DE102022202130A1 - Method and device for increasing driving comfort for occupants of an at least partially autonomous vehicle - Google Patents

Abstract

The present invention relates to a method for increasing driving comfort for occupants of an at least partially autonomous vehicle with at least one steerable front axle and a rear axle that can be steered independently thereof, with the steps: determining a section of route to be traveled by the vehicle in the future using a navigation system; Determining an optimized slip angle for future cornering by a processor device; Controlling an actuator for setting a turning angle of the front and/or rear axle for corner entry in accordance with the optimized slip angle precalculated by the processor device; Controlling an actuator for adjusting a turning angle of the front and/or rear axle for corner exit in accordance with the optimized vehicle alignment pre-calculated by the processor device; and changing the sign of the angle of the angle of the rear axle with respect to the longitudinal axis of the vehicle at least once while driving through a curve. The invention further relates to a device for increasing driving comfort for occupants of an at least partially autonomous vehicle and a corresponding vehicle.

Description

The present invention relates to a method and a device for increasing driving comfort for occupants of an at least partially autonomous vehicle while cornering. The invention also relates to a vehicle that is equipped with such a device or is set up to carry out this method.

For some time now, vehicle development has essentially pursued the three goals of making vehicles more energy efficient, safer and/or more comfortable. The engine and the body, for example, have a significant influence on this - especially with regard to energy efficiency. The engine has an influence, for example, through the selection of its power, the energy source used to propel the vehicle and its weight, the body, for example through its shape and weight. However, many of these variables are not freely selectable or have already been optimized in such a way that the effort required is no longer in proportion to the benefit.

Therefore, in the past, there have been increasing attempts to find other ways to monitor and optimize the driving behavior of a vehicle. Particularly in connection with developments in (partially) autonomous driving, vehicles have been developed that contain a large number of sensors that determine vehicle data and/or environmental data. This data is used to determine a suitable driving mode, which, on the one hand, ensures the safety of the vehicle, its occupants and other road users and, on the other hand, also allows the vehicle to drive in the most energy-saving mode possible. For example, in vehicles with internal combustion engines, it is state of the art not to use one or more cylinders if their power is not required.

The sensors and actuators contained in modern vehicles can also be used to increase driving comfort. This can be done, for example, by a (partially) autonomous vehicle control adjusting the vehicle speed at an early stage, for example based on the information available for the pre-calculated route regarding route utilization, traffic light control and speed specifications. This allows abrupt changes in speed to be reduced and the acceleration forces acting on the vehicle occupants to be reduced. Especially in (fully) autonomous driving, all vehicle occupants are passengers who should be able to travel as pleasantly and comfortably as possible. Distractions and interruptions of other activities carried out during the journey, such as reading, writing, working or playing, due to unexpected or sudden vehicle maneuvers with a large rate of change in acceleration should be avoided.

Vehicles with rear-axle steering are also known from the prior art. Such steering of the rear axle usually serves to increase the agility of a vehicle (particularly at low speeds). For example, additional rear-axle steering can assist in parking the vehicle. It is also known that safety can be increased through additional rear-axle steering (particularly at higher speeds). This can be justified in particular by improving the stability of the vehicle when cornering.

An example of such a control is in the DE 10 2015 212 229 B4 disclosed. To keep the vehicle on track, the rear wheels are controlled individually or together. In addition, to prevent the front wheels from resetting, they are also controlled individually or together. This control creates a yaw moment about the vertical axis of the vehicle and thus also a lateral force acting on the front axle or the front wheels. The main advantage stated in this publication is that these interventions ensure lane keeping and are practically not noticed by the driver. The driver can continue to use the steering wheel to specify the direction of travel as usual and the vehicle follows this direction without the driver feeling any moment on the steering wheel, as would be the case with active steering. Such rear-axle steering can counteract the vehicle's swerving in curves to a certain extent.

On the other hand, it is known that in vehicles with additional rear-axle steering, a driving feeling similar to oversteering and / or swerving of the vehicle (which also occurs when drifting and is also sometimes referred to as drifting in the context of this invention) can be specifically brought about or simulated while at the same time stable vehicle control can.

For example, this is off DE 10 2018 220 575 A1 It is known that the driving maneuver of drifting - as previously known from motor vehicles with non-steerable rear wheels - can be specifically simulated with a motor vehicle with additionally steerable rear wheels. By additionally using the rear wheel steering, a driving maneuver comparable to drifting is carried out in terms of vehicle movement. A real drifting, i.e. sliding or pushing over The rear wheels are not intentional; the driver simply has the impression that the vehicle is drifting.

A method in which drifting is specifically caused in vehicles where it would normally not be permitted due to a negative force/mass ratio is out DE 10 2017 001 449 A1 known. Cornering is initiated by a first drift mode, in which a slip angle of a rear axle of the vehicle is adjusted so that wheels of the rear axle are aligned in the direction of the outside of the curve. Subsequently, in a second drift mode, the slip angle of the rear axle of the vehicle is adjusted so that the wheels of the rear axle are aligned in the direction of the inside of the curve depending on a specified driving dynamic limit value and the vehicle oversteers. Unlike the subject of the previously mentioned DE 10 2018 220 575 A1 This specifically triggers oversteering of the vehicle and thus actual drifting.

As explained above, it is generally known that a vehicle with rear-wheel steering can be brought into certain driving modes, but the known methods and devices each serve either to stabilize the vehicle while cornering by preventing oversteer or to specifically prevent oversteer or drifting to trigger. Methods and devices that increase the driving comfort of vehicle passengers are not known. The task is therefore to provide a device and a method which increases driving comfort when cornering.

The object is achieved according to the invention by the subjects of the independent claims. Advantageous embodiments and further developments of the invention are the subject of the subclaims.

• - Ermitteln eines von dem Fahrzeug zukünftig zu befahrenden Streckenabschnitts durch ein Navigationssystem,
• - Ermitteln eines optimierten Schwimmwinkels für eine zukünftige Kurvenfahrt durch eine Prozessoreinrichtung,
• - Ansteuern eines Aktuators zur Einstellung eines Einschlags der vorderen und/oder der hinteren Achse für eine Kurveneinfahrt entsprechend des von der Prozessoreinrichtung vorberechneten optimierten Schwimmwinkels,
• - Ansteuern eines Aktuators zur Einstellung eines Einschlags der vorderen und/oder der hinteren Achse für eine Kurvenausfahrt entsprechend der von der Prozessoreinrichtung vorberechneten optimierten Fahrzeugausrichtung, und
• - Mindestens einmaliges Ändern des Vorzeichens des Winkels des Einschlags der hinteren Achse bezüglich der Fahrzeuglängsachse während einer Kurvendurchfahrt.

A solution to this problem consists in a method for increasing driving comfort for occupants of an at least partially autonomous vehicle with at least one steerable front axle and a rear axle that can be steered independently of it. This procedure includes the steps:

• - Determining a section of route to be traveled by the vehicle in the future using a navigation system,
• - Determining an optimized slip angle for future cornering by a processor device,
• - Controlling an actuator for setting a turning angle of the front and/or rear axle for corner entry in accordance with the optimized slip angle pre-calculated by the processor device,
• - Controlling an actuator for setting a turning angle of the front and/or rear axle for corner exit in accordance with the optimized vehicle alignment pre-calculated by the processor device, and
• - Changing the sign of the angle of the rear axle with respect to the vehicle's longitudinal axis at least once while driving through a curve.

Driving through a curve should be understood as driving along a section of route which, at least in sections, has an arbitrary route with a non-constant curve curvature. The curves of the curves can also be zero in sections, i.e. the route section can have one or more straight sections.

Surprisingly, it was found that by changing the sign of the angle of the angle of the rear axle with respect to the vehicle's longitudinal axis at least once during a curve, a particularly comfortable curve can be achieved for the occupants, since extreme acceleration changes in a short time (high back) are avoided can. In contrast to the drifting described at the beginning as prior art and the conscious creation of this driving state in order to cause the suddenly occurring acceleration peaks (strong slope in an acceleration/time diagram), it is possible with the method according to the invention to detect such acceleration peaks and to avoid particularly large gradients in an acceleration/time diagram. This is particularly true in connection with the 5 and 6 Acceleration/time diagrams shown.

A large rate of change in acceleration is also referred to as sudden acceleration in the context of this invention. A rate of change in the acceleration of a body over time is called a “jerk” in kinematics. The jerk corresponds to the first derivative of the acceleration with respect to time. A short-term acceleration is usually characterized by a large gradient in an acceleration-time diagram. Accordingly, the magnitude of the derivative of the acceleration over time is large at this point. Such short-term or abrupt accelerations or jerks are caused by vehicle occupants often perceived as particularly disturbing and unpleasant.

In the context of this invention, in many cases a distinction is made between kinematic acceleration and the acceleration acting on occupants. Unless otherwise stated, acceleration is understood to mean the acceleration acting on occupants. The kinematic acceleration is usually indicated by a curve in the direction of movement and speed. Its direction and size are determined, for example, by factors such as the curve radius and (change in) speed of the vehicle. This acceleration vector can be broken down into two vectors, a first tangential and a second normal to the trajectory. The first of these two vectors defines the tangential acceleration. It describes the change in speed over time and forms a tangent to the trajectory. The second of these two vectors defines the normal acceleration. It describes the change in speed direction over time. If you know it, you can use it to determine a measure of the curvature of the trajectory.

In contrast, the present invention preferably aims to change the acceleration acting on occupants and therefore also the jerk acting on them so that this is perceived as less disturbing for vehicle occupants and a more comfortable driving experience is created. For this purpose, a vehicle-fixed reference system is preferably used, in which a distinction is made between the acceleration (or jerk) acting on occupants between the acceleration (or jerk) in the longitudinal and transverse directions (with respect to the vehicle's longitudinal axis).

The amount of acceleration acting on the occupants (and felt by the occupants) is equal to the kinematic acceleration (since it is based on a different reference system). However, within the framework of the proposed solution, it is preferably possible to change the direction of the acceleration acting on the passengers (longitudinal and lateral acceleration) by means of a suitable vehicle alignment. For example, this can convert a kinematic longitudinal acceleration (or tangential acceleration) of the vehicle into a lateral acceleration felt (by an occupant) and vice versa.

Preferably, the decoupling of the longitudinal and lateral acceleration from the tangential acceleration and normal acceleration creates opportunities to change the direction of the acceleration acting on a vehicle occupant and thus reduce the amount of jerk felt. This is perceived as an increase in comfort. Since the tolerance for accelerations felt by a vehicle occupant in the transverse and longitudinal directions can also be different, a controlled redistribution of the total acceleration acting on the occupant into portions in the longitudinal and transverse acceleration that can be achieved by the present invention can further increase comfort become.

In particular, in order to avoid large backs, it has proven to be advantageous if the actuator is activated to adjust an angle of the front and/or rear axle for entering a curve before the vehicle enters the curve and/or the sign of the angle of the The impact of the rear axle with respect to the vehicle's longitudinal axis is maintained at least temporarily after the vehicle exits the curve. Preferably, with the help of the actuators on the front and rear axles, a slip angle is built up before entering a curve and a changed slip angle is kept short and/or slowly reduced after exiting a curve.

One of these measures or their combination can be used to change the direction of the accelerations acting on a vehicle occupant. This makes it possible to buffer kinematic acceleration peaks acting in one direction, as shown below, by distributing them in different perception directions. Preferably, it is possible to keep the changes in direction of the overall acceleration affecting vehicle occupants small. In addition, it may also be possible to make an acceleration peak less disruptive by distributing it spatially and/or temporally (i.e. over a larger distance and/or over a longer period of time). Any one of these measures or any combination of them means that the perceived accelerations in each direction can be built up and reduced more slowly, which leads to lower backs. This preferably also results in a direction of the sum of the accelerations acting on a vehicle occupant changing more slowly. This is preferably also accompanied by the fact that the different acceleration tolerances in the longitudinal and transverse directions can be better adhered to. Strong gradients in the acceleration/time diagram can therefore be avoided particularly efficiently - by redistributing the acting forces and/or because a longer distance and thus a longer period of time is available. This has an advantageous effect on the vehicle occupants as they are not affected by sudden acceleration peaks other activities such as sleeping, meetings, reading, work or playing.

In a preferred method variant, when determining a route section to be traveled by the vehicle in the future, a width of the available route section is taken into account. Preferably, the result of such a determination of the route section to be traveled by the vehicle in the future is therefore not a line but a strip. This makes it possible not only to define the position of the vehicle on a line, but also to determine a permitted orientation of the vehicle with respect to the direction of travel. For any alignment of the vehicle's longitudinal direction that deviates from the direction of travel, it must be ensured that the vehicle does not protrude laterally beyond a permissible area of the road despite this inclination.

Each point on its strip can also be assigned a height available to a vehicle, so that a three-dimensional space is considered that is available to the vehicle for its journey. In the following, the determined route section is therefore synonymously referred to as a “hose”. The route section is preferably determined in such a way that the center of gravity of the vehicle is within the available width over the entire route section. Since this is based on the center of gravity of the vehicle and this center of gravity is usually inside the vehicle. The vehicle extends from this center of gravity by a known amount in all directions. This additional space required by the vehicle is preferably taken into account when calculating a route section, particularly preferably with an additional safety surcharge.

A twisting of the vehicle's longitudinal direction around a vertical axis is generally referred to as yaw. Of particular importance in vehicles is the so-called slip angle, which is usually defined as the angle between the direction of movement of the vehicle and the longitudinal axis of the vehicle about a vertical axis located at the center of gravity of the vehicle. However, the slip angle can also be specified for locations in the vehicle other than the center of gravity. Unless otherwise stated below, all information on the slip angle refers to a slip angle around a vertical axis standing on the rear axle, in particular the geometric center of the rear axle.

In a preferred method variant, an optimized vehicle alignment for future cornering is determined taking into account at least one parameter that is selected from a group that includes a direction of movement of the vehicle with respect to a lane, a position of the vehicle on a lane, and a longitudinal acceleration of the vehicle along its longitudinal direction, a vehicle speed, a curve radius, a curve curvature, a road width, a vehicle length, a vehicle width, a wheelbase, a vehicle mass, a loading condition, a weight distribution, a road condition, a weather date, traffic information, a route utilization, a number of Vehicle occupants and the seating position of the vehicle occupants. Several of the above-mentioned parameters are preferably taken into account when calculating a suitable vehicle alignment for future cornering. It is conceivable, for example, that with a smaller available roadway width, a maximum slip angle for future cornering may be less large than with a larger available roadway width.

It is also conceivable that with only one vehicle occupant, the vehicle alignment for future cornering is optimized in such a way that the acceleration forces and/or back acting on this occupant are minimized. In the case of several vehicle occupants, however, it would be advantageous to optimize the vehicle alignment for future cornering in such a way that the acceleration forces and/or back acting on these occupants on average are minimized, even if an individual vehicle occupant may experience increased acceleration forces and/or back.

A method variant has proven to be particularly advantageous, in which a slip angle of the vehicle is deflected towards the outside of the curve while driving on a first section of the curve and in the direction of the inside of the curve while driving on a second section of the curve. The first section is preferably (in each case along the direction of travel) a section lying before the apex of the curve and the second section is a section lying after the apex of the curve. This opens up the possibility of distributing parts of the (kinematic) acceleration forces that occur when cornering, which inevitably occur due to the necessary rotation of the vehicle (change in the normal vector while driving along a curved route), to these sections, where they are applied to the occupants Longitudinal and/or lateral acceleration can be perceived. Preferably, the longitudinal axis of the vehicle is disproportionately relative before entering the curve and/or at the beginning of the curve the direction of travel towards the inside of the curve. When approaching the apex - where particularly strong acceleration forces and/or particularly large gradients usually occur in the acceleration/time diagram, part of the rotation of the vehicle necessary for cornering has already been completed, so that additional accelerations (in particular) caused by the rotation are already completed Lateral accelerations) can be reduced.

Analogously, in the second section (which lies essentially after the apex of the curve with respect to the direction of travel), the vehicle's longitudinal axis is rotated disproportionately with respect to the direction of travel towards the inside of the curve. The vehicle covers the first part of this section in a driving mode similar to crab gear. Part of the rotation of the vehicle required to exit the curve is shifted to parts of the route that are in the area of the corner exit or even behind it. Perceived accelerations (particularly lateral accelerations) resulting from the rotation of the vehicle can thus be shifted from the area of the apex to areas of the route in which significantly lower acceleration forces act on the vehicle occupants.

As especially in connection with the in 6 As is described in the diagram shown, it is conceivable that at the apex the transverse acceleration (essentially caused by the centripetal force) remains essentially unchanged compared to a normal curve. Nevertheless, when carrying out the method according to the invention, the temporal change in the transverse acceleration (lateral jerk) and the change in the effective direction of the resulting acceleration acting on the passenger (vector sum of the longitudinal and transverse acceleration) are preferably reduced.

Even if the above-mentioned measures may extend the accelerations affecting the vehicle occupants over a longer period of time, this still has a positive effect on the driving comfort for the vehicle occupants, since steep gradients in the acceleration/time diagram that are perceived as unpleasant can be avoided.

Preferably, at least one, preferably several, more preferably all of the method steps described above can be carried out using a processor device and/or data processing device, using at least one (computer-implemented) calculation method. These calculations preferably also include data from (computer-implemented) perception and/or detection tasks, such as (computer-implemented) object recognition methods and/or (computer-implemented) methods for semantic segmentation and/or (computer-implemented) object classification ( “Image classification”) and/or (computer-implemented) object localization and/or (computer-implemented) edge detection. The (computer-implemented) method can be based on a machine learning model, which can use a (trained) neural network. In addition or as an alternative, a model-based optimization method can also be used

In a further preferred method, the determined and/or calculated data are preferably stored together with global position data assigned to them, determined essentially at the same time and/or subsequently, on a (preferably vehicle-internal) storage device of the vehicle.

The (vehicle-internal) storage device is preferably a ring memory.

We prefer to make at least some of the determined and/or calculated data available to other road users. In this regard, it is conceivable, for example, that following or oncoming road users are informed about the use of a certain section of the route by the ego vehicle. The data transmitted can include, for example, information about a time of use of a route section, an expected speed when using this route section, a roadway width expected to be used when using this route section, weather data, data on the road condition and others. This data can also be made available on an external storage device for other road users to access.

In a preferred method, the external storage device is a cloud-based storage device and/or an external server. An external server is understood to mean, in particular, a server that is external to the vehicle (of the user), in particular a backend server. The external server is, for example, a backend of a vehicle manufacturer or a service provider, which is set up to manage at least one date from the above selection (in particular with location data assigned to it). The functions of the backend or the external server can be carried out on (external) server farms the. The (external) server can be a distributed system. The external server and/or the backend can be cloud-based.

Optionally, it is also possible to carry out one or more steps of the method according to the invention using an external storage device and/or external computing device. It is conceivable, for example, that slip angles can be calculated by a backend server with an existing data connection to the ego vehicle.

• - Aufstellen einer Beschleunigungsfunktion in welcher eine Längs und/oder Querbeschleunigung und/oder Beschleunigungsänderung vorzugsweise gewichtet bewertet werden,
• - Minimierung der Beschleunigungsfunktion durch Veränderung eines mit einer Fahrzeugausrichtung korrelierenden Winkels mittels eines geeigneten Algorithmus, wobei vorzugsweise mindestens eine maximal zulässige (Längs und/oder Quer-) Beschleunigung unterschritten wird, und
• - Berechnen eines Schwimmwinkels des Fahrzeugs für eine Vielzahl von Zeit- und/oder Wegpunkten des Durchfahrens einer Kurve, basierend auf der minimierten Beschleunigungsfunktion.

Furthermore, the present invention relates to a method for determining slip angles to be assumed by a vehicle with a steerable front axle and a rear axle that can be steered independently of it while driving through a curve or a route section with a curvature that is at least partially non-zero. This procedure includes the steps:

• - Setting up an acceleration function in which a longitudinal and/or transverse acceleration and/or change in acceleration are preferably evaluated in a weighted manner,
• - Minimizing the acceleration function by changing an angle that correlates with a vehicle orientation using a suitable algorithm, preferably at least a maximum permissible (longitudinal and/or transverse) acceleration being undershot, and
• - Calculating a slip angle of the vehicle for a plurality of time and/or waypoints when traveling through a curve, based on the minimized acceleration function.

Regarding the acceleration function, it should be noted that the acceleration as such does not necessarily have to be a variable of this function. However, the term “acceleration function” is used in the context of this invention because at least one variable of such a function influences a (longitudinal and/or transverse) acceleration, can be used to calculate an acceleration, and/or is characteristic of an acceleration. For example, a function that characterizes a jerk is also viewed as an acceleration function, since these can be directly converted into one another as a first derivative. Analogously, functions that do not contain the acceleration itself as a function value, argument and/or variable could also be an acceleration function, provided that an acceleration can be calculated from other values of this function (for example taking into account a slip angle and/or a speed).

When minimizing the acceleration function, an angle that correlates with a vehicle orientation is preferably optimized using a suitable algorithm in such a way that the jerks acting on a vehicle occupant - i.e. the amount of the first derivative of the acceleration function - are almost minimal. “Almost minimal” should be understood in this context to mean that the minimum jerk theoretically possible for these time and/or waypoints should not be determined for each time and/or waypoint, but rather the acceleration function is optimized in such a way that this is preferred A jerk occurring at each time and/or waypoint taken into account is selected so that the sum of the jerk amounts approaches a minimum over the entire function. It is certainly possible and advantageous in some process variants if the absolute minimum is not achieved. This is particularly the case if the absolute minimum can only be achieved if there is a jerk at at least one time and/or waypoint that could be perceived as particularly disturbing by a vehicle occupant.

A method has proven to be particularly suitable in which the acceleration function is a quality function or cost function. A cost function preferably offers the possibility of weighting the longitudinal and/or lateral acceleration.

The minimization of the cost function by changing at least one variable characterizing a vehicle orientation is preferably carried out using a suitable algorithm. Alternatively or in addition, the minimization can be carried out using machine learning and/or model-based optimization and/or other preferably computer-implemented methods.

Preferably, longitudinal and lateral acceleration are weighted in the acceleration function or cost function. Preferably, the weighted longitudinal and lateral acceleration are penalized, preferably when an individual value or one or more of their sums exceeds a limit value.

In particular, it is preferred that returns are weighted and/or penalized in the acceleration function or cost function, preferably if an individual value or one or more of their sums exceeds a limit value.

The acceleration function and/or cost function is preferably minimized by changing at least one driving function variable characterizing the tool alignment. If such a minimization does not provide an acceptable solution, a further minimization can be carried out by changing at least one further variable, such as a variable characteristic of a vehicle speed.

In one method variant, a maximum permissible (longitudinal and/or transverse) acceleration and/or a (longitudinal and/or transverse) jerk is selected so that it is not perceived as disturbing for the vehicle occupant. Since this feeling can be different for different vehicle occupants, it can preferably be selected individually. If necessary, you can also choose between different modes that allow different maximum permissible accelerations. For example, a rest or sleep mode would be conceivable, which allows a particularly low maximum permissible acceleration, whereas, for example, an awake, conversation or meeting mode allows a higher maximum permissible acceleration. A travel time-optimized mode would also be conceivable, in which an even higher maximum permissible acceleration is permitted and the vehicle's side slip angles when driving through a curve are optimized to ensure that the vehicle can be driven through the curve as quickly as possible.

The method described above is preferably carried out by a vehicle-mounted processor device. This makes it possible, individually for this vehicle - if necessary taking into account fixed vehicle parameters (such as dimensions of the vehicle) and / or variable parameters (such as loading status, weather conditions, traffic density, vehicle load, road condition) - to make it possible for the occupants to drive through curves with this vehicle in a comfortable manner becomes.

Optionally, for each slip angle calculated as above, an angle of the steerable front axle and the steerable rear axle of the vehicle necessary to adjust the slip angle is also calculated. This can be done at a time and location offset from the determination of the slip angle described above. This calculation is preferably carried out while cornering. A dedicated calculation of the required angle of the steerable axles can be omitted if the vehicle offers the possibility of measuring a current float angle and comparing this with a target float angle specified for this route position and adjusting the angle of the steerable axles accordingly to compensate for any deviations that may exist adjust in real time.

With regard to this method for determining the slip angles to be adopted by a vehicle while driving through a curve, the statements made above regarding the previously described method for increasing driving comfort also apply. Conversely, the method for increasing driving comfort can be carried out individually or in combination with all of the slip angles to be assumed by a vehicle while driving through a curve. Thus, the respective method as well as individual preferred embodiments also represent preferred embodiments of the other method. For example, for the method for determining slip angles to be assumed by a vehicle while driving through a curve, it is also preferred that at least one, preferably several, is further preferred all of the method steps described above are carried out using a processor device and / or data processing device, using at least one (computer-implemented) calculation method (with all preferred embodiments), as disclosed for the method for increasing driving comfort.

• - ein Navigationssystem zur Ermittlung eines von dem Fahrzeug zukünftig befahrbaren Streckenabschnitts, wobei dieser Streckenabschnitt mindestens eine Kurve einschließt,
• - eine Prozessoreinrichtung, welche zur Berechnung eines geeigneten Schwimmwinkels für eine Vielzahl von Wegpunkten in dem Streckenabschnitt vorgesehen und eingerichtet ist, und
• - einen Aktuator mittels welcher der Einschlag der vorderen und/oder der hinteren Achse derart einstellbar ist, dass das Fahrzeug zu jedem an jedem der Wegpunkte den von der Prozessoreinrichtung für diesen Wegpunkt vorberechneten Schwimmwinkel einnimmt,

dadurch gekennzeichnet, dass das Vorzeichens des Winkels des Einschlags der hinteren Achse bezüglich der Fahrzeuglängsachse in einem ersten Abschnitts der Kurve anders ist als in einem zweiten Abschnitts der Kurve. Eine solche Vorrichtung erlaubt es Beschleunigungsspitzen und insbesondere große Steigungen in einem Beschleunigungs-Zeit-Diagramm zu vermeiden.Furthermore, the object on which the invention is based is achieved by a device for increasing driving comfort for occupants of an at least partially autonomous vehicle with at least one steerable front axle and a rear axle that can be steered independently of it. This device includes

• - a navigation system for determining a section of route that can be traveled by the vehicle in the future, this section of route including at least one curve,
• - a processor device which is provided and set up to calculate a suitable slip angle for a large number of waypoints in the route section, and
• - an actuator by means of which the angle of the front and/or rear axle can be adjusted in such a way that the vehicle assumes the slip angle pre-calculated by the processor device for this waypoint at each of the waypoints,

characterized in that the sign of the angle of the angle of the rear axle with respect to the vehicle's longitudinal axis is different in a first section of the curve than in a second section of the curve. Such a device allows acceleration peaks and in particular large gradients to be avoided in an acceleration-time diagram.

In particular, this can be achieved in that the slip angle of the vehicle is deflected in the first section of the curve relative to the direction of travel of the vehicle towards the inside of the curve and in a second section of the curve in the direction of the outside of the curve. Acceleration peaks that occur particularly in the area of the apex of the curve can be avoided and acceleration components caused by the rotation of the vehicle can be shifted to other sections of the route.

Preferably, the first section is a section lying along the direction of travel before the apex of the curve and the second section is a section lying after the apex of the curve. This makes it possible for the vehicle to complete the entire change of direction specified by the curve, but at least parts of the rotation required for this take place in sections of the route in which the burden on the vehicle occupants due to further acceleration forces is low.

A device has proven to be particularly preferred in which the angle of the turning of the rear axle with respect to the vehicle's longitudinal axis in the area of an apex of the curve is ≤ ± 2°, preferably ≤ ± 1°, more preferably ≤ ± 0.5° and particularly preferred is essentially zero. In this context, lying in the area of the apex should be understood to mean a section of route which is preferably within a distance of ≤ ± 20 m, preferably ≤ ± 10 m, more preferably ≤ ± 5 m and particularly preferably ≤ ± 3 m from the apex of the curve or encompasses the vertex. With this configuration it can be achieved that no torque is triggered on the vehicle, at least by the rear axle. In particular, a drift-like condition can be avoided in which the vehicle oversteers and which could be perceived as particularly unpleasant by vehicle occupants due to the acceleration peak that occurs.

As described above, a device according to the invention comprises at least one actuator for adjusting a steering angle of the front and/or rear axle. Such an actuator is also known as a steering actuator. By means of such a steering actuator, an angle of at least a selection of vehicle tires can be adjusted relative to a longitudinal direction of the vehicle (vehicle longitudinal direction). For example, it is conceivable that the steering actuator adjusts the turning of two front wheels of a vehicle together. This can be done, for example, by moving a steering lever and/or tie rods. However, it is also conceivable that the turning of one or each individual wheel with respect to the vehicle's longitudinal direction can be adjusted using a separate actuator. As a result, the setting of a deflection of one or more tires can be carried out independently of the adjustment of the deflection of one or more other tires.

In general, in the context of this invention, the impact of the front and/or rear axle should be understood to mean that the angle of at least one wheel connected to this axle is changed relative to the longitudinal axis of the vehicle.

In the context of this invention, the term “tire” is understood in its usual meaning, namely as that part of a wheel on which the wheel rolls. The tire usually forms the circumference of the wheel and transfers the forces between the wheel and the road. However, the terms wheel and tire are used synonymously in connection with this invention.

However, the term “tire” should not be understood in isolation, particularly in connection with an “impact” of a vehicle tire. As described above, it is common for the tire to be part of a wheel. Accordingly, the impact of the tire does not occur in isolation, but usually together with other parts of the vehicle such as the wheel and/or parts of the steering mechanism and/or the axle or wheel suspension. Unless it is explicitly stated that the tire is viewed in isolation, parts associated with it, in particular the remaining parts of the wheel, are also to be understood.

Preferably, the device comprises a control device by means of which a signal corresponding to the angle of a steerable axle provided by the processor device and/or the slip angle can be implemented. This signal includes information about a target impact of at least a selection of vehicle tires. For example, the control device can generate a signal which contains information about the desired angle of the front tires on the one hand and the rear tires of a vehicle on the other hand. This signal is converted by the steering actuator of the affected axle into a turning of the relevant tire or tires with respect to the longitudinal direction of the vehicle. The control device can be a mechanical transmission or an electronic control device. The signal can accordingly (but independently) be an electrical signal or a mechanical impulse such as an acceleration of a steering lever.

The device preferably includes sensors that record safety-relevant vehicle data sen. In particular, it is preferred that the mode with increased driving comfort for the vehicle occupants is exited if indications of an unsafe traffic situation can be derived from the data of one or more sensors.

In a preferred embodiment, the device comprises at least one yaw sensor, by means of which a rotation of the vehicle about its yaw axis (also referred to as the vertical or vertical axis of a coordinate system fixed to the vehicle). This rotation about the yaw axis can be used by the processor device to calculate the slip angle (rear axle) using additional vehicle data (for example position of the yaw sensor in the vehicle, dimensions of the vehicle, direction of movement of the vehicle, orientation of the yaw sensor with respect to the vehicle's longitudinal axis and others). If a deviation from the specified slip angle is detected by the yaw sensor, an exit from the mode with increased driving comfort can be triggered - if necessary.

Preferably, a deviation of the target float angle from the actual float angle can be detected (for example, taking data from the yaw sensor into account). If necessary, the processor device can generate a correction signal by means of which this deviation can be corrected. In particular, when calculating a correction signal, vehicle data is included in the calculation of a turn of the front axle and / or rear axle, which is selected from a group that includes the vehicle speed, curve radius, distance of the vehicle from one or more road boundaries, distance of the vehicle from one or more others Vehicles, outside temperature, tire temperature, tire pressure, yaw, acceleration, longitudinal acceleration, lateral acceleration, drift, road moisture, air humidity, current amount of precipitation, amount of precipitation in a defined previous period, weight of the vehicle, payload of the vehicle and the center of gravity of the vehicle. By taking data from this group into account, any deviation of the target float angle from the actual float angle can be corrected and ensure that the vehicle is always in a safe driving condition.

In a preferred embodiment, the computer device is connected to a data processing device arranged outside the vehicle. Such a data connection makes it possible to use data to calculate the target float angle that is not available or determined in the vehicle itself. This data can be, for example, traffic information or weather data.

Furthermore, the present invention is directed to a vehicle, in particular a motor vehicle, which comprises a device as described above for increasing driving comfort for occupants. In such a vehicle, the acceleration forces and/or jerks acting on the occupants when cornering are reduced compared to vehicles without such a device (and/or without additional rear axle steering). Particularly in the case of autonomous vehicles, this offers the possibility of avoiding distractions for the vehicle occupants due to accelerations (or jerks) that occur unexpectedly for them. This is particularly advantageous during long journeys at high speeds, such as when traveling on a motorway. Motorways also usually offer a sufficiently large roadway width, which makes it possible to twist the vehicle at a calculated slip angle with respect to the roadway direction, without causing any impairment to vehicles on other lanes. However, the present invention also offers advantages when driving over winding routes such as country roads or in the city. When carrying out the procedure, a sufficient safety distance must be ensured in these comparatively narrow available lanes.

The device is preferably set up, suitable and/or intended to carry out the method described above as well as all method steps described in connection with the method individually or in combination with one another or individual method steps using the method. Conversely, the method for increasing driving comfort for occupants can be carried out individually or in combination with all of the features described in the context of the device.

The present invention is further directed to a vehicle, in particular a motor vehicle, comprising a device described above for increasing driving comfort according to an embodiment and/or to a vehicle which is suitable for carrying out a method as described above.

The vehicle can in particular be a (motorized) road vehicle. The vehicle can be, for example, a passenger car (car), a truck (lorry) or a bus.

A vehicle can be a motor vehicle, which is in particular a semi-autonomous, autonomous (for example autonomy level level 3 or 4 or 5 (the SAE J3016 standard)) or self-driving motor vehicle. The autonomy level level 5 refers to fully automated vehicles. The vehicle can also be a driverless transport system.

The present invention is further directed to a system comprising at least one (and preferably a plurality) of device(s) described above for (each) a vehicle according to an embodiment and comprising an external storage device and/or an external server or a backend corresponding to an embodiment described above. The external storage device or the backend preferably receives information from a large number of (different) vehicles (which were determined and/or generated by their device(s)) and is preferably suitable and intended to combine these into an (even larger) database .

The present invention is further directed to a computer program or computer program product, comprising program means, in particular a program code, which represents or encodes at least individual and preferably several method steps (individually or in combination with each other) of the method according to the invention and preferably one of the preferred embodiments described and for execution a processor device is formed.

The present invention is further directed to a data memory on which at least one embodiment of the computer program according to the invention or a preferred embodiment of the computer program is stored.

Further advantages and embodiments result from the attached drawings:

• 1 eine schematische Darstellung eines Fahrzeugs in einem ersten Zustand und kleinem Schwimmwinkel;
• 2 eine schematische Darstellung eines Fahrzeugs in einem zweiten Zustand und gegenüber dem in 1 dargestelltem Schwimmwinkel größeren Schwimmwinkel;
• 3 eine schematische Darstellung eines Fahrzeugs in einem dritten Zustand und gegenüber dem in 2 dargestelltem Schwimmwinkel nochmals vergrößertem Schwimmwinkel;
• 4 eine schematische Darstellung der Ausrichtung eines Fahrzeugs bei einer Kurvenfahrt in einer Ausführungsform der vorliegenden Erfindung; und
• 5, 6 jeweils eine Grafik zum Vergleich der auf einen Fahrzeuginsassen wirkenden Längs- (5) und Quer- (6) Beschleunigungskräfte bei konventioneller Kurvenfahrt und gemäß der vorliegenden Erfindung.

Show in it:

• 1 a schematic representation of a vehicle in a first state and a small slip angle;
• 2 a schematic representation of a vehicle in a second state and compared to the one in 1 shown slip angle larger slip angle;
• 3 a schematic representation of a vehicle in a third state and compared to the one in 2 shown slip angle again enlarged slip angle;
• 4 a schematic representation of the orientation of a vehicle when cornering in an embodiment of the present invention; and
• 5 , 6 one graphic each to compare the longitudinal ( 5 ) and transverse ( 6 ) Acceleration forces during conventional cornering and according to the present invention.

1 shows a schematic representation of a vehicle 1 in a first state and a small slip angle. The vehicle 1 is equipped with a system according to the invention. For clarity, only the tires 2, 4 are shown, with the front tires 2 turned in pairs to the left. The rear tires 4 are not wrapped in the state shown. Due to the impact of the front tires 2, the vehicle 1 is deflected relative to the previous direction of travel indicated by the arrow P, which corresponds to the longitudinal direction of the vehicle, and then follows a curve K. In an ideal system (and/or low speed), the side slip angle would be zero, since the vehicle follows the direction of the front wheels 2 and the direction of travel would correspond to the circular path K. In real systems, however, a non-negligible slip angle usually occurs (at least at higher speeds) even in such a state, since due to friction losses in the area of the contact surface of the tires 2, 4 with the road, the lateral forces acting on the wheels lead to a slip angle. This is also commonly referred to as side slip and/or tire slip angle.

Like especially in connection with 4 described occurs as in 1 The state shown occurs, for example, before entering the curve and / or in the area of the apex of the curve.

2 shows a schematic representation of a vehicle 2 in a second state and compared to that in 1 shown slip angle larger slip angle β. The slip angle β is in 2 shown as an angle between the force vector F _ZP , which is perpendicular to the direction of travel P, and the vehicle's transverse axis, but corresponds in magnitude to the angle between the vehicle's longitudinal direction and the direction of travel P at the center of gravity of the vehicle. Different than in 2 Unless otherwise stated, the slip angle β is shown not at the center of gravity but, deviating from this usual definition, at (the geometric center) of the rear axle.

At the in 2 In the example shown, both the wheels 2 of the front axle and the wheels 4 of the rear axle are turned in the same direction relative to the longitudinal direction of the vehicle. To set a desired slip angle β, the amount of the angle chosen can differ. If the amount of the turned angle on the rear wheels 4 is greater than on the front wheels 2, the slip angle β increases; if it is smaller, the slip angle β decreases. If the front wheels 2 and rear wheels 4 are turned at the same angle relative to the longitudinal direction of the vehicle, the side slip angle β remains constant and the vehicle 1 moves in crab gear. At the in 2 In the example shown, the rear wheels 4 are turned at a slightly smaller angle compared to the longitudinal direction of the vehicle, so that the side slip angle β is reduced. Such a condition is related to 4 described in more detail and can preferably be present after driving over the area of the apex of the curve.

3 shows a schematic representation of a vehicle 1 in a third state and compared to that in 2 shown slip angle β again enlarged slip angle β. A as in 3 The state shown will usually not occur when implementing the method according to the invention. Nevertheless, the representation of this state shows how forces acting on the occupants of the vehicle 1 can be changed while cornering. Due to the extremely large slip angle β of almost 90° in this state, the centrifugal force acting on the vehicle occupants is almost completely transformed from a force acting transversely when cornering conventionally into a force acting in the longitudinal direction of the vehicle. At such a slip angle, a vehicle occupant is pushed into a seat by the centrifugal force. There is no acceleration of the vehicle occupants along the transverse direction of the vehicle. As explained above, in such a third state a particularly effective conversion of a (kinetic) tangential acceleration into a (perceived) transverse acceleration acting on an occupant is possible.

4 shows a schematic representation of the orientation of a vehicle 1 at various positions that it assumes while cornering according to an embodiment of the present invention. The navigation system of the vehicle 1 has determined a suitable tube or strip S for a section of route that the vehicle can drive in the future. This section of the route has (at least) one curve. The center of gravity of the vehicle 1, which is only shown schematically, can occupy any position within the strip S. The center of gravity can approach the lateral boundaries of this strip. Since the strip is available to the vehicle's center of gravity, this means that portions of the vehicle can even be located outside the strip at times. This is, for example, at the positions marked P ₂ and P ₃ in 4 the case.

In the example shown, a vehicle 1 approaches the curve from the bottom right. The vehicle has a front side V and a rear side H and initially moves along its longitudinal direction along the route Fs along the strip S towards the curve. The center of gravity of the vehicle initially follows almost a straight line (even if the calculated strip has a slight S-shape). This route results in particularly low kinematic (lateral) accelerations that affect the vehicle occupants.

In the example shown, a rotation of the vehicle is already initiated in a section in which the vehicle 1 follows an almost straight path FS. The rotation begins approximately at the point marked _P1 . It can be triggered by appropriately controlling the actuators to turn the axles or wheels 2, 4. At times there is a situation like this 1 shown conceivable. This turning of the wheels 2, 4 creates a slip angle. The front V of the vehicle turns towards the inside of the curve. The vehicle can also be braked during this process. However, due to the comparatively long section of road available to the vehicle 1 for these maneuvers, the jerk acting on the vehicle occupants can be kept low at any time - in particular through a favorable distribution of the acceleration that occurs into resulting vectors of longitudinal and transverse accelerations.

Before the vehicle enters the curve, it has a large slip angle β. Due to the curved course of the road in the area of the curve and thus also of the route Fs, the longitudinal direction of the route approaches the longitudinal direction of the vehicle in the course of the curve. The slip angle β therefore decreases. In the area of the apex, the slip angle β is preferably almost zero. This condition occurs along the route before the point marked P2. In point could preferably again be one of the representation in 1 appropriate vehicle condition is present.

In the point marked P ₂ there is a comparatively strong curvature of the strip S. The curvature of the path F _S is Although somewhat smaller due to the use of the entire width of the strip S, high accelerations are still to be expected at this point, which affect the vehicle occupants. In order to reduce this, rotation of the vehicle is delayed and a slip angle β is built up. The vehicle 1 does not follow the rotation predetermined by the curvature of the route Fs completely, but rather with a delay. The front of the vehicle V is aligned towards the outside of the curve.

The slip angle β has a different sign compared to the curve entry described above.

The reduction of the slip angle β (preferably to zero) can be delayed over a comparatively long period of time depending on the course of the section of route following the curve. If - as in the example shown - there is enough distance available until the next curve, the slip angle β can be reduced slowly, so that no strong acceleration forces act on the vehicle occupants during the movement in the direction R _A. At the point marked P ₃ , the reduction of the slip angle β to the value zero was already completed and an increase in the slip angle β in preparation for entering a curve (apex not shown) that follows in the section of the track has begun.

The 5 and 6 each show a graphic to compare the longitudinal ( 5 ) and transverse ( 6 ) Acceleration forces during conventional cornering 12, 22 and a method according to an exemplary embodiment of the present invention 10, 20.

The distance s traveled by vehicle 1 is shown on the abscissa axis 4 plotted in meters. The point P corresponds to ₁ 4 a distance traveled of 800 m, the point P ₂ a distance traveled of 900 m and the point P ₃ a distance traveled of 1000 m. The at each point of the in 4 shown route Fs acting on a vehicle occupant longitudinal ( 5 ) and transverse ( 6 ) Acceleration forces are plotted on the ordinate axis. The solid line 12, 22 represents the comparative example of conventional cornering and the broken line represents an example of cornering according to an exemplary embodiment according to the present invention.

The 5 It can be seen that when cornering in a conventional manner, comparatively strong negative and positive accelerations act on the vehicle occupants in the longitudinal direction of the vehicle. These forces are based on braking (negative longitudinal acceleration) before the curve and accelerating (positive longitudinal acceleration) after driving over the apex of the curve from a point that is preferably slightly before point _P2 with respect to the direction of travel.

In contrast, the accelerations acting on the vehicle occupants in the longitudinal direction of the vehicle when cornering according to a method according to an exemplary embodiment of the present invention are significantly lower, both in terms of magnitude and in gradient. This is based in particular on the fact that part of the (negative or positive) acceleration of the vehicle along the route Fs is converted from a longitudinal acceleration into a lateral acceleration by the rotation of the vehicle. The maximum acceleration acting on a vehicle occupant in the longitudinal direction of the vehicle can thus be reduced both during braking of the vehicle and during acceleration. This also has a beneficial effect on the slope of the in 5 curve shown. When carrying out the process according to the present invention, the steep gradients that most occupants find particularly annoying can be avoided.

Likewise, the advantage of the present invention extends to driving comfort 6 clearly. Negative values represent acceleration to the right in the direction of travel, positive values represent acceleration to the left. In the area between points P ₁ and P ₂ it can be seen that, unlike in conventional cornering 22, no (negative) acceleration to the left occurs because the road is not strictly followed, but the width of the calculated strip S is used to reduce it of the effective accelerations is used. Strictly following the slightly S-shaped route can be avoided.

It can also be seen that the magnitude of the lateral acceleration (as a sum across all points on the route) is greater than during conventional cornering. This results from the fact that the total amount (Euclidean norm) of kinematic and perceived acceleration must be the same. However, the variant of the method optimizes their distribution over the entire route and/or between lateral and longitudinal acceleration.

Furthermore, the early turning of the vehicle's longitudinal axis into the curve and the associated formation of the slip angle β contributes to the fact that the vehicle occupants are affected constant lateral acceleration always remains in the positive range. The rotation causes the same as above 5 describe a part of the longitudinal acceleration converted into a lateral acceleration. This means that the effective lateral acceleration increases extremely gently until it reaches its maximum at the apex of the curve.

Since the slip angle at this point is preferably almost zero and the vehicle therefore has a driving position essentially analogous to conventional cornering, the transverse accelerations acting at this point are very similar in magnitude. Nevertheless, driving through a curve according to a variant according to the present invention is perceived as significantly less disturbing by the vehicle occupants, since the maximum gradient of the in 6 Curve 20 shown is significantly lower than that of comparison curve 22. The lower gradient can also be achieved in the area between points P2 and P3, since here too part of the acceleration of the vehicle along the route Fs is not perceived as longitudinal acceleration but also due to the Rotation of the vehicle's longitudinal axis present in this section of the route as (positive) lateral acceleration. The rapid drop in lateral acceleration to zero or even below when the vehicle accelerates out of the curve, which occurs during conventional cornering, can be avoided. Accordingly, curve 20, unlike curve 22, does not have any of the sign changes in the lateral acceleration that are perceived as particularly disturbing.

The applicant reserves the right to claim all features disclosed in the application documents as essential to the invention, provided that they, individually or in combination, are new compared to the prior art. It should also be noted that the individual figures also describe features that can be advantageous in themselves. The person skilled in the art immediately recognizes that a specific feature described in a figure can be advantageous even without adopting further features from this figure. Furthermore, the person skilled in the art will recognize that advantages can also arise from a combination of several features shown in individual or different figures.

Reference symbol list

1

vehicle

2

Front wheels, front axle

4

Rear wheels, rear axle

10

Longitudinal acceleration according to an exemplary embodiment

12

Longitudinal acceleration during conventional cornering

20

Lateral acceleration according to an exemplary embodiment

22

Lateral acceleration during conventional cornering

β

Slip angle

P

Arrow, direction of travel

FZP

centripetal force

H

Rear vehicle area

v

Front area of the vehicle

RE

Direction (entering a curve)

R.A

Direction (exit from curve)

S

Tube, track, strip

P1, P2, P3

Points

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102015212229 B4 [0006]
• DE 102018220575 A1 [0008, 0009]
• DE 102017001449 A1 [0009]

Claims (10)

Method for increasing driving comfort for occupants of an at least partially autonomous vehicle (1) with at least one steerable front axle (2) and a rear axle (4) that can be steered independently thereof, comprising the steps: - Determining a route section (S) to be traveled by the vehicle (1) in the future using a navigation system, - Determining an optimized slip angle (β) for future cornering by a processor device, - Controlling an actuator for setting a deflection of the front and/or rear axle (2, 4) for corner entry in accordance with the optimized slip angle (β) pre-calculated by the processor device, - Controlling an actuator for setting a turning angle of the front and/or rear axle (2, 4) for exiting a curve in accordance with the optimized slip angle (β) pre-calculated by the processor device, and - Changing the sign of the angle of the rear axle (4) with respect to the vehicle's longitudinal axis at least once while driving through a curve. Procedure according to Claim 1 , characterized in that the control of the actuator for setting a turning of the front and/or the rear axle (2, 4) for entering a curve takes place before the vehicle (1) enters the curve and/or the sign of the angle of the turning the rear axle (4) is maintained at least temporarily with respect to the vehicle's longitudinal axis after the vehicle (1) exits the curve. Procedure according to Claim 1 or 2 , characterized in that determining a route section (S) to be traveled by the vehicle (1) in the future includes taking into account a width of the available route section (S), preferably the center of gravity of the vehicle over the entire route section (S) within the available width. Method according to one of the preceding claims, characterized in that determining an optimized vehicle orientation for future cornering takes into account at least one parameter which is selected from a group that includes a vehicle speed, a curve radius, a curve curvature, a road width, a vehicle length, a vehicle width, a wheelbase, a vehicle mass, a loading condition, a weight distribution, a road condition, a weather date, traffic information, route utilization, a number of vehicle occupants and the seating position of the vehicle occupants. Method according to one of the preceding claims, characterized in that a slip angle (β) of the vehicle is deflected towards the inside of the curve compared to the direction of travel (P) of the vehicle (1) while driving on a first section of the curve and while driving on a second section the curve in the direction of the outside of the curve, preferably the first section being a section lying before the apex of the curve and the second section being a section lying after the apex of the curve. Method for determining slip angles (β) to be assumed while driving through a curve by a vehicle (1) with a steerable front axle (2) and a rear axle (4) that can be steered independently thereof, comprising the steps: - Setting up an acceleration function in which longitudinal and/or transverse acceleration and/or longitudinal and/or transverse jerk are preferably weighted, - Minimizing the acceleration function by changing an angle that correlates with a vehicle orientation using a suitable algorithm, preferably at least one maximum permissible acceleration and / or change in acceleration being undershot, and - Calculating a slip angle (β) of the vehicle (1) for a plurality of time and/or waypoints when driving through a curve, based on the minimized acceleration function, and optionally - Calculating an angle of the steerable front axle (2) and the steerable rear axle (4) of the vehicle (1) necessary to adjust the slip angle (β). Device for increasing the driving comfort for occupants of an at least partially autonomous vehicle (1) with at least one steerable front axle (2) and a rear axle (4) that can be steered independently thereof, comprising - a navigation system for determining a route section that can be traveled by the vehicle (1) in the future ( S), wherein this route section (S) includes at least one curve, - a processor device which is provided for calculating a suitable slip angle (β) for a large number of waypoints (P ₁ , P ₂ , P ₃ ) in the route section (S) and is set up, and - an actuator by means of which the angle of the front and / or rear axle (2, 4) can be adjusted such that the vehicle (1) is at each of the Waypoints (P ₁ , P ₂ , P ₃ ) assumes the optimized float angle (β) precalculated by the processor device for this waypoint (P ₁ , P ₂ , P ₃ ), characterized in that the sign of the angle of the angle of the rear axle ( 4) is different with respect to the vehicle's longitudinal axis in a first section of the curve than in a second section of the curve. Device according to Claim 7 , characterized in that the slip angle (β) of the vehicle (1) is deflected in the first section of the curve in the direction of the inside of the curve relative to the direction of travel of the vehicle (1) and in a second section of the curve in the direction of the outside of the curve, preferably the first section is a section lying along the direction of travel before the apex of the curve and the second section is a section lying after the apex of the curve. Device according to Claim 7 or 8th , characterized in that the angle of the turning of the rear axle (4) with respect to the vehicle's longitudinal axis in the area of a vertex of the curve is ≤ ± 2°, preferably ≤ ± 1°, more preferably ≤ ± 0.5° and particularly preferably essentially the same is zero. Vehicle comprising a device according to one of the Claims 7 - 9 and/or a processor device for carrying out a method according to one of Claims 1 - 6 .

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