Method for operating a vehicle system, motor vehicle and computer program

Abstract

The invention relates to a method for operating a vehicle system (2), which provides an autonomous driving function for fully automatically guiding a motor vehicle (1), which autonomous driving function can be used within a system boundary described by at least one system boundary parameter to be obeyed for an environmental parameter describing an environmental condition, in order to determine and execute an autonomous vehicle guidance measure, in particular a driving maneuver, of an autonomous driving function within a base guidance range described by at least one base guidance boundary parameter, in the event that at least one relevant current environmental parameter violates at least one system boundary parameter, the autonomous vehicle guidance measure is determined and executed. At least one adjustment condition that evaluates the current environmental parameter is checked, and if the adjustment condition is satisfied, the autonomous vehicle guidance function is provided with a reduced guidance range described by a guidance boundary parameter that depends on the satisfied adjustment condition and / or the current environmental parameter.

Description

Technical Field

[0001] This invention relates to a method for operating a vehicle system that provides an autonomous driving function for fully automated guidance of a motor vehicle. This autonomous driving function is operable within a system boundary / system limit described by at least one system boundary parameter / system constraint parameter to be followed for environmental parameters describing environmental conditions. This enables the determination and execution of autonomous vehicle guidance measures, particularly driving maneuvers, within a basic guidance range described by at least one basic guidance boundary parameter. Furthermore, the present invention relates to a motor vehicle and a computer program. Background Technology

[0002] Vehicle systems that allow fully automated guidance of motor vehicles within certain limitations, or so-called system boundaries, are already available and are a subject of research, particularly on roads where fully autonomous motor vehicles can operate. According to the SAE J3016 standard of April 30, 2021, autonomous driving is divided into five levels, with fully automated guidance achieved from Level 3 onwards. At Level 3, the vehicle system performs all aspects of the dynamic driving task in a driving mode-specific manner, provided that the driver is expected to respond to intervention requests (driver takeover invitations). This expectation no longer exists at higher levels.

[0003] Autonomous driving functions are typically designed to operate within certain system boundaries, within which the vehicle guidance measures of the autonomous driving function are safe. The vehicle guidance measures involved here are those permissible by the autonomous driving function that can be determined within the basic guidance range described by guidance boundary parameters. System boundaries can be defined at least in part by system boundary parameters relating to environmental conditions. Therefore, for example, in foggy weather, especially in low visibility conditions, and / or in poor road conditions (e.g., slippery or wet), autonomous driving systems on highways may not be usable. This requires the driver, who cannot use the autonomous driving function and especially needs to assume the task of vehicle guidance, to take responsibility. Summary of the Invention

[0004] The purpose of this invention is to improve the usability of autonomous driving under environmental conditions.

[0005] To achieve this objective, in the method described at the beginning, particularly in a computer-implemented manner, according to the invention, if at least one relevant current environmental parameter violates at least one system boundary parameter, at least one adjustment condition for evaluating the current environmental parameter is checked, and if the adjustment condition is met, an autonomous vehicle guidance function is provided with a narrowed guidance range described by a guidance boundary parameter that depends on the satisfied adjustment condition and / or the current environmental parameter.

[0006] Here, according to the SAE J3016 standard of April 30, 2021, autonomous driving function is specifically at least a Level 3 driving function, which means that the vehicle system takes over vehicle guidance and thus completely takes over dynamic driving tasks within the scope of autonomous driving function.

[0007] This proposal suggests that, outside the system boundaries, and at least under certain adjustment conditions, autonomous driving functionality will still be provided within a narrowed, i.e., limited, scope. Here, "provided" should be understood as meaning that if the autonomous driving function has already been activated, it will remain activated, thus avoiding the need to request driver intervention. "Provided" also includes providing the possibility of activating the autonomous driving function even when it has not yet been activated.

[0008] Here, limitations are adapted based on environmental conditions outside the system boundary, as described by the current environmental parameters. This means that if the system boundary is not violated—that is, depending on the type of boundary parameters—and if the current environmental parameters are not higher, lower, or equal to the relevant system boundary parameters, autonomous driving functionality can still be provided within the full range defined by the basic guidance range. Therefore, there is no need to design and reduce the functionality of the autonomous driving function itself to ensure its continued usability. Instead, limitations can be targeted only when environmental conditions exceed the system boundary. These limitations can be compensated for by a reduced guidance range compared to the basic guidance range, thus still allowing safe use of autonomous driving functionality, albeit within a smaller area.

[0009] Here, the adjusted, narrowed guidance range can be allocated based on the adjustment conditions that are met, or it can be derived from the current environmental parameters that violate the system boundaries.

[0010] In this way, by adjusting system behavior for new system boundaries, higher availability of autonomous driving capabilities is achieved. Therefore, autonomous driving can be provided even under harsh environmental conditions.

[0011] Specifically, the current environmental parameters can be defined as relating to weather conditions and / or road conditions. For example, environmental parameters related to fog or other visibility limitations could be the current visibility, particularly the current visibility of at least one sensor used during autonomous driving. Furthermore, weather conditions and / or road conditions, i.e., environmental parameters, can also relate to slipperiness due to wetness or icing. Different road surface types can also be described by environmental parameters, since, for example, some autonomous driving functions cannot be used on unpaved roads; here, system boundary parameters can describe the permitted road surface types. System boundary parameters and / or environmental parameters can also specifically relate to environmental detection characteristics, particularly the quality of available sensor data. Therefore, for example, situations where sensors are covered by ice, snow, or dirt can be considered.

[0012] A specific design of this invention may specify that at least one guidance boundary parameter, adjusted restrictively within a guidance range reduced compared to the basic guidance range, excludes at least one driving maneuver, particularly overtaking and / or lane changing. This means, in particular, that safety-critical driving maneuvers, such as lane changing and overtaking, can be eliminated. Therefore, for example, poor visibility conditions can be taken into account.

[0013] However, it is also appropriate to include at least one guidance boundary parameter that is restrictively adjusted within a guidance range that is smaller than the basic guidance range, particularly describing the reduced maximum permissible dynamic parameters, especially the maximum speed and / or maximum angular velocity and / or maximum longitudinal acceleration and / or maximum lateral acceleration and / or time distance to the vehicle ahead, depending on the driving maneuver. In this way, especially when restrictions are specifically imposed according to driving maneuver, certain driving maneuvers can also be provided in a restricted manner, such as allowing lane changes to the right and / or allowing overtaking maneuvers only when there is a large speed difference. For example, cornering can be done more slowly, i.e., at a lower maximum speed, and / or lateral acceleration can be reduced compared to the basic guidance range. However, the restricted guidance boundary parameter can also involve all conceivable vehicle guidance measures, such as a general reduction in the maximum permissible speed. Dynamic parameters can also be related to other traffic participants, thus constituting relative dynamic parameters. An example of this is the time distance related to, for example, the vehicle being followed when following. Using a larger time distance achieves safer following. In this way, for example, poor road conditions, especially slippery conditions, can be taken into account.

[0014] In a suitable improvement, it can be stipulated that, as autonomous driving functionality is provided with a reduced guidance range, a notification message is output to at least one occupant of the vehicle, particularly the driver. This means informing the driver that the autonomous driving function is currently only available to a limited extent and therefore may not meet their expectations, such as regarding speed. If more detailed information is to be provided to the occupant, the notification message could describe the restrictions on the guidance range, such as providing information on the current maximum permissible speed and / or canceled or limitedly permitted driving maneuvers. This allows the driver to decide whether they want to accept these restrictions and hand over driving to the vehicle system, even if it may result in a slower arrival, or whether they want to take back control of the vehicle's guidance themselves, especially by disabling the autonomous driving function. Similarly, when the autonomous driving function is not activated, the driver can decide to what extent they still wish to use it under restricted conditions.

[0015] In an improved embodiment of the invention, multiple adjustment conditions may be specified, these adjustment conditions being tailored to different environmental parameters and / or with different assigned reduced guidance ranges. Therefore—and also additionally or alternatively, by specifically using the current environmental parameters to determine the reduced guidance range—the limitations can be specifically adapted to the actual environmental conditions. In particular, limiting only to the extent practically necessary in this way increases driver acceptance of the motor vehicle and always provides it with suitable performance.

[0016] In this regard, a particularly suitable improvement specifies the use of at least one set of adjustment conditions for different sub-intervals of the values ​​of current environmental parameters that violate system boundary parameters, wherein each of these adjustment conditions is assigned a narrowing guide range describing progressive restrictions. For example, different visibility ranges checked by different adjustment conditions can be used to progressively restrict driving maneuvers and / or cancel driving maneuvers and / or reduce the maximum permissible dynamic parameters. It should be noted here that the adjustment conditions, and sets of adjustment conditions, can involve multiple environmental parameters.

[0017] Various solutions have been proposed in the prior art to determine current environmental parameters, and these solutions can also be used within the scope of this invention. Therefore, for example, it can be specified that the current environmental parameters are determined by sensor data from at least one sensor of the vehicle and / or from the vehicle's operating data and / or from the vehicle's communication devices. For example, an assessment of radar data from a radar sensor can provide a warning of limited visibility due to rainfall, an assessment of camera data can provide a warning of fog, and typically an assessment of road-related sensor data can provide a warning of road conditions. The presence of skidding can be inferred, for example, from the vehicle's operating data, and the communication data may also include, for example, current weather data, which includes warnings about weather conditions.

[0018] In addition to the method, the present invention also relates to a motor vehicle having a vehicle system with a control device that provides autonomous driving functionality for fully automated guidance of the motor vehicle, wherein the control device is designed to execute the method according to the invention. All embodiments related to the method according to the invention can be similarly adapted to the motor vehicle according to the invention; therefore, the advantages already described can also be obtained by the motor vehicle according to the invention.

[0019] The control device may include at least one processor and at least one storage device. The functional units for performing the steps of the method according to the invention may be formed by hardware and / or software. Therefore, the control device may include, for example, a system boundary monitoring unit for monitoring whether system boundaries are met, a checking unit for checking whether at least one adjustment condition is met, and an adjustment unit for adjusting the guidance range of the autonomous driving function if the adjustment condition is met. Of course, other functional units known in principle may also be provided, such as a planning unit for determining vehicle guidance measures and a control unit for correspondingly manipulating components of the motor vehicle.

[0020] The computer program according to the invention can be directly loaded into the storage device of the control device of a motor vehicle system, and includes program means that cause the control device to perform the steps of the method according to the invention when the computer program is run on the control device. The computer program can be stored on an electronically readable data carrier, especially a non-transitory data carrier. Attached Figure Description

[0021] Other advantages and details of the invention are given by the embodiments described below and with reference to the accompanying drawings. Wherein:

[0022] Figure 1 A flowchart illustrating an embodiment of the method according to the present invention is shown, and...

[0023] Figure 2 A schematic diagram of a motor vehicle according to the present invention is shown. Detailed Implementation

[0024] Figure 1 A flowchart of an embodiment of the method according to the invention is shown. Here (regardless of whether the autonomous driving function for fully automated guidance of the motor vehicle provided by the vehicle system is activated), in step S1, the environmental conditions around the motor vehicle, described by the current environmental parameters, are continuously checked by the control device of the vehicle system to see if they are within the system boundaries of the autonomous function.

[0025] Here, the system boundary is described at least in part by system boundary parameters, which can be thresholds or data representing permissible conditions. Current environmental parameters are compared with the system boundary parameters. These current environmental parameters and the system boundary may relate to, for example, weather conditions and / or road conditions. The current environmental parameters can be determined by sensors, based on operational data, and / or based on communication data from vehicle communication devices.

[0026] If the change in environmental conditions is within the system boundary, return to step S1 in the next time step and update the environmental parameters. However, if at least one system boundary parameter is violated, proceed to step S2.

[0027] In step S2, it is checked whether adjustment conditions are met. These adjustment conditions evaluate at least one current environmental parameter that violates the corresponding system boundary parameter. Specifically, there are multiple adjustment conditions, which may at least partially involve different current environmental parameters or different sets of current environmental parameters. A set of adjustment conditions is provided for at least one environmental parameter, which examines different sub-intervals of the parameter's value. These sub-intervals correspond to different, progressively deeper restrictions on the guidance range, as will be described in more detail below. Ideally, the parts to be satisfied by the different adjustment conditions are mutually exclusive, so that at most one adjustment condition is explicitly satisfied in all cases.

[0028] If no adjustment conditions are met, it is considered that autonomous driving functionality is not currently available, and the process returns to step S1 in the next time step.

[0029] However, if one of the adjustment conditions is met, the autonomous driving function is adjusted in step S3. Specifically, the guidance range is adjusted, particularly by limiting the guidance range compared to the basic guidance range specified at the system boundary. This limitation is achieved by redefining the guidance boundary parameters used for vehicle guidance measures. The guidance boundary parameters of the reduced guidance range may be assigned at least in part to the adjustment conditions met, but it is also conceivable that the guidance boundary parameters of the reduced guidance range may be determined at least in part using current environmental parameters.

[0030] Here, the limitation of the guidance range is achieved, in particular, by eliminating specific driving maneuvers or restricting their use to a limited range, which is achieved, in particular, by reducing the maximum permissible dynamic parameters. Thus, for example, overtaking and / or lane-changing maneuvers can be eliminated, and / or the maximum speed, lateral acceleration, etc., in general or specific to the driving maneuver can be reduced. Thus, for example, slower cornering can be achieved. The maximum value of relative dynamic parameters (e.g., time distance to the vehicle ahead) can also be more strictly limited than the basic guidance range.

[0031] In step S3, along with the adjustment of the autonomous driving function, a prompt message is also output acoustically and / or optically to indicate this adjustment to the driver of the motor vehicle. The prompt message may also include a specific description of how the guidance range has been narrowed, such as explaining the canceled driving maneuvers, lower maximum dynamic parameters, etc.

[0032] Then, the autonomous driving function is provided in such a modified way that if the autonomous driving function is already activated, it continues to operate within the new guidance range; otherwise, if the autonomous driving function is activatable for the driver, it can be output to the driver as a prompt, as is known in principle.

[0033] Of course, the system will then continue to monitor whether the current environmental parameters continue to change, or even whether the system boundaries of step S1 are met again so that autonomous driving functions can be provided again within the full range.

[0034] Figure 2 A schematic diagram of a motor vehicle 1 according to the present invention is shown. The motor vehicle includes a vehicle system 2, which provides autonomous driving functions for fully automatic guidance of the motor vehicle 1. The vehicle system 2 includes a control device 3, which is a controller in this case. The control device 3 is designed to perform a combination Figure 1 The method described.

[0035] To determine current environmental parameters, but also for other purposes (such as the autonomous process itself), the vehicle may include sensors 4 (e.g., radar sensor 5), cameras 6, etc. Furthermore, communication data that also allows conclusions about current environmental parameters to be drawn can be received via communication device 7. Prompt information can be output via output device.

Claims

1. A method for operating a vehicle system (2) that provides an autonomous driving function for fully automated guidance of a motor vehicle (1), the autonomous driving function being usable within a system boundary described by at least one system boundary parameter to be obeyed for environmental parameters describing environmental conditions, such that autonomous vehicle guidance measures, particularly driving maneuvers, are determined and executed within a basic guidance range described by at least one basic guidance boundary parameter. Its features are, If at least one relevant current environmental parameter violates at least one system boundary parameter, at least one adjustment condition for evaluating the current environmental parameter is checked. If the adjustment condition is met, autonomous vehicle guidance is provided with a narrowed guidance range described by a guidance boundary parameter that depends on the satisfied adjustment condition and / or the current environmental parameter.

2. The method according to claim 1, characterized in that, The current environmental parameters refer to weather conditions and / or road conditions.

3. The method according to claim 1 or 2, characterized in that, At least one guidance boundary parameter, which is adjusted restrictively within a guidance range that is reduced compared to the basic guidance range, excludes at least one driving maneuver, especially overtaking and / or lane changing.

4. The method according to any one of the preceding claims, characterized in that, At least one guide boundary parameter is restrictedly adjusted within a guide range that is reduced compared to the basic guide range, particularly describing the reduced, maximum permissible dynamic parameters, especially the maximum speed and / or maximum angular velocity and / or maximum longitudinal acceleration and / or maximum lateral acceleration and / or time distance to the vehicle ahead, depending on the driving maneuver.

5. The method according to any one of the preceding claims, characterized in that, With autonomous driving capabilities provided within a narrower guidance range, prompts are sent to at least one occupant of the vehicle, particularly the driver.

6. The method according to claim 5, characterized in that, The prompt message describes the method of limiting the scope of guidance.

7. The method according to any one of the preceding claims, characterized in that, Multiple adjustment conditions are used, which are tailored to different environmental parameters and / or have different assigned narrowed guide ranges.

8. The method according to claim 7, characterized in that, At least one set of adjustment conditions is used for different sub-intervals of the current environmental parameter values ​​that violate system boundary parameters, wherein each of these adjustment conditions is assigned a narrowing guide range describing progressive restrictions.

9. The method according to any one of the preceding claims, characterized in that, The current environmental parameters are determined by sensor data from at least one sensor (4) of the motor vehicle (1) and / or by operating data from the motor vehicle (1) and / or by communication data from the communication device (7) of the motor vehicle (1).

10. A motor vehicle (1) having a vehicle system (2) having a control device (3) the vehicle system providing autonomous driving functions for fully automatically guiding the motor vehicle (1), wherein, The control device (3) is designed to perform the method according to any one of the preceding claims.

11. A computer program, when running on a control device (3) of a vehicle system (2) providing autonomous driving functions for fully automated guidance of a motor vehicle (1), causes the control device (3) to perform the steps of the method according to any one of claims 1 to 9.

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