Road recognition system

• US 6,807,473 B1
• Filed: 04/09/2003
• Issued: 10/19/2004
• Est. Priority Date: 04/09/2003
• Status: Expired due to Fees

• Current Assignee: Continental Teves Incorporated (Continental AG)
• Original Assignee: Continental Teves Incorporated (Continental AG)
• Inventors: Tran, Vinh H.
• Primary Examiner(s): Marc-Coleman, Marthe Y.
• Application Number:
  US10/409,861
• Publication Number:
  US 20040204812A1
• Time in Patent Office: 559 Days
• Field of Search: 701/80, 701/71, 701/82, 701/91, 340/436, 340/903, 180/169
• US Class Current: 701/80
• CPC Class Codes: B60T 2210/12 Friction
• CPC Class Codes: B60T 8/172 Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters B60T8/17551 takes precedence
• CPC Class Codes: G01J 5/0022 for sensing the radiation of moving bodies
• CPC Class Codes: G01N 21/27 using photo-electric detection G01N21/31 takes precedence; circuits for computing concentration logarithmic circuits G06G7/24; photometric circuits in general G01J
• CPC Class Codes: G01N 21/84 Systems specially adapted for particular applications
• CPC Class Codes: G01S 15/02 using reflection of acoustic waves G01S15/66 takes precedence
• CPC Class Codes: G01S 15/86 Combinations of sonar systems with lidar systems; Combinations of sonar systems with systems not using wave reflection
• CPC Class Codes: G01S 15/931 of land vehicles
• CPC Class Codes: G06V 20/56 exterior to a vehicle by using sensors mounted on the vehicle

Abstract

An apparatus and method for detecting the road condition for use in a motor vehicle. The system and method detect road data through a temperature sensor, an ultrasonic sensor, and a camera. The road data is filtered for easier processing. A comparison of the filtered road data to reference data is made, and a confidence level of that comparison is generated. Based on the comparison of filtered road data to reference data, the road condition is determined. The driver may be informed and/or stability control systems may be adjusted based on the detected road surface condition.

Claims

1. A method for detecting the road condition for use in a motor vehicle, the method comprising the steps of:

detecting road data through a temperature sensor providing temperature data, an ultrasonic sensor providing roughness data, and a camera providing image data;

filtering the road data for processing;

comparing filtered road data to reference data and generating a confidence level of the comparison;

determining a road surface condition based on the comparison of filtered road data to reference data; and

determining a reliability number of the road surface condition determination based on the confidence level.

2. The method of claim 1, further comprising the step of informing the driver of the road surface condition when the reliability number is above a predetermined value.

3. The method of claim 1, further comprising the step of optimizing stability control systems of the vehicle in accordance with the detected road surface condition when the reliability number is above a predetermined value.

4. The method of claim 1, wherein the step of filtering road data includes employing a threshold frequency for ultrasonic data.

5. The method of claim 1, wherein the step of filtering road data includes taking an average of the ultrasonic data.

6. The method of claim 1, wherein the step of filtering road data includes applying a Fourier transform to the ultrasonic data.

7. The method of claim 1, wherein the step of determining a reliability number relies predominately on the comparison of the filtered and reference road data.

8. The method of claim 1, wherein the step of determining a reliability number incorporates the consistency of the road and filtered data for a given period of time.

9. The method of claim 1, wherein the step of determining a reliability number incorporates the amount of noise in the road data prior to filtering.

10. The method of claim 1, wherein the temperature sensor provides air temperature data and road temperature data.

11. A method for detecting the road condition for use in a motor vehicle, the method comprising the steps of:

detecting road data through a temperature sensor providing temperature data, an ultrasonic sensor providing roughness data, and a camera providing image data;

filtering the road data for processing, including compressing the image data;

comparing filtered road data to reference data and generating a confidence level of the comparison;

determining a road surface condition based on the comparison of filtered road data to reference data; and

determining a reliability number of the road surface condition determination based on the confidence level.

12. The method of claim 11, wherein compressing image data includes utilizing edge detection.

13. The method of claim 11, wherein compressing image data include utilizing line detection.

14. The method of claim 11, wherein compressing image data includes softening the image to reduce noise.

15. The method of claim 11, wherein compressing image data includes recognizing color.

16. A method for detecting road condition for use in a motor vehicle, the method comprising the steps of:

detecting road data through a temperature sensor providing temperature data, an ultrasonic sensor providing roughness data, and a camera providing image data;

filtering the road data for processing;

comparing filtered road data to reference data and generating a confidence level of the comparison;

determining a road surface condition, including an environment classification of road surface condition, based on the comparison of filtered road data to reference data; and

determining a reliability number of the road surface condition determination based on the on the confidence level.

17. The method of claim 16, wherein the step of determining an environment classification includes:

establishing a temperature of the air and the road;

selecting a portion of the reference data based on the temperature data;

comparing roughness data from the ultrasonic sensor to the selected portion of the reference data; and

comparing image data from the camera to the selected portion of the reference data.

18. A method for detecting the road condition for use in a motor vehicle, the method comprising the steps of:

detecting road data through a temperature sensor providing temperature data, an ultrasonic sensor providing roughness data, and a camera providing image data;

filtering the road data for processing;

comparing filtered road data to reference data and generating a confidence level of the comparison;

determining a road surface condition, including a surface classification of road surface condition, based on the comparison of filtered road data to reference data; and

determining a reliability number of the road surface condition determination based on the confidence level.

19. The method of claim 18, wherein the step of determining a surface classification first compares roughness data from the ultrasonic sensor and then compares image data from the camera to increase the confidence level.

20. A road condition detection system for a motor vehicle, the detection system comprising:

means for detecting road data through a temperature sensor providing temperature data, an ultrasonic sensor providing roughness data, and a camera providing image data;

means for filtering road data for easier processing;

means for comparing filtered road data to reference data and generating a confidence level of the comparison;

means for determining a road surface condition, including one of an environmental classification and a surface classification of road surface condition, based on the comparison of filtered road data to reference data; and

means for determining a reliability number of the road surface condition determination based on the confidence level.

21. The method of claim 20, wherein the filtering means compresses the image data.