Method and system for warning a driver of a vehicle about potential obstacles behind the vehicle

• US 8,952,799 B2
• Filed: 04/12/2012
• Issued: 02/10/2015
• Est. Priority Date: 04/12/2011
• Status: Active Grant

• Current Assignee: Conti Temic Microelectronic GmbH (Continental AG)
• Original Assignee: Conti Temic Microelectronic GmbH (Continental AG)
• Inventors: Irrgang, Peter, Kanzler, Steven Gerd, Schlensag, Andreas
• Primary Examiner(s): POPE, DARYL C
• Application Number:
  US13/445,337
• Publication Number:
  US 20120262284A1
• Time in Patent Office: 1,034 Days
• Field of Search: 340/933, 340/937, 340/435, 340/436, 340/438
• US Class Current: 340/435
• CPC Class Codes: B60W 2540/18 Steering angle
• CPC Class Codes: B60W 2554/00 Input parameters relating to objects
• CPC Class Codes: B60W 2554/4041 Position
• CPC Class Codes: B60W 2554/804 Relative longitudinal speed
• CPC Class Codes: B60W 30/0956 the prediction being responsive to traffic or environmental parameters
• CPC Class Codes: B60W 30/18036 Reversing
• CPC Class Codes: B60W 50/14 Means for informing the driver, warning the driver or prompting a driver intervention
• CPC Class Codes: G08G 1/168 Driving aids for parking, e.g. acoustic or visual feedback on parking space

Abstract

A method and system produce a warning signal to warn a driver of a vehicle about a potential obstacle crossing behind the vehicle, for example as the vehicle is backing out of a parking space. The system and method use a sensor to detect, monitor and track the position and velocity of a potential obstacle relative to the subject vehicle, in a detection space behind and to the sides of the vehicle, preferably to predict the probability that the trajectory of the potential obstacle will intersect with the trajectory of the subject vehicle at a critical time.

Claims

1. A method of warning a driver of a subject vehicle about a potential obstacle crossing behind said subject vehicle, comprising the steps:

a) with at least one sensor mounted on said subject vehicle, detecting a potential obstacle in a detection region extending behind and beside said subject vehicle, and producing sensor data representative of said potential obstacle detected by said at least one sensor;

b) in an evaluation arrangement mounted in said subject vehicle, evaluating said sensor data, and from said sensor data determining a relative position and a relative speed of said potential obstacle relative to said subject vehicle;

c) in said evaluation arrangement, determining, from said relative position and said relative speed, a probability that said potential obstacle will enter a critical zone encompassing said subject vehicle and extending a predetermined distance behind said subject vehicle;

d) in said evaluation arrangement, comparing said probability to a probability threshold, and generating a warning signal if said probability exceeds said probability threshold.

2. The method according to claim 1, further comprising acquiring a speed signal indicative of a vehicle speed of said subject vehicle, and evaluating said relative speed with reference to said vehicle speed to determine an obstacle speed of said potential obstacle.

3. The method according to claim 2, further comprising detecting with said sensor and evaluating in said evaluation arrangement a detected angle at which said potential obstacle relatively approaches said sensor on said subject vehicle, and evaluating said detected angle and said obstacle speed to determine two orthogonal speed components including a first speed component parallel to a longitudinal axis of said subject vehicle and a second speed component perpendicular to said longitudinal axis.

4. The method according to claim 1, further comprising detecting with said sensor and evaluating in said evaluation arrangement a detected angle at which said potential obstacle relatively approaches said sensor on said subject vehicle, and evaluating said detected angle and said relative speed to determine two orthogonal speed components including a first speed component parallel to a longitudinal axis of said subject vehicle and a second speed component perpendicular to said longitudinal axis.

5. The method according to claim 1, wherein said determining of said probability in said step c) comprises determining a first predicted trajectory of said potential obstacle from said relative position and said relative speed.

6. The method according to claim 5, further comprising acquiring a steering angle signal indicative of a steering angle of said subject vehicle, and further comprising acquiring a speed signal indicative of a vehicle speed of said subject vehicle, and wherein said determining of said probability in said step c) further comprises determining a second predicted trajectory of said subject vehicle from said steering angle and said vehicle speed and determining whether said first predicted trajectory crosses said second predicted trajectory at a coinciding time.

7. The method according to claim 1, wherein said predetermined distance to which said critical zone extends behind said subject vehicle is up to 6 m.

8. The method according to claim 1, further comprising emitting said warning signal as at least one of an optical signal, a haptic signal and an acoustic signal to warn said driver.

9. The method according to claim 8, further comprising triggering, with said warning signal, an automatic driving maneuver control of said subject vehicle.

10. The method according to claim 1, further comprising comparing said relative speed to a minimum speed threshold, and only generating said warning signal if said relative speed exceeds said minimum speed threshold.

11. The method according to claim 1, further comprising acquiring a speed signal indicative of a vehicle speed of said subject vehicle, comparing said vehicle speed to a maximum speed threshold, and only generating said warning signal if said vehicle speed is below said maximum speed threshold.

12. The method according to claim 1, wherein said potential obstacle is approaching said critical zone at an approach angle relative to a longitudinal axis of said subject vehicle, and said approach angle can take any and all values from 60°

to 120°

relative to said longitudinal axis.

13. The method according to claim 1, wherein said sensor has an angular detection range spanning at least 120°

.

14. The method according to claim 1, wherein said sensor is oriented with a sensing axis thereof directed at an angle of 110°

relative to a reference line extending forwardly parallel to a longitudinal axis of said subject vehicle.

15. The method according to claim 1, wherein said at least one sensor comprises a radar sensor for sensing said potential obstacle comprising another vehicle.

16. The method according to claim 15, wherein said at least one sensor further comprises another sensor of a different type or having different sensing characteristics relative to said radar sensor, for sensing said potential obstacle comprising a pedestrian.

17. A method of warning a driver of a subject vehicle about a potential obstacle crossing behind said subject vehicle, comprising the steps:

a) while said subject vehicle is moving in a rearward direction, with a sensor mounted on said subject vehicle detecting a potential obstacle in a detection region extending behind and beside said subject vehicle, and producing sensor data representative of said potential obstacle detected by said sensor;

b) in an evaluation arrangement mounted in said subject vehicle, evaluating said sensor data to determine a relative distance and a relative detected angle of said potential obstacle relative to said sensor mounted on said subject vehicle;

c) in said evaluation arrangement, monitoring a first progression of said relative distance over time and a second progression of said relative detected angle over time;

d) in said evaluation arrangement, determining from said first progression and said second progression a probability that said potential obstacle will intersect a critical zone encompassing said subject vehicle and extending a predetermined distance behind said subject vehicle; and

e) in said evaluation arrangement, comparing said probability to a probability threshold, and generating a warning signal if said probability exceeds said probability threshold.

18. The method according to claim 17, wherein said probability is determined in said step d) from only said first progression and said second progression without taking any other input data into account.