Driver assistance system for longitudinal and lateral guidance of a vehicle and method for operating such a driver assistance system

Abstract

The invention specifies a driver assistance system (1) for at least partially autonomous longitudinal and transverse guidance of a vehicle with a vehicle sensor system (2) and a vehicle actuator system (3), comprising a sensor evaluation unit (4), a driving process planning unit (5) connected downstream of the sensor evaluation unit (4) for calculating a planned trajectory (5a) of the vehicle, and a vehicle movement control unit (6) connected downstream of the driving process planning unit (5) for controlling the vehicle actuator system (3) based on the planned trajectory (5a).The vehicle motion control unit (6) includes a vehicle controller module (7) for determining a lateral guidance request (7a) based on the planned trajectory (5a) and a current vehicle movement, a vehicle stability detection module (9) for determining a current stability state (9a) of the vehicle and a recommended actuator configuration (9b) for stabilizing the vehicle, and an actuator assignment module (10) for controlling the vehicle actuators (3) based on the determined lateral guidance request (7a), the current stability state (9a), and the recommended actuator configuration (9b) for stabilizing the vehicle. The invention further provides a method (100) for operating such a driver assistance system (1).

Description

[0001] The invention relates to a driver assistance system for at least partially autonomous longitudinal and lateral guidance of a vehicle, comprising vehicle sensors and vehicle actuators. The invention further relates to methods for operating such a driver assistance system.

[0002] Today, vehicles with a partially or fully automated driving system are already known, which partially or fully assume control or guidance of the vehicle as part of a semi-autonomous or autonomous operation or driving of the vehicle. Such an automated driving system has, for example, a steering system that controls the (wheel) steering angle of the vehicle. Driver assistance systems are commonly known that can initiate or execute various driving maneuvers based on a current driving scenario and calculate a trajectory along which the vehicle moves partially or fully automatically, i.e., for example, without steering intervention by the driver and / or without the driver operating the accelerator or brake pedal.

[0003] Common driver assistance systems for lateral vehicle guidance can be divided into three categories: Driver assistance systems to increase driving comfort and / or driving safety in a driving scenario with a lateral acceleration of up to 3 m / s 2and sufficient power transmission to all wheels of the vehicle. These driver assistance systems can include, for example, a lane keeping assistant and a lane departure prevention system. Driver assistance systems for vehicle stabilization in a highly dynamic driving scenario with insufficient power transmission to one or more vehicle wheels. These driver assistance systems can include, for example, electronic stability programs such as ESP or ESC. Driver assistance systems for increasing driving safety by evasive maneuvers, for example by avoiding an impending collision with a potential collision object. These driver assistance systems can include, for example, active evasive assistants such as an emergency steering assistant.

[0004] Typically, these driver assistance systems for lateral vehicle guidance coexist in a vehicle, with each driver assistance system being developed for a different driving scenario or task. While some of the same sensor or environmental information and vehicle actuators are used for this purpose, there are also sensor or environmental information and vehicle actuators that are only accessible to some of the driver assistance systems. Furthermore, the coexistence of multiple driver assistance systems creates the need to switch between them during vehicle operation, which regularly involves a change in the sensor information sources and available vehicle actuator configuration. For example, in a highly dynamic, critical driving scenario, a switch from a lane keeping assistant to an electronic stability program occurs, with a target specification changing from an environmental sensor-based trajectory to a steering wheel-based driver input.However, since a driver is usually overwhelmed by the driving task in such a driving scenario, the environment sensor-based trajectory would in many cases provide a better target specification, which can also take into account information such as obstacles, oncoming traffic, direction of travel, etc. Furthermore, the driver may not be fully focused while using the lane departure warning system, so valuable time is lost while switching to the electronic stability program until the driver's attention is regained, so that a reliable target specification can then be provided (with a delay). Furthermore, the triggering of an electronic stability program, for example, is usually based exclusively on a deviation between a target movement determined from a current steering wheel angle and the actual movement of the vehicle.As a result, corresponding stabilizing interventions are usually carried out very late and are severe or uncomfortable.

[0005] There is therefore a need for a central driver assistance system for safe and at the same time comfortable, at least partially autonomous vehicle longitudinal and lateral guidance, which uses or can use all available relevant sensor or environmental information and relevant vehicle actuators equally and which is particularly active in driving scenarios with low and high dynamics as well as in driving scenarios in which one or more vehicle wheels do not have sufficient road grip.

[0006] It is therefore an object of the invention to provide a driver assistance system for at least partially autonomous longitudinal and lateral guidance of a vehicle with a vehicle sensor system and a vehicle actuator system as well as a method for operating such a driver assistance system, which enables safe and reliable and at the same time comfortable lateral guidance of the vehicle.

[0007] The above object is achieved by the entire teaching of claim 1 and claim 14. Expedient embodiments and further developments of the invention are set out in the subclaims and the following description.

[0008] The driver assistance system according to the invention for at least partially autonomous longitudinal and transverse guidance of a vehicle with vehicle sensors and vehicle actuators comprises: - a sensor evaluation unit for merging and evaluating sensor data from the vehicle sensors, - a driving process planning unit connected downstream of the sensor evaluation unit for planning a driving maneuver and calculating a planned trajectory of the vehicle for the planned driving maneuver based on the fused and evaluated sensor data, and - a vehicle movement control unit connected downstream of the driving process planning unit for controlling the vehicle actuators based on the planned trajectory, wherein the vehicle movement control unit has - a vehicle controller module for determining a lateral guidance requirement based on the planned trajectory and a current vehicle movement, - a vehicle stability detection module for determining the current stability state of the vehicle and a recommended actuator configuration for stabilizing the vehicle, and - an actuator assignment module for controlling the vehicle actuators based on the determined lateral guidance requirement, the current stability state and the recommended actuator configuration for stabilizing the vehicle.

[0009] A central driver assistance system designed in this way for at least partially autonomous longitudinal and lateral vehicle guidance allows this single driver assistance system to utilize all relevant sensors and actuators available in the vehicle. In particular, it enables continuous and comprehensive monitoring of the vehicle's stability state based on the entire vehicle sensor system, which in turn enables early, comprehensive, and optimal corrective interventions that can also optimally utilize existing friction coefficient potential. Furthermore, switching between multiple coexisting (sub-)assistance systems is not required, and time losses that would otherwise arise, for example, from changing a target reference value, are avoided.

[0010] The driver assistance system according to the invention thus has the advantage of providing a driver assistance system that enables safe, reliable and comfortable lateral vehicle guidance.

[0011] The driver assistance system is designed for semi-autonomous or autonomous longitudinal and lateral guidance of the vehicle, i.e. for taking over or carrying out partial or complete control or guidance of the vehicle with a longitudinal and lateral guidance component.

[0012] The sensor evaluation unit receives data or information from the vehicle sensor system, which includes several sensors, in particular all sensors available in or on the vehicle, and at least partially merges the received data or information and evaluates the received data or information and / or the at least partially merged data or information. For example, the sensor evaluation unit generates an environment model that is provided to the driving process planning unit. Advantageously, the sensor evaluation unit has full access to the vehicle sensor system, i.e., it can receive data or information from all sensors of the vehicle sensor system or all sensors available in the vehicle.Preferably, the driver assistance system also comprises a situation interpretation unit downstream of the sensor evaluation unit and upstream of the driving process planning unit, i.e., arranged between the sensor evaluation unit and the driving process planning unit, for determining or interpreting the current situation in which the vehicle is located and / or predicting a future situation in which the vehicle will be located in the future, based on data or information provided by the sensor evaluation unit. In this case, for example, an environmental model generated by the sensor evaluation unit and / or information on other vehicles in the area surrounding the vehicle are provided to the situation interpretation unit.

[0013] The driving process planning unit advantageously comprises a maneuver planning device for determining a planned driving maneuver of the vehicle and a trajectory planning device for calculating a planned trajectory of the planned driving maneuver. Based on the data or information provided by the sensor evaluation unit, preferably alternatively or additionally based on data or information provided by a situation interpretation unit arranged between the sensor evaluation unit and the driving process planning unit, the maneuver planning device determines a planned driving maneuver of the vehicle, with the trajectory planning device calculating a planned trajectory for the planned driving maneuver.The driving process planning unit is thus ultimately designed to calculate a planned trajectory of the vehicle based on data or information provided by the sensor evaluation unit, which is provided to the vehicle movement control unit.

[0014] The vehicle motion control unit comprises the vehicle controller module, the vehicle stability detection module, and the actuator assignment module and is configured to control the vehicle actuators based on the planned trajectory provided by the driving process planning unit. Advantageously, the vehicle motion control unit or the actuator assignment module has full access to the vehicle actuators, thus being able to centrally control all actuators of the vehicle actuators. The vehicle actuators preferably comprise all actuators related to active safety available in the vehicle, but particularly preferably all actuators available in the vehicle.

[0015] The vehicle controller module of the vehicle motion control unit is configured to determine the lateral guidance requirement based on the planned trajectory provided by the driving process planning unit and a current vehicle movement. The lateral guidance requirement is configured, in particular, as a curvature requirement or a yaw rate requirement. The vehicle stability detection module is configured, among other things, to determine a current stability state of the vehicle. The determined stability state is determined, in particular, as "stable," "unstable," "understeering," or "oversteering."In addition, the actuator assignment module of the vehicle motion control unit is designed to control the vehicle actuators of the vehicle on the basis of the determined lateral guidance requirement, the current stability state and the recommended actuator configuration for stabilizing the vehicle, i.e. to generate corresponding output or control signals for the vehicle actuators, wherein the actual control of the vehicle actuators is preferably limited to the recommended actuator configuration, i.e. an actual control of the vehicle actuators only takes place within the framework of the recommended actuator configuration.

[0016] In an advantageous embodiment, the sensor evaluation unit, the driving process planning unit, and the vehicle movement control unit are implemented in a central control unit. The sensor evaluation unit, the driving process planning unit, and the vehicle movement control unit are thus implemented in a common control unit, particularly in the form of an ECU.

[0017] In a further advantageous embodiment, the calculation of the planned trajectory by the driving process planning unit comprises the calculation of multidimensional trajectory coordinates along which the vehicle moves when traveling through the trajectory, wherein the calculation of the planned trajectory by the driving process planning unit preferably also comprises the calculation of speed values ​​and / or acceleration values ​​when traveling through the trajectory.

[0018] In a further advantageous embodiment, the vehicle sensor system of the vehicle comprises an environmental sensor system and an inertial sensor system, wherein the environmental sensor system comprises a camera and / or a radar sensor and / or a lidar sensor and / or an ultrasonic sensor and / or a communication interface for wirelessly receiving data, in particular current environmental data, and wherein the inertial sensor system has an acceleration sensor and / or a yaw rate sensor. The environmental sensor system and the inertial sensor system can each also have a plurality of sensors of a specified sensor type, for example a plurality of cameras and / or a plurality of ultrasonic sensors and / or a plurality of acceleration sensors. The communication interface is preferably designed for wirelessly receiving data via a mobile radio network, a digital broadcasting network, a vehicle-to-infrastructure network and / or a vehicle-to-vehicle network.The vehicle sensor system preferably also comprises a navigation sensor system, in particular designed as a navigation system, with a position module, in particular designed as a GPS module, for determining a position of the vehicle and a digital map stored in the vehicle, wherein the data or information from the navigation sensor system is also provided to the sensor evaluation unit or the sensor evaluation unit receives data or information from the navigation sensor system. The data from the navigation sensor system preferably includes a current position of the vehicle, a localization of the position of the vehicle in the digital map, a currently and / or future route section traveled on in the digital map and / or traffic information, in particular traffic jam information, relating to a currently and / or future route section traveled on or an environment of the currently and / or future route section traveled on.

[0019] In a further advantageous embodiment, the vehicle actuator system comprises a steering system and / or a drive system and / or a braking system, in particular with a brake pressure regulation or brake pressure control function for exerting a wheel-specific braking pressure on at least two wheel brakes of two vehicle wheels. The vehicle actuator system can in particular comprise multiple steering systems. The drive system preferably comprises a drive motor and a transmission of the vehicle, but is particularly preferably designed as a drive train of the vehicle, which has a drive motor, a clutch, a transmission, a drive shaft, and an axle differential.

[0020] In a further advantageous embodiment, the driving process planning unit is further configured to modify the planned trajectory into an adapted trajectory based on a current stability state of the vehicle determined by the vehicle stability detection module and a recommended actuator configuration determined by the vehicle stability detection module. This further promotes the most optimal driving or trajectory planning possible, adapted to the specific situation.

[0021] In a further advantageous embodiment, the vehicle stability detection module is designed to determine the current stability state of the vehicle and / or the recommended actuator configuration for stabilizing the vehicle based on a trajectory calculated by the driving process planning unit and / or current vehicle kinematics and / or current vehicle dynamics and / or a wheel speed of a vehicle wheel and / or a coefficient of friction of the road surface and / or a lateral guidance requirement determined by the vehicle controller module.Both the current stability state of the vehicle and the recommended actuator configuration for stabilizing the vehicle can be determined based on a planned trajectory calculated by the driving process planning unit and / or current vehicle kinematics and / or current vehicle dynamics and / or a wheel speed of a vehicle wheel and / or a coefficient of friction of the road surface and / or a lateral guidance requirement determined by the vehicle controller module.Alternatively, either only the current stability state of the vehicle or only the recommended actuator configuration for stabilizing the vehicle can be determined based on a planned trajectory calculated by the driving process planning unit and / or current vehicle kinematics and / or current vehicle dynamics and / or a wheel speed of a vehicle wheel and / or a coefficient of friction of the road surface and / or a lateral guidance requirement determined by the vehicle controller module. When using a wheel speed of a vehicle wheel, both a wheel speed of only one (single) vehicle wheel and a (respective) wheel speed of multiple vehicle wheels, in particular of all vehicle wheels, can be used.

[0022] In a further advantageous embodiment, the vehicle stability detection module is further configured to determine the current stability state of the vehicle and / or the recommended actuator configuration for stabilizing the vehicle based on a comparison of a determined vehicle kinematics deviation, which indicates a deviation of a determined actual vehicle kinematics from a determined target vehicle kinematics, with a predetermined kinematics deviation threshold value, which is preferably predetermined as a function of a current or future vehicle speed and / or a coefficient of friction of the road surface, a comparison of a determined vehicle dynamics deviation, which indicates a deviation of a determined actual vehicle dynamics from a determined target vehicle dynamics, with a predetermined dynamics deviation threshold value,which is preferably predetermined as a function of a current or future vehicle speed and / or a coefficient of friction of the road surface, and / or a comparison of a determined wheel slip with a predetermined wheel slip threshold value. Preferably, the stability state of the vehicle is determined as an unstable, in particular as an understeering or oversteering, state.if the determined vehicle kinematics deviation is above the specified kinematics deviation threshold value or if the determined vehicle dynamics deviation is above the specified dynamics deviation threshold value. Furthermore, the vehicle kinematics deviation is preferably determined by comparing a determined actual vehicle kinematics with a determined target vehicle kinematics, and the vehicle dynamics deviation is preferably determined by comparing a determined actual vehicle dynamics with a determined target vehicle dynamics. The comparison of a determined wheel slip with a specified wheel slip threshold value serves in particular to determine,Whether the power transmission at one or more vehicle wheels is exhausted. When comparing a determined wheel slip with a specified wheel slip threshold, both the determined wheel slip of only one vehicle wheel can be compared with the wheel slip threshold, as well as the (respective) wheel slip of several vehicle wheels, in particular of all vehicle wheels, with the wheel slip threshold. Advantageously, the recommended actuator configuration is determined using an optimization method or a heuristic method.

[0023] In a further advantageous embodiment, the vehicle stability detection module is further configured to determine a corresponding desired vehicle kinematics and / or a corresponding desired vehicle dynamics for a trajectory coordinate of the planned trajectory, preferably for a plurality of trajectory coordinates of the planned trajectory, wherein the corresponding vehicle kinematics deviation is determined by comparing a determined actual vehicle kinematics with the determined corresponding desired vehicle kinematics and / or the corresponding vehicle dynamics deviation is determined by comparing a determined actual vehicle dynamics with the determined corresponding desired vehicle dynamics. Preferably, the actual vehicle kinematics and / or the actual vehicle dynamics can be determined for a current point in time and predicted for one or more future points in time.

[0024] Furthermore, the present invention comprises a method for operating a driver assistance system according to the invention, the method comprising the following steps: - Fusion and evaluation of sensor data from the vehicle sensors by the sensor evaluation unit, - Planning a driving maneuver and calculating a planned trajectory of the vehicle for the planned driving maneuver by the driving process planning unit based on the fused and evaluated sensor data provided by the sensor evaluation unit, and - Determination of a lateral guidance request by the vehicle controller module of the vehicle movement control unit based on the planned trajectory provided by the driving process planning unit and a current vehicle movement, - Determination of a current stability state of the vehicle and a recommended actuator configuration for stabilizing the vehicle by the vehicle stability detection module of the vehicle motion control unit, and - Control of the vehicle actuators by the actuator assignment module of the vehicle motion control unit based on the determined lateral guidance requirement provided by the vehicle controller module, the current stability state provided by the vehicle stability detection module and the recommended actuator configuration for stabilizing the vehicle provided by the vehicle stability detection module.

[0025] The advantages and preferred embodiments described for the driver assistance system according to the invention also apply accordingly to the method according to the invention.

[0026] In a further advantageous embodiment, the planned trajectory is modified into an adapted trajectory based on a current stability state of the vehicle determined by the vehicle stability detection module and a recommended actuator configuration determined by the vehicle stability detection module.

[0027] In a further advantageous embodiment, the current stability state of the vehicle and / or the recommended actuator configuration for stabilizing the vehicle is determined based on a planned trajectory calculated by the driving process planning unit and / or current vehicle kinematics and / or current vehicle dynamics and / or a wheel speed of a vehicle wheel and / or a coefficient of friction of the road surface and / or a lateral guidance requirement determined by the vehicle controller module.

[0028] In a further advantageous embodiment, the current stability state of the vehicle and / or the recommended actuator configuration for stabilizing the vehicle is determined based on a comparison of a determined vehicle kinematics deviation, which indicates a deviation of a determined actual vehicle kinematics from a determined target vehicle kinematics, with a predetermined kinematics deviation threshold value, which is preferably predetermined as a function of a current or future vehicle speed and / or a coefficient of friction of the road surface, a comparison of a determined vehicle dynamics deviation, which indicates a deviation of a determined actual vehicle dynamics from a determined target vehicle dynamics, with a predetermined dynamics deviation threshold value, which is preferably predetermined as a function of a current or future vehicle speed and / or a coefficient of friction of the road surface,and / or a comparison of a determined wheel slip with a specified wheel slip threshold value.

[0029] In a further advantageous embodiment, a corresponding target vehicle kinematics and / or a corresponding target vehicle dynamics are determined for a trajectory coordinate of the planned trajectory, preferably for a plurality of trajectory coordinates of the planned trajectory, wherein the corresponding vehicle kinematics deviation is determined by comparing a determined actual vehicle kinematics with the determined corresponding target vehicle kinematics and / or the corresponding vehicle dynamics deviation is determined by comparing a determined actual vehicle dynamics with the determined corresponding target vehicle dynamics.

[0030] Embodiments of the invention are explained in more detail below with reference to a drawing. In the drawings: Fig. 1 shows a schematic representation of a driver assistance system, Fig. 2 shows a schematic detailed representation of a vehicle movement control unit of the driver assistance system according to Fig. 1, and Fig. 3 schematically shows a flow diagram of a method for operating the vehicle stability detection module of the driver assistance system according to Fig. 1.

[0031] In Fig. Figure 1 shows a schematic representation of a driver assistance system 1 for at least partially autonomous longitudinal and lateral guidance of a vehicle. The vehicle has a vehicle sensor system 2 and a vehicle actuator system 3.

[0032] The vehicle sensor system 2 comprises an environmental sensor system, an inertial sensor system and a navigation sensor system 2a, i.e. a total of several sensors 2b, 2c, ..., 2n, such as, for example, one (several) camera(s), one (several) radar sensor(s), one (several) lidar sensor(s), several ultrasonic sensors, one (several) acceleration sensor(s) and one (several) yaw rate sensor(s), as well as, for example, a GPS module and a digital map of the navigation sensor system 2a. The vehicle actuator system 3 comprises several actuators 3a, 3b, ..., 3n, such as, for example, at least one steering system, a drive system with a drive motor and a braking system.

[0033] The driver assistance system 1 is designed as a (single) central driver assistance system 1 implemented in a central control unit and comprises a sensor evaluation unit 4 for merging and evaluating sensor data from the vehicle sensor system 2, a driving process planning unit 5 connected downstream of the sensor evaluation unit 4 for planning a driving maneuver and calculating a planned trajectory 5a of the vehicle for the planned driving maneuver based on the fused and evaluated sensor data, and a vehicle movement control unit 6 connected downstream of the driving process planning unit 5 for controlling the vehicle actuator system 3 based on the planned trajectory 5a.By way of example, the driver assistance system 1 also comprises a situation interpretation unit (not shown) arranged downstream of the sensor evaluation unit 4 and upstream of the driving process planning unit 5, i.e. arranged between the sensor evaluation unit 4 and the driving process planning unit 5, for determining or interpreting the current situation in which the vehicle is located and / or predicting a future situation in which the vehicle will be located in the future, based on data or information provided by the sensor evaluation unit 4.

[0034] The sensor evaluation unit 4 receives data or information from the vehicle sensor system 2, for example, from all relevant sensors 2b, 2c, ..., 2n available in or on the vehicle and from the navigation sensor system 2a. The sensor evaluation unit 4 therefore has full access to the vehicle sensor system 2. The sensor evaluation unit 4 at least partially merges the received data or information and evaluates the received data or information and / or the at least partially merged data or information. For example, the sensor evaluation unit 4 generates an environment model and information on other vehicles in the area surrounding the vehicle, which is provided to the situation interpretation unit.

[0035] The driving process planning unit 5 comprises a maneuver planning device for determining a planned driving maneuver of the vehicle and a trajectory planning device for calculating a planned trajectory 5a of the planned driving maneuver. Based on the data or information provided by the sensor evaluation unit 4 or the situation interpretation unit, the maneuver planning device determines a planned driving maneuver of the vehicle, with the trajectory planning device calculating a planned trajectory 5a for the planned driving maneuver. The driving process planning unit 5 is thus configured to calculate a planned trajectory 5a of the vehicle based on data or information provided by the sensor evaluation unit 4 or the situation interpretation unit, which is then provided to the vehicle movement control unit 6.The calculation of the planned trajectory 5a by the driving process planning unit 5 includes, for example, the calculation of multi-dimensional trajectory coordinates along which the vehicle moves when traveling through the trajectory and the calculation of speed values ​​and / or acceleration values ​​when traveling through the trajectory 5a.

[0036] The vehicle movement control unit 6 of the driver assistance system 1 according to Fig. 1 is a schematic detailed representation in Fig. 2. The vehicle motion control unit 6 is configured to control the vehicle actuator system 3 based on the planned trajectory 5a provided by the driving process planning unit 5.

[0037] For this purpose, the vehicle motion control unit 6 comprises a vehicle controller module 7 for determining a lateral guidance requirement 7a based on the calculated planned trajectory 5a and a current vehicle movement 8 of the vehicle, which, for example, comprises data or information relating to vehicle kinematics and vehicle dynamics, a vehicle stability detection module 9 for determining a current stability state 9a of the vehicle and a recommended actuator configuration 9b for stabilizing the vehicle, and an actuator assignment module 10 for controlling the vehicle actuator system 3 based on the determined lateral guidance requirement 7a, the current stability state 9a and the recommended actuator configuration 9b. The vehicle motion control unit 6 or the actuator assignment module 10 has complete access to the vehicle actuator system 3 and can therefore centrally control all actuators 3a, 3b, ..., 3n of the vehicle actuator system 3.In addition, the vehicle movement control unit 6 is designed to provide the current stability state 9a determined by the vehicle stability detection module 9 and the determined recommended actuator configuration 9b to the driving process planning unit 5, which is designed to (continuously) modify the planned trajectory 5a based on the data or information thus provided to an adapted (planned) trajectory.

[0038] The vehicle controller module 7 of the vehicle motion control unit 6 is thus configured to determine the lateral guidance requirement 7a based on the planned trajectory 5a provided by the driving process planning unit 5 and a current vehicle movement 8, wherein the lateral guidance requirement 7a is configured, for example, as a curvature requirement or a yaw rate requirement. The vehicle stability detection module 9 is configured to determine a current stability state 9a of the vehicle, wherein the determined stability state 9a can be determined in particular as "stable," "unstable," "understeering," or "oversteering," and to determine a recommended actuator configuration 9b for stabilizing the vehicle.In addition, the actuator assignment module 10 is designed to control the vehicle actuator 3 of the vehicle on the basis of the determined lateral guidance requirement 7a, the current stability state 9a and the recommended actuator configuration 9b, i.e. to generate corresponding output or control signals for the vehicle actuator 3, wherein the actual control of the vehicle actuator 3 is limited to the recommended actuator configuration 9b determined by the vehicle stability detection module 9, i.e. an actual control of the vehicle actuator 3 only takes place within the framework of the recommended actuator configuration 9b.

[0039] The vehicle stability detection module 9 is further configured to determine the current stability state 9a of the vehicle and the recommended actuator configuration 9b for stabilizing the vehicle on the basis of the lateral guidance requirement 7a determined by the vehicle controller module 7, the planned trajectory 5a calculated by the driving process planning unit 5, the current vehicle movement 8, comprising data or information relating to the vehicle kinematics and vehicle dynamics, detected wheel speeds 11 of the vehicle wheels of the vehicle and a friction coefficient 12 of the road surface.

[0040] The vehicle stability detection module 9 is further configured to determine the current stability state 9a of the vehicle and the recommended actuator configuration 9b for stabilizing the vehicle based on a comparison of a determined vehicle kinematics deviation, which indicates a deviation of a determined actual vehicle kinematics from a determined target vehicle kinematics, with a predetermined kinematics deviation threshold value, a comparison of a determined vehicle dynamics deviation, which indicates a deviation of a determined actual vehicle dynamics from a determined target vehicle dynamics, with a predetermined dynamics deviation threshold value, and a comparison of a determined wheel slip with a predetermined wheel slip threshold value.The kinematic deviation threshold and the dynamic deviation threshold are predetermined, for example, based on a current or future vehicle speed and the friction coefficient 12 of the road surface. The stability state of the vehicle is determined, for example, as an unstable state, in particular as an understeering or oversteering state, if the determined vehicle kinematic deviation is above the predetermined kinematic deviation threshold and / or if the determined vehicle dynamic deviation is above the predetermined dynamic deviation threshold.

[0041] The vehicle stability detection module 9 is also configured, for example, to determine a corresponding desired vehicle kinematics and a corresponding desired vehicle dynamics for a plurality of trajectory coordinates of the planned trajectory 5a, wherein for the plurality of trajectory coordinates, the corresponding vehicle kinematics deviation is determined by comparing the determined actual vehicle kinematics with the determined corresponding desired vehicle kinematics, and the corresponding vehicle dynamics deviation is determined by comparing the determined actual vehicle dynamics with the determined corresponding desired vehicle dynamics. The actual vehicle kinematics and / or the actual vehicle dynamics can be determined for a current point in time and predicted for one or more future points in time.

[0042] A central driver assistance system 1 configured in this way can, in principle, utilize all sensors 2a, 2b, ..., 2n and actuators 3a, 3b, ..., 3n available in the vehicle. In particular, it enables continuous and comprehensive monitoring of the vehicle's stability state based on the entire vehicle sensor system 2, which in turn enables early, comprehensive, and optimal corrective interventions that can also optimally utilize existing friction coefficient potential. No switching between multiple coexisting (sub-)assistance systems is required, and time losses that would arise, for example, from changing a target reference value are avoided. This type of driver assistance system 1 thus enables safe, reliable, and comfortable lateral vehicle guidance.

[0043] Fig. 3 schematically shows a flow chart of a method 100 for operating the vehicle stability detection module 9 of the driver assistance system 1 according to Fig. 1.

[0044] In a step 101, a target vehicle kinematics and a target vehicle dynamics are first determined for several trajectory coordinates of the planned trajectory 5a.

[0045] In a step 102, a corresponding actual vehicle kinematics and a corresponding actual vehicle dynamics are determined for the current time step and predicted for future time steps.

[0046] In a next step 103, a vehicle kinematics deviation is determined by comparing the determined actual vehicle kinematics with the determined corresponding target vehicle kinematics, and a vehicle dynamics deviation is determined by comparing the determined actual vehicle dynamics with the determined corresponding target vehicle dynamics. Furthermore, it is determined whether the respectively determined vehicle kinematics deviations and vehicle dynamics deviations are above a kinematics deviation threshold value or a dynamics deviation threshold value. This determines, for example, that a curvature actually traveled by the vehicle is significantly lower than a lateral guidance requirement or curvature requirement 7a determined or required by the vehicle controller module 7. This allows conclusions to be drawn about an unstable, understeering condition.

[0047] In step 104, wheel slip is determined for each wheel of the vehicle, and the determined wheel slips are compared with a predefined wheel slip threshold value. This determines whether the power transmission to one or more vehicle wheels is exhausted.

[0048] In a next step 105, the stability state 9a of the vehicle and the recommended actuator configuration 9b for stabilizing the vehicle are then determined based on the data or information determined in steps 103 and 104. For example, it is determined that the vehicle is in an unstable, understeering state, caused by insufficient power transmission to the vehicle wheels on the front axle. The recommended actuator configuration 9b is consequently changed or specified, for example, such that steering intervention on the front axle of the vehicle is reduced and a necessary yaw moment is applied to achieve a desired curvature by individually braking the inside rear wheel of the vehicle and / or driving the outside rear wheel of the vehicle.

[0049] In a next step 106, the determined stability state 9a of the vehicle and the determined recommended actuator configuration 9b for stabilizing the vehicle are then forwarded or provided to the driving process planning unit 5 and the actuator assignment module 10, respectively. Based on the data or information thus provided, a trajectory radius can then be increased, for example, within the context of a road geometry perceived by the environmental sensors, or a speed profile can be adjusted in the driving process planning unit 5, and the actuator assignment module 10 can also control the vehicle actuator system 3 accordingly.

Claims

[1] Driver assistance system (1) for at least partially autonomous longitudinal and transverse guidance of a vehicle with a vehicle sensor system (2) and a vehicle actuator system (3), comprising: - a sensor evaluation unit (4) for merging and evaluating sensor data from the vehicle sensor system (2), - a driving process planning unit (5) connected downstream of the sensor evaluation unit (4) for planning a driving maneuver and calculating a planned trajectory (5a) of the vehicle for the planned driving maneuver based on the fused and evaluated sensor data, and - a vehicle movement control unit (6) connected downstream of the driving process planning unit (5) for controlling the vehicle actuators (3) based on the planned trajectory (5a), wherein the vehicle movement control unit (6) has - a vehicle controller module (7) for determining a lateral guidance request (7a) based on the planned trajectory (5a) and a current vehicle movement, - a vehicle stability detection module (9) for determining a current stability state (9a) of the vehicle and a recommended actuator configuration (9b) for stabilizing the vehicle, and - an actuator assignment module (10) for controlling the vehicle actuators (3) based on the determined lateral guidance requirement (7a), the current stability state (9a) and the recommended actuator configuration (9b) for stabilizing the vehicle. [2] Driver assistance system (1) according to claim 1, wherein the sensor evaluation unit (4), the driving process planning unit (5) and the vehicle movement control unit (6) are implemented in a central control unit. [3] Driver assistance system (1) according to claim 1 or 2, wherein the calculation of the planned trajectory (5a) by the driving process planning unit (5) comprises the calculation of multi-dimensional trajectory coordinates along which the vehicle moves when traveling through the trajectory, and wherein the calculation of the planned trajectory (5a) by the driving process planning unit (5) preferably also comprises the calculation of speed values ​​and / or acceleration values ​​when traveling through the trajectory. [4] Driver assistance system (1) according to one of the preceding claims, wherein the vehicle sensor system (2) of the vehicle comprises an environmental sensor system and an inertial sensor system, wherein the environmental sensor system comprises a camera and / or a radar sensor and / or a lidar sensor and / or an ultrasonic sensor and / or a communication interface for wirelessly receiving data, in particular current environmental data, and wherein the inertial sensor system has an acceleration sensor and / or a yaw rate sensor. [5] Driver assistance system (1) according to one of the preceding claims, wherein the vehicle actuator system (3) comprises a steering system and / or a drive system and / or a braking system, in particular with a brake pressure regulation or brake pressure control function for exerting a wheel-specific braking pressure on at least two wheel brakes of two vehicle wheels, and wherein the vehicle actuator system preferably comprises a steering system and a drive system and a braking system, in particular with a brake pressure regulation or brake pressure control function for exerting a wheel-specific braking pressure on at least two wheel brakes of two vehicle wheels. [6] Driver assistance system (1) according to one of the preceding claims, wherein the driving process planning unit (5) is further configured to modify the planned trajectory (5a) based on a current stability state (9a) of the vehicle determined by the vehicle stability detection module (9) and a recommended actuator configuration (9b) determined by the vehicle stability detection module (9) to form an adapted trajectory. [7] Driver assistance system (1) according to one of the preceding claims, wherein the vehicle stability detection module (9) is designed to determine the current stability state (9a) of the vehicle and / or the recommended actuator configuration (9b) for stabilizing the vehicle based on a trajectory (5a) calculated by the driving process planning unit (5) and / or current vehicle kinematics and / or current vehicle dynamics and / or a wheel speed (11) of a vehicle wheel and / or a coefficient of friction (12) of the roadway and / or a lateral guidance requirement (7a) determined by the vehicle controller module (7). [8] Driver assistance system (1) according to claim 7, wherein the vehicle stability detection module (9) is further configured to determine the current stability state (9a) of the vehicle and / or the recommended actuator configuration (9b) for stabilizing the vehicle based on a comparison of a determined vehicle kinematics deviation, which indicates a deviation of a determined actual vehicle kinematics from a determined target vehicle kinematics, with a predetermined kinematics deviation threshold value, which is preferably predetermined as a function of a current or future vehicle speed and / or a coefficient of friction (12) of the roadway, a comparison of a determined vehicle dynamics deviation, which indicates a deviation of a determined actual vehicle dynamics from a determined target vehicle dynamics, with a predetermined dynamics deviation threshold value,which is preferably predetermined as a function of a current or future vehicle speed and / or a coefficient of friction (12) of the roadway, and / or a comparison of a determined wheel slip with a predetermined wheel slip threshold value. [9] Driver assistance system (1) according to claim 8, wherein the vehicle stability detection module (9) is further configured to determine a corresponding desired vehicle kinematics and / or a corresponding desired vehicle dynamics for a trajectory coordinate of the planned trajectory (5a), preferably for a plurality of trajectory coordinates of the planned trajectory (5a), wherein the corresponding vehicle kinematics deviation is determined by comparing a determined actual vehicle kinematics with the determined corresponding desired vehicle kinematics and / or the corresponding vehicle dynamics deviation is determined by comparing a determined actual vehicle dynamics with the determined corresponding desired vehicle dynamics. [10] Method (100) for operating a driver assistance system (1) according to one of claims 1 to 9, wherein the method comprises the following steps: - Fusion and evaluation of sensor data from the vehicle sensors (2) by the sensor evaluation unit (4), - Planning a driving maneuver and calculating a planned trajectory (5a) of the vehicle for the planned driving maneuver by the driving process planning unit (5) based on the fused and evaluated sensor data provided by the sensor evaluation unit (4), and - Determination of a lateral guidance request (7a) by the vehicle controller module (7) of the vehicle movement control unit (6) based on the planned trajectory (5a) provided by the driving process planning unit (5) and a current vehicle movement, - Determination of a current stability state (9a) of the vehicle and a recommended actuator configuration (9b) for stabilizing the vehicle by the vehicle stability detection module (9) of the vehicle motion control unit (6), and - Control of the vehicle actuators (3) by the actuator assignment module (10) of the vehicle motion control unit (6) based on the determined lateral guidance requirement (7a) provided by the vehicle controller module (7), the current stability state (9a) provided by the vehicle stability detection module (9) and the recommended actuator configuration (9b) for stabilizing the vehicle provided by the vehicle stability detection module (9). [11] Method (100) according to claim 10, wherein the planned trajectory (5a) is modified to an adapted trajectory based on a current stability state (9a) of the vehicle determined by the vehicle stability detection module (9) and a recommended actuator configuration (9b) determined by the vehicle stability detection module (9). [12] Method (100) according to claim 10 or 11, wherein the current stability state (9a) of the vehicle and / or the recommended actuator configuration (9b) for stabilizing the vehicle is determined based on a planned trajectory (5a) calculated by the driving process planning unit (5) and / or current vehicle kinematics and / or current vehicle dynamics and / or a wheel speed (11) of a vehicle wheel and / or a coefficient of friction (12) of the roadway and / or a lateral guidance requirement (7a) determined by the vehicle controller module (7). [13] Method (100) according to claim 12, wherein the current stability state (9a) of the vehicle and / or the recommended actuator configuration (9b) for stabilizing the vehicle is based on a comparison of a determined vehicle kinematics deviation, which indicates a deviation of a determined actual vehicle kinematics from a determined target vehicle kinematics, with a predetermined kinematics deviation threshold value, which is preferably predetermined as a function of a current or future vehicle speed and / or a coefficient of friction (12) of the road surface, a comparison of a determined vehicle dynamics deviation, which indicates a deviation of a determined actual vehicle dynamics from a determined target vehicle dynamics, with a predetermined dynamics deviation threshold value, which is preferably predetermined as a function of a current or future vehicle speed and / or a coefficient of friction (12) of the road surface,and / or a comparison of a determined wheel slip with a specified wheel slip threshold value. [14] Method (100) according to claim 13, wherein for a trajectory coordinate of the planned trajectory (5a), preferably for a plurality of trajectory coordinates of the planned trajectory (5a) in each case, a corresponding desired vehicle kinematics and / or a corresponding desired vehicle dynamics is determined, and wherein the corresponding vehicle kinematics deviation is determined by comparing a determined actual vehicle kinematics with the determined corresponding desired vehicle kinematics and / or the corresponding vehicle dynamics deviation is determined by comparing a determined actual vehicle dynamics with the determined corresponding desired vehicle dynamics.

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