DETERMINING A STEERING ANGLE FOR AN AUTOMOBILE APPLICATION

Abstract

A method to operate a motor vehicle having a number of wheels is described. The method determines a steering angle for an automotive application. A steering angle is estimated using a yaw rate , a revolution rate of at least one wheel, a wheelbase L and a characteristic speed of the vehicle v.sub.ch based on a single-track model. Preferably, the steering angle is calculated using the yaw rate , the selected gear i, the wheelbase L, the speed v and the characteristic speed of the vehicle v.sub.ch according to the formula =[*i*L*(1+v.sup.2/v.sub.ch.sup.2)]/v. An application, such as adaptive light control during turns, that requires knowledge of the steering angle of the motor vehicle is carried out based on an estimated steering angle.

Claims

1. A method to operate a motor vehicle comprising: estimating a steering angle using a yaw rate, a revolution rate of at least one wheel, a wheelbase and a characteristic speed of the vehicle based on a single-track model; and applying the steering angle in an adaptive light control system such that an orientation of a head light corresponds to the steering angle.

2. The method as claimed in claim 1, wherein estimating the steering angle uses a steering transmission ratio.

3. The method as claimed in claim 1, wherein estimating the steering angle calculates the steering angle using the yaw rate, a selected gear, the wheelbase, a speed and the characteristic speed of the vehicle.

4. The method as claimed in claim 1 further comprising determining a steering center, and calculating an absolute steering angle using a relative steering angle and a steering center offset calculated from the steering center.

5. The method as claimed in claim 4 further comprising using a sensor to detect the yaw rate and a sensor that detects the revolution rate of the at least one wheel and a sensor that detects the relative steering angle.

6. An adaptive light control apparatus for a vehicle comprising: a sensor suite that determines a yaw rate and a revolution rate of a wheel; and a processor configured to, in response to a calculation of a steering angle using the yaw rate, the revolution rate, a wheelbase and a characteristic speed of the vehicle based on a single-track model, change an orientation of a head light such that the orientation corresponds to the steering angle.

7. The adaptive light control apparatus as claimed in claim 6, wherein the processor is configured to calculate a relative steering angle and determine a steering center offset.

8. The adaptive light control apparatus as claimed in claim 6, wherein the processor is configured to calculate a steering center.

9. A vehicle comprising: a processor configured to, in response to a calculation of a steering angle using a yaw rate, a revolution rate, a wheelbase and a characteristic speed of the vehicle based on a single-track model via data from a sensor suite, change an orientation of a light such that the orientation corresponds to the steering angle.

10. The vehicle as claimed in claim 9, wherein the processor is configured to calculate the steering angle with a steering transmission ratio.

11. The vehicle as claimed in claim 9, wherein the processor is configured to calculate the steering angle with the yaw rate, a selected gear, the wheelbase, a speed and the characteristic speed of the vehicle.

12. The vehicle as claimed in claim 9, wherein the processor is configured to calculate a steering center, and an absolute steering angle using a relative steering angle and a steering center offset calculated from the steering center.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] FIG. 1 shows, schematically, logic according to the disclosure in a flow chart;

[0019] FIG. 2 shows, schematically, an apparatus according to the disclosure to estimate a steering angle of a motor vehicle; and

[0020] FIG. 3 shows schematically a motor vehicle according to the disclosure.

DETAILED DESCRIPTION

[0021] As required, detailed embodiments of the present disclosure are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the disclosure that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present disclosure.

[0022] FIG. 1 shows, schematically, logic for a method or device according to the disclosure in the form of a flow chart. In step 10, the vehicle starts to move. In step 11, a check is carried out as to whether a steering center is available. If a steering center is not available at 11, on the one hand, in step 12, a calculation or calibration of the steering center is thus begun. In step 13, a steering angle is determined or calculated based on a single-track model. For this purpose, sensors 15 for input values of a yaw rate and a revolution rate of at least one wheel are made available to the calculation of the steering center in step 14. Furthermore, as vehicle-specific values 16, a wheelbase L, a characteristic speed v.sub.ch, preferably as a function of a self-steering gradient, and, if necessary, a steering ratio are provided for the calculation of the steering center in step 14.

[0023] In the context of the calculation of the steering center in step 14, a steering angle can be calculated according to the formula

=[*i*L*(1+v.sup.2/v.sub.ch.sup.2)]/v,

wherein i denotes a selected gear and v denotes a speed of the vehicle. The speed v can for example be derived from the revolution rate.

[0024] Based on an absolute steering angle determined from the calculation of the steering center in step 14, in step 17 an application based on the steering angle is started and carried out. This can be adaptive light direction control or headlight control, for example.

[0025] If the steering center is available in step 11, or is available following a return from step 12 to step 11 following a calculation of the steering center, then the absolute steering angle value is calculated in step 18. For this purpose, a relative steering angle and a steering center offset are used as input data 19. Based on the absolute steering angle thus calculated in step 18, the already described application for adaptive light, or headlight control can be started and carried out or continued in step 17.

[0026] FIG. 2 shows schematically an apparatus according to the disclosure 20 to estimate the steering angle of a motor vehicle 30. The apparatus 20 comprises a sensor 21 that determines the yaw rate and a device 22 that determines the revolution rate of at least one wheel of the motor vehicle 30. Said device is designed to carry out a method that is described above, in particular a method described in connection with FIG. 1. For this, the apparatus 20 shown in FIG. 2 comprises a device 26 that estimates or calculates the steering angle.

[0027] The apparatus 20 can optionally comprise a device 23 that determines the relative steering angle and/or a device 24 that determines the steering center offset and/or a device 25 that calculates the steering center. The apparatus according to the disclosure 20 is preferably an apparatus for adaptive light control or light direction control.

[0028] FIG. 3 shows schematically a motor vehicle according to the disclosure. The motor vehicle according to the disclosure 30 comprises a number of wheels 31, a steering mechanism 32, headlights 33 and an apparatus according to the disclosure 20 that is described above. The apparatus 20 is designed for carrying out the described method, preferably the method described in connection with the logic of FIG. 1. The motor vehicle preferably comprises adaptive headlight control, which can be applied by using the described method and logic shown in FIG. 1.

[0029] While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms of the disclosure. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the disclosure. Additionally, the features of various implementing embodiments may be combined to form further embodiments of the disclosure.