Vehicle steering angle position determination method
First Claim
1. A method of estimating the true steering angle value of a vehicle, said method comprising:
- obtaining a relative position steering angle value;
obtaining a plurality of vehicle operating parameter values;
calculating a plurality of estimated values, each of said values being a function of one of a plurality of different vehicle models, each of said vehicle models including at least one variable corresponding to one of said plurality of vehicle operating parameter values;
estimating a steering angle offset value as a function of a weighted average of said plurality of estimated values; and
estimating the true steering angle value of the vehicle as a function of said relative position steering angle value and said steering angle offset value.
1 Assignment
0 Petitions
Accused Products
Abstract
A system for calculating the actual steering angle position based upon signals received from a relative position steering angle sensor and other vehicle sensors. The system involves calculating a steering angle value based upon a plurality of vehicle models and then weighting and combining the values to determine a steering angle reference value which is used to calculate an offset value which can be applied to the relative position steering angle sensor value to provide a true steering angle value. The vehicle models include a yaw rate model, a lateral acceleration model, a front axle model and a rear axle model. An uncertainty factor is calculated and used to filter the offset value. The data used to determine the offset value may be obtained when the vehicle is driving forward and also when driving rearwardly and relatively straight.
82 Citations
22 Claims
-
1. A method of estimating the true steering angle value of a vehicle, said method comprising:
-
obtaining a relative position steering angle value;
obtaining a plurality of vehicle operating parameter values;
calculating a plurality of estimated values, each of said values being a function of one of a plurality of different vehicle models, each of said vehicle models including at least one variable corresponding to one of said plurality of vehicle operating parameter values;
estimating a steering angle offset value as a function of a weighted average of said plurality of estimated values; and
estimating the true steering angle value of the vehicle as a function of said relative position steering angle value and said steering angle offset value. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
defining a mode value of said method, said mode value being a function of the number of calculated steering angle offset value estimates; and
communicating said mode value and all changes in said mode value to a controller.
-
-
14. A method of estimating the true steering angle value of a vehicle, said method comprising:
-
obtaining a relative position steering angle value;
obtaining at least one vehicle operating parameter value;
calculating at least one estimated value, said estimated value being a function of a vehicle model including at least one variable corresponding to said at least one vehicle operating parameter value;
estimating a steering angle offset value as a function of said estimated value;
estimating the true steering angle value of the vehicle as a function of said relative position steering angle value and said steering angle offset value; and
wherein prior to estimating the actual steering angle value said method includes;
selecting data acceptable for use in estimating said steering angle offset value, wherein data acceptable for use includes data obtained when the sign of a sensor-measured yaw rate of the vehicle (vGimeas) is the same as a model-based yaw rate (vGiVr) calculated using front and rear axle operating parameters; and
data obtained when the sign of vGimeas is opposite the sign of vGiVr when relatively straight rearward driving is detected.- View Dependent Claims (15, 16)
-
-
17. A method of estimating the true steering angle value of a vehicle, said method comprising:
-
(a) obtaining a relative position steering angle value;
(b) obtaining at least one vehicle operating parameter value;
(c) calculating at least one estimated value, said estimated value being a function of a vehicle model including at least one variable corresponding to said at least one vehicle operating parameter value;
(d) estimating a steering angle offset value as a function of said estimated value;
(e) estimating the true steering angle value of the vehicle as a function of said relative position steering angle value and said steering angle offset value;
(f) repeating steps (a) through (e) and assigning a Percent Certainty value to each estimated true steering angle value, said Percent Certainty value being a function of the number of repetitions of steps (a) through (e); and
(g) communicating said estimated true steering angle value and said Percent Certainty value to a controller. - View Dependent Claims (18, 19, 20, 21, 22)
defining a mode value of said method, said mode value being a function of the number of repetitions of steps (a) through (e); and
communicating said mode value and all changes in said mode value to a controller.
-
Specification