DE102023206116A1 - Device for operating a motor vehicle and motor vehicle - Google Patents

Abstract

Device for operating a motor vehicle, comprising a model-predictive driving operation module which is designed to model-predictively generate a driving signal for the motor vehicle depending on a first driving specification, a second driving specification and a motor vehicle specification, wherein the first driving specification is a speed specification of a driver, wherein the second driving specification is a speed range specification of the driver and wherein the motor vehicle specification is a speed deviation specification and a control module which is designed to control the motor vehicle based on the generated driving signal.

Description

The present disclosure relates to a device for operating a motor vehicle and a motor vehicle with such a device.

Today's driving operation modules generate driving signals for operating a motor vehicle predominantly on a rule-based basis.

It is therefore an object to provide an improved device for operating a motor vehicle.

This problem is solved by the subject matter of the independent claims. Further developments are specified in the dependent claims.

According to a first aspect, a device for operating a motor vehicle is provided.

The device comprises a model-predictive driving operation module which is designed to model-predictively generate a driving signal for the motor vehicle depending on a first driving specification, a second driving specification and a motor vehicle specification, wherein the first driving specification is a speed specification of a driver, wherein the second driving specification is a speed range specification of the driver and wherein the motor vehicle specification is a speed deviation specification, and a control module which is designed to control the motor vehicle based on the generated driving signal.

In particular, the device uses a speed specification and a speed range specification from the driver to generate driving signals for operation of the motor vehicle in a model-predictive manner.

The modules of the device described in more detail below are in particular software-based and are implemented, for example, by executing certain program data from a computing unit.

For this purpose, the device has a model-predictive driving operation module which is designed to model-predictively generate a driving signal for the motor vehicle depending on a first driving specification, a second driving specification and a motor vehicle specification, wherein the first driving specification is a speed specification of a driver, wherein the second driving specification is a speed range specification of the driver and wherein the motor vehicle specification is a speed deviation specification.

The driving operation module is a module that fulfills or supports a specific driving function, in particular a longitudinal control function, of the motor vehicle.

For example, one driving function is a speed control function, which can also be referred to as cruise control. This speed control function maintains a certain speed without the driver having to actively operate a drive or brake.

Another example is a distance control function, which can also be referred to as distance control. This distance control function maintains a certain distance from a vehicle in front without the driver having to actively operate a drive or brake.

For example, one driving function is a curve holding function, which can also be referred to as a curve assistant. This curve holding function follows a curve or road layout and adjusts the speed to the curve radius without the driver having to actively operate a drive or brake.

These driving functions can also be collectively referred to as adaptive cruise control (ACC), whereby the driving mode module fulfils at least one or more sub-functions.

The driving instructions initially include instructions from a driver, namely a speed setting and a speed range setting. The speed is the speed that the speed control function should maintain. The speed range setting This is a speed band within which the speed can or may be deviated from. For example, the speed setting is a speed of 100 km/h and the speed band setting is a band of +/- 10 km/h. This means that the driving signal for the motor vehicle is generated in the range of 100 km/h +/- 10 km/h or causes operation in this range.

In addition to the driving instructions, a vehicle instruction is also taken into account, which concerns a speed deviation instruction. This vehicle instruction cannot be influenced by the driver, but is a instruction from the vehicle manufacturer as to how much the speed instruction may be deviated from within the speed band and in the respective driving mode, whereby the deviation continues to occur exclusively within the speed band.

The speed deviation specification is therefore particularly dependent on the speed specification and the driving mode, both of which are selected by the driver, although the deviation itself cannot be set by the driver but is preset. For example, a higher deviation from the speed is permitted or enabled with a higher speed specification than with a lower speed specification.

In addition, other specifications can also be taken into account, such as legal requirements that, for example, specify a prescribed minimum distance that the distance keeping function must maintain.

In this case, model predictive particularly includes the fact that statements can be made about the future behavior of a system, in this case the motor vehicle, based on a model based on restrictions and/or goals to be achieved. In particular, model predictive does not mean rule-based. Model predictive control (MPC) in this case particularly includes model-based and optimization-based control. In particular, it involves the solution of dynamic optimization problems with an objective function and restrictions, which are solved, for example, using an optimizer, in particular gradient-based.

For this purpose, the model predictive driving module has access to one or more sensors and/or one or more pieces of information stored in a memory.

For example, the driving operation module can access one or more environmental sensors, one or more map information and/or one or more driving operation sensors.

In particular, the driving operation module has access to one or more camera devices, one or more lidar devices and/or one or more radar devices that are arranged on or in the motor vehicle. These sensors can also be summarized under the term perception sensors. In particular, the driving operation module also has access to one or more storage devices in which map information is stored and which are arranged on or in the motor vehicle. In particular, the driving operation module also has access to one or more driving operation sensors, such as one or more speed sensors and/or acceleration sensors.

The driving signal can include instructions or information from which the controller or a control module can control the motor vehicle. In particular, the driving signal includes a signal that indicates an acceleration and/or one or more moments or from which an acceleration and/or one or more moments can be derived.

The torque signal can comprise a braking torque signal, i.e. a specific braking torque to be achieved, and/or a driving torque signal, i.e. a specific driving torque to be achieved. The driving torque can also be referred to as traction torque. In particular, the driving signal can comprise several driving torque signals, for example one for an internal combustion engine and one for an electric machine. The driving torque signal can also assume negative values, which are then interpreted as a recuperation signal from the electric machine. The driving signals generated thus comprise several signals, for example in the form of a driving signal vector.

The device also comprises a control module configured to control the motor vehicle based on the generated driving signal.

For this purpose, the control module can have access to one or more actuators of the motor vehicle, in particular one or more of an acceleration actuator and/or a brake actuator, which cause an acceleration and/or braking actuation of the motor vehicle.

This device makes it possible to generate driving signals for the operation of the motor vehicle in advance. In particular, the device makes it possible to generate the driving signals not only based on a speed specification but also based on a speed range specification, which enables a particularly comfortable journey.

According to a further development, the model predictive driving operation module is further designed to generate the acceleration signal based on a third driving specification, wherein the third driving specification is a driving mode specification of the driver.

A driver's driving mode specification is a specification that relates to a driving or operating mode of the motor vehicle. In particular, the motor vehicle has several preset driving modes from which the driver can select one.

For example, the motor vehicle has a sporty driving mode, in which in particular a travel time of the motor vehicle is optimized, and an energy-efficient driving mode, in which in particular energy saving is optimized.

Optional driving modes can also be provided, for example a balanced driving mode that strikes a balance between travel time and energy savings.

This training enables the driver to operate the vehicle in different driving modes. This enables particularly user-friendly operation.

According to a further development, the model predictive driving operation module is designed to generate the driving signal based on topography information.

As described above, the driving operation module can have access to one or more sensors and/or one or more pieces of information.

The information can in particular include map information, which includes, for example, curve information and in particular topography information. Topography information in particular includes information about the earth's surface or the terrain along a route of the motor vehicle. In particular, the topography information includes information about an incline and/or a decline along the route.

The model predictive driving operation module is designed to generate the driving signal based on this topography information, among other things. The model predictive driving operation module can of course use or evaluate further information and sensor data to generate the driving signal.

This further development makes it possible to generate particularly predictive driving signals.

According to a further development, the model predictive driving operation module minimizes a cost function.

In particular, the driving operation module solves the cost function taking into account the speed specification and the speed range specified by the driver. The cost function will be explained in more detail later.

This further development makes it possible to generate particularly predictive driving signals.

According to a further development, the cost function takes into account the energy present in an energy storage device of the motor vehicle, a deviation from the speed specification and/or an elapsed time.

The cost function can give different weights to the energy available in the motor vehicle's energy storage device, the deviation from the speed specification and/or the elapsed time.

In particular, the cost function is defined as follows: $$J\left(x,u,\delta \right)={\displaystyle \sum _{k=1}^N\left(w_E{E}_{Storage}\left(x_k\right)+w_{set}{e}_{set}\left(x_k\right)+{\varphi }_j\left(x_k,{\delta }_k\right)+{\varphi }_a\left(x_k,{\delta }_k\right)+w_{ith}{\delta }_{ith}+w_{uth}{\delta }_{uth}\right)+w_t}t$$

Where E _Storage is the energy available in the vehicle's energy storage, e _{set is} the deviation from the speed setting and t is the time elapsed. The associated weights are w _E , w _set and w _t , which reflect or take into account the driving mode setting. The factor w _t is a value that depends on both the driving mode and the speed setting or has different weighting values for different driving modes and different speed settings. The other factors designated with w are also weights.

The index k describes the state or the control variable at position k along the horizon. The vector-valued variable x describes the states of the dynamic system. These are $$x=\left[E_{Storage},t,F_{Trac},F_{Brake}\right].$$

In this case, a position-related formulation is chosen, i.e. the position along the horizon is the free variable and the time t becomes a state.

The deviation from the speed specification is defined as follows: $$e_{set}\left(x_k\right)={\left(v_{set,k}-v_k\right)}^2.$$

Here, v _set,k is the set speed and v _k is the actual or recorded speed of the vehicle.

und $${\varphi }_a\left(x_k\right)=w_{a,lin}{\delta }_a\left(x_k\right)+w_{a,quad}{\left({\delta }_a\left(x_k\right)\right)}^2.$$

The other terms of the cost function are defined as follows: $${\varphi }_j\left(x_k\right)=w_{jerk,lin}{\delta }_j\left(x_k\right)+w_{jerk,quad}{\left({\delta }_j\left(x_k\right)\right)}^2$$

and $${\varphi }_a\left(x_k\right)=w_{a,lin}{\delta }_a\left(x_k\right)+w_{a,quad}{\left({\delta }_a\left(x_k\right)\right)}^2.$$

The other terms are used for regularization in the case of a jerk (jerk j) and serve as a convenience function or, in the case of δ _lth , δ _uth , δ _j and δ _a, they represent so-called slip variables in order to penalize the undershooting or exceedance of the lower and upper tolerance limits v _lth and v _uth , which define the speed band specification, or the upper and lower acceleration and jerk limits a ^U , a ^L and j ^U , j ^L . The indices Ith and uth stand for lower threshold and upper threshold.

$$-{\delta }_{uth}\left(x_k\right)+\left(-v_{uth,k}+v_k\right)\le 0$$

$$a\left(x_k\right)-a^U-{\delta }_a\le 0$$

$$-a\left(x_k\right)+a^L-{\delta }_a\le 0$$

$$j\left(x_k\right)-j^U-{\delta }_j\le 0$$

$$-j\left(x_k\right)+j^L-{\delta }_j\le 0$$

The following constraints are defined: $$-{\delta }_{lth}\left(x_k\right)+\left(v_{lth,k}-v_k\right)\le 0$$

$$-{\delta }_{uth}\left(x_k\right)+\left(-v_{uth,k}+v_k\right)\le 0$$

$$a\left(x_k\right)-a^U-{\delta }_a\le 0$$

$$-a\left(x_k\right)+a^L-{\delta }_a\le 0$$

$$j\left(x_k\right)-j^U-{\delta }_j\le 0$$

$$-j\left(x_k\right)+j^L-{\delta }_j\le 0$$

The vector-valued variable u describes the control variables, which consist of the changes in the traction force dF _Trac and the braking force dF _Brake . The acceleration a _MPC , which is passed to the control module, is calculated from these state variables.

The embodiments of the device thus make it possible to use different weights for different driving modes at different speed specifications, which result in different driving behavior.

In this way, the speed specification can be corrected downwards by a value Δv for an energy-efficient driving mode and upwards for a time-oriented driving mode. Based on this adapted speed specification _Vset,adapt, a time weight w _t is now selected so that this adapted set speed is reached. The time weight w _t thus becomes a function of the adapted speed specification and thus w _t (v _set,adapt ).

Likewise, the weight w _set can be chosen to be very small, since the system already follows the speed specification sufficiently through w _E and w _t . w _set can now be used to represent the dynamic deviation from the speed specification according to the requirements.

Furthermore, the embodiments are independent of the type of drive and can be used for motor vehicles with an internal combustion engine as well as with an electric drive and also for a combination of both.

According to a further aspect, a motor vehicle is provided with an embodiment of a previously described device for operating a motor vehicle.

The motor vehicle according to the invention is preferably designed as a motor vehicle, in particular as a passenger car or truck, or as a passenger bus or motorcycle.

With regard to the embodiments of the motor vehicle and the associated advantages, reference is made to the previously described embodiments of the device and the related advantages.

• 1 eine schematische Ansicht einer Ausführungsform einer Vorrichtung zum Betrieb eines Kraftfahrzeugs.

In the following, embodiments of the device for operating a motor vehicle are described in connection with the following figures. Shown here are:

• 1 a schematic view of an embodiment of a device for operating a motor vehicle.

In the figures, identical reference symbols designate functionally identical elements.

1 shows a schematic view of an embodiment of a device 100 for operating a motor vehicle. The device is in particular comprised by a motor vehicle.

The device 100 comprises a model-predictive driving operation module 10, which is designed to generate a driving signal for the motor vehicle in a model-predictive manner as a function of a first driving specification, a second driving specification and a motor vehicle specification, wherein the first driving specification is a speed specification of a driver, wherein the second driving specification is a speed range specification of the driver and wherein the motor vehicle specification is a speed deviation specification.

The device 100 also includes a control module 20 configured to control the motor vehicle based on the generated driving signal.

The model predictive driving operation module 10 of the device 100 is further designed to generate the acceleration signal based on a third driving specification, wherein the third driving specification is a driving mode specification of the driver.

The model predictive driving operation module 10 of the device 100 is also designed to generate the driving signal based on topography information.

The model predictive driving operation module 10 comprises a cost function 11 and is designed to minimize it.

The cost function 11 takes into account the energy available in an energy storage device of the motor vehicle, a deviation from the speed specification and an elapsed time and weights these differently.

reference sign

10

model-predictive driving operation module

11

cost function

20

control module

100

device

Claims (8)

Device (100) for operating a motor vehicle, comprising: - a model-predictive driving operation module (10) which is designed to model-predictively generate a driving signal for the motor vehicle depending on a first driving specification, a second driving specification and a motor vehicle specification, wherein the first driving specification is a speed specification of a driver, wherein the second driving specification is a speed range specification of the driver and wherein the motor vehicle specification is a speed deviation specification; and - a control module (20) which is designed to control the motor vehicle based on the generated driving signal. Device (100) according to claim 1 , where the speed deviation specification depends on the speed specification. Device (100) according to one of the preceding claims, wherein the model predictive driving operation module is further configured to generate the acceleration signal based on a third driving specification, wherein the third driving specification is a driving mode specification of the driver. Device (100) according to one of the preceding claims, wherein the model predictive driving operation module is designed to generate the driving signal based on topography information. Device (100) according to one of the preceding claims, wherein the model predictive driving operation module minimizes a cost function (11). Device (100) according to claim 4 , wherein the cost function (11) takes into account an energy present in an energy storage device of the motor vehicle, a deviation from the speed specification and/or an elapsed time. Device (100) according to claim 5 , wherein the cost function (11) differently weights the energy present in an energy storage device of the motor vehicle, the deviation from the speed setting and/or the elapsed time. Motor vehicle comprising a device (100) according to one of the preceding claims.

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