Method for operating a steering system, and steering system

Abstract

The invention relates to a method for operating a steering system for a vehicle, said vehicle being capable of being operated in a manual driving mode as well as in an autonomous driving mode, wherein - in a manual driving mode, the steering handle is in an actuatable state in order to manually actuate a steering movement, - in an autonomous driving mode of the vehicle, the steering handle is in a locked, non-actuatable state, and - the vehicle driver initiates a transfer from the manual driving mode to the autonomous driving mode during a drive of the vehicle. At least one plausibility check is carried out during the transition from the actuatable state to the locked state of the steering handle, and if the plausibility check results in that the initiation is not desired by the vehicle driver, the transition from the actuated state to the locked state of the steering handle is canceled.

Description

[0001] Method for operating a steering system and steering system

[0002] The invention relates to a method for operating a steering system according to the preamble of claim 1 and to a steering system for carrying out the method according to the independent claim 8. For the prior art, reference is made, for example, to DE 102 59 684 A1, DE 1 916 652, DE 10 2016 210 622 A1, DE 10 2016 011 461 A1 and US 2018 008 6297 A1.

[0003] As is well known, today's common motor vehicles, especially passenger cars, have a substantially stationary steering column on which a steering wheel is mounted. Particularly in the steering wheel area, in addition to this conventional design of the steering column and steering wheel, other designs of motor vehicle steering handles are conceivable and possible, which are characterized, for example, by increased comfort due to more extensive adjustment options. For example, DE 102 59 684 A1 shows a steering wheel handle for a motor vehicle that is mounted on an arm that can be pivoted about an axis running essentially in the vehicle's longitudinal direction and can be adjusted with this arm.

[0004] Furthermore, a steering wheel is known from the above-mentioned 1 916 652 German document which, in order to increase comfort, more precisely to make it easier for the vehicle occupant to get out of the vehicle, shows a steering wheel which can be folded away, for example, towards the vehicle floor.

[0005] However, the demand for comfort is increasing, particularly in the age of driver assistance systems and autonomous driving. For example, for reasons of comfort and space, it is desirable for autonomous vehicle control to no longer position the steering wheel within the driver's direct reach. Nevertheless, the driver must be able to intervene in the (autonomous) driving process at any time. Such restrictions and transition conditions from manual to autonomous driving represent a technical challenge in the development and design of vehicles and vehicle systems. For example, DE 10 2016 210 622 A1 describes a method for transferring control of a motor vehicle from a first vehicle control system to another vehicle control system.By transferring a vehicle guidance device, which also includes a steering wheel, the vehicle guidance system is switched from a first vehicle guidance system to a second vehicle guidance system. Upon actuation of an actuating device, the vehicle guidance device is moved from a first installation position to at least one second installation position in the vehicle by a translational movement.

[0006] Furthermore, steering systems, such as those shown in US 2018 008 6297 A1, are shifted away from the front of the vehicle during autonomous driving and shifted out again (e.g., toward the dashboard) during manual driving. US 2018 008 6297 A1 shows a steering wheel that can be shifted into the dashboard and includes a display in the steering wheel rim. An airbag module is located behind the display.

[0007] DE 10 2016 011 461 A1 shows a vehicle that can be operated in both autonomous and manual driving modes. The steering handle can be folded for operation of the vehicle in autonomous driving mode, and a display, also located in front of the driver, can be moved toward the front of the vehicle, away from the driver. The driver can thus use the display for entertainment during autonomous driving, while during manual driving the display is pivoted back toward the front of the vehicle and the steering wheel is at least partially extended.

[0008] Numerous embodiments are known in which a steering handle is folded, folded, or moved, allowing the vehicle's interior to be more easily used by the vehicle occupants during autonomous driving. With fully autonomous driving, a transition from a manual to an autonomous driving mode should be possible even while the vehicle is moving. However, there is a risk that, for example, a technical error or incorrect operation by the driver could result in the steering handle being moved and folded accidentally while driving.

[0009] It is therefore an object of the invention to provide a method for operating a steering system which prevents an unwanted transition from a manually operated steering handle to an autonomous steering operation.

[0010] The solution to the problem is achieved by a method having the features of claim 1 and by a steering handle having the features of the independent claim 8. Advantageous developments and further developments are the subject of the subclaims.

[0011] A system for operating a steering system of a vehicle is proposed, wherein the vehicle can be operated in a manual as well as in an autonomous driving mode.

[0012] In an autonomous driving mode, the vehicle, the vehicle control system, or a driver assistance system takes over vehicle control. The driver no longer needs to perform any vehicle control tasks themselves. In a semi-autonomous or highly automated driving mode, individual vehicle control tasks, such as lateral control (i.e., steering), are taken over by suitable driver assistance systems.

[0013] If necessary, for example in critical situations or at the driver's request, the driver or a passenger must or can take over at least some of the control of the vehicle. A change from autonomous to manual mode occurs.

[0014] In manual driving mode, the driver assumes at least partial control of the vehicle. The driver must then assume lateral control of the vehicle. This means they must steer the vehicle themselves using a steering handle. The steering handle is designed to be operable when the vehicle is in manual driving mode.

[0015] An operable state in the sense of this invention means that the steering handle is designed and positioned in the vehicle interior in such a way that a driver is able to operate the steering handle without any problems.

[0016] In an autonomous driving mode of the vehicle, however, the steering handle is in a non-operable, locked state.

[0017] In the context of this invention, a locked state means that the steering handle is positioned or designed in the vehicle in such a way that it cannot be reached by a driver or that it cannot be operated by a vehicle occupant or that an operation has no influence on the driving function.

[0018] The steering handle can be retracted or folded into the vehicle's dashboard, particularly toward the front of the vehicle. Additionally or alternatively, the steering handle can be folded or folded in on itself. It is also possible that the steering handle is mechanically locked in such a way that it can no longer be operated.

[0019] It is further envisaged that a transition from manual to autonomous driving mode while the vehicle is moving is generally initiated by a driver or occupant, or a sufficient indication for automatic transition is detected. For example, such initiation occurs via a corresponding button or switch in the vehicle and / or via a corresponding gesture or movement of the vehicle occupant.

[0020] If a transition from manual to autonomous driving mode is initiated by a driver while the vehicle is moving, the steering handle is changed from an operable to a locked state.

[0021] It is also intended that a plausibility check is performed when or while the steering handle is being moved from an operable to a locked state (i.e., during the transition to the locked state). The plausibility check verifies whether the driver's initiation of the transition from an operable to a locked state of the steering handle was intentional or unintentional. If the plausibility check shows that the transition was intentional (= plausible), the transition to the locked state continues.

[0022] If the plausibility check reveals that the transition was unintentional, for example, due to a system error or incorrect operation, the transition to the locked state is aborted. The steering handle is then returned to its original, operable state. The driver is then prompted to manually operate the steering handle again.

[0023] The plausibility check is preferably carried out at a time when the locked state of the steering handle has not yet been reached and the driver does not have the possibility (even if initially limited) to operate the steering handle and steer the vehicle manually.

[0024] Thus, the proposed plausibility check can advantageously prevent an unintentional locking of the steering handle by the driver at an early stage.

[0025] The plausibility check will preferably use existing physical vehicle variables and / or a steering wheel torque and / or a lateral acceleration of the vehicle and / or a longitudinal acceleration of the vehicle and / or a vehicle speed and / or information from an interior monitoring system of the vehicle and / or a seating position of the driver.

[0026] For example, seat occupancy sensors or an interior camera are used to check whether a driver has already moved to a seat other than the driver's seat or whether they have already left the driver's seat. Leaving the driver's seat, for example, would indicate that the driver has requested autonomous driving mode, and initiating the locked mode seems plausible.

[0027] In a preferred embodiment of the invention, the transition from the operable to the locked state of the steering handle is divided into at least two phases, particularly preferably three phases. A plausibility check is performed after each phase. For the purposes of this invention, the "transition" refers to a spatial transformation of the steering handle from the operable to the locked state. This transformation is particularly in the form of a movement or geometric change of the steering handle.

[0028] With each advancing phase, it becomes more difficult for a vehicle occupant to steer the vehicle manually, i.e. with each phase, the steering handle moves spatially closer to the locked state.

[0029] The first phase, for example, in the case of a steering handle that can be retracted toward the front of the vehicle, represents the initial retraction path of the steering handle toward the front of the vehicle. This initial retraction path is only a few centimeters, for example, in the range of 1-3 cm. The steering handle is retracted slowly toward the front of the vehicle, for example, over 2-5 seconds. After reaching the initial retraction path, an initial plausibility check of the steering handle's retraction movement is performed.

[0030] If the test results in a "plausible" result, the steering handle is retracted a second distance toward the front of the vehicle in the second phase. Once the second distance is reached, the steering handle is in its final position. The second retraction distance is, for example, another 10-15 cm and lasts another 3-6 seconds.

[0031] After reaching the final position (or on the way there), the transformation undergoes a further plausibility check to enable the transition to the third transformation phase. Only after a further check with a "plausible" result does the final, most critical transformation phase begin—in this specific example, the folding or folding of the steering handle, i.e., the final mechanical locking of the steering handle.

[0032] The individual transformation phases must run in a defined order, but can be compressed and / or parallelized as required.

[0033] The steering handle does not necessarily have to be retracted toward the front of the vehicle. Any type of movement or geometric change of the steering handle, including a locked state, is possible. The phased transformation with the subsequent plausibility checks can thus prevent unwanted and erroneous movements of the steering handle.

[0034] In addition to the method, a steering system of a vehicle for carrying out the method according to one of claims 1 to 7 is also proposed.

[0035] In particular, a steer-by-wire steering system is proposed. So-called steer-by-wire steering systems for vehicles are already known in various forms from the state of the art. This differs from conventional steering systems in that the steering of the wheels is completely decoupled from the driver's mechanical steering movement or takes place solely through a purely electronic transmission. The conventional mechanical transmission devices are eliminated; instead, the driver generates data through their steering movement on the so-called steering handle or steering wheel, which is fed into an electronic control unit. This control module evaluates the data and converts it into corresponding steering commands. This then controls the steering gear, which executes the desired steering movement.

[0036] The steering system further comprises the aforementioned steering handle for manually actuating a steering movement in a manual driving mode of the vehicle. In a manual driving mode, the steering handle is in an operable state as described above, while in an autonomous driving mode it is in a locked state. In the locked state, it can no longer be manually actuated by the driver. The steering handle can be, for example, a steering wheel.

[0037] Furthermore, an actuator unit is provided that adjusts or moves the steering handle from the operable to the locked state. The actuator unit, for example a motor, can be electrically and / or mechanically and / or magnetically actuated. Furthermore, an initiation device is provided for manually initiating the manual driving mode by the driver while the vehicle is moving. As already mentioned above, this can be a switch or a button in the vehicle interior. Alternatively or additionally, it is also possible for a gesture or corresponding movement by the driver to represent such initiation.

[0038] In order to carry out a plausibility check, a recording and evaluation unit is also required.

Claims

Patent claims 1. A method for operating a steering system of a vehicle, wherein the vehicle can be operated in a manual as well as in an autonomous driving mode, - wherein in a manual driving mode, a steering handle for manually actuating a steering movement is in an operable state, - wherein the steering handle is in a non-operable, locked state in an autonomous driving mode of the vehicle, - wherein a vehicle driver initiates a transfer from manual to autonomous driving mode while the vehicle is driving, characterized in that at least one plausibility check is carried out during the transition from the operable state to the locked state of the steering handle, wherein if the plausibility check shows that the initiation by the vehicle driver is unintentional, the transition from the actuated to the locked state of the steering handle is aborted.

2. Method according to claim 1, wherein the transition from the operable to the locked state of the steering handle is divided into at least two phases, wherein a plausibility check is carried out after each phase.

3. Method according to claim 1 or 2, wherein the steering handle is extended and / or unfolded in an actuatable state towards the vehicle interior and wherein the steering handle is retracted and / or folded upon initiation of the autonomous driving mode and wherein the steering handle is mechanically locked after complete retraction and / or folding so that it can no longer be actuated by the vehicle driver, wherein at least one plausibility check is carried out before the complete folding and / or retraction and / or before the locking of the steering handle.

4. The method according to claim 2 or 3, wherein the steering handle is partially retracted and / or folded up to a first retraction path and / or folding path upon initiation of the autonomous driving mode in a first phase, wherein a first plausibility check is carried out after reaching the first retraction path and / or folding path.

5. The method according to claim 4, wherein if the first plausibility check was plausible, the steering handle is retracted and / or folded up to a second retraction path in a second phase and a second plausibility check is carried out upon reaching the second retraction path and / or folding path.

6. The method according to claim 1 to 5, wherein a plausibility check is carried out immediately before the steering handle enters a locked state.

7. Method according to one of the preceding claims, wherein the plausibility check uses existing physical vehicle variables and / or a steering wheel torque and / or a lateral acceleration of the vehicle and / or a longitudinal acceleration of the vehicle and / or a vehicle speed and / or information from an interior monitoring system of the vehicle and / or a seating position of the driver.

8. Steering system of a vehicle for carrying out the method according to one of claims 1 to 7, wherein the vehicle is operable in a manual as well as in an autonomous driving mode, comprising A steering handle for manually actuating a steering movement in a manual driving mode of the vehicle, wherein the steering handle is in an actuatable state in a manual driving mode and the steering handle is in a locked state in an autonomous driving mode so that it can no longer be actuated by the vehicle driver; An actuator unit for adjusting the steering handle into an operable and a locked state; An initiation device for manually initiating the autonomous driving mode by the driver while the vehicle is moving; A recording and evaluation unit for recording and evaluating the data from the plausibility check.

9. Steering system according to claim 8, wherein the steering system is a steer-by-wire steering system.

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