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

Abstract

Central driver assistance system (1) for at least partially autonomous longitudinal and lateral vehicle control of a vehicle with vehicle sensors (2) and vehicle actuators (3), comprising: - a sensor evaluation unit (4) for fusion and evaluation of sensor data from the vehicle sensor system (2), - a driving process planning unit (5) 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 motion control unit (6) downstream of the driving process planning unit (5) for controlling the vehicle actuators (3) based on the planned trajectory (5a), wherein the vehicle motion 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.

Description

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

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

[0003] Common driver assistance systems for vehicle lateral guidance can be divided into three categories: Driver assistance systems for increasing driving comfort and / or driving safety in a driving scenario with a lateral acceleration of up to a maximum of 3 m / s². 2and sufficient power transmission to all wheels of the vehicle. Examples of these driver assistance systems include lane keeping assist and lane departure warning. Driver assistance systems for vehicle stabilization in highly dynamic driving scenarios with insufficient power transmission to one or more wheels. Examples of these driver assistance systems include electronic stability programs such as ESP or ESC. Driver assistance systems for increasing driving safety through evasive maneuvers, for example, by avoiding an impending collision with a potential collision object. Examples of these driver assistance systems include active evasive steering assist systems such as emergency steering assist.

[0004] These driver assistance systems for lateral vehicle control typically coexist within a single vehicle, each designed for different driving scenarios or tasks. While some systems utilize the same sensor or environmental information and vehicle actuators, others are accessible only to a subset of the driver assistance systems. Furthermore, the coexistence of multiple systems necessitates switching between them during vehicle operation, which regularly involves a change in sensor information sources and available vehicle actuator configurations. For example, in a highly dynamic, critical driving scenario, the system switches from a lane keeping assist system to an electronic stability program, with the target setting changing from an environmental sensor-based trajectory to a steering wheel-based driver input.However, since a driver is typically overwhelmed by the driving task in such a scenario, an environment-sensor-based trajectory would often provide a better target, 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 keeping assist system, so valuable time is lost during the switch to the electronic stability program until the driver's attention is regained and a reliable target can then be set (with a delay). Moreover, the activation of an electronic stability program, for example, is usually based solely on a deviation between a target movement determined from the current steering wheel angle and the actual movement of the vehicle.As a result, appropriate stabilizing interventions are usually performed very late and are severe or uncomfortable.

[0005] German patent DE 10 2016 117 438 A1 describes a vehicle motion control system for a vehicle, wherein the vehicle has several actuators for influencing its motion, such as a steering actuator and a drivetrain. The vehicle motion control system comprises a fusion and localization unit, a behavior planner, a generation unit, and a control unit. The fusion and localization unit is designed to generate a world model based, in particular, on information from the vehicle's environmental sensors, driver input, digital maps, and GPS coordinates. This world model provides, in particular, the course of the vehicle's lane, its current position and orientation, and the positions of obstacles.The behavior planner is trained to determine a driving strategy based on information from the world model, current motion state data from the control device, and a risk assessment. It then determines a corresponding driving function and transmits this to the generation unit. The generation unit is trained to use further information from the world model about the environment to determine a specific driving corridor with an acceleration requirement for the vehicle as target data for the transmitted driving function and provide this information to the control device.The control device is designed to determine guidance data for the target data, in particular a target trajectory along which the control device then guides the vehicle and, if necessary, also intervenes in a stabilizing manner in the wheel and vehicle dynamics, for example by means of an anti-lock braking system and electronic stability package (ABS / ESP), and to output this to an interface to the actuators.

[0006] DE 10 2013 020 558 A1 describes a device for controlling the chassis of a motor vehicle, wherein the vehicle's driving stability is controlled based on a continuously determined environmental model, which is used for predictive adaptation of the vehicle's existing vehicle dynamics control systems or chassis control systems. The device comprises a first module that generates an environmental model based on data from environmental sensors, an antenna for determining the vehicle's current position in maps in a database, and means for detecting other road users and determining the road's course; and a second module for generating a trajectory as a future driving path based on the environmental model.The generated trajectory is then passed as a target value to the existing chassis control systems of the vehicle, which use this as a basis to issue control signals to corresponding actuators of the chassis and adjust accordingly.

[0007] Therefore, there is a need for a central driver assistance system for safe and comfortable, at least partially autonomous longitudinal and lateral vehicle control, which utilizes or can utilize 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 where one or more vehicle wheels do not have sufficient traction.

[0008] It is therefore an object of the invention to provide a driver assistance system for at least partially autonomous longitudinal and lateral vehicle control of a vehicle with vehicle sensors and vehicle actuators, as well as a method for operating such a driver assistance system, which enables safe and reliable and comfortable lateral vehicle control.

[0009] The foregoing problem is solved by the entire teaching of claim 1 and claim 10. Advantageous embodiments and further developments of the invention are set forth in the dependent claims and the following description.

[0010] The central driver assistance system according to the invention for at least partially autonomous longitudinal and lateral vehicle control of a vehicle with vehicle sensors and vehicle actuators comprises: - a sensor evaluation unit for the fusion and evaluation of sensor data from vehicle sensors, - a driving process planning unit 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 motion control unit downstream of the driving process planning unit for controlling the vehicle actuators based on the planned trajectory, wherein the vehicle motion 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.

[0011] A central driver assistance system designed in this way, enabling at least semi-autonomous longitudinal and lateral vehicle control, can utilize all relevant sensors and actuators available in the vehicle. In particular, it allows for continuous and comprehensive monitoring of the vehicle's stability based on all vehicle sensors. This, in turn, enables early, comprehensive, and optimal corrective interventions that can also optimally exploit any existing friction potential. Furthermore, switching between multiple coexisting (sub-)assistance systems is unnecessary, and time losses that would arise, for example, from changing a target reference value are avoided.

[0012] The driver assistance system according to the invention thus has the advantage that it provides a central driver assistance system that enables safe, reliable and comfortable lateral vehicle guidance.

[0013] The central driver assistance system is designed for semi-autonomous or autonomous longitudinal and lateral control 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 control component.

[0014] The sensor evaluation unit receives data or information from the vehicle's sensors, which comprise multiple, in particular all, sensors available in or on the vehicle. It then at least partially fuses the received data or information and evaluates the received data or information and / or the at least partially fused 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's sensors, meaning it can receive data or information from all sensors in the vehicle's sensor system or all sensors available in the vehicle.Preferably, the central driver assistance system also includes a situation interpretation unit located downstream of the sensor evaluation unit and upstream of the driving process planning unit, i.e., between the sensor evaluation unit and the driving process planning unit, for determining or interpreting the current situation in which the vehicle finds itself and / or predicting a future situation in which the vehicle will find itself, based on data or information provided by the sensor evaluation unit. In this case, for example, an environment model generated by the sensor evaluation unit and / or information about other vehicles in the vicinity of the vehicle are provided to the situation interpretation unit.

[0015] The vehicle planning unit advantageously comprises a maneuver planning device for determining a planned vehicle maneuver and a trajectory planning device for calculating a planned trajectory for the planned maneuver. Based on data or information provided by the sensor evaluation unit, or preferably alternatively or additionally based on data or information provided by a situation interpretation unit arranged between the sensor evaluation unit and the vehicle planning unit, the maneuver planning device determines a planned vehicle maneuver, and the trajectory planning device calculates a planned trajectory for the planned 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 then provided to the vehicle motion control unit.

[0016] 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, meaning it can centrally control all actuators of the vehicle actuator system. The vehicle actuator system preferably includes all actuators available in the vehicle relating to active safety, but most preferably all actuators available in the vehicle.

[0017] The vehicle controller module of the vehicle motion control unit is configured to determine the lateral control requirement based on the planned trajectory provided by the driving process planning unit and the current vehicle movement. The lateral control requirement is specifically configured as a curvature requirement or a yaw rate requirement. The vehicle stability detection module is configured, among other things, to determine the current stability state of the vehicle. The determined stability state is specifically defined as "stable," "unstable," "understeering," or "oversteering."Furthermore, the actuator assignment module of the vehicle motion control unit is designed to control the vehicle actuators based on 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, whereby preferably the actual control of the vehicle actuators is limited to the recommended actuator configuration, i.e., actual control of the vehicle actuators only takes place within the framework of the recommended actuator configuration.

[0018] In an advantageous embodiment, the sensor evaluation unit, the driving sequence planning unit, and the vehicle motion control unit are implemented in a central control unit. Thus, the sensor evaluation unit, the driving sequence planning unit, and the vehicle motion control unit are implemented in a common control unit, in particular one designed as an ECU.

[0019] In a further advantageous embodiment, the calculation of the planned trajectory by the driving process planning unit includes the calculation of multidimensional trajectory coordinates along which the vehicle moves when traversing the trajectory, wherein the calculation of the planned trajectory by the driving process planning unit preferably also includes the calculation of speed values ​​and / or acceleration values ​​when traversing the trajectory.

[0020] In a further advantageous embodiment, the vehicle's sensor system comprises an environmental sensor and an inertial sensor, wherein the environmental sensor includes 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 includes an accelerometer and / or a gyroscope. The environmental sensor and the inertial sensor can each also include multiple sensors of the aforementioned sensor type, for example, multiple cameras and / or multiple ultrasonic sensors and / or multiple accelerometers. The communication interface is preferably configured for wirelessly receiving data via a mobile network, a digital broadcast network, a vehicle-to-infrastructure network, and / or a vehicle-to-vehicle network.Preferably, the vehicle sensor system also includes navigation sensors, in particular designed as a navigation system, with a position module, in particular designed as a GPS module, for determining the vehicle's position, as well as a digital map stored in the vehicle, wherein the data or information from the navigation sensors are also provided to the sensor evaluation unit, or the sensor evaluation unit receives data or information from the navigation sensors. The data from the navigation sensors preferably includes the vehicle's current position, the vehicle's position located on the digital map, a currently and / or future traveled route segment on the digital map, and / or traffic information, in particular congestion information, concerning a currently and / or future traveled route segment or the area surrounding the currently and / or future traveled route segment.

[0021] In a further advantageous embodiment, the vehicle actuator comprises a steering system and / or a drive system and / or a braking system, in particular with a brake pressure control function for applying individual wheel pressure to at least two wheel brakes of two vehicle wheels. The vehicle actuator may, in particular, comprise several steering systems. The drive system preferably comprises a drive motor and a transmission of the vehicle, but is especially preferably designed as a drive train of the vehicle, which includes a drive motor, a clutch, a transmission, a drive shaft, and an axle differential.

[0022] In a further advantageous embodiment, the driving process planning unit is also configured to modify the planned trajectory to an adapted trajectory based on the 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 facilitates optimal driving and trajectory planning adapted to the specific situation.

[0023] In a further advantageous embodiment, the vehicle stability detection module is configured 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 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.This allows both the current stability state of the vehicle and the recommended actuator configuration for stabilizing the vehicle to be determined, each based on a planned trajectory calculated by the driving process planning unit and / or current vehicle kinematics and / or current vehicle dynamics and / or wheel speed of a vehicle wheel and / or 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 the wheel speed of a single vehicle wheel and the individual wheel speeds of multiple vehicle wheels, in particular all vehicle wheels, can be used.

[0024] 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 kinematic deviation, which indicates a deviation of a determined actual vehicle kinematics from a determined target vehicle kinematics, with a predetermined kinematic deviation threshold, which is preferably predetermined depending on a current or future vehicle speed and / or a coefficient of friction of the road surface, and a comparison of a determined vehicle dynamic deviation, which indicates a deviation of a determined actual vehicle dynamics from a determined target vehicle dynamics, with a predetermined dynamic deviation threshold.which is preferably predetermined depending on a current or future vehicle speed and / or a coefficient of friction of the road surface, and / or by comparing a determined wheel slip with a predetermined wheel slip threshold value. Preferably, the stability state of the vehicle is determined as an unstable state, in particular as an understeering or oversteering state.if the determined vehicle kinematic deviation is above the specified kinematic deviation threshold, or if the determined vehicle dynamic deviation is above the specified dynamic deviation threshold. Furthermore, preferably, the vehicle kinematic deviation is determined by comparing the actual vehicle kinematics with the target vehicle kinematics, and the vehicle dynamic deviation is determined by comparing the actual vehicle dynamics with the target vehicle dynamics. The comparison of a determined wheel slip with a specified wheel slip threshold is used in particular to determine...whether the power transmission at one or multiple vehicle wheels is exhausted. By comparing a measured wheel slip with a predefined wheel slip threshold, both the measured wheel slip of a single vehicle wheel and the wheel slip of multiple vehicle wheels, particularly all vehicle wheels, can be compared with the wheel slip threshold. Advantageously, the recommended actuator configuration is determined using an optimization or heuristic method.

[0025] In a further advantageous embodiment, the vehicle stability detection module is also configured to determine a corresponding target vehicle kinematics and / or a corresponding target vehicle dynamics for a trajectory coordinate of the planned trajectory, preferably for several trajectory coordinates of the planned trajectory, wherein the corresponding vehicle kinematic deviation is determined by comparing a determined actual vehicle kinematics with the determined corresponding target vehicle kinematics, and / or the corresponding vehicle dynamic deviation is determined by comparing a determined actual vehicle dynamics with the determined corresponding target 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.

[0026] Furthermore, the present invention comprises a method for operating a central driver assistance system according to the invention, wherein the method comprises the following steps: - Fusion and evaluation of sensor data from the vehicle's sensor system by the sensor evaluation unit, - Planning of a driving maneuver and calculation of 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 motion control unit based on the planned trajectory provided by the driving process planning unit and a current vehicle movement, - Determination of the 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 value provided by the vehicle stability detection module

[0027] Stability state and the recommended actuator configuration provided by the vehicle stability detection module for stabilizing the vehicle.

[0028] The advantages and preferred embodiments described for the central driver assistance system according to the invention also apply accordingly to the method according to the invention.

[0029] In a further advantageous embodiment, the planned trajectory is modified to 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.

[0030] 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 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.

[0031] 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 kinematic deviation, which indicates a deviation of a determined actual vehicle kinematics from a determined target vehicle kinematics, with a predetermined kinematic deviation threshold, which is preferably predetermined depending on a current or future vehicle speed and / or a coefficient of friction of the road surface, and a comparison of a determined vehicle dynamic deviation, which indicates a deviation of a determined actual vehicle dynamics from a determined target vehicle dynamics, with a predetermined dynamic deviation threshold, which is preferably predetermined depending on a current or future vehicle speed and / or a coefficient of friction of the road surface.and / or a comparison of a measured wheel slip with a predetermined wheel slip threshold value.

[0032] 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 several trajectory coordinates of the planned trajectory, wherein the corresponding vehicle kinematic deviation is determined by comparing a determined actual vehicle kinematics with the determined corresponding target vehicle kinematics and / or the corresponding vehicle dynamic deviation is determined by comparing a determined actual vehicle dynamics with the determined corresponding target vehicle dynamics.

[0033] Exemplary embodiments of the invention are explained in more detail below with reference to a drawing. The drawing shows: Fig. 1. A driver assistance system in a schematic representation. Fig. 2 in a schematic detailed representation a vehicle motion control unit of the driver assistance system according to Fig. 1, and Fig. 3 schematically a flowchart of a procedure for operating the vehicle stability detection module of the driver assistance system according to Fig. 1.

[0034] In Fig. Figure 1 shows a schematic representation of a driver assistance system 1 for at least partially autonomous longitudinal and lateral vehicle control. The vehicle has vehicle sensors 2 and vehicle actuators 3.

[0035] The vehicle sensor system 2 comprises environmental sensors, inertial sensors, and navigation sensors 2a, thus including several sensors 2b, 2c, ..., 2n, such as one or more cameras, one or more radar sensors, one or more lidar sensors, several ultrasonic sensors, one or more accelerometers, and one or more yaw rate sensors, 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, one drive system with a drive motor, and one braking system.

[0036] 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 fusion and evaluation of sensor data from the vehicle sensors 2, a driving process planning unit 5 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 motion control unit 6 downstream of the driving process planning unit 5 for controlling the vehicle actuators 3 based on the planned trajectory 5a.For example, the driver assistance system 1 also includes a situation interpretation unit (not shown) located downstream of the sensor evaluation unit 4 and upstream of the driving process planning unit 5, i.e., 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.

[0037] The sensor evaluation unit 4 receives data or information from the vehicle sensors 2, for example, from all relevant sensors 2b, 2c, ..., 2n available in or on the vehicle and the navigation sensors 2a. The sensor evaluation unit 4 thus has full access to the vehicle sensors 2. The sensor evaluation unit 4 at least partially fuses the received data or information and evaluates the received data or information and / or the at least partially fused data or information. For example, the sensor evaluation unit 4 generates an environment model and information about other vehicles in the vicinity of the vehicle, which is provided to the situation interpretation unit.

[0038] The vehicle process planning unit 5 comprises a maneuver planning device for determining a planned vehicle maneuver and a trajectory planning device for calculating a planned trajectory 5a for the planned 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 vehicle maneuver, while the trajectory planning device calculates a planned trajectory 5a for the planned maneuver. The vehicle process planning unit 5 is thus configured to calculate a planned trajectory 5a for 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 motion control unit 6.The calculation of the planned trajectory 5a by the driving process planning unit 5 includes, for example, the calculation of multidimensional trajectory coordinates along which the vehicle moves when traversing the trajectory and the calculation of speed values ​​and / or acceleration values ​​when traversing the trajectory 5a.

[0039] The vehicle motion control unit 6 of the driver assistance system 1 according to Fig. 1 is shown in a schematic detailed representation in Fig. 2 shown. The vehicle motion control unit 6 is designed to control the vehicle actuators 3 on the basis of the planned trajectory 5a provided by the driving process planning unit 5.

[0040] 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 the vehicle's current motion 8, which includes, for example, data or information concerning vehicle kinematics and vehicle dynamics; a vehicle stability detection module 9 for determining the vehicle's current stability state 9a 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. The vehicle motion control unit 6, or the actuator assignment module 10, has full access to the vehicle actuators 3 and can therefore centrally control all actuators 3a, 3b, ..., 3n of the vehicle actuators 3.Furthermore, the vehicle motion 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 modify the planned trajectory 5a (continuously) based on the data or information provided in this way to an adapted (planned) trajectory.

[0041] 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 motion 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.Furthermore, 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, whereby 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., actual control of the vehicle actuator 3 only takes place within the framework of the recommended actuator configuration 9b.

[0042] The vehicle stability detection module 9 is further trained to determine the current stability state 9a of the vehicle and the recommended actuator configuration 9b for stabilizing the vehicle based on 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, including data or information concerning the vehicle kinematics and vehicle dynamics, the wheel speeds 11 of the vehicle wheels, and the coefficient of friction 12 of the road surface.

[0043] The vehicle stability detection module 9 is further designed 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 kinematic deviation, which indicates a deviation of a determined actual vehicle kinematics from a determined target vehicle kinematics, with a specified kinematic deviation threshold, a comparison of a determined vehicle dynamic deviation, which indicates a deviation of a determined actual vehicle dynamics from a determined target vehicle dynamics, with a specified dynamic deviation threshold, and a comparison of a determined wheel slip with a specified wheel slip threshold.The kinematic deviation threshold and the dynamic deviation threshold are predetermined, for example, based on a current or future vehicle speed and the coefficient of friction 12 of the road surface. The vehicle's stability state is determined, for example, as unstable, in particular as understeering or oversteering, 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.

[0044] The vehicle stability detection module 9 is also designed to determine, for example, a corresponding target vehicle kinematics and a corresponding target vehicle dynamics for several trajectory coordinates of the planned trajectory 5a. For each of these trajectory coordinates, the corresponding vehicle kinematic deviation is determined by comparing the determined actual vehicle kinematics with the corresponding target vehicle kinematics, and the corresponding vehicle dynamic deviation is determined by comparing the determined actual vehicle dynamics with the corresponding target 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.

[0045] A central driver assistance system 1 designed in this way can 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 based on all vehicle sensors 2, which in turn allows for early, comprehensive, and optimal corrective interventions that can also optimally exploit any existing friction potential. Switching between multiple coexisting (sub-)assistance systems is unnecessary, and time losses that would arise, for example, from changing a target reference value are avoided. Overall, this driver assistance system 1 enables safe, reliable, and comfortable lateral vehicle control.

[0046] Fig. Figure 3 schematically shows a flow diagram of a procedure 100 for operating the vehicle stability detection module 9 of the driver assistance system 1 according to Fig. 1.

[0047] In step 101, a target vehicle kinematics and a target vehicle dynamics are determined for several trajectory coordinates of the planned trajectory 5a.

[0048] In 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.

[0049] In the next step, a vehicle kinematic deviation is determined by comparing the measured actual vehicle kinematics with the measured corresponding target vehicle kinematics, and a vehicle dynamic deviation is determined by comparing the measured actual vehicle dynamics with the measured corresponding target vehicle dynamics. Furthermore, it is determined whether the measured vehicle kinematic and vehicle dynamic deviations exceed a kinematic deviation threshold or a dynamic deviation threshold, respectively. This reveals, for example, that a curvature actually driven by the vehicle is significantly less than a lateral control requirement or curvature requirement determined or requested by the vehicle controller module 7. This suggests an unstable, understeering condition.

[0050] In step 104, the wheel slip is determined for each wheel of the vehicle and compared with a predefined wheel slip threshold value. This determines whether the power transmission at one or more vehicle wheels is exhausted.

[0051] In the next step 105, based on the data or information determined in steps 103 and 104, the vehicle's stability state 9a and the recommended actuator configuration 9b for stabilizing the vehicle are determined. For example, it is determined that the vehicle is in an unstable, understeering state caused by insufficient power transmission to the front axle wheels. The recommended actuator configuration 9b is then modified or specified, for example, to reduce steering intervention at the front axle and to apply the necessary yaw moment to achieve the desired curvature by individually braking the inside rear wheel and / or driving the outside rear wheel.

[0052] In a subsequent step 106, the determined stability state 9a of the vehicle and the determined recommended actuator configuration 9b for stabilizing the vehicle are then transmitted or made available to the driving process planning unit 5 and the actuator assignment module 10, respectively. Based on the data or information thus provided, the driving process planning unit 5 can then, for example, increase a trajectory radius within the framework of a road geometry perceived by the environmental sensors or adjust a speed profile, and the actuator assignment module 10 can also control the vehicle actuator 3 accordingly.

Claims

[1] Central driver assistance system (1) for at least partially autonomous longitudinal and lateral control of a vehicle with vehicle sensors (2) and vehicle actuators (3), comprising: - a sensor evaluation unit (4) for fusion and evaluation of sensor data from the vehicle sensor system (2), - a driving process planning unit (5) 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 motion control unit (6) downstream of the driving process planning unit (5) for controlling the vehicle actuators (3) based on the planned trajectory (5a), wherein the vehicle motion 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] Central driver assistance system (1) according to claim 1, wherein the sensor evaluation unit (4), the driving process planning unit (5) and the vehicle motion control unit (6) are implemented in a central control unit. [3] Central 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) includes the calculation of multidimensional trajectory coordinates along which the vehicle moves when traversing the trajectory, and wherein the calculation of the planned trajectory (5a) by the driving process planning unit (5) preferably also includes the calculation of speed values ​​and / or acceleration values ​​when traversing the trajectory. [4] Central driver assistance system (1) according to one of the preceding claims, wherein the vehicle sensor system (2) of the vehicle comprises an environment sensor system and an inertial sensor system, wherein the environment 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 environment data, and wherein the inertial sensor system comprises an accelerometer and / or a yaw rate sensor. [5] Central driver assistance system (1) according to one of the preceding claims, wherein the vehicle actuator (3) comprises a steering system and / or a drive system and / or a brake system, in particular with a brake pressure control or brake pressure regulation function for applying individual brake pressure to at least two wheel brakes of two vehicle wheels, and wherein the vehicle actuator preferably comprises a steering system and a drive system and a brake system, in particular with a brake pressure control or brake pressure regulation function for applying individual brake pressure to at least two wheel brakes of two vehicle wheels. [6] Central 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 an adapted trajectory. [7] Central driver assistance system (1) according to one of the preceding claims, wherein the vehicle stability detection module (9) is 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 trajectory (5a) calculated by the driving process planning unit (5) and / or current vehicle kinematics and / or current vehicle dynamics and / or wheel speed (11) of a vehicle wheel and / or coefficient of friction (12) of the road surface and / or a lateral guidance requirement (7a) determined by the vehicle controller module (7). [8] Central 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 kinematic deviation, which indicates a deviation of a determined actual vehicle kinematics from a determined target vehicle kinematics, with a predetermined kinematic deviation threshold, 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 a comparison of a determined vehicle dynamic deviation, which indicates a deviation of a determined actual vehicle dynamics from a determined target vehicle dynamics, with a predetermined dynamic deviation threshold.which is preferably predetermined depending on 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 predetermined wheel slip threshold value. [9] Central driver assistance system (1) according to claim 8, wherein the vehicle stability detection module (9) is further configured to determine a corresponding target vehicle kinematics and / or a corresponding target vehicle dynamics for a trajectory coordinate of the planned trajectory (5a), preferably for several trajectory coordinates of the planned trajectory (5a), wherein the corresponding vehicle kinematic deviation is determined by comparing a determined actual vehicle kinematics with the determined corresponding target vehicle kinematics and / or the corresponding vehicle dynamic deviation is determined by comparing a determined actual vehicle dynamics with the determined corresponding target vehicle dynamics. [10] Method (100) for operating a central driver assistance system (1) according to any one of claims 1 to 9, the method comprising the following steps: - Fusion and evaluation of sensor data from the vehicle sensors (2) by the sensor evaluation unit (4), - Planning of a driving maneuver and calculation of 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 motion 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 actuator (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) provided by the vehicle stability detection module (9) to stabilize the vehicle. [11] Method (100) according to claim 10, wherein the planned trajectory (5a) is modified to a modified 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 wheel speed (11) of a vehicle wheel and / or coefficient of friction (12) of the road surface 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 determined based on a comparison of a determined vehicle kinematic deviation, which indicates a deviation of a determined actual vehicle kinematics from a determined target vehicle kinematics, with a predetermined kinematic 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 a comparison of a determined vehicle dynamic deviation, which indicates a deviation of a determined actual vehicle dynamics from a determined target vehicle dynamics, with a predetermined dynamic 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 is determined by comparing a measured wheel slip with a predetermined wheel slip threshold value. [14] Method (100) according to claim 13, wherein for a trajectory coordinate of the planned trajectory (5a), preferably for several trajectory coordinates of the planned trajectory (5a), a corresponding target vehicle kinematics and / or a corresponding target vehicle dynamics is determined, and wherein the corresponding vehicle kinematic deviation is determined by comparing a determined actual vehicle kinematics with the determined corresponding target vehicle kinematics and / or the corresponding vehicle dynamic deviation is determined by comparing a determined actual vehicle dynamics with the determined corresponding target vehicle dynamics.

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