Vehicle driver assistance system and method

• US 20090177347A1
• Filed: 12/19/2008
• Published: 07/09/2009
• Est. Priority Date: 01/04/2008
• Status: Active Grant

• Current Assignee: ZF CV Systems Europe BV
• Original Assignee: Wabco GmbH (Wabco Holdings Incorporated)
• Inventors: Hoffman, Guido, Breuer, Karsten, Dieckmann, Thomas
• Granted Patent: US 8,195,373 B2
• Time in Patent Office: Days
• US Class Current: 701/29
• CPC Class Codes: B60T 7/22 initiated by contact of vehicle, e.g. bumper, with an external object, e.g. another vehicle , or by means of contactless obstacle detectors mounted on the vehicle
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2554/4042 Longitudinal speed
• CPC Class Codes: B60W 2554/804 Relative longitudinal speed
• CPC Class Codes: B60W 50/0205 Diagnosing or detecting failures; Failure detection models

Abstract

A driver assistance system includes a sensor for sensing the speed of a first vehicle equipped with the system, a sensor for detecting a vehicle traveling ahead, a sensor for determining the speed of the vehicle ahead, at least one driving-data sensor for sensing driving data characteristics, and an electronic controller programmed to trigger autonomous braking of the first vehicle when predetermined brake-trigger driving data exist, and to end the autonomous braking when predetermined driving data for terminating braking exist. In effecting termination of autonomous braking, the electronic controller is programmed to determine whether the sensor for detecting vehicles ahead is transmitting signals (i.e., is operational) but is not detecting any vehicle traveling ahead, and, if the sensor is operational and no vehicle traveling ahead is detected, to terminate autonomous braking when the speed of the first vehicle is less than the most recently determined speed of the vehicle ahead.

Claims

1. A driver assistance system for a vehicle, comprising

a first sensor constructed and arranged to sense the speed of said vehicle;

a second sensor constructed and arranged to sense a second vehicle traveling ahead of said vehicle;

a third sensor constructed and arranged to determine the speed of said second vehicle; and

an electronic controller adapted to (i) trigger autonomous braking of said vehicle based on preselected data for triggering braking, (ii) determine the operational condition of said second sensor, and (iii) terminate autonomous braking of said vehicle when (a) said second sensor is operational but is not sensing said second vehicle or any other vehicle ahead of said vehicle and (b) the speed of said vehicle is less than the most recently determined speed of said second vehicle.

2. The driver assistance system according to claim 1, wherein said second sensor is adapted to sense a distance between said vehicle and said second vehicle.

3. The driver assistance system according to claim 2, wherein said third sensor is adapted to (i) receive the speed of said vehicle from said first sensor, (ii) receive said distance from said second sensor and (iii) calculate the speed of said second vehicle from said speed data and said distance data.

4. The driver assistance system according to claim 1, wherein said controller is further adapted to override the termination of autonomous braking of said vehicle until said vehicle is at a standstill when said second sensor is non-operational.

5. The driver assistance system according to claim 1, wherein said third sensor is a Doppler radar sensor.

6. The driver assistance system according to claim 1, further comprising at least one driving-data sensor for sensing driving data characteristics of a driving condition of said vehicle.

7. The driver assistance system according to claim 6, wherein said at least one driving-data sensor is at least one of a yaw-rate sensor and a deceleration sensor.

8. The driver assistance system according to claim 1, wherein said second sensor is at least one of a multi-beam laser sensor and a radar sensor.

9. The driver assistance system according to claim 8, wherein said radar sensor is a Doppler radar sensor.

10. The driver assistance system according to claim 1, wherein said second sensor includes a video camera.

11. The driver assistance system according to claim 1, wherein said electronic controller is adapted to continually execute, during autonomous braking of said vehicle, (i) monitoring of the operational condition of said second sensor and (ii) termination of autonomous braking of said vehicle when said second sensor is operational but is not sensing said second vehicle or any other vehicle ahead of said vehicle, and the speed of said vehicle is less than the most recently determined speed of said second vehicle.

12. A vehicle, comprising a driver assistance system according to claim 1.

13. In a vehicle including a driver assistance system having a first sensor constructed and arranged to sense the speed of said vehicle, a second sensor constructed and arranged to sense a second vehicle traveling ahead of said vehicle, a third sensor constructed and arranged to determine the speed of said second vehicle, and an electronic controller adapted to trigger autonomous braking of said vehicle based on preselected data for triggering braking, a method for avoiding premature termination of autonomous braking, comprising the steps of (i) determining the operational condition of said second sensor, and (ii) terminating autonomous braking of said vehicle when (a) said second sensor is operational but is not sensing said second vehicle or any other vehicle ahead of said vehicle and (b) the speed of said vehicle is less than the most recently determined speed of said second vehicle.

14. The method according to claim 13, further comprising the step of overriding termination of autonomous braking of said vehicle until said vehicle is at a standstill when said second sensor is non-operational.

15. The method according to claim 13, wherein said steps of (i) determining the operational condition of said second sensor, and (ii) terminating autonomous braking of said vehicle when (a) said second sensor is operational but is not sensing said second vehicle or any other vehicle ahead of said vehicle and (b) the speed of said vehicle is less than the most recently determined speed of said second vehicle are effected continually during autonomous braking of said vehicle.