, and from which a radio wave whose intensity is equal to or higher than a second threshold value that is lower than the first threshold value is being currently received; and

(iii) the object from which a radio wave whose intensity was equal to or higher than the first threshold value was received in the past, and from which a radio wave whose intensity is equal to or higher than the second threshold value that is lower than the first threshold value is being currently received.

11. (canceled)

12. (canceled)