Control device and method for controlling the operation of a motor vehicle

Abstract

The invention relates to a control device for controlling the operation of a motor vehicle, said control device being designed to determine a target trajectory for a turning action of the motor vehicle, to determine a course of a turning radius and / or a turning curvature of the target trajectory on the basis of the target trajectory, and controlling a steering device of the motor vehicle on the basis of the determined change process of the turning radius and / or the turning curvature. The control of the steering device may include optionally continuously controlling a steering gear ratio of the steering device and / or setting a fixed value for the steering gear ratio based on an average value of the turning radius and / or the turning curvature.

Description

Technical Field

[0001] The present disclosure relates to a control device or control unit for controlling the operation of a motor vehicle, a motor vehicle having the control device, and / or a (control) method for controlling the operation of a motor vehicle. Additionally or alternatively, a computer program is provided, which includes commands that, when the program is executed by a computer, cause the computer to at least partially execute the method. Additionally or alternatively, a computer-readable medium is provided, which includes commands that, when the commands are executed by a computer, cause the computer to at least partially execute the method. Background Art

[0002] In modern motor vehicles, especially cars, an increasing number of driving assistance systems are installed.

[0003] A driving assistance system (FAS; (Advanced) Driving Assistance System, (A)DAS) is an electronic device, especially a mechatronic device, in a motor vehicle for supporting the driver in specific driving situations. Here, safety aspects are usually important, but an improvement in driving comfort is also important.

[0004] There are driving assistance systems here that are designed to automatically control the longitudinal guidance and lateral guidance of a motor vehicle. This can additionally include assisting in turning in intersection situations in urban spaces, where, based on a so-called steer-by-wire system, there is a higher potential for adjustment possibilities for the driving assistance system compared to a conventional steering device with mechanical force transmission.

[0005] However, in the above-mentioned conventional driving assistance systems, it may additionally occur that the driver needs to change the grip during an automatic turn or assisted turn (where the steering wheel of the motor vehicle moves automatically). Summary of the Invention

[0006] Based on the background of the prior art, the task of the present disclosure is to provide an improved device and / or an improved method, which are respectively suitable for enriching the prior art.

[0007] This task is solved by the features of the independent claims. The side-by-side claims and the dependent claims respectively contain optional improvements of the present disclosure.

[0008] Thereby, this task is solved by a control device for controlling the operation of a motor vehicle, wherein the control device is designed to determine the course of change of the turning radius and / or the turning curvature, and to control the steering device of the motor vehicle based on the determined course of change of the turning radius and / or the turning curvature. The control of the steering device includes continuously controlling the steering ratio of the steering device and / or setting a fixed value for the steering ratio based on the turning radius and / or the turning curvature, optionally according to the average value of the turning radius and / or the turning curvature.

[0009] The control device or control unit can be part of a driver assistance system or represent the driver assistance system. The control device can be, for example, an electronic control unit (ECU). The electronic control unit can be an intelligent unit controlled by a processor, which can communicate with other modules via, for example, a central gateway (CGW) and, if necessary, form a vehicle network with a communication control device and / or an environmental sensor system via a field bus, such as a CAN bus, LIN bus, MOST bus, FlexRay, and / or via automotive Ethernet.

[0010] It is conceivable that the control device controls functions related to the driving behavior of the motor vehicle, such as steering, engine control, power transmission, and / or braking systems. In addition, driver assistance systems, such as parking assistants, adaptive cruise control, lane keeping assistants, lane change assistants, traffic sign recognition, light signal recognition, start assistants, night vision assistants, and / or intersection assistants, can be controlled by the control device.

[0011] The term turning radius or radius of a curve can be understood as the radius traversed when the motor vehicle passes through a curve along a target trajectory. According to some embodiments, the term turning radius can also be understood as the radius of a curve, road, or lane shown, for example, in a digital map or according to an environmental model (e.g., additionally based on optical detection by means of a camera). A similar situation applies to the term curvature of a turn.

[0012] During a turning maneuver, the course of change of the turning radius refers to the change in its size or its absolute value, optionally also the change in the absolute value. A similar situation applies to the term curvature of a turn.

[0013] A turning maneuver can be a turning action and / or a drive around an especially sharp curve, such as a drive at a hairpin bend in a slalom.

[0014] As long as the term "control" is used herein, it should be understood as control and / or regulation.

[0015] During a turning maneuver, according to some embodiments, the (automatic) control of the steering device can be carried out to support the manual lateral guidance of the motor vehicle. In other embodiments, the automatic control of the steering device can be achieved without manual intervention.

[0016] The above-mentioned control device has many advantages here. In addition, what the control device allows is to set the steering wheel angle in the case of longitudinal and lateral guidance turning situations, taking into account the turning radius and / or the curvature of the turn in the turning situation, as will be described in further detail later.

[0017] Subsequently, possible improvements to the above-mentioned control device will be elaborated in detail.

[0018] The control device can be designed to determine the target trajectory of a motor vehicle during a turning maneuver and to determine the course of change of the turning radius and / or the turning curvature based on the target trajectory.

[0019] As long as the terms "target" and "actual" are used herein, the target value refers to a desired or to-be-achieved value. In contrast, the actual value is the value that actually exists in reality.

[0020] The term trajectory can be understood as a path along which the motor vehicle moves or should move. In addition to location or position information, the trajectory can also include a time component, i.e., when the motor vehicle should be where.

[0021] The control device can be designed to determine the target trajectory based on the current position of the motor vehicle and map data.

[0022] According to some embodiments, it can be provided that the target trajectory is determined based on the course of change of the turning radius and / or the turning curvature.

[0023] The map data can include the center line of the turning lane and / or the trajectory of at least one motor vehicle that has performed a turning maneuver, and the control device can be designed to determine the target trajectory based on the center line of the lane and / or the trajectory.

[0024] The control device can be designed to determine the target trajectory based on the longitudinal and lane guidance, which has been determined based on the sensor data of the environment sensor system of the motor vehicle.

[0025] The control device can be designed to take into account, when generating a control signal, the yaw rate, the longitudinal acceleration, and / or the lateral acceleration of the motor vehicle that has been determined based on the sensor data of at least one driving dynamics sensor of the motor vehicle.

[0026] The control of the steering device can be carried out such that the steering wheel angle of the steering wheel of the steering device of the motor vehicle does not exceed a predetermined maximum steering wheel angle.

[0027] The above can be rephrased and summarized as described subsequently in possible more specific design options of the present disclosure, where the following description should not be construed as a limitation of the present disclosure.

[0028] Generally, a driving situation can be assumed in which a (motor) vehicle is longitudinally and laterally guided into an intersection with the assistance of an ADAS system and performs a turning maneuver to the left or right. By precisely positioning the vehicle's lane when entering the intersection and using map information, such as the measured lane centerline of a turning lane, the target trajectory of the turning maneuver is determined. The map information can also be determined, for example, by a statistical evaluation of the trajectories traveled by a vehicle fleet during a turning maneuver. The target trajectory can additionally be derived from the lane guidance determined by the vehicle's environmental sensor system (such as radar, lidar, a camera system with image processing, etc.).

[0029] The course of the turning radius and / or the turning curvature of the trajectory of the turning maneuver can be determined from the target trajectory thus obtained. In addition to considering the yaw rate, the longitudinal and lateral accelerations from the driving dynamics sensors, via the course of the turning radius and / or the turning curvature of the target trajectory, a defined course of the rotational movement of the vehicle's steering wheel can be achieved by adjusting the steering ratio. Therefore, the steering wheel movement can additionally be adjusted according to the turning radius and / or the turning curvature to be achieved.

[0030] The steering ratio can be continuously adjusted according to the course of the turning radius and / or the turning curvature here, or set to a fixed set value, for example, according to the minimum or maximum turning radius and / or the turning curvature occurring during the turning maneuver.

[0031] The steering ratio between the steering wheel angle and the achieved steering angle can be controlled, optionally adjusted, by different methods / systems, for example, by adapting the steering ratio on the front axle steering device with the aid of a superimposed transmission (so-called "active front axle steering"), by adapting the steering ratio by setting the steering angle on the active rear axle steering device and / or by adapting the steering ratio of a steer-by-wire system on the front axle and / or the rear axle.

[0032] In particular, a driving situation can be assumed in which a vehicle is longitudinally and laterally guided into an intersection with the assistance of an ADAS system and performs a right turning maneuver with a minimum turning radius of, for example, 10 m. The target trajectory and the target speed profile of the turning maneuver can be determined based on the precise positioning of the vehicle's lane in the intersection entry situation and based on the measured lane centerline. In addition to implementing an adjustment steering torque for lateral adjustment based on the signals of the driving dynamics sensors regarding the yaw rate, longitudinal and lateral accelerations, and a regulation logic or model for mapping the vehicle dynamics, a target course of the steering ratio can also be determined in order to achieve a defined course of the steering wheel angle that does not require a change in the grip on the steering wheel during the turning maneuver. With a steer-by-wire system, the steering torque to be achieved can be set with the corresponding steering ratio.

[0033] Furthermore, a motor vehicle having the above-described control unit is provided.

[0034] The motor vehicle can be a passenger car, in particular an automobile, or a commercial vehicle, such as a truck.

[0035] The motor vehicle can be automated. The motor vehicle can be designed to at least partially and / or at least temporarily assume longitudinal guidance and / or lateral guidance by means of a control device during the automated driving of the motor vehicle.

[0036] The automated driving can be carried out such that the forward movement of the motor vehicle is (to a large extent) autonomous. The automated driving can be controlled at least partially and / or temporarily by means of a control device.

[0037] It is conceivable that the motor vehicle actively intervenes in the lateral guidance of the motor vehicle, for example, by adapting the actual steering wheel position, and optionally passively, for example, by indicating a turn signal, by means of a driving assistance system.

[0038] The above description of the control device similarly applies to the motor vehicle, and vice versa.

[0039] Furthermore, a method for controlling the operation of a motor vehicle is described, wherein the method includes determining the course of change of the turning radius and / or the turning curvature, and controlling the steering device of the motor vehicle based on the determined course of change of the turning radius and / or the turning curvature. The control of the steering device includes continuously controlling the steering ratio of the steering device and / or setting a fixed value for the steering ratio based on the turning radius and / or the turning curvature, optionally according to the average value of the turning radius and / or the turning curvature.

[0040] The control method can be a computer-implemented method, that is, one, several, or all steps of the method can be at least partially executed by a computer or a device for data processing (optionally the control device).

[0041] The above description of the control device and the motor vehicle similarly also applies to the control method, and vice versa.

[0042] Furthermore, a computer program is provided, which includes commands that, when the program is executed by a computer, cause the computer to at least partially implement or execute the above-described method. The program code of the computer program can exist in any code, in particular in a code suitable for the control of a motor vehicle.

[0043] The above description of the control device, the motor vehicle, and the method similarly also applies to the computer program, and vice versa.

[0044] Furthermore, a computer-readable medium, in particular a computer-readable storage medium, is provided. The computer-readable medium includes instructions which, when executed by a computer, cause the computer to at least partially implement the above-described method.

[0045] That is to say, a computer-readable medium including the computer program defined above can be provided. The computer-readable medium can be any digital data storage device, such as a USB stick, a hard disk, a CD-ROM, an SD card or an SSD card.

[0046] The computer program does not necessarily have to be stored on such a computer-readable storage medium to be provided to the motor vehicle, but can also be obtained externally via the Internet or in other ways.

[0047] The above descriptions of the method, the control device, the computer program and the motor vehicle similarly also apply to the computer-readable medium, and vice versa. Description of the Drawings

[0048] Subsequently, reference is made to Figure 1 and Figure 2 to describe the embodiments.

[0049] Figure 1 A motor vehicle having a control device according to the present disclosure in an exemplary driving situation is schematically shown in a bird's-eye view, and

[0050] Figure 2 is schematically shown Figure 1 a flowchart of a method for controlling the operation of a motor vehicle according to the present disclosure implemented by the control device in the driving situation shown. Detailed Embodiments

[0051] In Figure 1 only schematically shown, the motor vehicle 1 has a steering wheel 5, a front axle steering device 6, a rear axle steering device 7, wherein the above three parts of the steering device or steering system of the motor vehicle 1 are a control device 8 connected to the front axle steering device 6, the rear axle steering device 7 and the steering wheel 5. The steering system or steering device of the motor vehicle 1 is currently a so-called steer-by-wire system. Steer-by-wire is understood as a system in vehicle technology, in which steering commands are forwarded from the steering wheel 5 via one or more control devices only electrically (but optionally in a mechanical backup mode) to the corresponding electromechanical actuators of the front axle steering device 6 and the rear axle steering device 7 that execute the steering commands. In such a system, there is no mechanical connection between the steering wheel 5 of the motor vehicle 1 and the steering wheels.

[0052] Figure 1 The motor vehicle 1 shown approaches an intersection 9, at which the motor vehicle turns right or left under the control of the control device 8. To control the turning process, the control device executes subsequent reference is also made to Figure 2Method (control) described in detail.

[0053] In the first step S1 of the method, the control device 8 determines or obtains a target trajectory 21 for a turning maneuver, where the turning maneuver is currently a turning action of the motor vehicle 1. The control device 8 currently determines the target trajectory 21 based on the current position of the motor vehicle 1 and map data, in which the center line 2 of a turning lane 22 is stored. It is noted here that additionally or alternatively, when determining the target trajectory 21, a trajectory stored in the map data can be used, which is based on the recorded trajectories of multiple motor vehicles that have performed turning maneuvers from a motor vehicle fleet. Additionally or alternatively, i.e., alternatively, it is also conceivable in the absence of map data that the control device 8 determines the target trajectory 21 based on lane guidance, which has been determined based on the sensor data of an (not shown) environmental sensor system of the motor vehicle 1.

[0054] In the second step S2 of the method, the control device 8 determines or obtains the variation process of the turning radius 10 of the target trajectory 21 based on the target trajectory 21. According to the target trajectory 21 obtained in the first step S1 (where here, different trajectories are possible, as shown by the additional possible target trajectories 3 or 4 in Figure 1 ), the turning radius 10 can vary along the turning maneuver. For example, in the Figure 1 shown example, this occurs when the motor vehicle 1 turns left. When turning left, during the turning maneuver, the turning radius 10 increases, i.e., the curvature of the target trajectory 21 decreases.

[0055] In the third step S3 of the method, the control device 8 controls the front axle steering device 6 and the rear axle steering device 7 based on the obtained variation process of the turning radius 10, more precisely the actuators provided accordingly, and thus at least controls the lateral guidance of the motor vehicle 1 such that the motor vehicle 1 follows the target trajectory 21 as precisely as possible during the turning maneuver. It is also conceivable that the control device performs the turning maneuver completely automatically, i.e., in addition to the lateral guidance, it also controls the longitudinal guidance of the motor vehicle 1 during the turning maneuver. Here, the control device 8 takes into account the yaw rate, longitudinal acceleration, and / or lateral acceleration of the motor vehicle 1, which have been determined based on the sensor data of at least one (not shown) driving dynamics sensor of the motor vehicle 1. The control of the steering device can also be carried out in different combinable ways.

[0056] For example, the steering ratio of the continuously controlled steering device and / or the fixed value set for the steering ratio can optionally be carried out by the control device 8 as a function of the average value of the turning radius 10. However, the control of the steering device can also be carried out additionally or alternatively such that the steering angle of the steering wheel 5 of the steering device of the motor vehicle 1 does not exceed a predetermined maximum steering wheel angle, i.e., such that the driver does not have to cross their hands during a turning maneuver.

[0057] List of reference signs

[0058] 1 Motor vehicle

[0059] 2 Lane center

[0060] 21 Target trajectory

[0061] 22 Turning lane

[0062] 3 Change in the target trajectory during a right turning maneuver

[0063] 4 Change in the target trajectory during a left turning maneuver

[0064] 5 Steering wheel

[0065] 6 Front axle steering device

[0066] 7 Rear axle steering device

[0067] 8 Control device

[0068] 9 Intersection

[0069] 10 Turning radius

[0070] S1 - S3 Method steps

Claims

1. A control device (8) for controlling the operation of a motor vehicle (1), wherein, the control device (8) is designed to: - determine the course of change of the turning radius and / or the turning curvature (10), and - control the steering device (5-7) of the motor vehicle (1) based on the determined course of change of the turning radius and / or the turning curvature (10), characterized in that - the control of the steering device (5-7) includes: continuously controlling the steering ratio of the steering device (5-7) and / or setting a fixed value for the steering ratio based on the turning radius and / or the turning curvature (10).

2. The control device (8) according to claim 1, characterized in that the control device (8) is designed to determine the target trajectory (21) of the motor vehicle (1) during a turning maneuver and to determine the course of change of the turning radius and / or the turning curvature (10) based on the target trajectory (21).

3. The control device (8) according to claim 2, characterized in that the control device (8) is designed to determine the target trajectory (21) based on the current position of the motor vehicle (1) and map data.

4. The control device (8) according to claim 3, characterized in that the map data includes the center line (2) of a turning lane (22) and / or the trajectory of at least one motor vehicle that has performed the turning maneuver, and the control device (8) is designed to determine the target trajectory (21) based on the center line (2) or the trajectory.

5. The control device (8) according to any one of claims 1 to 4, characterized in that the control device (8) is designed to determine the target trajectory (21) based on lane guidance, which has been determined based on sensor data of the environment sensor system of the motor vehicle (1).

6. The control device (8) according to any one of claims 1 to 5, characterized in that the control device (8) is designed to take into account the yaw rate, longitudinal acceleration, and / or lateral acceleration of the motor vehicle (1) determined based on sensor data of at least one driving dynamics sensor of the motor vehicle (1) when generating the control signal.

7. The control device (8) according to any one of claims 1 to 6, characterized in that the control of the steering device (5-7) is carried out such that the steering wheel angle of the steering wheel (5) of the steering device (5-7) of the motor vehicle (1) does not exceed a predetermined maximum steering wheel angle.

8. A motor vehicle (1), characterized in that the motor vehicle (1) includes the control device (8) according to any one of claims 1 to 7.

9. A method for controlling the operation of a motor vehicle (1), wherein, the method includes: - determining (S2) the course of change of the turning radius and / or the turning curvature (10), and - controlling (S3) the steering device (5-7) of the motor vehicle (1) based on the determined course of change of the turning radius and / or the turning curvature (10), Characterized in that the control (S3) of the steering device (5-7) comprises: - Based on the turning radius and / or the turning curvature (10), continuously controlling the steering gear ratio of the steering device (5-7) and / or setting a fixed value for the steering gear ratio.

10. A computer program and / or a computer-readable medium, Characterized in that, The computer program or the computer-readable medium includes instructions that, when executed by a computer, cause the computer to perform the method according to claim 9.

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