Method for operating an autonomous vehicle

Abstract

The invention relates to a method for operating an autonomous vehicle (1). According to the invention, the vehicle (1) is automatically changed to the adjacent free lane (F2) on the outside of the curve when it is identified that: - the vehicle (1) approaches a curve (K); - there is an adjacent free lane (F2) on the outside of the curve for the vehicle (1); - there is a field of view limitation of at least one acquisition unit (2) of the environmental sensor system in the direction of travel of the vehicle (1) due to the curve (K) ahead; and - there is an extended braking distance of the vehicle (1) and / or other vehicles and / or a reduced ground adhesion in the curve due to road conditions relative to a predetermined target value. The invention also relates to a device for carrying out such a method and a vehicle (1) comprising such a device.

Description

Technical Field

[0001] This invention relates to a method for operating an autonomous vehicle.

[0002] The present invention also relates to an apparatus for performing this method and a vehicle including such an apparatus. Background Technology

[0003] DE 10 2011 100 907 A1 discloses a method for determining the road condition of a road located in front of a vehicle, wherein the road surface is measured using an imaging sensor and the image data acquired using the imaging sensor is evaluated using an evaluation unit to determine the road condition from the image data. Terahertz electromagnetic radiation is emitted toward the road surface using a transmitting unit of the imaging sensor and the terahertz electromagnetic radiation reflected at the road surface is detected using a receiving unit of the imaging sensor. Using the evaluation unit, in order to determine the road condition from the acquired image data within an image area exhibiting higher reflection of terahertz electromagnetic radiation, water cover, snow cover, and / or ice cover on the road surface are identified. The road analysis results are used by various vehicle driver assistance systems in their operation. Summary of the Invention

[0004] The objective of this invention is to provide a novel method for operating an autonomous vehicle, an apparatus for performing this method, and a vehicle including such an apparatus.

[0005] According to the present invention, the task is accomplished by a method having the features of claim 1, an apparatus having the features of claim 9, and a vehicle having the features of claim 10.

[0006] Advantageous designs of the present invention are the subject of the dependent claims.

[0007] In a method for operating an autonomous vehicle, according to the present invention, when a...

[0008] - The vehicle approaches the curve.

[0009] - There is an adjacent empty lane on the outside side of the curve for vehicles.

[0010] -Due to the curve ahead, there is a field of view limitation for at least one acquisition unit of the environmental sensor system facing the direction of vehicle travel.

[0011] - When, due to road conditions, the braking distance of a vehicle and / or other vehicles is increased relative to a predetermined target value in a curve, and / or the ground adhesion is reduced,

[0012] Automatically change the vehicle to an adjacent empty lane on the outside of the curve and / or automatically reduce the vehicle's current speed.

[0013] In the operation of autonomous vehicles such as trucks, it is particularly important to always travel at the maximum permissible speed to minimize the time the vehicle and its cargo spend on the road from an economic perspective. When entering a curve, visibility into one's own lane can sometimes be limited within its effective range due to obstructions such as guardrails, construction zones, or vegetation at the edge of the road. This is especially true for the innermost lane of the curve. Furthermore, road conditions significantly affect the stability of vehicles and other vehicles in curves. For example, road conditions affecting tire-to-road grip can make motorcycles more prone to slipping in curves.

[0014] By using this method and by consequently changing lanes to the outer lane and / or automatically reducing the current speed, the field of vision of at least one acquisition unit in the curve area can be preventively increased, and the vehicle can preventively navigate the curve at an optimized speed. Therefore, the vehicle can promptly initiate emergency braking and / or evasive maneuvers when there is a non-run-over object on its road, significantly reducing the risk of collision. In particular, by determining the driving conditions early, the danger to a fallen motorcyclist can be identified, and the vehicle's automated control related to road and speed selection can be adjusted accordingly. Therefore, the risk of collision, especially with objects obstructed by curve visibility and potentially people on the road due to accidents caused by driving conditions, such as motorcycle accidents, is significantly reduced.

[0015] In one possible design of this method, the increased braking distance and / or reduced ground adhesion of the vehicle and / or other vehicles relative to a predetermined target value due to road conditions are identified by detecting gravel and / or precipitation such as rain, snow, or ice on the road surface. Preferably, the target value is variably set based on the vehicle's current speed. Especially when the road surface is affected by gravel and / or precipitation, the adhesion between the vehicle tires and the road surface is very low. This results in a long braking distance and a significantly increased risk of skidding for motorcyclists in corners. By taking this performance into account when determining road conditions, vehicle cornering can be stabilized, and the risk of colliding with other vehicles cornering, especially motorcyclists who have already fallen or are in the process of falling, can be significantly reduced by adjusting the vehicle's driving style. That is, based on the risk of motorcycle skidding in corners, the vehicle's driving parameters can be adjusted in advance before cornering to avoid colliding with motorcycles and / or people involved in or after motorcycle accidents.

[0016] In another possible design of the method, a field-of-view limitation is identified when the field of view of at least one acquisition unit falls below a predetermined threshold, wherein this threshold is variably set based on the vehicle's current speed. Specifically, the higher the current speed, the lower the threshold. Lane changes are triggered, for example, when the field of view of at least one acquisition unit falls below the threshold. The field of view is enhanced by changing lanes to the outside of curves, thereby improving the reliability of autonomous driving and enabling the vehicle to at least substantially avoid collisions with non-runaway objects through braking and / or evasive maneuvers, where traffic participants in the vehicle's surrounding environment are taken into account.

[0017] In another possible design of this method, the presence of an outer lane on a curve is determined based on map data from a digital map and / or at least on signals collected by vehicle cameras. This allows lane changing to be initiated only when reliable information about the presence of an outer lane on a curve exists, thereby improving road traffic safety.

[0018] In another possible design of this method, lane changing is performed based on the traffic density measured ahead of the vehicle. Here, lane changing is particularly performed when the vehicle is traveling essentially alone over a distance or when the distance behind the vehicle is sufficient to allow the vehicle to return to its initial path after passing the curve.

[0019] In another possible design of the method, the vehicle's current speed is adapted to the visibility limitations of the at least one acquisition unit caused by curves and / or mountains. When the visibility of the at least one acquisition unit is relatively small, the vehicle's current speed is reduced to improve, for example, safety while driving, wherein another threshold related to visibility can be set for this purpose.

[0020] In another possible design of the method, the required field of view of the at least one acquisition unit is determined based on the predicted current vehicle braking distance, which is related to the vehicle's maximum natural deceleration and natural speed, i.e., the current travel speed. In particular, the higher the current travel speed, the larger the required field of view of the at least one acquisition unit, because the braking distance increases with increasing travel speed. Therefore, it is possible for the vehicle to initiate braking when it detects a non-runaway object on its road, thereby at least substantially preventing a collision with the object.

[0021] According to the present invention, the apparatus for performing the aforementioned method is characterized by having a data processing unit connected to at least one acquisition unit of the environmental sensor system. This data processing unit is designed to identify, as a prerequisite, whether:

[0022] - The vehicle approaches the curve.

[0023] - There is an adjacent empty lane on the outside side of the curve for vehicles.

[0024] -Due to the curve ahead, the field of view of at least one acquisition unit of the environmental sensor system oriented towards the vehicle's direction of travel is limited.

[0025] - In curves, due to road conditions, there is an increased braking distance and / or reduced ground adhesion for vehicles and / or other vehicles relative to a predetermined target value.

[0026] The data processing unit is also designed to transmit the corresponding information to the motion trajectory generator when the aforementioned preconditions exist. The motion trajectory generator is designed to generate at least one motion trajectory for changing lanes to an empty lane on the outside of a curve and to transmit the generated motion trajectory to the vehicle's actuators and / or automatically reduce the vehicle's current speed.

[0027] With this device, the vehicle can change lanes to the outer edge of a curve and adjust its speed accordingly, thereby preventively increasing the field of vision of at least one acquisition unit within the curve area and preventing the vehicle from navigating the curve at an optimized speed. Therefore, the vehicle can initiate emergency braking and / or swerve maneuvers when there is a non-run-over object on its road, significantly reducing the risk of a collision. In particular, by determining the driving conditions early, the danger to a fallen motorcyclist can be identified, and the vehicle's automated control related to road and speed selection can be adjusted based on this danger. Thus, the risk of colliding with objects, especially people on the road whose vision is obstructed by curves and who may be involved in accidents caused by driving conditions, such as motorcycle accidents, is significantly reduced.

[0028] Furthermore, the device can be an integral part of a vehicle designed as an autonomous truck or autonomous car, where traffic safety can be optimized, in particular, by means of the device and method described above. Attached Figure Description

[0029] The embodiments of the present invention will be explained in detail below with reference to the figures, wherein:

[0030] Figure 1 The illustration shows a vehicle with a data acquisition unit along with objects within the data acquisition range that cannot be run over by the vehicle.

[0031] Figure 2 The illustration shows a road segment with multiple roads and vehicles traveling on the outer edge of curves;

[0032] Figure 3 The illustration shows the road segment including vehicles traveling on the inside of the curve. Detailed Implementation

[0033] Corresponding components are labeled with the same reference numerals in all drawings.

[0034] Figure 1 The image shows a side view of vehicle 1 along with an object 3 that cannot be rolled over on the road FB of vehicle 1 within the detection / acquisition range E of the detection / acquisition unit 2 of the environmental sensor system. Figure 2 and 3 The driving road segment F is shown, which has roads F1, F2 and F3, F4 for each driving direction, wherein the driving road segment F is winding, that is, it has curves K.

[0035] For example, a vehicle 1 designed as a truck, and especially one operating in an autonomous driving mode when there is no vehicle user in vehicle 1, Figure 2 On the F2 road, which is on the outer side of the curve, and in Figure 3 Driving on the inner side of the curve in F1.

[0036] Vehicle 1 includes a data processing unit 4 connected to multiple acquisition units 2 of the vehicle 1's environmental sensor system, wherein the acquisition units 2 are designed to be radar-based, lidar-based, and / or camera-based. Additionally, vehicle 1 has a satellite-assisted positioning unit (not shown in detail) that continuously receives position signals to determine the vehicle 1's current position.

[0037] This autonomous vehicle 1 is located within existing infrastructure based on signals collected by an environmental sensor system, location signals, and map data based on digital maps stored on the vehicle side, and the driving behavior of the vehicle 1 is coordinated with traffic participants determined based on signals collected by the environmental sensor system.

[0038] Onboard environmental sensor systems possess measurement characteristics determined by sensor type, configuration, and physical boundary conditions. Generally, environmental sensor systems represent the coordination of multiple functional tasks. For example, a LiDAR-based acquisition unit 2 can be used to perform three-dimensional measurements of the traffic-related area in front of vehicle 1, where the semantics of the scene measured in front of vehicle 1 are determined based on signals acquired by the camera-based acquisition unit 2, including the identification of traffic signs and traffic lights.

[0039] The resulting requirements determine the parameters of each acquisition unit 2, such as baseline width, focal length, viewing angle, pixel density, and sensor type, especially whether the signal from the acquisition unit 2 based on the camera is acquired in color or monochrome.

[0040] The following describes a method for automated driving operation of vehicle 1, wherein the method focuses on a lidar-based or camera-based acquisition unit 2, also known as a field of view or cone of vision, with an acquisition range E facing forward of vehicle 1 and the acquisition unit 2 being, for example, a so-called long-range sensor.

[0041] There are no pedestrians in front of vehicle 1, and there is a high requirement for the field of vision of the acquisition unit 2, as well as the requirement to detect object 3 in order to react appropriately to it. In order to avoid vehicle 1 colliding with the detected object 3, it can initiate, for example, emergency braking and / or automatically drive onto an avoidance trajectory if the object is detected in time.

[0042] The detection range of the non-rollable object 3 is relatively far. The acquisition unit 2, as described above, is based on a lidar sensor or a camera sensor, which has a certain field of view. The acquisition unit 2 can also be composed of multiple individual sensors.

[0043] The purpose of the automatic driving operation of vehicle 1, especially freight trucks, is to travel at the maximum possible speed so as to minimize the time that vehicle 1 and its cargo spend en route for economic reasons.

[0044] When driving through curve K, the field of vision of the acquisition unit 2 facing ahead of vehicle 1 may be limited by guardrails, structural / building areas and / or vegetation. This is especially true for roads F1 on the inside of curves.

[0045] In order to react appropriately to potential non-runaway objects 3 on their respective roads F1 and F2 by braking and / or avoidance, vehicle 1 needs to reduce its current speed, thereby extending the time vehicle 1 is in driving operation.

[0046] If vehicle 1 is like Figure 3 As shown, when driving on road F1, which is on the inner side of the curve, the field of view and consequently the acquisition range E of acquisition unit 2 are limited. However, if vehicle 1 is driving on road F2, which is on the outer side of the curve, the field of view is increased, such as... Figure 1 As shown.

[0047] Object 3 is, for example, a motorcycle. Especially in the case of motorcycles, there is a danger on curves where, due to reduced traction between the motorcycle tires and the road surface, the motorcyclist loses control and skids. In this situation, they may drift onto oncoming traffic lanes F1 and F2.

[0048] This is Figure 2 and Figure 3The example is illustrated below. In this case, the object 3, designed as a motorcycle, slips and enters the oncoming road and stops there. When there is such a road surface affected by gravel and / or precipitation, the adhesion of the tires of vehicle 1 to the road FB is also reduced, resulting in an extended braking distance. Therefore, in order to increase the field of view and the acquisition range E of the acquisition unit 2 and avoid collisions with the object 3, such as a motorcycle, it is stipulated that when it is detected that vehicle 1 is approaching a curve K, there is an adjacent empty road F2 on the outside of the curve of vehicle 1, the field of view of the acquisition unit 2 in the direction of travel of vehicle 1 is limited due to the curve K ahead, and there is an extended braking distance relative to a predetermined target value due to road conditions in the curve and / or reduced ground adhesion of vehicle 1 and / or other vehicles, such as the object 3 designed as a motorcycle, vehicle 1 is automatically changed to the adjacent empty road F2 on the outside of the curve, and the current speed of vehicle 1 is automatically reduced if necessary.

[0049] Therefore, it is possible to reduce the probability of injury in curved situations where visibility is obstructed, by using a data acquisition unit to identify hazards before or during curve travel, such as gravel and / or precipitation such as rain, snow, or ice in the area before curve K or in the curve itself. The focus is particularly on the inner lanes F1 and F2, as in the case of a (motorcycle) accident, the force generated could cause people or parts of the vehicle to move into the lane, thus increasing the risk of injury.

[0050] This allows for a preventative reduction in driving speed when obstructed by a curve and / or a move to the outer edge of the curve (FS2) to improve visibility toward curve K, thereby reducing braking distance in emergency braking situations and allowing for earlier assessment of the feasibility of possible evasive maneuvers.

Claims

1. A method for operating an autonomous vehicle (1), characterized in that, When identified - The vehicle (1) is approaching the curve (K), - There is an adjacent empty lane (F2) on the outer side of the curve of the vehicle (1). - Due to the aforementioned curve (K) ahead, the field of view of at least one acquisition unit (2) of the environmental sensor system facing the direction of travel of the vehicle (1) is limited, and - When, due to road conditions, the braking distance of the vehicle (1) and / or other vehicles is extended relative to a predetermined target value in the curve, and / or the ground adhesion is reduced, Automatically change the vehicle (1) to the adjacent empty lane (F2) outside the curve and / or automatically reduce the current speed of the vehicle (1). When the field of view of the at least one acquisition unit (2) is lower than a predetermined threshold, a field of view limitation is identified, wherein the threshold is variably set according to the current driving speed of the vehicle (1).

2. The method according to claim 1, characterized in that, By detecting gravel and / or precipitation on the road surface, the system identifies the increased braking distance and / or reduced ground adhesion of the vehicle (1) and / or other vehicles relative to a predetermined target value due to road conditions.

3. The method according to claim 1 or 2, characterized in that, The predetermined target value is variably set based on the current driving speed of the vehicle (1).

4. The method according to claim 1 or 2, characterized in that, The existence of the outer lane of the curve (F2) is determined based on map data from the digital map and / or at least based on signals collected by the vehicle's (1) camera.

5. The method according to claim 1 or 2, characterized in that, The lane change is performed based on the traffic density measured in front of the vehicle (1).

6. The method according to claim 1 or 2, characterized in that, The current speed of the vehicle (1) is adapted to the visibility limitations of the at least one acquisition unit (2) caused by curves and / or mountains.

7. The method according to claim 1 or 2, characterized in that, The required field of view of the at least one acquisition unit (2) is determined based on the predicted current braking distance of the vehicle (1).

8. An apparatus for performing the method according to any one of claims 1-7, characterized in that, A data processing unit (4) is provided, which is connected to at least one acquisition unit (2) of the environmental sensor system of the vehicle (1) and is designed to identify, as a prerequisite, whether: - The vehicle (1) is approaching the curve (K), - There is an adjacent empty lane (F2) on the outer side of the curve of the vehicle (1). - Due to the aforementioned curve (K) ahead, the field of view of at least one acquisition unit (2) of the environmental sensor system facing the direction of travel of the vehicle (1) is limited, and - In this curve (K), due to road conditions, there is an increased braking distance and / or reduced ground adhesion for the vehicle (1) and / or other vehicles relative to a predetermined target value. And when the aforementioned preconditions exist, the corresponding information is transmitted to the motion trajectory generator, which is designed to generate at least one motion trajectory for changing lanes to the empty lane (F2) outside the curve and transmit the generated motion trajectory to the actuation device of the vehicle (1) and / or automatically reduce the current driving speed of the vehicle (1).

9. A vehicle (1) comprising the device according to claim 8.

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