METHOD FOR STEERING GEAR-STEERING WHEEL POSITION SYNC IN A STEER-BY-WIRE VEHICLE WITH A CORRESPONDING STEERING WHEEL ARCHITECTURE

Description

Technical field

[0001] The invention relates to a method for steering gear-steering wheel position synchronization in a steer-by-wire vehicle. This vehicle can be a motor vehicle, but also other types of land, air, or watercraft. It has a steering wheel mechanically decoupled from the steering gear and a force-feedback actuator for artificially generating a hand torque, which, during manual steering by the driver, provides feedback from the steering gear to the steering wheel. Position synchronization of the steering wheel with the steering gear (i.e., with the current position of the steered wheels in the case of a motor vehicle) is required in such a vehicle, for example, when steering is handed back to the driver after an automated driving or parking mode in which the steering wheel angle position has lost its reference to the steering gear, for instance, because the steering wheel was stationary. Technical background

[0002] Currently, most motor vehicles have a clock spring that establishes the electrical connection between a stationary steering column module and the rotating steering wheel. The clock spring enables, for example, communication with the multifunction buttons on the steering wheel, detection of horn activation, and the electrical power supply for various electrical components integrated into the steering wheel, such as the illumination or backlighting of the steering wheel buttons, the steering wheel heating, the airbag inflator built into the steering wheel, or a steering wheel designed as a capacitive sensor for hands-off detection.

[0003] In conventional motor vehicles, the steering wheel is usually mechanically connected to a steering gear for the steered wheels, for example via a steering shaft fixed to the steering wheel, an intermediate steering shaft connected to it via a universal joint, and a pinion with the rack, which transmits the steering wheel position to the tie rods of the wheels. In this vehicle design, the clock spring is protected from over-rotation and breakage by a mechanical end stop in the steering gear (in this case, the rack) that prevents the steering wheel movement at a certain angle.

[0004] So-called steer-by-wire steering systems are known for vehicles that could be used in mass production in the automotive sector in the future. These systems have no mechanical connection between the steering wheel and the steering gear or the steered wheels. The steering torque, which transmits feedback from the road and tires to the steering wheel, is artificially generated in steer-by-wire vehicles by means of an electric drive unit called a force feedback actuator (FFA).

[0005] In steer-by-wire vehicles, if wireless energy and signal transmission is established between the stationary vehicle structure (such as a steering column module) and the rotating driver interface (steering wheel), the clock spring can be omitted, as is known, for example, from DE 102 58 871 A1. This also eliminates the need for a non-oversteerable end stop and the requirement to allow only a fixed number of steering wheel rotations before the clock spring would break.

[0006] In another known approach, a clock spring is not needed at all because the parts of the steering wheel that require a power supply and communicate with the rest of the vehicle remain stationary (in the non-rotating center of the steering wheel). Synchronization of the steering wheel and steered wheels' positions is also unnecessary in this case, provided the rotating steering wheel rim is completely rotationally symmetrical. However, this requires the development and manufacture of a novel steering wheel architecture. A further disadvantage is that this approach does not allow for buttons / controls that rotate with the steering wheel. This means that the position of the driver's hand relative to the steering wheel buttons changes with every steering movement. Rotating buttons, on the other hand, would ensure that they are always within easy reach of the thumb.

[0007] For example, DE 10 2017 220 158 A1 proposes, for example, that the steering wheel position synchronization during the transition of a steer-by-wire vehicle from automated driving to non-automated driving be achieved either by adjusting the steering wheel to the current wheel angle of the vehicle or, conversely, by adjusting the wheel angle and the actual steering actuator position to the current steering wheel angle.

[0008] The publication DE 103 31 700A1 discloses a steer-by-wire system in a steering system of a vehicle.The steer-by-wire system comprises: a steering wheel angle sensor configured to determine the angular position of a steering wheel; a torque drive configured to apply a feedback torque to the steering wheel; and a controller that receives a deflection angle of the wheel on the road and further cooperates with the steering wheel angle sensor to determine a steering wheel angle; wherein the controller corrects the position of the steering wheel relative to the angle of the wheel on the road by calculating a corrected steering wheel angle relative to at least one angle of the wheel on the road and actuates the torque feedback drive to position the steering wheel in the corrected steering wheel angle position; and wherein the controller determines a minimum angular deflection by which the steering wheel is turned into the corrected steering wheel angle position.

[0009] The object of the present invention is to provide an alternative or improved method for steering gear-steering wheel position synchronization in a steer-by-wire vehicle, in particular for wheel-steering wheel position synchronization in a motor vehicle. The invention is directed in particular to a corresponding steering wheel architecture and, among other things, to minimizing the modifications required compared to conventional vehicles. Disclosure of the invention

[0010] This problem is solved by a method for steering gear-steering wheel position synchronization in a steer-by-wire vehicle according to claim 1, and by a corresponding computer program, a correspondingly configured control unit, a corresponding steer-by-wire steering system, and a vehicle equipped therewith according to the dependent claims. Further embodiments are specified in the dependent claims. All further features and effects mentioned in the claims and the description of the method also apply to the steering system and the vehicle, and vice versa.

[0011] According to a first aspect, a method for steering gear-steering wheel position synchronization in a steer-by-wire vehicle is provided. The vehicle has a steering wheel that is mechanically decoupled from the steering gear and can be rotated any number of times around its axis. It is therefore assumed, among other things, that no clock spring connects the steering wheel to the stationary vehicle components in which it is mounted, such as a steering column module, etc. To generate a hand torque that provides feedback from the steering gear to the steering wheel during manual steering by the driver, the vehicle has a force-feedback actuator.

[0012] The vehicle in question can be a motor vehicle, but also any other land, air, or water vehicle. A steering gear can be understood as any mechanical device designed to adjust or rotate vehicle components that determine the vehicle's direction of travel. In the case of a motor vehicle, the steering gear causes the desired turning of the vehicle's wheels.

[0013] The process includes the following steps: Step 1:

[0014] Receiving a request for steering gear-steering wheel position synchronization after an automated driving or parking mode in which the steering wheel was not adjusted to the steering gear. This request can be generated automatically in the vehicle, for example, when an imminent handover of steering to the driver is detected or initiated by the vehicle control system. Other scenarios are also possible. Step 2:

[0015] Providing current values ​​of a steering wheel angle position corresponding to the steering gear on the one hand, and an actual steering wheel angle position on the other, and determining the difference between these values. In other words, the actual steering wheel angle position is subtracted from a steering angle position that would correspond to the current position of the steering gear or the steered wheels in manual vehicle control. Step 3:

[0016] Determine the steering wheel rotation required for steering gear-steering wheel position synchronization from the difference determined in step 2, taking into account a periodicity with a predetermined steering angle period corresponding to a full steering wheel rotation or a fraction thereof (i.e., less than a full rotation). In other words, in this step, the predetermined steering angle period is subtracted from the determined difference if, for example, it comprises one or more steering angle periods. The steering wheel rotation thus determined is then executed, for example, before or during the transfer of vehicle steering to the driver.

[0017] Using a motor vehicle as an example, the present invention describes a way to achieve optimized synchronization between the steering wheel position and the actual position of the wheels after prior decoupling by eliminating any mechanical connection between the steering wheel and the steering gear. (Examples of a suitable steering wheel architecture are given below. Everything explained herein using a motor vehicle as an example also applies analogously to any other vehicle.) During autonomous driving or autonomous parking, the steering wheel can be decoupled from the movement of the wheels, for example, to be retracted into the instrument panel. If the driver then has to take over (for example, due to an unforeseen event) while the wheels are turned, the steering wheel must synchronize with the position of the wheels. At large steering angles of the wheels (e.g., when parking, turning, etc.),) This means that even with today's common progressive steering systems, an angle difference of more than one steering wheel turn needs to be bridged.

[0018] One aspect of the present invention is that, without a mechanical connection to the steering gear and without a clock spring requiring protection, the steering wheel no longer needs to be precisely aligned with the position of the wheels, but only periodically over 360°, and even periodically over 360° / n with n-fold rotational symmetry. A further aspect is that, after a prior loss of reference to the current wheel position, the steering wheel rotation for position synchronization can even be performed in the opposite direction to the direction of the turned wheels, as the following embodiment illustrates: According to one embodiment, when determining the steering wheel rotation to be performed for steering gear-steering wheel position synchronization, the predetermined steering angle period is repeatedly subtracted from the aforementioned difference until two possible steering wheel rotations with an amount within the predetermined steering angle period and with opposite directions of rotation are determined.Then, of these two possible steering wheel rotations, the one with the smaller amount is selected. This steering wheel rotation is designated as the one to be executed and is subsequently carried out.

[0019] This results in a maximum steering wheel rotation of 180° required for steering angle synchronization. For example, if the determined angle difference is 365°, by which the steering wheel would have to be rotated to synchronize its position with the turned wheels in conventional systems, the steering wheel in the present method only needs to compensate for an angle difference of 5°. As another example, the wheels are turned to the left, and the steering wheel, after coming to a standstill, exhibits a steering angle difference of 270° relative to this wheel position, which must be synchronized before the driver takes over. In this example, according to the present embodiment, it is sufficient to turn the steering wheel 90° to the right to achieve steering angle synchronization.

[0020] In particular, in the present steering system and method, the steering wheel or a steering shaft rigidly connected to it can be mounted in a steering column module so as to be rotatable any number of times. This steering column module is fixed in the vehicle and can only be adjusted as a whole in one or more directions for individual driver adaptation. One or more electrical or electronic devices can be integrated into the steering wheel, which rotate around its axis together with the steering wheel. The vehicle is designed for wireless energy and / or signal transmission between stationary vehicle components and the electrical / electronic devices integrated into the steering wheel, so that no clock spring is required and the steering wheel can be rotated arbitrarily relative to the steering column module.For this purpose, the vehicle may, for example, have a suitable transformer or other device for wireless power and / or signal transmission between the stationary steering column module and the devices integrated in the steering wheel.

[0021] A suitable transformer can, for example, comprise a primary coil fixed in the steering column module, a secondary coil rigidly connected to the steering wheel shaft, and, optionally to increase efficiency, an integrated iron core made of a soft magnetic material, which is at least partially formed by the steering wheel shaft and / or at least partially rigidly connected to the steering wheel shaft. To convert a DC voltage available on board the vehicle into a transformable AC voltage, an inverter can be provided upstream of the primary coil. To convert the transmitted AC voltage into a usable DC voltage, a rectifier can be provided downstream of the secondary coil.

[0022] The electrical or electronic devices integrated into the steering wheel may, for example, include one or more of the following electrical consumers: a steering wheel heater and / or another high-power consumer with an electrical consumption of at least approximately 30 W, at least approximately 40 W, and in particular at least approximately 50 W; one or more steering wheel buttons for operating the vehicle or an infotainment system integrated therein; a capacitive hands-off detection sensor designed to detect whether the driver's hands are not on the steering wheel; an airbag. In particular, an actuator may be integrated into the steering wheel designed to fold the steering wheel up and down and / or to retract it into an instrument panel when transitioning to automated driving mode.

[0023] According to the invention, the steering wheel essentially possesses n-fold rotational symmetry (also called n-fold rotational or rotational symmetry) about its axis of rotation, such that the aforementioned predetermined steering angle period is 360° / n, where n>1 is an integer. In other words, the steering wheel is designed such that after a rotation about its axis by an angle of 360° / n, it is mapped back onto itself in such a way that no rotation is perceptible from the driver's perspective. Some examples for n=2, 3, 4, and ∞ are shown in the figures.

[0024] The fact that the steering wheel only needs to exhibit the aforementioned steering angle period of 360° / n or the corresponding n-fold rotational symmetry "essentially" means that, in this case, geometrically exact symmetry of the entire steering wheel is not required. What matters is that it is imperceptible to the driver when, after the vehicle has come to a standstill, the steering wheel only follows the steered wheels or the steering gear up to the aforementioned period of 360° / n. In particular, the steering wheel does not need to exhibit any symmetry / periodicity in areas hidden from the driver, such as the rear.Furthermore, in this embodiment, the steering wheel can, for example, have two or more capacitive displays or touchscreens, the design and arrangement of which along the circumference of the steering wheel is symmetrical to achieve the aforementioned periodicity, while the respective display on displays that are located, for example, on the left and / or top from the driver's perspective may be different from those on displays located on the right and / or bottom (cf. . Fig. 3c The different displays on these screens can be swapped and mirrored, for example, during position synchronization with a period of 360° / 2 = 180°, by a correspondingly programmed display control system, in order to provide the driver with the familiar controls in the same position. Therefore, the use of capacitive displays or touchscreens significantly increases the degrees of freedom in the design and arrangement of the multifunction buttons.

[0025] According to the invention, the steering wheel n has essentially identical steering wheel button groups arranged around the steering wheel axis at angular intervals of 360° / n from each other. Each individual steering wheel button group is mirror-symmetrical about two mutually perpendicular axes of symmetry in a steering wheel plane facing the driver. Alternatively or additionally, each steering wheel button group can include at least one capacitive display or touchscreen, the display of which, serving as labeled or asymmetrical steering wheel buttons, is adjusted during steering gear-steering wheel position synchronization depending on the resulting position of the respective display / touchscreen in the steering wheel plane (i.e., position from the driver's perspective left / right and up / down with respect to the steering wheel axis) so that a predetermined orientation for the steering wheel buttons displayed left / right and up / down with respect to the steering wheel axis is maintained.

[0026] For the functionality presented here, the position of the steering wheel and the position of the steering gear or wheels must be known independently of each other. In steer-by-wire vehicles, this is achieved, for example, because both the steering gear and the steering wheel each have an electric motor (such as a servo motor or force feedback actuator) and thus an inherent rotor position sensor with which these positions can be identified. For example, in the present method, the current value of the actual steering angle position of the steering wheel can be provided by a rotor position sensor of the force feedback actuator, while alternatively or additionally, the current value of the steering angle position corresponding to the steering gear can be provided by a rotor position sensor of a servo motor used in the steering gear for (wheel) steering.

[0027] According to a further aspect, a computer program is provided comprising instructions which, when executed in a control unit, cause the control unit to execute the method of the type set forth herein. According to a further aspect, a control unit is provided which is configured to automatically execute the method according to any one of the preceding claims.

[0028] According to another aspect, a steer-by-wire steering system is provided for a vehicle, in particular a motor vehicle, which steering system includes the following: A steering column module designed for a fixed arrangement in the vehicle and adjustable as a whole in one or more directions for individual adjustment to the driver; a steering gear designed to adjust or rotate vehicle components that determine the direction of travel of the vehicle; a steering wheel shaft mounted in the steering column module with a steering wheel fixed to it in a rotationally fixed manner, the rotation of which is mechanically decoupled from both the steering gear and the steering column module, so that the steering wheel can be rotated any number of times about its axis (i.e., the axis of the steering wheel shaft); a force-feedback actuator designed to generate a hand torque which provides feedback from the steering gear to the steering wheel; and a control unit of the type described herein.

[0029] In particular, the steering wheel can have the steering wheel architecture described above, below, in the claims and in the figures. Furthermore, as mentioned above, the steering system can include a suitable transformer or other device for wireless power and / or signal transmission between the stationary steering column module and electrical and electronic components integrated into the steering wheel.

[0030] According to a further aspect, a vehicle, in particular a motor vehicle, is provided. The vehicle comprises a driver's seat and an instrument panel arranged in front of it, as well as a steer-by-wire steering system of the type described herein, the steering column module of which is fixed in the area of ​​the instrument panel. In particular, the steering column module as a whole can be adjustable for individual adaptation to a driver, for example in the axial direction of the steering wheel shaft to adapt the steering wheel to the driver's seating position in a longitudinal direction of the vehicle, and / or in the vertical direction of the vehicle to adapt to the seat height and size of the driver.

[0031] Overall, the method and steering system presented here significantly simplifies steering wheel position synchronization in certain situations after prior decoupling of the steering wheel movement from the steering gear. As the figures show, the current steering wheel architecture requires no modification at all for n=1 and only minimal adjustments for n=2. Brief description of the drawings

[0032] The aspects, embodiments, and configurations of the invention described above are explained in more detail below with reference to the examples shown in the accompanying drawings. The drawings are purely schematic and are not to be understood as being to scale. Identical or corresponding elements bear the same reference numerals in the drawings. They show: Figure 1 shows an embodiment of a motor vehicle with a steer-by-wire steering system configured to perform a method of the type described herein, in a side longitudinal section; Figure 2 shows a comparison of different possibilities for n-fold rotational symmetry of a steering wheel in a steer-by-wire steering system made of Fig. 1 , in top view of the steering wheel from the driver's perspective; Figures 3a-3c show different examples of a steering wheel architecture with 2-fold rotational symmetry in a steer-by-wire steering system. Fig. 1 , in a top view of the steering wheel from the driver's perspective; and Figure 4 an example of a steering wheel architecture with 4-fold rotational symmetry in a steer-by-wire steering system made of Fig. 1 , a top view of the steering wheel from the driver's perspective. Description of embodiments

[0033] Fig. 1 Figure 1 shows a highly simplified schematic longitudinal section illustrating the basic arrangement of various components of a steer-by-wire steering system 1 of the type described herein in a vehicle 2 (also referred to as a steer-by-wire vehicle) of the type described herein, which in this example is a motor vehicle. The vehicle 2 comprises a driver's seat 3 and an instrument panel 4 arranged in front of it, in the area of ​​which, opposite the driver's seat 3, the steering system 1 is fixed.

[0034] The steering system 1 comprises a steering column module 5, which is designed for a fixed installation in the vehicle 2, but can be adjusted as a whole in one or more directions for individual driver adaptation. The steering system 1 further comprises a Fig. 1 The steering gear 6, shown only schematically, is designed to rotate the vehicle wheels 7 in order to change the direction of travel of the vehicle 2. A steering wheel shaft 8, with a steering wheel 9 fixed to it for manual steering of the vehicle 2 by the driver, is mounted in the steering column module 5. The rotational movement of the steering wheel 9 is mechanically decoupled from both the steering gear 6 and the steering column module 5, so that the steering wheel 9 can be rotated any number of times about its axis (i.e., the axis of the steering wheel shaft 8). A force-feedback actuator M is provided to generate a hand torque, which provides feedback from the steering gear 6 to the steering wheel 9.

[0035] The steering system 1 further comprises a control unit 10, which is configured for the automated execution of a procedure of the type described herein. As described in detail above, this procedure serves to synchronize the steering gear and steering wheel positions after an automated driving or parking regime in which the steering wheel was not adjusted to the steered vehicle wheels 7. For this purpose, the control unit 10 is provided with current values ​​from suitable vehicle components (such as angle sensors of a servo motor installed in the steering gear and the force feedback actuator M), either continuously or only upon a synchronization request. These values ​​represent, on the one hand, the steering angle position of the steering wheel 9 corresponding to the current wheel position, and on the other hand, the actual steering angle position of the steering wheel 9.The latter value is subtracted from the former value, and from the difference thus determined, the steering wheel rotation to be performed for synchronization is determined according to the invention with a periodicity corresponding to a predetermined steering angle period, which corresponds to a full steering wheel rotation or less. Subsequently, the steering wheel rotation of the steering wheel 9 determined in this way is executed so that the steering can, for example, be handed back to the driver.

[0036] Figur 2 shows a comparison of some different possibilities (n=1, 2, 4, 3 and ∞) for an n-fold rotational symmetry of the steering wheel 9 of the steer-by-wire steering system 1 from Fig. 1 , in a top view of the steering wheel 9 from the driver's perspective (i.e., in the steering wheel plane facing the driver). As in Fig. 2 As shown in the diagram, the steering wheel 9 can be constructed in its driver-facing plane with respect to one, two, three, or infinitely many axes of symmetry A1, A2, A3..., which corresponds to the aforementioned predetermined steering angle period of 360° / 2 = 180°, 360° / 3 = 120°, 360° / 4 = 90°, or 360° / ∞ = 0°. According to the present method, when synchronizing its position with the previously independently steered vehicle wheels 7, the steering wheel 9 only needs to be adjusted by an angle that lies within the respective predetermined steering angle period = 360° / n. Thus, when n = 1, no more than one full steering wheel rotation is required, while when n = ∞, no steering wheel rotation is necessary for synchronization. In the latter case, for example, it would be possible to completely dispense with multifunction buttons as operating elements and to use, for example, a capacitively designed steering wheel 9, which can also be extended with gesture control.

[0037] How Fig. 2 This shows that unconventional steering wheel designs with odd-numbered rotational symmetry, such as n=3, are also possible because the driver of highly automated vehicles does not constantly hold the steering wheel 9, and ergonomic considerations can therefore be re-evaluated in relation to design considerations. However, a conventional steering wheel architecture (n=1, i.e., no symmetry) is also possible.

[0038] Figuren 3a bis 3c Figure 1 shows some examples of possible arrangements of steering wheel buttons 11 and similar control elements in the steering wheel 9 for n=2, i.e., 2-fold rotational symmetry, which can be particularly advantageous because only minor modifications to the current steering wheel architecture are required. The steering wheel plane facing the driver is always shown. In these examples, the steering wheel 9 has two webs 12 arranged periodically by 180°, which connect a steering wheel rim 13 to the steering wheel shaft 8 or a steering wheel hub. Optionally, a central area 14, fixed relative to the vehicle 2, can be provided radially within the steering wheel hub. This area can house electrical / electronic devices such as airbags, horns, etc., or important symbols or information that do not rotate when the steering wheel 9 is turned.

[0039] In Fig. 3a-3c The steering wheel 9 has two identical or similarly designed steering wheel button groups 15, which are arranged on the respective bridge 12 and have several steering wheel buttons 11 or similar control elements. Fig. 3a und 3b The steering wheel buttons 11 within each group 15 are symmetrically designed around two mutually perpendicular axes of symmetry A4, A5, so that the driver has the same operation available when the steering wheel 9, after its position synchronization within the steering angle period 360° / 2=180°, is "upside down" compared to the conventional steering wheel position. Fig. 3a A round steering wheel (9) is shown as a purely exemplary example. Fig. 3b A rectangular steering wheel 9 is shown, which otherwise has the same properties as a round steering wheel 9. Fig. 3a It may be possible to have a rectangular steering wheel 9, for example, but it may be better to position it in the instrument panel 4.

[0040] The steering wheel 9 of the Fig. 3c differs from that of the Fig. 3a This is achieved simply by using a capacitive display instead of individual steering wheel buttons 11. The display aligns itself accordingly during position synchronization so that the driver sees the same information again after a rotation of the predetermined steering angle period (180°). In this example, different display and control elements can therefore be shown on the otherwise identical and symmetrical displays on the left and right, as shown in the Fig. 3c illustrated by an example.

[0041] The steering wheel 9 of the Fig. 4 differs from that of the Fig. 3a This is only because the predetermined steering angle period is halved again, so instead of 360° / 2=180° it is now 360° / 4=90°. Accordingly, the number of bridges is 12 and the number of steering wheel button groups is 15. Fig. 3a They have been doubled, and these are arranged symmetrically at 90° intervals around the steering wheel axis. This also applies to... Fig. 3a The same principles apply here as well. Reference symbol list

[0042] 1. Steering system, also called steer-by-wire steering system 2. Vehicle, also called steer-by-wire vehicle 3. Driver's seat 4. Instrument panel 5. Steering column module 6. Steering gear 7. Vehicle wheels, also simply called wheels 8. Steering wheel shaft 9. Steering wheel 10. Control unit 11. Steering wheel buttons 12. Guides 13. Steering wheel rim 14. Fixed central section 15. Steering wheel button group M. Force feedback actuator Ai.i-te Axis of symmetry

Claims

1. Method for steering gear-steering wheel position synchronization in a steer-by-wire vehicle (2) having a steering wheel (9) which is mechanically decoupled from a steering gear (6) and which can be rotated any number of times about its axis, and having a force feedback actuator (M) which is configured to generate a hand torque which provides feedback from the steering gear (6) to the steering wheel (9), comprising the steps of: - receiving a request for steering gear-steering wheel position synchronization according to an automated driving or parking regime in which the steering wheel (9) was not adjusted to the steering gear (6); - providing current values of a steering angle position of the steering wheel (9) corresponding to the steering gear (6) on the one hand and an actual steering angle position of the steering wheel (9) on the other hand and ascertaining a difference between these values; - determining a steering wheel rotation to be performed for the steering gear-steering wheel position synchronization from the ascertained difference, taking into account a predetermined steering angle period which corresponds to a full steering wheel rotation or less; and - performing the steering wheel rotation determined in this way, characterized in that the steering wheel (9) has substantially n-fold rotational symmetry about its axis of rotation such that the predetermined steering angle period is 360° / n, where n>1 is an integer, the steering wheel (9) having a number of n identical steering wheel button groups (15) which are arranged at an angular distance of 360° / n from one other about the steering wheel axis; and each of these steering wheel button groups (15) is mirror-symmetrical about two mutually perpendicular axes of symmetry (A1, A2, A3, A4, ...) in a steering wheel plane facing the driver and / or comprises at least one capacitive display or touchscreen, the display of which, serving as labeled or asymmetrical steering wheel buttons (11), is adapted during the steering gear-steering wheel position synchronization on the basis of the resulting position of the relevant display / touchscreen in the steering wheel plane, so that a predetermined orientation for steering wheel buttons (11) displayed as left / right and up / down with respect to the steering wheel axis is maintained.

2. Method according to claim 1, wherein when determining the steering wheel rotation to be performed for the steering gear-steering wheel position synchronization, - the predetermined steering angle period is subtracted from the ascertained difference repeatedly until two possible steering wheel rotations with an amount within the predetermined steering angle period and with different directions of rotation are ascertained; and - of these two possible steering wheel rotations, the one with the smallest amount is determined as the steering wheel rotation to be performed.

3. Method according to claim 1 or claim 2, wherein - the steering wheel (9) or a steering wheel shaft (8) connected thereto for conjoint rotation is mounted, so as to be rotatable any number of times, in a steering column module (5) which is fixed in the vehicle (2) and, if necessary, can be adjusted as a whole in one or more directions for individual adaptation to a driver; - at least one electrical or electronic device is integrated into the steering wheel (9); and - the vehicle (2) is designed for wireless power and / or signal transmission between fixed vehicle components and the at least one device integrated into the steering wheel (9), in particular in that the vehicle (2) has a transformer or other apparatus for wireless power and / or signal transmission between the fixed steering column module (5) and the at least one device integrated into the steering wheel (9).

4. Method according to claim 3, wherein the at least one electrical or electronic device comprises one or more of the following electrical consumers: - a steering wheel heater and / or another large consumer having an electrical consumption of at least approximately 30 W, preferably at least approximately 40 W, particularly preferably at least approximately 50 W; - one or more steering wheel buttons (11) for operating the vehicle (2) or an infotainment system integrated therein; - a capacitive hands-off detection sensor which is designed to detect whether the driver's hands are not on the steering wheel (9); - an airbag; - an actuator which is designed to fold and unfold the steering wheel (9).

5. Method according to any of the preceding claims, wherein - the current value of the actual steering angle position of the steering wheel (9) is provided by a rotor position sensor of the force feedback actuator (M); and / or - the current value of the steering angle position of the steering wheel (9) corresponding to the steering gear (6) is provided by a rotor position sensor of a servo motor which is used in the steering gear (6) for steering (wheels).

6. Computer program comprising commands which, when the computer program is performed in a control unit (10), cause the control unit to perform the method according to any of the preceding claims.

7. Control unit (10) which is designed to automatically perform the method according to any of claims 1 to 5.

8. Steer-by-wire steering system (1) for a vehicle (2), in particular a motor vehicle, comprising: - a steering column module (5) which is designed to be fixed in the vehicle (2) and can be adjusted as a whole in one or more directions for individual adaptation to the driver; - a steering gear (6) which is designed to adjust or rotate vehicle components which determine the direction of movement of the vehicle (2); - a steering wheel shaft (8) which is mounted in the steering column module (6) and has a steering wheel (9) which is attached thereto for conjoint rotation and of which the rotational movement is mechanically decoupled from both the steering gear (6) and the steering column module (5); - a force feedback actuator (M) which is designed to generate a hand torque which provides feedback from the steering gear (6) to the steering wheel (9); and - a control unit (10) according to claim 7, - wherein the steering wheel (9) has substantially n-fold rotational symmetry about its axis of rotation such that the predetermined steering angle period is 360° / n, where n>1 is an integer, wherein - the steering wheel (9) has a number of n identical steering wheel button groups (15) which are arranged at an angular distance of 360° / n from one other about the steering wheel axis; and - each of these steering wheel button groups (15) is mirror-symmetrical about two mutually perpendicular axes of symmetry (A1, A2, A3, A4, ...) in a steering wheel plane facing the driver and / or comprises at least one capacitive display or touchscreen, the display of which, serving as labeled or asymmetrical steering wheel buttons (11), is adapted during the steering gear-steering wheel position synchronization on the basis of the resulting position of the relevant display / touchscreen in the steering wheel plane, so that a predetermined orientation for steering wheel buttons (11) displayed as left / right and up / down with respect to the steering wheel axis is maintained.

9. Vehicle (2), in particular a motor vehicle, comprising: - a driver's seat (3) and an instrument panel (4) arranged in front of it; - a steer-by-wire steering system (1) according to claim 8, the steering column module (5) of which is secured in the region of the instrument panel (4); - wherein the steering column module (5) can preferably be adjusted, for individual adaptation to a driver, as a whole in the axial direction of the steering wheel shaft (8) to adapt the steering wheel (9) to the driver's seating position in a longitudinal direction of the vehicle (2), and / or in the vertical direction of the vehicle (2) to adapt to the seat height and the height of the driver.