Enhanced yaw rate estimation and diagnosis for vehicular applications

• US 20030042790A1
• Filed: 08/28/2002
• Published: 03/06/2003
• Est. Priority Date: 08/29/2001
• Status: Active Grant

• Current Assignee: GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust), Steering Solutions IP Holding Corporation (Nexteer Automotive Group Ltd.)
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Amberkar, Sanket
• Granted Patent: US 6,623,089 B2
• Time in Patent Office: Days
• US Class Current: 303/140
• CPC Class Codes: B60T 2250/03 Vehicle yaw rate
• 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: B62D 7/159 characterised by computing methods or stabilisation processes or systems, e.g. responding to yaw rate, lateral wind, load, road condition

Abstract

A method for estimating the yaw rate of a vehicle. The method includes receiving at least one signal indicative of a vehicular lateral acceleration and receiving at least one signal indicative of a vehicular wheel velocity. A plurality of yaw rate estimation functions are provided. A first yaw rate estimation function of the plurality of yaw rate estimation functions is selected in response to at least one of the received signals. A first estimated yaw rate is estimated in accordance with the selected first yaw rate estimation function and at least two signals each indicative of a wheel velocity. If the first estimated yaw rate is not within a threshold value of an actual measured yaw rate, a second yaw rate estimation function is selected to obtain a second estimated yaw rate using a signal indicative of lateral acceleration for correlation with the actual measured yaw rate.

Claims

1. A method for estimating the yaw rate of a vehicle, comprising:

receiving at least one signal indicative of a vehicular lateral acceleration;

receiving at least one signal indicative of a vehicular velocity;

providing a plurality of yaw rate estimation functions;

selecting a first yaw rate estimation function of said plurality of yaw rate estimation functions in response to at least one of said received signals; and

estimating a first estimated yaw rate in accordance with the selected said first yaw rate estimation function and at least one of said received signals.

2. The method as defined in claim 1, further comprising:

measuring a yaw rate with a yaw rate sensor;

comparing said measured yaw rate with said first estimated yaw rate; and

detecting an inaccurate measured yaw rate in accordance with the comparison when the comparison is not within a selected threshold value.

3. The method as defined in claim 2, further comprising:

selecting a second yaw rate estimation function of said plurality of yaw rate estimation functions upon said detection of said inaccurate yaw rate; and

estimating a second estimated yaw rate in accordance with said selecting said second yaw rate estimation function and another signal of said received signals.

4. The method as defined in claim 3, further comprising:

comparing said measured yaw rate with said second estimated yaw rate; and

detecting an inaccurate measured yaw rate in accordance with the comparison when the comparison is not within said selected threshold value.

5. The method as defined in claim 4, further comprising:

generating a yaw rate sensor fault signal indicative of a failed yaw rate sensor.

6. The method as defined in claim 1, wherein said at least one signal indicative of said vehicular velocity includes a wheel velocity signal and said first yaw rate estimation function estimates said first yaw rate using at least two wheel velocities and a track width therebetween.

7. The method as defined in claim 3, wherein said at least one signal indicative of said vehicular velocity includes a lateral acceleration signal and said second yaw rate estimation function estimates said second yaw rate using said lateral acceleration signal and a signal indicative of effective vehicle velocity.

8. The method as defined in claim 7, wherein said signal indicative of effective vehicle velocity is generated from a vehicle transmission.

9. The method as defined in claim 6, wherein said first yaw rate estimation function is selected when an effective vehicular velocity is less than about 5 kph.

10. The method as defined in claim 1, wherein said first yaw rate estimation function is a wheel velocity based function configured to estimate yaw rate of the vehicle.

11. The method as defined in claim 10, wherein said wheel velocity based function is set as a default for estimation of yaw rate.

12. A method for estimating the yaw rate of a vehicle, comprising:

providing a plurality of signals indicative of one of a wheel speed and a lateral acceleration of the vehicle;

estimating a first estimated yaw rate using at least two wheel speed signals from opposing wheels and associated track width therebetween;

correlating an actual measured yaw rate with said first estimated yaw rate to determine if said first estimated yaw rate is invalid; and

estimating a second estimated yaw rate using an actual measured lateral acceleration and an effective vehicle velocity if said first estimated yaw rate is invalid.

13. The method as defined in claim 12, wherein said correlating includes determining a difference between said actual measured yaw rate and said first estimated yaw rate;

and

determining that said first estimated yaw rate is invalid if a difference between said actual measured yaw rate and said first estimated yaw rate is not within a selected threshold.

14. The method as defined in claim 12, further comprising:

correlating said actual measured yaw rate with said second estimated yaw rate to determine if said second estimated yaw rate is invalid;

determining that said actual measured yaw rate is invalid if a difference between said actual measured yaw rate and said second estimated yaw rate is not within a selected threshold; and

generating a signal indicative of a failed yaw rate sensor if said actual measured yaw rate is determined to be invalid.

15. A storage medium encoded with a machine readable computer program code for estimating a yaw rate of a vehicle, the storage medium including instructions for causing a computer to implement a method, the method comprising:

receiving at least one signal indicative of a vehicular lateral acceleration;

receiving at least one signal indicative of a vehicular velocity;

providing a plurality of yaw rate estimation functions;

selecting a first yaw rate estimation function of said plurality of yaw rate estimation functions in response to at least one of said received signals; and

estimating a first estimated yaw rate in accordance with the selected said first yaw rate estimation function and at least one of said received signals.

16. A computer data signal for estimating yaw rate of a vehicle, the computer data signal comprising code configured to cause a processor to implement a method, the method comprising:

receiving at least one signal indicative of a vehicular lateral acceleration;

receiving at least one signal indicative of a vehicular velocity;

providing a plurality of yaw rate estimation functions;

selecting a first yaw rate estimation function of said plurality of yaw rate estimation functions in response to at least one of said received signals; and

estimating a first estimated yaw rate in accordance with the selected said first yaw rate estimation function and at least one of said received signals.

17. A controller for providing an estimated yaw rate algorithm for a vehicle, the controller comprising:

means for providing a plurality of signals indicative of an estimated yaw rate;

means for correlating at least a first of the provided signals to determine if it is within a threshold with respect to an actual measured yaw rate signal from a yaw rate sensor;

means for correlating at least a second of the provided signals to determine if it is within the threshold with respect to the actual measured yaw rate signal from a yaw rate sensor; and

means for ignoring at least one of said first signal and said second signal if at least one of said first signal and said second signal is invalid.