Method for operating a fully automatically movable motor vehicle and motor vehicle

Abstract

Method for operating a fully automatically movable motor vehicle (1), comprising a front axle (2) with front wheels (3) steerable by a front axle steering device (6), a rear axle (4) with rear wheels (5) steerable by a rear axle steering device (7), a drive (9) for driving the front wheels (3) and / or the rear wheels (5), and a control device (8), wherein the control device (8) is designed to determine and execute a travel trajectory (10) for a maneuvering maneuver, in particular a parking maneuver, using environmental data (11) describing at least one potential maneuvering area for maneuvering maneuvers, wherein the travel trajectory (10) has a transverse offset section (Q), for the implementation of which the control device (8) carries out the following partial sequences (T) of steps at least once in alternation: In a first subsequence (T), - controlling the front axle steering device (6) and the rear axle steering device (7) to deflect the front wheels (3) and the rear wheels (5) in the same direction by a first steering angle (L) in a first steering direction, - controlling the drive (8) with a first drive direction for moving the motor vehicle (1) along a first route (F), and in a second subsequence (T), - controlling the front axle steering device (6) and the rear axle steering device (7) to deflect the front wheels (3) and the rear wheels (5) in the same direction by a second steering angle (L) in a second steering direction opposite to the first steering direction, and - controlling the drive (9) with a second drive direction opposite to the first drive direction for moving the motor vehicle (1) along a second route (F), characterized by that a target position (Z) of the shunting maneuver is determined by means of the control device (8) from a user input (19) and the environmental data (11), wherein the user input (19) is made as a voice input and describes the target position (Z) with reference to at least one environmental object (27) of the environment of the motor vehicle (1).

Description

[0001] The invention relates to a method for operating a fully automatically movable motor vehicle, comprising a front axle with front wheels steerable by a front-axle steering device, a rear axle with rear wheels steerable by a rear-axle steering device, a drive for driving the front wheels and / or the rear wheels, and a control device. The control device is configured to determine and execute a driving trajectory for a maneuvering maneuver, in particular a parking maneuver, using environmental data describing at least one potential maneuvering area for maneuvering maneuvers. The invention also relates to a motor vehicle.

[0002] In addition to the front wheels steered by a front-axle steering system (front-axle steering), many motor vehicles also have rear wheels steered by a rear-axle steering system (rear-axle steering). The latter is used to improve the vehicle's driving dynamics.

[0003] Rear-axle steering is particularly advantageous when cornering or maneuvering, as it reduces the vehicle's turning circle. This is achieved by steering the front wheels in one direction and the rear wheels in the opposite direction. This allows the front and rear wheels to align on a common circular path, reducing the turning circle and increasing the vehicle's agility.

[0004] For example, DE 10 2010 047 958 A1 describes a one- or two-steering maneuver strategy for the autonomous parking of a motor vehicle, in which rear-axle steering is used to reduce the necessary turning circle of the motor vehicle when parking.

[0005] Ultimately, rear-axle steering is used for maneuvering due to the limited adjustability of the steering angle of the rear wheels, which reduces the turning circle. Maneuvering maneuvers are therefore limited to typical applications that could theoretically be performed without rear-axle steering. Positioning the vehicle in restricted maneuvering areas is therefore only possible to a limited extent with current technology.

[0006] DE 10 2016 121 632 A1 relates to a method for at least semi-autonomously parking a motor vehicle in a parking space. The goal is to achieve the most effective and fastest parking possible. The method describes a parking maneuver of a motor vehicle with steerable front wheels and steerable rear wheels in a parallel parking space, which is measured by environmental sensors of the motor vehicle. A parking trajectory for the parking maneuver is calculated based on the measured data. This parking trajectory comprises at least two sections or steps: a first step, in which the motor vehicle is moved from a starting position to an intermediate position, and a second step, in which it is moved from the intermediate position to an end position. The motor vehicle can be efficiently parked from the intermediate position, even in small parallel parking spaces, by deflecting the front and rear wheels in the same direction.

[0007] DE 39 41 464 A1 relates to a steering system for a car with steerable front and rear wheels, which describes autonomous parking of the car in a parking space. The front and rear wheels are alternately turned in the same direction, with a change in direction occurring simultaneously with the change in wheel angle. Manual actuation of a switching device initiates the autonomous parking process.

[0008] DE 10 2012 200 725 A1 discloses a system and a method for remotely controlling a vehicle, in particular a motor vehicle, in which safety measures and aspects of operating ergonomics are defined, which could become of central importance for series approval of such a system. The system comprises a vehicle and a remote control device, wherein the vehicle comprises a transceiver device configured to exchange signals with the remote control device, and the system is configured to implement various approval-relevant aspects of operating safety of such a system. The motor vehicle and its immediate surroundings can be shown to a user on a display of the remote control in order to set a movement area for the motor vehicle.

[0009] DE 10 2016 221 106 A1 relates to a method for externally controlling an autonomous motor vehicle. The method includes outputting a map section and a position of the autonomous vehicle therein to a user. A user input can indicate a desired driving maneuver. The method includes calculating at least one driving trajectory for the autonomous vehicle based on the user input. Autonomous movement along the driving trajectory can occur after receiving a second user input indicating the user's consent to the driving trajectory.

[0010] The object of the invention is therefore to provide a concept with which the maneuverability of a motor vehicle can be improved, in particular for restricted maneuvering areas.

[0011] The object is achieved by a method having the features of claim 1. It is provided that the travel trajectory has a transverse offset section, for the implementation of which the control device carries out the following partial sequences of steps at least once in alternation: In a first sub-sequence, - controlling the front axle steering device and the rear axle steering device to deflect the front wheels and the rear wheels in the same direction by a first steering angle in a first steering direction, - controlling the drive with a first drive direction to move the motor vehicle along a first route, and in a second subsequence, - controlling the front axle steering device and the rear axle steering device to deflect the front wheels and the rear wheels in the same direction by a second steering angle in a second steering direction opposite to the first steering direction, and - Controlling the drive with a second drive direction opposite to the first drive direction to move the motor vehicle along a second route.

[0012] Furthermore, the invention provides that a target position of the maneuvering maneuver is determined by means of the control device from a user input and the environmental data, wherein the user input is made as a voice input and describes the target position with reference to at least one environmental object of the environment of the motor vehicle.

[0013] All of the aforementioned procedural steps are performed independently by the motor vehicle, specifically by its control system, so that the motor vehicle can be described as moving completely automatically. Therefore, no action by the motor vehicle user is required during the execution of the driving trajectory.

[0014] In the course of the method according to the invention, environmental data relating to the current surroundings of the motor vehicle are first acquired. The environmental data describe a potential maneuvering area for a maneuvering maneuver of the motor vehicle, i.e., an area of ​​the surroundings of the motor vehicle that is available for a maneuvering maneuver. They can be determined using at least one environmental sensor of the motor vehicle, for example, a camera and / or a lidar sensor or the like. Using the at least one environmental sensor, the control device can determine the current position of the motor vehicle, if this is not yet known. This determination can also be performed using a GPS system.

[0015] The control device is preferably configured to detect areas of the motor vehicle's surroundings, described by the environmental data, in which obstacles such as buildings or parked vehicles are located. It can then filter out the area of ​​the surroundings available for a collision-free maneuver of the motor vehicle. Depending on the environmental data and / or the current position of the motor vehicle as well as a desired target position, the control device can thus determine or calculate the travel trajectory for the maneuver. This describes the movement path along which the motor vehicle automatically moves, with the travel trajectory also describing the temporal progression of the movement.

[0016] A basic concept of the invention provides the possibility of transverse offsetting the motor vehicle by using a transverse offset section. The option of transversely offsetting a motor vehicle, which, as will be explained below, requires hardly any space in the longitudinal direction of the motor vehicle, not only makes the specific selection of the driving trajectory more flexible, but also enables the implementation of maneuvering maneuvers that would be impossible or difficult without transverse offsetting options. In other words, situations in which the motor vehicle must not obstruct traffic and in which the maneuvering maneuver must sometimes take place with severely restricted freedom of movement, depending on the parking situation, can be handled more effectively. Generally speaking, it is proposed to implement a type of "crab walk" through the motor vehicle in the smallest possible space through intelligent control of the front and rear axle steering.For this purpose, the wheels of all axles are deflected analogously to one another and the vehicle travels a limited distance in one direction of travel, only to have achieved a total lateral offset to the original position with opposite deflection and travel in the opposite direction of travel, with the same travel distances and steering angles for both directions without any total longitudinal offset.

[0017] To achieve the transverse offset section, i.e. the movement of the motor vehicle perpendicular to its longitudinal direction, the method steps listed above are carried out sequentially. These represent two partial sequences, of which both partial sequences are carried out in a first run of the method according to the invention. The transverse offset section can comprise any number of at least two partial sequences, with the first and second partial sequences always alternating. This means that a first partial sequence is followed by a second partial sequence and a second partial sequence by a first. Termination is possible after both a first and a second partial sequence. An even or an odd number of partial sequences can therefore be provided, depending on the requirements with regard to the transverse offset.Both sub-sequences each comprise two steps, whereby in the first step the wheels of the motor vehicle are deflected in the same direction and in the second step the motor vehicle is moved to achieve a partial transverse offset.

[0018] In the first step of the first sub-sequence, the control device controls both steering devices such that they deflect the front and rear wheels in the same direction by the first steering angle in the first steering direction, for example to the right. For this purpose, the steering devices can each have at least one electromechanical and / or hydraulic actuator. All steerable wheels of the motor vehicle are then deflected at the first steering angle and in the first steering direction. In the next step, the control device controls the drive of the motor vehicle in the first drive direction such that the motor vehicle moves forwards or backwards along the first route, obliquely to the longitudinal direction of the motor vehicle according to the first steering angle. In this case, a first partial lateral offset of the motor vehicle occurs due to the deflected wheels.Since the front and rear wheels are deflected in the same direction and to the same extent, the vehicle ideally moves in a straight line and not in a circular path if the steering angle is not further changed.

[0019] In the second partial sequence, the control device controls both steering devices in such a way that they deflect the front and rear wheels in the same direction by the second steering angle in the second steering direction, for example to the left, if the first partial sequence was to the right. The second steering direction is opposite to the first steering direction. The first and second steering angles can be the same size. The control device then controls the drive in the second drive direction opposite to the first drive direction, so that the motor vehicle moves along the second route. If the motor vehicle was moved forward in the first partial sequence, it is now moved backward in the second partial sequence. This creates a second partial lateral offset of the motor vehicle.Due to the opposing deflection of the wheels and the opposite drive direction of the vehicle, this offset extends in the same direction as the first partial lateral offset. The longitudinal offset that occurred in the first partial sequence is at least partially compensated by the opposite longitudinal offset of the second partial sequence, but can also be overcompensated. After performing the first and second partial sequences once, the vehicle has thus been moved by a total lateral offset, which results from the sum of the first and second partial lateral offsets of the partial sequences.

[0020] If the motor vehicle is moved in the manner described by the method, it performs a type of zigzag movement, which can also be referred to as a "crab walk". In the maneuvering maneuver according to the invention, the total lateral offset of the lateral offset section, i.e. the extent of the sideways movement of the motor vehicle, depends, among other things, on the number of partial sequences of the method carried out. Even with a small movement or a small amount of freedom of movement of the motor vehicle to the front and rear, as well as with small steering angles of the wheels, any desired large lateral offset can be achieved. This is therefore not limited by a maximum steering angle of the wheels, i.e. the angle by which the wheels can be deflected from their zero position when the motor vehicle is traveling straight ahead. However, with a smaller steering angle, more partial sequences must be carried out to achieve the same lateral offset.The ability to repeat the sequence is particularly advantageous because the maximum steering angle by which the rear wheels can be steered is typically significantly smaller than that of the front wheels. Furthermore, the total lateral offset is not limited by the size of the first and second driving sections, so that even with a small maneuvering area in front of and / or behind the vehicle, any desired total lateral offset can be achieved. Similar to the steering angle, the number of sub-sequences to be performed increases as the length of the driving sections decreases.

[0021] Compared to the prior art, the method according to the invention thus enables the motor vehicle to move, particularly automatically, within a significantly more restricted maneuvering area. This increases safety and efficiency when maneuvering in tight spaces or complex environments. For example, it is conceivable for the motor vehicle to move laterally into or out of a parking space automatically and with very little forward and backward offset, for example, only approximately 10 cm in both directions.

[0022] Overall, the use of a transverse offset section of the type described for shunting maneuvers offers a number of advantages.

[0023] The method enables precise and accurate maneuvering maneuvers, taking into account the environment and the constraints. By combining environmental sensors, object detection, and, for example, steer-by-wire technology, the vehicle can be precisely controlled to avoid collisions while reaching a target position, such as an optimal parking position. The approach supports collision avoidance and minimizes the risk of accidents during maneuvering. By taking environmental data into account and, in particular, the automatic detection of objects, potential hazards can be identified and avoided, particularly by providing at least one lateral offset section. The fully automated control of the vehicle and the possibility of more flexible design of the driving trajectory make the maneuvering process more efficient.The method can calculate the best possible driving trajectory and move the vehicle in a confined space by lateral displacement to save time and effort.

[0024] A vehicle system using this method also supports horizontal or atypical maneuvers. It enables maneuvering in various situations and under different constraints, providing greater flexibility in the movement and, in particular, parking of the vehicle.

[0025] In a preferred embodiment of a method according to the invention, the lateral offset section describes a desired overall lateral offset of the motor vehicle, wherein the travel distances and the steering angles as well as the number of partial sequences to be carried out are determined such that the partial lateral offsets of the partial sequences correspond to the overall lateral offset. The extent of the lateral offset section, i.e. the magnitude of the lateral movement of the motor vehicle, can therefore correspond to the desired and predeterminable overall lateral offset. In this way, the magnitude of the lateral movement can be predetermined using the overall lateral offset. As mentioned above, the overall lateral offset corresponds to the sum of the partial lateral offsets of all partial sequences carried out. Depending on a predetermined overall lateral offset, the control device can thus calculate the number of partial sequences necessary to achieve the predetermined overall lateral offset.The steering angle and travel distances can be taken into account or selected appropriately for the situation, the available clearance, and the vehicle's equipment. In other words, the steering angles, travel distances, and the number of sub-sequences can parameterize the lateral offset section, particularly the entire lateral offset, and can be appropriately determined and / or specified when developing the driving trajectory.

[0026] Additionally or alternatively, the travel distance and the steering angle of at least the last partial sequence to be carried out can be determined such that there is no overall longitudinal offset of the motor vehicle over the transverse offset section. The overall longitudinal offset means the offset of the motor vehicle perpendicular to the transverse offset. This can extend along the vehicle's longitudinal axis. It refers to a starting position of the motor vehicle before the transverse offset section is implemented. In other words, the motor vehicle can be moved over the transverse offset section such that at the end of the transverse offset section it is only offset laterally, i.e. in the transverse direction, and not forwards or backwards, i.e. in the longitudinal direction, relative to the starting position. In order to avoid an overall longitudinal offset, the control device can determine the travel distance and the steering angle of the last partial sequence to be carried out accordingly.Alternatively, it can also determine the driving distances and / or steering angles of several sub-sequences accordingly. However, targeted, desired deviations from this are conceivable, such as a targeted determination of the lateral offset section such that a desired overall longitudinal offset remains. For example, when parking in a parking space, the vehicle can then be positioned so that it is at least essentially in the center of the parking space.

[0027] Preferably, a maneuvering interval in the vehicle's longitudinal direction is determined or predefined for the transverse offset section, wherein the steering angles and the travel distances are predetermined such that the motor vehicle remains within the maneuvering interval during the transverse offset section. The maneuvering interval preferably describes the maximum range by which the motor vehicle can or may be moved forwards and backwards in the vehicle's longitudinal direction without colliding with an object in the surroundings along the transverse offset section. It therefore preferably extends over the entire transverse offset section, but in exemplary embodiments can be determined having an extent resolved in the vehicle's transverse direction. By specifying or determining the maneuvering interval, a collision of the motor vehicle when moving along the first and second travel distances can thus be avoided.

[0028] The maneuvering interval is advantageously determined from the environmental data. To this end, the control device can, as mentioned above, examine the environmental data for obstacles and, upon determining the travel trajectory(s), determine a collision-free area around the transverse offset section, from which the maneuvering interval can then be determined. To determine the maneuvering interval, the control device preferably takes into account that part of the environmental data that describes the surroundings of the motor vehicle at least in the maneuvering area of ​​the transverse offset section. This part can be examined for obstacles and possible collisions when executing the determined travel trajectory. The maneuvering interval can have a constant extent in the longitudinal direction of the vehicle along the transverse offset section. However, it can also be determined such that the size of the maneuvering interval changes along the transverse offset section.

[0029] Additionally or alternatively, a maximum permissible extension for the shunting interval can be specified. This can be within a range of 10 cm to 50 cm, particularly 10 cm to 30 cm. For example, it can be 20 cm. This can be stored as a value in the control device or specified by a user.

[0030] When specifying or determining the maneuvering interval, a safety distance can also be taken into account, which describes the minimum distance between the vehicle and surrounding objects. The safety distance can be stored in the control unit or specified by the user. For example, the safety distance can be in a range from 10 cm to 50 cm, preferably 10 cm to 20 cm. The extent of the maneuvering interval can be reduced by the safety distance on one or both sides of the vehicle's longitudinal direction.

[0031] In an advantageous embodiment, the steering angles are selected at least partially, in particular for a maximum possible number of partial sequences, as a maximum possible deflection in the respective steering direction that is possible on both steering devices. The amount of the first and second steering angles is preferably selected to be the same. Both steering angles, i.e. the steering angles in both steering devices, are preferably selected such that they correspond to the maximum possible steering angle on the front wheels and the rear wheels (so-called maximum steering angle). If the maximum steering angle of the front wheels differs from that of the rear wheels, the smaller maximum steering angle is used as the steering angle. In this way, the steering angles are determined such that they correspond to the maximum possible steering angle, while also ensuring that all wheels of the motor vehicle are deflected in the same direction and by the same steering angle.This allows the number of sub-sequences required to achieve the total lateral offset to be kept as low as possible, in particular, minimized. Since the length of the travel distances is usually limited by the environment and / or the safety distance, the steering angle represents the only remaining control variable by which the number of required sub-sequences can be influenced by essentially selecting the maximum possible value.

[0032] The maximum steering angles of the wheels can be predetermined by design or electronically limited by the front and rear axle steering systems. They can be stored on the vehicle side, particularly in the control unit, and can be accessible to the control unit.

[0033] Generally speaking, the steering angle, especially the maximum possible steering angle, can be selected by the control device, for example, within a range of 5° to 15°. For example, the selected (and maximum) steering angle can be 10°.

[0034] According to the invention, a target position for the maneuvering maneuver is determined by the control device from a user input and / or the environmental data. The target position describes the position where the motor vehicle should be after the maneuvering maneuver has been completed. It can be determined automatically by the control device using the environmental data. When determining the target position, a user input can be taken into account in addition to the environmental data. This allows the user to specify the target position of the motor vehicle.

[0035] The user input is made as a voice input and describes the target position with reference to at least one environmental object in the vicinity of the motor vehicle. For example, a microphone can be provided on the motor vehicle side, by means of which a motor vehicle operator can transmit the user input in the form of a voice input to the motor vehicle, specifically to its control device. The user input is made in such a way that it refers to at least one environmental object in the vicinity of the motor vehicle. The control device can therefore localize the target position of the motor vehicle specified in the user input using the environmental data. For example, the user can specify between which other vehicles the vehicle should park and / or next to which peripheral development, or through which narrow spot the vehicle should maneuver.Command input is preferably based on natural language, which simplifies interaction with the vehicle system. The driver can precisely control the vehicle using voice-based commands, preferably by referring to detected objects.

[0036] To support user input based on the environmental data, a representation of the environment, in particular from a bird's eye view, can advantageously be generated and output, wherein the user input, in particular the voice input, relates to environmental objects identifiable within the environmental representation by means of highlighting and / or annotation. The graphical representation of the detected objects and preferably also of the commands generated from voice inputs, for example the driving trajectory, facilitates the comprehensibility and monitoring of the maneuvering process. The representation of the environment can be generated by the control device and output on a display, in particular a touch-sensitive display, in the interior of the motor vehicle or on a mobile device. For example, the environment can be displayed from a bird's eye view in order to provide a user with the best possible overview.It is conceivable that the environment representation can be moved, rotated, and / or scaled by the user in order to obtain the best possible overview before user input. The environment representation can already suggest movement paths of possible travel trajectories, which have already been calculated by the control device based on assumed target positions. Areas of the environment that are inaccessible or passable can be marked as such in the environment representation to alert the user. If the environment representation is displayed on a touch display, user input can be made by touching the desired target position on the touch display.

[0037] The control device can also be configured to detect environmental objects in the environmental data, particularly based on their size and shape, and to highlight them in the environmental representation and / or annotate them. For example, a detected motor vehicle can be labeled "red car" or a detected garage door "garage door." If the user input is in the form of a voice input, the target position of the motor vehicle can be specified based on such annotations. An example voice input could be as follows: "Please park my car as close as possible to the red car in front of the garage door."

[0038] In one embodiment, the user input can be made at least partially via an application of the motor vehicle or a mobile device. Such an application can be, for example, a parking assistance app or a general app of the motor vehicle. This can be provided in a multimedia system of the motor vehicle and / or on a user's mobile device. It is therefore possible for the user input to be made in or on the motor vehicle, in particular in a vehicle interior or from outside the motor vehicle. Additionally or alternatively, the user input can be made, in particular remotely, using the mobile device, for example a cell phone.

[0039] After successful user input, the control unit can determine one or more travel trajectories, taking into account the environmental data as well as the current position and the target position of the vehicle. If several different travel trajectories are possible, these can be shown to the user via the environment display, after which the user can select one of the travel trajectories.

[0040] The shunting maneuver, i.e., the beginning of the execution of the travel trajectory, can begin immediately after a successful user input. The execution of the shunting maneuver is then initiated by the user input.

[0041] Alternatively, an occupant condition can be checked before the start of the maneuvering maneuver. This occupant condition is met or can be met if occupant information indicates that there is currently no person in the motor vehicle, whereby the maneuvering maneuver is only carried out if the occupant condition is met. The occupant information can, for example, be determined sensorily using at least one occupant sensor. This can, for example, be a seat occupancy sensor in a vehicle seat, the sensor data of which indicates whether the vehicle seat is currently occupied, and / or a camera enclosing the interior of the motor vehicle. The occupant condition can therefore be used to check whether there is currently an occupant in the motor vehicle. If this is the case, the maneuvering maneuver is not carried out. In this embodiment, the maneuvering maneuver is therefore only carried out if there is currently no person in the motor vehicle.This can increase safety for one or more people.

[0042] Furthermore, the vehicle can be particularly advantageously maneuvered into target positions where exiting would no longer be possible, for example, tight parking spaces and / or near peripheral structures such as walls. This further demonstrates that the vehicle is capable of performing the maneuver independently, with no person required to monitor the maneuver.

[0043] Alternatively or additionally, a locking condition can be checked before the start of the maneuvering maneuver. This locking condition is fulfilled or can be fulfilled if locking information indicates that the motor vehicle is currently locked, whereby the at least one maneuvering maneuver is only carried out if the locking condition is fulfilled. The locking information can be specified using a locking sensor and / or a locking control unit of the motor vehicle. By checking the locking condition, it can be ensured that the maneuvering maneuver is only carried out if the motor vehicle is currently locked. This ensures that no doors are opened unexpectedly during the autonomous execution of the maneuvering maneuver and that locking is not forgotten after parking, for example when parking due to the maneuvering maneuver.

[0044] In an exemplary embodiment, a user can specify a parking position of the motor vehicle as the target position via voice input. The user can then exit and lock the motor vehicle. Immediately after locking, the user can move away from the motor vehicle and continue with their activities. After successfully checking the occupant condition and the locking condition, the motor vehicle will perform the maneuvering maneuver independently, without user supervision.

[0045] Preferably, the control device is configured to use the environmental data to determine hazard information relating to the presence of a hazard. During the maneuvering maneuver, the control device can continuously check for a hazard condition that is met or can be met if the hazard information indicates that a hazard object is currently located in the vicinity of the motor vehicle. Such a hazard object can be, for example, a person, in particular a child, or an animal, or the like. If the hazard condition is met, the maneuvering maneuver, in particular the movement of the motor vehicle, can be stopped immediately. The hazard condition can also be met or can be met if vehicle information relating to a current state of the motor vehicle indicates that the execution of maneuvers is at risk due to the current state of the motor vehicle.This can be the case, for example, if brake pads are too worn.

[0046] The surroundings and / or the condition of the motor vehicle can thus be continuously monitored by the control device throughout the entire maneuver, which leads to increased safety. In particular, the control device can implement a collision protection system that can react appropriately to impending collisions, particularly with dynamic surrounding objects, and can adapt the maneuver and / or at least temporarily stop it.

[0047] In addition to the method according to the invention, the invention also relates to a motor vehicle comprising - a front axle with steerable front wheels and a front axle steering device for steering the front wheels, - a rear axle with steerable rear wheels and a rear axle steering device for steering the rear wheels, - at least one drive for driving the front wheels and / or the rear wheels, and - a control device designed to control the front axle steering device, the rear axle steering device and the drive.

[0048] The motor vehicle according to the invention is characterized in that the control device is designed to carry out a method according to the invention.

[0049] All features and advantages of the method according to the invention can therefore be transferred to the motor vehicle according to the invention and vice versa.

[0050] The motor vehicle according to the invention has two or more steerable wheels on the front axle and the rear axle. The front-axle steering device and the rear-axle steering device can have at least one, in particular electromechanical or hydraulic, actuator for steering the respective wheels, which actuator can be controlled by the control device. The at least one drive can comprise an internal combustion engine and / or an electric motor of the motor vehicle, wherein the front axle and the rear axle can be driven by the same drive or a drive assigned to the respective axle. It is also conceivable that only one of the two axles is drivable. The motor vehicle is preferably configured for autonomous driving. The control device can be part of a vehicle system designed for the fully automatic guidance of the motor vehicle.

[0051] The control device can be provided in the motor vehicle or at least with one part inside the motor vehicle and another part externally, outside the motor vehicle. For example, part of the control device can be an external server (backend) that evaluates the environmental data and / or with which the driving trajectory is calculated. The server can communicate with the vehicle-side part of the control device for data transmission, for example, via a corresponding communication device.

[0052] In a preferred embodiment, the motor vehicle has at least one environmental sensor for detecting environmental data. The at least one environmental sensor can comprise a camera, a radar sensor, a lidar sensor, and / or other sensors suitable for environmental detection.

[0053] Additionally or alternatively, the motor vehicle can have at least one occupant sensor for determining the occupant information. For example, a seat occupancy sensor in the form of a pressure sensor can be provided in each vehicle seat, with the at least one pressure sensor being configured to detect a person sitting on the respective vehicle seat. Other occupant sensors are also conceivable, for example, in the form of a camera in the vehicle interior.

[0054] Additionally or alternatively, the motor vehicle can have at least one locking control unit for determining the locking information, with which a current locking state can be provided in the form of the locking information.

[0055] Each of the sensors described above and each of the control devices described above is preferably connected to the control device for data transmission and / or forms part of the control device.

[0056] The motor vehicle preferably has at least one graphic display device by means of which the surroundings and / or the driving trajectory calculated as a function of the user input can be presented to a user of the motor vehicle. The display device can comprise a display, in particular a touch-sensitive display (touch display). It is also conceivable for the display device to comprise a head-up display. The display device can be provided in an interior of the motor vehicle, in particular in a dashboard. Alternatively, the display device can be a display of a mobile device, for example a mobile phone. The current surroundings of the motor vehicle and / or the one or more calculated driving trajectories can be presented to the user by means of the display device.The latter can then, based on the information displayed in the form of at least one user input, specify and / or adjust a target position in which the motor vehicle should be at the end of the manoeuvre.

[0057] The motor vehicle and / or the mobile device preferably has at least one input device, in particular a microphone, for detecting the at least one user input. The at least one user input can be made, for example, by touching the display device. The display device can therefore simultaneously be the input device. Additionally or alternatively, the input device can comprise at least one operating element, for example, a button or a rotary control.

[0058] Particularly advantageously, the at least one input device can be a microphone. The at least one user input can then be made in the form of a voice input. The at least one microphone can be provided in or on the motor vehicle such that the at least one user input can be made inside the motor vehicle or in the immediate vicinity of the motor vehicle, for example, within a radius of up to 10 m around the motor vehicle, outside the motor vehicle. A speech recognition unit can then convert the user input into text, for example.

[0059] Further advantages and details of the invention will become apparent from the following exemplary embodiments and the accompanying drawings. These schematically show: Fig. 1 a schematic diagram of an embodiment of a motor vehicle according to the invention, Fig. 2 a flow chart of an embodiment of a method according to the invention, Fig. 3 a flow chart of part of the procedure of Fig. 3 for moving a transverse offset section of the motor vehicle of the Fig. 1, and Fig. 4 a schematic diagram of a part of a driving trajectory that corresponds to the schedule of the Fig. 2 was determined.

[0060] Fig. 1 shows an embodiment of a motor vehicle 1 according to the invention. This has a front axle 2 with steerable front wheels 3 and a rear axle 4 with steerable rear wheels 5. In addition to the generally conventional front-axle steering, the motor vehicle 1 also has rear-axle steering. The front axle 2 comprises a front-axle steering device 6, which is designed to steer the front wheels 3. Analogously, the rear axle 4 also has a rear-axle steering device 7, which is designed to steer the rear wheels 5. The steering devices 6, 7 each have an electromechanical actuator, by means of which the wheels 3, 5 of the respective axle 2, 4 are conceivable. The controllable electromechanical actuator enables, for example, a so-called "steer-by-wire" steering system.

[0061] The steering devices 6, 7 can be controlled by a control device 8 of the motor vehicle 1 to steer the wheels 3, 5. Furthermore, the front wheels 3 and the rear wheels 5 can be driven by a drive 9 of the motor vehicle 1. In the present case, this is an electric motor. However, it can also be an internal combustion engine, whereby the motor vehicle 1 can also have multiple drives 9. The drive 9 can also be controlled by the control device 8.

[0062] For the purpose of orientation, the Fig. 1 shows a vehicle coordinate system which specifies a vehicle longitudinal direction 100, a vehicle transverse direction 200 and a vehicle vertical direction 300.

[0063] In the Fig. In the state shown in Figure 1, the front wheels 3 and the rear wheels 5 of the motor vehicle 1 are deflected in the same direction by a steering angle L. The reference angle is the orientation of the wheels 3, 5 when the motor vehicle is traveling straight ahead. The wheels 3, 5 are deflected to the right 100° when viewed in the vehicle's longitudinal direction.

[0064] The control device 8 is designed to carry out the process of Fig. 2 and Fig. 3. In the course of this, the motor vehicle 1 is moved completely automatically by steering and driving the wheels 3, 5. The movement describes a maneuver of the motor vehicle 1 and is shown in detail as an example in Fig. 4. This shows a driving trajectory 10 which is used when carrying out the method of Fig. 2 and Fig. 3 is determined and executed by the control device 8. The procedure is explained below:

[0065] Fig. Figure 2 shows a flow chart of the entire method, at the end of which a maneuvering maneuver is carried out to achieve a transverse offset section of the motor vehicle 1. The part of the method for implementing the transverse offset section is described in detail in Fig. 3 in the form of another flow chart.

[0066] In Fig. 2, in a step S1, environmental data 11 are first acquired, which describe the surroundings of the motor vehicle 1. They describe at least one potential maneuvering area for the maneuvering maneuver. To acquire the environmental data 11, the motor vehicle has several environmental sensors 12, in this case a camera 13, a lidar sensor 14, and a radar sensor 15 (see Fig. 1). The environmental sensors 12 are connected to the control device 8 for transmitting the environmental data 11.

[0067] In step S2, the environmental data 11 are processed by the control device 8, in particular for object recognition, and graphically presented to a user in the form of an environmental representation 18 on a display device 16, in this case, for example, a touch display 17. In addition to the touch display 17 of the motor vehicle 1, a mobile device, specifically a mobile phone, is provided, which has a display that also represents a display device 16.

[0068] The environmental representation 18 is shown from a bird's-eye view. During processing, the control device 8 detects environmental objects, such as motor vehicles and / or garage doors and / or obstacles such as garbage containers, in the environmental data 11 and marks them as such in the environmental representation 18. The detected environmental objects are thus highlighted. In addition, they are provided with annotations in the environmental representation 18, such as "red car" or "garage door." With the environmental representation 18, the user of the motor vehicle 1 can obtain a good overview of the surroundings. If the surroundings are displayed on the display device 16 of a mobile device, the user does not have to be in or near the motor vehicle 1.

[0069] Subsequently, in a step S3, a user input 19 is made, through which the user specifies a target position Z in which the motor vehicle 1 should be at the end of the maneuvering maneuver. To capture the user input 19, the motor vehicle 1 has three input devices 20, namely the aforementioned touch display 17, which simultaneously serves as a display device 16, a microphone 21 in the interior of the motor vehicle 1, and another microphone 21 configured to receive an audio signal from outside the motor vehicle 1.

[0070] The user input 19 can thus be made by touching the touch display 17, with which the user specifies the target position Z of the motor vehicle in the environmental representation 18. Alternatively, the user can specify the target position Z by voice input as user input 19, which is recorded by the control device 8 through the microphone(s) 21 or one of the microphones 21. For this purpose, the user can use the annotations or titles of the environmental objects inserted in the environmental representation 18.

[0071] An example voice input could be as follows: “Please park my vehicle between the blue container and the green car, as close to the curb as possible.”

[0072] In the subsequent step S4, the control device 8 determines the travel trajectory 10 based on the environmental data 11 and the user input 19, including the target position Z. This describes the movement that the motor vehicle 1 must or can travel in order to reach the target position Z from the current position of the motor vehicle with the least possible maneuvering effort. The control device 8 can also determine several possible travel trajectories 10 and display the one or more travel trajectories 10 in the environmental representation 18 on the display device 16, visible to the user again. If several possible travel trajectories 10 are available, the user can select one of the travel trajectories 10 by entering a new user input 19.

[0073] If a travel trajectory 10 to be executed has been determined at the end of step S4, the user, if currently in the vehicle, leaves the motor vehicle 1. Subsequently, the control device 8 checks an occupant condition B1, the fulfillment of which depends on occupant information 22. The occupant information 22 indicates whether there is currently an occupant in the motor vehicle 1. To determine the occupant information 22, the motor vehicle has an occupant sensor 23 in each vehicle seat. This is a pressure sensor that can be used to detect whether a vehicle seat is occupied. If the occupant information 22 indicates that there is currently an occupant in the motor vehicle 1, the occupant condition B1 is not fulfilled. In this case, the method is interrupted, for example with the output of a notification, and can only be continued when the occupant condition B1 is fulfilled. Alternatively, the method can be aborted.If, however, the occupant information 22 indicates that there is currently no occupant in the motor vehicle 1, the occupant condition B1 is met. The process then continues.

[0074] If the occupant condition B1 is met, a locking condition B2 is evaluated by the control device 8. This locking condition B2 depends on a piece of locking information 24 that describes a current locking state of the motor vehicle 1. The locking information 24 is forwarded to the control device 8 by a locking control unit 25. If the locking information 24 indicates that the motor vehicle 1 is currently not locked, the locking condition B2 is not met. The method is then interrupted, in particular with the output of a notification, and can only be continued once the locking condition is met. Alternatively, it can be aborted entirely. If, however, the locking information 24 indicates that the motor vehicle 1 is currently locked, the maneuvering maneuver is performed in the subsequent step S5.

[0075] If the occupant condition B1 or the locking condition B2 is not met, the control device 8 can issue a message to the user on the display device 16 that all occupants must leave the motor vehicle 1 or that the motor vehicle 1 must be locked in order to initiate the maneuver. If the respective condition is still not met after a waiting period of, for example, 30 seconds, the process is aborted.

[0076] The following is based on Fig. 3 and Fig. 4 describes the part of the method by which a transverse offset section of the travel trajectory 10 is implemented when maneuvering the motor vehicle (see Fig. 4): At the start of the maneuvering maneuver, the motor vehicle 1 moves along the travel trajectory 10 into a starting position A to the side of a parking space 26 which, in the illustrated vehicle longitudinal direction 100, is only slightly larger than the length of the motor vehicle 1. From the starting position A, the control device 8 automatically maneuvers the motor vehicle 1 in a zigzag movement along the transverse offset section into the parking space 26, where it is then positioned in the predetermined target position Z. This movement can also be referred to as a crab walk. It allows any desired total transverse offset Q to be achieved even in a very tight maneuvering area. For clarity, the portion of the travel trajectory 10 forming the transverse offset section is not shown to scale, in particular larger than the indicated outer edges of the motor vehicle 1 in the starting position A and the target position Z.

[0077] The implementation of the transverse offset section (see Fig. 3) is again carried out by the control device 8 of the motor vehicle 1 and comprises a first and a second partial sequence T. In the first partial sequence T, in a step S6, both steering devices 6, 7 are controlled by the control device 8 in such a way that the front wheels 3 and the rear wheels 5 are turned in the same direction by a first steering angle L in a first steering direction, in this case exemplarily to the right (see Fig. 1). In a subsequent step S7 of the first subsequence T, the drive 9 of the motor vehicle 1 is controlled by the control device 8 in a first drive direction, in this case by way of example forward in the vehicle longitudinal direction 100. The motor vehicle 1 is thereby moved along a first travel distance F. As the wheels 3, 5 are steered in the same direction at the first steering angle L during the movement, the motor vehicle moves straight forward and to the right, so that a first partial transverse offset 26 is present. In order to achieve the total transverse offset Q in a reasonable manner, the first steering angle L is selected as the maximum possible steering angle in this first steering direction (here by way of example to the right) on both steering devices 6, 7.

[0078] Step S7 is followed by a check of a termination condition B3, which is fulfilled when the motor vehicle 1 is currently located at the target position Z, thus the transverse offset section, which ends here at the target position Z, has ended. If the termination condition B3 is fulfilled, the maneuvering maneuver is terminated in step S8. If it is not fulfilled, the second sub-sequence T is carried out. If the Fig. 3 is carried out for the first time, the termination condition B3 cannot be met during the initial check, so that both subsequences T are always carried out at least once.

[0079] In the second subsequence T, the control device 8 controls the two steering devices 6, 7 in a step S9 such that all wheels 3, 5 of the motor vehicle 1 are deflected in the same direction by a second steering angle L in a second steering direction opposite to the first steering direction. The amount of the steering angle L is the same (thus again the maximum possible steering angle on both the front axle 2 and the rear axle 4), only the wheels 3, 5 are now deflected to the left. Subsequently, in step S10, the control device 8 controls the drive 9 in a second drive direction opposite to the first drive direction, so that the motor vehicle 1 is moved along a second travel path F. Here, too, the deflection of the wheels 3, 5 in the same direction results in a partial lateral offset 26 of the motor vehicle 1.

[0080] Subsequently, the termination condition B3 is checked again. If the motor vehicle 1 is still not in the target position Z, the first subsequence T is executed again, with the termination condition B3 being checked again. The subsequences T are executed alternately one after the other until the motor vehicle 1 is in the target position Z and the termination condition B3 is met, and the maneuvering maneuver is terminated in step S8. This means that when determining the travel trajectory 10, the control device 8 has already determined or selected the corresponding parameters such that the lateral guidance section ends at the target position Z.

[0081] In step S4 (see Fig. 2) a total transverse offset Q is determined by which the motor vehicle 1 is displaced in the transverse direction (vehicle transverse direction 200 in Fig. 4) must be moved in order to reach the target position Z. The transverse offset section realizes this total transverse offset Q. The travel distances F and the steering angles L are determined by the control device 8 in such a way that the sum of the partial transverse offsets 26 of the partial sequences corresponds to the total transverse offset Q. At the end of a partial sequence T, the motor vehicle 1 is then in the target position Z. In addition, the travel distance F and the steering angle L of at least the last completed partial sequence T are determined by the control device 8 in such a way that there is no total longitudinal offset of the motor vehicle 1 over the transverse offset section Q. This is determined using Fig. 4. In the vehicle's longitudinal direction 100, the motor vehicle 1 is not offset in the target position Z relative to the starting position A. Thus, there is no overall longitudinal offset. For example, the motor vehicle 1 can be positioned centrally in the parking space 26.

[0082] Since only a limited space is available for the motor vehicle 1 to complete the transverse offset section, thus the travel distances F are limited, the control device 8 further determines a permissible maneuvering interval R for the transverse offset section in step S4. This specifies a permissible freedom of movement of the motor vehicle 1 along the transverse offset section in the vehicle longitudinal direction 100. Based on this, the steering angle L and the travel distances F are determined such that the motor vehicle 1 remains within the maneuvering interval R during the transverse offset section Q. The maneuvering interval R is determined by the control device 8 depending on the environmental data 11. In the present case, the maneuvering interval R has, for example, a maximum permissible extent of 20 cm, in Fig. 4 i.e. from the starting position A of the motor vehicle in the vehicle's longitudinal direction 100 by 10 cm each to the front and rear.

[0083] When determining the maneuvering interval R, the control device 8 takes into account a safety distance 27, which describes a minimum distance of the motor vehicle 1 to surrounding objects 28 and in the present case is, for example, 20 cm.

[0084] In order to move the motor vehicle 1 as quickly as possible to the target position Z with as few subsequences T as possible, the steering angle L is determined by the control device 8 such that it corresponds to the smaller of the two maximum steering angles on the front axle 2 and the rear axle 4, as already explained. The maximum steering angle is the angle by which the wheels 3, 5 of the respective axle can be maximally deflected. The maximum steering angles of both axles 2, 4 are stored in the control device 8. Of these, the smaller maximum steering angle, typically the rear axle 4, is used as the steering angle L. In this way, maximum deflection of all wheels 3, 5 by the same steering angle L can be achieved. In the present case, the steering angle L remains the same over the entire transverse offset section Q, for example, with only the steering direction being changed back and forth with each subsequence T.In order to manage with as few partial sequences as possible, the route F is chosen as far as possible and reasonable as maximum, so that the motor vehicle 1 remains in the shunting interval R.

[0085] Overall, the motor vehicle 1 can therefore automatically maneuver in a much more restricted maneuvering area (see Fig. 4) maneuver. The motor vehicle 1 can move sideways any distance in the vehicle's transverse direction 200, i.e., by any transverse offset section Q, during a slight forward and backward movement, in this case, for example, 10 cm, by steering the front wheels 3 and rear wheels 5 in the same direction.

Claims

[1] Method for operating a fully automatically movable motor vehicle (1), comprising a front axle (2) with front wheels (3) steerable by a front axle steering device (6), a rear axle (4) with rear wheels (5) steerable by a rear axle steering device (7), a drive (9) for driving the front wheels (3) and / or the rear wheels (5), and a control device (8), wherein the control device (8) is designed to determine and execute a travel trajectory (10) for a manoeuvring maneuver, in particular a parking maneuver, using environmental data (11) describing at least one potential manoeuvring area for manoeuvring maneuvers, wherein the travel trajectory (10) has a transverse offset section (Q), for the implementation of which the control device (8) carries out the following partial sequences (T) of steps at least once in alternation: In a first subsequence (T), - controlling the front axle steering device (6) and the rear axle steering device (7) to deflect the front wheels (3) and the rear wheels (5) in the same direction by a first steering angle (L) in a first steering direction, - controlling the drive (8) with a first drive direction for moving the motor vehicle (1) along a first route (F), and in a second subsequence (T), - controlling the front axle steering device (6) and the rear axle steering device (7) to deflect the front wheels (3) and the rear wheels (5) in the same direction by a second steering angle (L) in a second steering direction opposite to the first steering direction, and - controlling the drive (9) with a second drive direction opposite to the first drive direction for moving the motor vehicle (1) along a second route (F), characterized by , that a target position (Z) of the shunting maneuver is determined by means of the control device (8) from a user input (19) and the environmental data (11), wherein the user input (19) is made as a voice input and describes the target position (Z) with reference to at least one environmental object (27) of the environment of the motor vehicle (1). [2] Method according to claim 1, characterized by that the transverse offset section (Q) describes a desired overall transverse offset of the motor vehicle (1), wherein the travel distances (F) and the steering angles (L) as well as the number of partial sequences (T) to be carried out are determined such that the partial transverse offsets (26) of the partial sequences (T) correspond to the overall transverse offset, and / or that the travel distance (F) and the steering angle (L) of at least the last partial sequence (T) to be carried out are determined such that there is no overall longitudinal offset of the motor vehicle (1) over the transverse offset section (Q). [3] Method according to claim 1 or 2, characterized by that a manoeuvring interval (R) in the vehicle's longitudinal direction (100) is determined or specified for the transverse offset section (Q), wherein the steering angles (L) and the travel distances (F) are predetermined such that the motor vehicle (1) remains within the manoeuvring interval (R) during the transverse offset section (Q). [4] Method according to claim 3, characterized by that the shunting interval (R) is determined from the environmental data (11) and / or a maximum permissible extent, in particular in the range of 10 to 50 cm, is specified for the shunting interval (R). [5] Method according to one of the preceding claims, characterized by that the steering angles (L) are selected at least partially, in particular for a maximum possible number of partial sequences (T), as a maximum possible deflection in the respective steering direction that is possible on both steering devices. [6] Method according to one of the preceding claims, characterized byin that, to support the user input (19), an environmental representation (18), in particular from a bird's eye view, is generated and output on the basis of the environmental data (11), wherein the user input (19), in particular the voice input, relates to environmental objects (27) that can be identified within the environmental representation (18) by means of highlighting and / or annotation. [7] Method according to one of the preceding claims, characterized by that the user input (19) is made at least partially via an application of the motor vehicle or a mobile device. [8] Method according to one of the preceding claims, characterized by that before the start of the manoeuvring manoeuvre, an occupant condition (B1) is checked, which is fulfilled or can be fulfilled if occupant information (22) indicates that there is currently no person in the motor vehicle (1), wherein the manoeuvring manoeuvre is only carried out if the occupant condition (B1) is fulfilled. [9] Method according to one of the preceding claims, characterized by that before the start of the manoeuvring manoeuvre, a locking condition (B2) is checked, which is fulfilled or can be fulfilled if a locking information item (24) indicates that the motor vehicle (1) is currently locked, wherein the at least one manoeuvring manoeuvre is only carried out if the locking condition (24) is fulfilled. [10] Motor vehicle (1), comprising - a front axle (2) with steerable front wheels (3) and a front axle steering device (6) for steering the front wheels (3), - a rear axle (4) with steerable rear wheels (5) and a rear axle steering device (7) for steering the rear wheels (5), - at least one drive (9) for driving the front wheels (3) and / or the rear wheels (5), and - a control device (8) which is designed to control the front axle steering device (6), the rear axle steering device (7) and the drive (9), characterized by that the control device (8) is designed to carry out a method according to one of the preceding claims. [11] Motor vehicle (1) according to claim 10, characterized by that the motor vehicle (1) has at least one environmental sensor (12) for detecting the environmental data (11) and / or at least one occupant sensor (23) for determining the occupant information (22) and / or at least one locking control device (25) for determining the locking information (24). [12] Motor vehicle (1) according to claim 10 or 11, characterized bythat the motor vehicle (1) has at least one graphic display device (16) by means of which the surroundings and / or the travel trajectory (10) calculated as a function of the user input (19) can be displayed to a user of the motor vehicle (1). [13] Motor vehicle (1) according to one of claims 10 to 12, characterized by that the motor vehicle (1) has at least one input device (20), in particular a microphone (21), for detecting the at least one user input (19).

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