Data processing: vehicles – navigation – and relative location – Vehicle control – guidance – operation – or indication
Reexamination Certificate
1998-08-10
2001-03-06
Cuchlinski, Jr., William A. (Department: 3661)
Data processing: vehicles, navigation, and relative location
Vehicle control, guidance, operation, or indication
C701S072000, C701S044000, C303S146000, C303S140000, C180S412000, C180S413000, C180S410000, C180S421000
Reexamination Certificate
active
06198988
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to a method of detecting an erroneous signal. More particularly, the present invention relates to a method for detecting an erroneous direction of travel signal as used in a motor vehicle yaw control system.
2. Disclosure Information
Automotive vehicles with braking systems which respond to vehicle conditions as well as driver input have been produced. For example, when a particular yaw rate that is desired by a driver's steering wheel operation is not producing an adequate yaw rate, the braking system of the vehicle may compensate by altering a particular wheel's speed. However, when a vehicle is traveling reverse its normal operation direction, this response may not be appropriate. For this reason, it is necessary to provide the brake system with some indication of vehicle travel direction, e.g. forward or reverse. Further, it would be desirable to provide a system capable of robustly detecting an erroneous travel direction indication.
U.S. Pat. No. 5,686,662 ('662) addresses this problem by gathering two estimates of yaw rate, one estimate from the speeds of the left and right undriven wheels, and the other estimate from vehicle speed, steering wheel position, and lateral acceleration. A yaw rate is then measured using a yaw rate sensor. Finally a reverse travel condition is indicated if the signs of the first two estimates are opposite that of the measured yaw rate. However, under various operating conditions, the system described in '662 may have robustness difficulties. For instance, the correction coefficient, &ohgr;
c
, is unknown at vehicle start-up, and thus for an indeterminate period of initial vehicle operation, one of the two estimates of vehicle yaw rate can not be independently determined in a manner which will allow robust detection of a reverse travel direction. Also, the '662 patent assumes that a difference in signs between the estimates and the measured yaw rate indicate a reverse travel direction, whereas such an instance could occur due to a yaw sensor fault.
It would be desirable to provide a method for indicating an erroneous travel direction that is robust to faults and disturbances of the wheel speed sensor, steering wheel sensor, and yaw rate sensor, operative from the moment of vehicle start-up.
SUMMARY OF THE INVENTION
There is disclosed herein a method for detecting an erroneous direction of travel signal for use in actively controlling the yaw of a motor vehicle. In order to detect an erroneous travel direction, the present invention first establishes two yaw rate estimates using different data to calculate each estimate. The present invention then calculates the difference between these two estimates, and halts the analysis if this difference is greater than a predetermined threshold. However, if this difference is less than a predetermined threshold, the present invention continues by calculating the difference between the measured yaw rate of the yaw rate sensor and one of the yaw rate estimates. Finally, if this difference is greater than a predetermined threshold, an erroneous travel direction is indicated. If this difference is less than a predetermined threshold, normal operation is indicated by the present invention, with no erroneous travel direction being indicated.
REFERENCES:
patent: 5261503 (1993-11-01), Yasui
patent: 5267627 (1993-12-01), Frank et al.
patent: 5313389 (1994-05-01), Yasui
patent: 5333058 (1994-07-01), Shiraishi et al.
patent: 5457632 (1995-10-01), Tagawa et al.
patent: 5576957 (1996-11-01), Asanuma et al.
patent: 5617337 (1997-04-01), Eidler et al.
patent: 5642281 (1997-06-01), Ishida et al.
patent: 5686662 (1997-11-01), Tracht et al.
patent: 5694319 (1997-12-01), Suissa et al.
patent: 5707117 (1998-01-01), Hu et al.
patent: 5710705 (1998-01-01), Eckert
patent: 5719790 (1998-02-01), Lohrenz et al.
patent: 5732372 (1998-03-01), Marsden
patent: 5746486 (1998-05-01), Paul et al.
patent: 5799745 (1998-09-01), Fukatani
patent: 5864769 (1999-01-01), Inagaki et al.
patent: 5869753 (1999-02-01), Asanuma et al.
patent: 5931546 (1999-08-01), Nakashima et al.
patent: 5941919 (1999-08-01), Pastor et al.
patent: 5964819 (1999-10-01), Naito
patent: 6085860 (2000-07-01), Hackl et al.
patent: 6092882 (2000-07-01), Matsuno
patent: 4-254259 (1992-09-01), None
Brown Gregory P.
Cuchlinski Jr. William A.
Ford Global Technologies Inc.
Hernandaz Olga
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