VEHICLE YAW RATE ESTIMATION SYSTEM

• US 20180001900A1
• Filed: 09/18/2017
• Published: 01/04/2018
• Est. Priority Date: 02/25/2015
• Status: Active Grant

• Current Assignee: Magna Electronics Incorporated (Magna International Incorporated)
• Original Assignee: Magna Electronics Incorporated (Magna International Incorporated)
• Inventors: Bajpai, Devendra
• Granted Patent: US 10,407,080 B2
• Time in Patent Office: Days
• CPC Class Codes: B60W 2520/125 Lateral acceleration
• CPC Class Codes: B60W 2520/28 Wheel speed
• CPC Class Codes: B60W 2540/18 Steering angle
• CPC Class Codes: B60W 40/114 Yaw movement

Abstract

A yaw rate estimation system for a vehicle includes a camera, a yaw rate sensor, wheel sensors, an accelerometer and a steering sensor. A control includes a processor that estimates the actual yaw rate of the vehicle by processing (i) a first yaw rate derived from yaw rate data provided by the yaw rate sensor, (ii) a second yaw rate derived from wheel sensor data provided by the wheel sensors, (iii) a third yaw rate derived from acceleration data provided by the accelerometer, and (iv) a fourth yaw rate derived from steering data provided by the steering sensor. The vehicular control system utilizes (i) image data captured by the camera as the vehicle is being driven along a road and (ii) the estimated actual yaw rate of the vehicle as the vehicle is being driven along the road.

Claims

1. A yaw rate estimation system for a vehicle equipped with a vehicular control system, said yaw rate estimation system comprising:

a camera disposed at a vehicle equipped with said yaw rate estimation system, wherein said camera is disposed at a windshield of the equipped vehicle and views through the windshield and forward of the equipped vehicle;

wherein the vehicular control system of the equipped vehicle comprises one of (i) a collision avoidance system, (ii) a collision mitigation system and (iii) a lane keeping system;

a yaw rate sensor disposed at the equipped vehicle;

wheel sensors disposed at wheels of the equipped vehicle;

an accelerometer disposed at the equipped vehicle and operable to determine acceleration of the equipped vehicle;

a steering sensor disposed at the equipped vehicle and operable to determine steering of the equipped vehicle;

a control disposed at the equipped vehicle, said control comprising a processor that estimates the actual yaw rate of the equipped vehicle by processing (i) a first yaw rate derived from yaw rate data provided to said control by said yaw rate sensor of the equipped vehicle, (ii) a second yaw rate derived from wheel sensor data provided to said control by said wheel sensors of the equipped vehicle, (iii) a third yaw rate derived from acceleration data provided to said control by said accelerometer, and (iv) a fourth yaw rate derived from steering data provided to said control by said steering sensor; and

wherein the vehicular control system utilizes (i) image data captured by said camera as the equipped vehicle is being driven along a road and (ii) the estimated actual yaw rate of the equipped vehicle as the equipped vehicle is being driven along the road.

2. The yaw rate estimation system of claim 1, wherein said accelerometer is operable to determine longitudinal acceleration of the equipped vehicle.

3. The yaw rate estimation system of claim 1, wherein said accelerometer is operable to determine lateral acceleration of the equipped vehicle.

4. The yaw rate estimation system of claim 1, wherein said control is operable to estimate the actual yaw rate of the equipped vehicle using statistical analysis of said first, second, third and fourth yaw rates.

5. The yaw rate estimation system of claim 4, wherein the statistical analysis uses Recursive Least Squares.

6. The yaw rate estimation system of claim 5, wherein the statistical analysis uses Confidence Weighted Average combined with Recursive Least Squares.

7. The yaw rate estimation system of claim 1, wherein said wheel sensors comprise wheel sensors of an anti-lock brake system of the equipped vehicle, and wherein said second yaw rate is derived from said anti-lock brake system wheel sensors of the equipped vehicle.

8. The yaw rate estimation system of claim 1, wherein said yaw rate sensor is operable to sense a left yaw rate of the equipped vehicle and a right yaw rate of the equipped vehicle.

9. The yaw rate estimation system of claim 1, wherein said yaw rate sensor is operable to sense positive and negative angular rotational velocity of the equipped vehicle about a local vertical axis of the equipped vehicle.

10. The yaw rate estimation system of claim 1, wherein output of said yaw rate sensor is communicated to said control via a communication bus of the equipped vehicle.

11. The yaw rate estimation system of claim 1, wherein said control, responsive to estimation of the actual yaw rate, provides yaw rate offset correction to correct said first yaw rate.

12. The yaw rate estimation system of claim 1, wherein said control, responsive to estimation of the actual yaw rate, provides noise filtering for the data received from said yaw rate sensor.

13. The yaw rate estimation system of claim 1, wherein said yaw rate sensor comprises one of (i) a piezoelectric device, (ii) a micromechanical device, and (iii) a microelectromechanical device.

14. A yaw rate estimation system for a vehicle equipped with a vehicular control system, said yaw rate estimation system comprising:

a camera disposed at a vehicle equipped with said yaw rate estimation system, wherein said camera is disposed at a windshield of the equipped vehicle and views through the windshield and forward of the equipped vehicle;

wherein the vehicular control system of the equipped vehicle comprises a collision avoidance system;

a yaw rate sensor disposed at the equipped vehicle;

wheel sensors disposed at wheels of the equipped vehicle;

an accelerometer disposed at the equipped vehicle and operable to determine acceleration of the equipped vehicle;

a steering sensor disposed at the equipped vehicle and operable to determine steering of the equipped vehicle;

a control disposed at the equipped vehicle, said control comprising a processor that estimates the actual yaw rate of the equipped vehicle by processing (i) a first yaw rate derived from yaw rate data provided to said control by said yaw rate sensor of the equipped vehicle, (ii) a second yaw rate derived from wheel sensor data provided to said control by said wheel sensors of the equipped vehicle, (iii) a third yaw rate derived from acceleration data provided to said control by said accelerometer, and (iv) a fourth yaw rate derived from steering data provided to said control by said steering sensor;

wherein output of said yaw rate sensor is communicated to said control via a communication bus of the equipped vehicle;

wherein said control is operable to estimate the actual yaw rate of the equipped vehicle using statistical analysis of said first, second, third and fourth yaw rates; and

wherein the vehicular control system utilizes (i) image data captured by said camera as the equipped vehicle is being driven along a road and (ii) the estimated actual yaw rate of the equipped vehicle as the equipped vehicle is being driven along the road.

15. The yaw rate estimation system of claim 14, wherein the statistical analysis uses Recursive Least Squares.

16. The yaw rate estimation system of claim 15, wherein the statistical analysis uses Confidence Weighted Average combined with Recursive Least Squares.

17. The yaw rate estimation system of claim 15, wherein said yaw rate sensor is operable to sense positive and negative angular rotational velocity of the equipped vehicle about a local vertical axis of the equipped vehicle.

18. A yaw rate estimation system for a vehicle equipped with a vehicular control system, said yaw rate estimation system comprising:

a camera disposed at a vehicle equipped with said yaw rate estimation system, wherein said camera is disposed at a windshield of the equipped vehicle and views through the windshield and forward of the equipped vehicle;

wherein the vehicular control system of the equipped vehicle comprises a lane keeping system;

a yaw rate sensor disposed at the equipped vehicle and operable to sense a left yaw rate of the equipped vehicle and a right yaw rate of the equipped vehicle;

wheel sensors disposed at wheels of the equipped vehicle;

an accelerometer disposed at the equipped vehicle and operable to determine one of (i) lateral acceleration of the equipped vehicle and (ii) longitudinal acceleration of the equipped vehicle;

a steering sensor disposed at the equipped vehicle and operable to determine steering of the equipped vehicle;

a control disposed at the equipped vehicle, said control comprising a processor that estimates the actual yaw rate of the equipped vehicle by processing (i) a first yaw rate derived from yaw rate data provided to said control by said yaw rate sensor of the equipped vehicle, (ii) a second yaw rate derived from wheel sensor data provided to said control by said wheel sensors of the equipped vehicle, (iii) a third yaw rate derived from acceleration data provided to said control by said accelerometer, and (iv) a fourth yaw rate derived from steering data provided to said control by said steering sensor;

wherein said wheel sensors comprise wheel sensors of an anti-lock brake system of the equipped vehicle, and wherein said second yaw rate is derived from said anti-lock brake system wheel sensors of the equipped vehicle; and

wherein the vehicular control system of the equipped vehicle utilizes (i) image data captured by said camera as the equipped vehicle is being driven along a road and (ii) the estimated actual yaw rate of the equipped vehicle as the equipped vehicle is being driven along the road.

19. The yaw rate estimation system of claim 18, wherein said yaw rate sensor is operable to sense positive and negative angular rotational velocity of the equipped vehicle about a local vertical axis of the equipped vehicle.

20. The yaw rate estimation system of claim 18, wherein said control, responsive to estimation of the actual yaw rate, provides yaw rate offset correction to correct said first yaw rate.